Boy I really stepped in it now...  Microraptor. For a long time I avoided paraves, Microraptor, the whole dino-bird subject because; there is a lot of talk about maniraptorans on the web already; I enjoy focusing on "meatosaurs" (and still do); and, well, quite literally this whole backwater of quasi dinosaur, quasi bird conundrums literally ruins people. I mean it is a war zone out there folks. Seriously now, academic career types - not just free spirited blogger/idea spinners like yours truly - have gotten their heels so dug in on various sides of the debate it is quite astonishing. The stakes are high in this subject of birdy origins and history will see winners and losers... So why not dive in with Microraptor probably one of the most celebrated, controversial, and perplexing dinosaurs and certainly maniraptorans of the last 25 years? I would definitely put this animal in an unholy triumvirate with Deinonychus and Archaeopteryx in terms of paradigm shifting, scratching your head, game changing iconoclastic status. It really is an odd bird and one we still have loads of unanswered questions about.

closeup cast credit Hiroshi Nishimoto CC 2.0

So for this piece I am mainly going to side step questions about the aerodynamic efficiency of Microraptor. I don't have a wind tunnel, nor a model to test it in, nor an advanced understanding of aerodynamics. To summarize my current opinion on Microraptor's flight capability I am hedging towards rather limited flight capability - possibly more of a burst flyer of short distances, great maneuverability, with some gliding ability though far from ideal due to all that drag it incurs. I think that the biplane model with the legs spread wide is far from established as I still have questions about ,well, could it anatomically splay its legs? So for now I am going to go with a base line of fairly limited flight capability with pretty good maneuverability and pitch control via the tail and hind wings. I am not wedded to this interpretation and am open to new insight.

I will be working from this point in my attempt at a reasonable lifestyle analysis of this critter. I think it fairly conservative and in line with much of the research into this animal.

William Beebes' prescient 1915 "Tetrapteryx" 1915 public domain

Now onto another very contentious issue: terrestrial or arboreal? In order to untangle why this issue is so contentious - I don't think it need be actually - it is worth looking at this question through another lens. The issue of terrestrial versus arboreal in Microraptor has double implications because whether or not this animal was terrestrial or arboreal provides a robust layer of argument to the issue of the competing ground up or trees down hypotheses in the origin of flight in aves proper. And we all know how contentious that issue is and how various factions have their heels dug in on either side of the debate.

The answer to the question of arboreal versus terrestrial habits in Microraptor is quite literally that there is no question of arboreal versus terrestrial in Microraptor's head. And it is in the headspace of Microraptor that we need to get into here - not the head of a tenured professor with a life times' academic stake in the question of ground up or trees down origin of flight. That is quite literally the last head we need to get into in this question. We need to get into the head of a 1 to 2 kilogram predator of small things. An animal that goes recklessly and relentlessly where its prey is. If that prey is roosting 20 meters up a giant old growth ginkgo tree by golly that is where Microraptor is going. If prey is swimming and swarming in the shallows of a lake Microraptor is having a go at that prey. If prey is scurrying from the safety of a burrow in the still of the night Microraptor is right there to greet them. If prey is secreted away deep inside the hollow of fallen tree trunk, Microraptor is sniffing out that quarry and going in that rotten log and making their life hell. Microraptor is kicking ass and taking names and if you are a small swarming, swimming, flying, or scurrying thing and living in the same neighborhood as Microraptor you better watch your back because Microraptoris coming.



"Lock up your children the axeman is coming"

Yes in the trees, in the shallows, in the little cracks and crevices of the environment where the small things hide out Microraptor is going there. If Microraptor could evolve a human intelligence and humour and knew of our debates concerning it Microraptor would be laughing at the pedantic back & forth of terrestrial versus arboreal because Microraptor goes where Microraptor wants to go. Microraptor does not see a sharp division of terrestrial versus arboreal realms. Microraptor sees a 3 dimensional world where the subterranean, aquatic, terrestrial, arboreal, and aerial bleed into one another and Microraptor bleeds into them and exploits them all as it sees fit.

Seeing the world in such a 3 dimensional matrix of positional vortexes is not at all dissonant with how modern supple fingered, clawed, predatory, and small bodied tetrapods exploit and utilize their environment. We see echoes of this multi-functionality in mustelids, varanids, viverids, and probably most intuitively felids, especially our own house cats. I think it was Thomas Holtz who compared microraptors to small felids and I think the comparison is very apt. If you have ever wondered why your house cat has a penchant for seeking high ground - both to hide from threats and survey potential prey - you are seeing echoes of Microraptor in fluffy. I can also recall Darren Naish mentioning in several blog posts that although microraptorines (and other dromies) did not have highly specialized arboreal capabilities that does not mean we should exclude them from scrambling around in the trees, bushes, i.e. exploiting the >shrubbery<.

Of course the bauplan Microraptor started with is different from mammals and lizards. Lacking the low body plan as well as the supple and flexible limbs and torso that allow other tetrapod predators such as lizards and mammals to excel at this particular eco-niche microraptorines evolved alternative solutions to the problems of navigating a cluttered, three dimensional eco-space. The wings on the forearms served to break falls that occurred at elevation, aide in terrestrial balance and pursuit, and provide gliding and flight. Note that I am not concerned with the question of >what< stimulated the evolution of the wings in microraptorines merely how such wings would be useful for a theropod navigating three dimensional space in the pursuit of small game. The >what< of this question (i.e. what caused evolution of wings on the forelimbs) may never be boiled down into a single causal factor but a multiplicity.

Getting back down to earth, literally, I want to address a bit of non-truth that has consistently swirled around microraptorines for a while now. That piece of misinformation - a truism that has always been asserted but never actually demonstrated - is that their "hind-wings" severely hampered terrestrial movement. I see this assertion upheld again and again in both scientific and popular discussions. The idea being presumably that such flight feathers would be a hindrance in locomotion, get caught up in vegetation , and generally cause a kerflunkle for any microraptor trying to just... walk around.  That animals with relatively long cursorial looking rear legs; that plot out very much like ground birds morpho-metrically; that this animal could not run or even walk well points to a very mal-adapted and cumbersome beast. Caught in sort of an evolutionary purgatory - not yet an accomplished flyer, glider or climber as well as a cumbersome terrestrial mover - such an animal begs for a quick extinction. Seriously this notion of a terrestrial limited Microraptor should have always have been a non-starter. Kind of like sauropods that could not walk on land. Or giant pterosaurs that could not fly.  The kind of "evolutionary experiment" that paleontologists like to posit but can't find any examples of in the real world. Because in the real world their overly cumbersome traits would select them for Darwinian elimination before they even had a statistical chance of entering the fossil record.

Again, we need to get back to what it means to be a predatory small bodied, hot blooded terrestrial tetrapod. You are not just an OKish hunter that sort of blunders through the environment hoping to get lucky enough to snag a meal or two. Such an animal would be selected for extinction quite readily. Nope you are an efficient, ruthless, and relentless hunter. Just look at the pedigree of hunting prowess in small felids and especially small mustelids (i.e. "weasel" types). The true acme of hunting prowess in mammals is not to be found in large canids or felids - they fail all the time. Small bodied predators have to catch a lot more due to their relatively higher metabolism and the relatively small size of their prey. They can't afford to only have a 5% success rate. They are hungry and they are coming. No reason to assume among predatory theropods microraptorines were not the acme of theropod hunting prowess. In fact evolutionary pressure and comparison to modern small bodied tetrapod hunters would dictate that they are.

I mean, come on now, just look at those legs.

Specimens by Jaime Headden CC3.0  (User:Qilong) - http://qilong.deviantart.com/art/Microraptor-Skeletons-27326378

Microraptorines could move and move around well on the ground. Assertions that the feathers on the legs would cause undue hardship and toil are simply not meted out when viewed against the panoply of abuse modern birds put their flight feathers through. I was recently watching the flock of California condors that are maintained at the Santa Barbara Zoological Gardens. Splendid birds and you really get a sense for the nuanced social dynamics at play when you watch them for some amount of time. One of the birds sort of crash landed into the branches of a large oak tree in the enclosure after a small skirmish. Mind you this was a California oak (not sure the species) and it had the harsh, spiky leaves of a oak adapted to the drought prone, semi-arid climate of California quite unlike the soft rounded leaves you might encounter on oak leaves in more verdant climes. Anyways, this was no soft landing that the condor made into the tree and it was totally caught up in the brittle, spiky canopy. The bird (second heaviest flying bird in North America) then proceeded to use its wings (e.g. its flight feathers) to literally "swim fly" through the brambly and spiky oak foliage until it could get up to a solid enough limb to perch upon. I got the feeling this was no extraordinary ordeal for the bird and had probably done it a number of times. Not a flight feather lost or even seemingly damaged. Long story short flight feathers - whether on the arm or leg - are not the wimpy structures sometimes assumed to be and are  deeply anchored within the dermis or even into the bone and can both receive and deliver substantial abuse and punishment. Microraptorine leg feathers were doubtless anchored well into the leg . Furthermore there is no reason that the feathers on the leg would not have been able to fold up against one another as the leg moved or crouched. It is also entirely possible that such feathers could be moved so as not to scrape against the ground. This is no different than what the flight feathers on the arms of birds and maniraptorans presumably are able to do.

Anyone who argues that bird feathers - especially the pennaceous "flight" feathers whether on the legs or arms - are prone to falling off, getting damaged, or just inhibiting to violent, physical interactions just has not been paying attention to what birds actually do.



Now that we put that whole notion of "could not walk well" to bed for maniraptorines I want to dive a bit deeper into potential uses for the leg feathers. I want to stipulate that these ideas are not mutually exclusive from any of the flight scenarios that people have posited for these animals. Remember that I am not concerned with could or how well Microraptor flew but creating a lifestyle portrait of a small animal killer. Being a specialized small animal killer is an easy inference given the diversity of, well, small animals found in the guts of Microraptor.

To make my case I first want to bracket Microraptor between several other theropods that sported leg feathers. Yes leg feathers were quite en vogue look for several theropods back in the day and not all of them were microraptorines.

Pedopenna daohugouensis. Remember this guy? Yeah I don't either. Just another in the long and confusing line of maniraptorines getting pulled out of the ground in China, I would be lying to you if I don't constantly have to 2x check the names of these guys. Except this species is one that you should take note of. First of all it predates Microraptor and the other Liaoning/Jehol fauna as it dates to somewhere in the mid-late Jurassic (age of the Daohugou beds are debated) but more importantly for our purposes here the legs are feathered - they had hind wings!! The legs are all we really know of this animal and according to wiki: "the long pennaceous feathers of the foot... differ from those of animals like Microraptor. Pedopenna hind wings were smaller and more rounded in shape. The longest feathers were slightly shorter than the metatarsus at about 55 mm (2 in.) long. Additionally, the feathers of Pedopenna were symmetrical, unlike the asymmetrical feathers of some deinonychosaurs (including Microraptor) and modern birds."

The symmetrical feathers of the hind wings in Pedopenna (and Anchiornis btw) are interesting as this suggests that they did not have a use aerodynamically. The hind wings are potentially vestigial and point to a flighted or at least gliding ancestor for Pedopenna (Xu & Zhang, 2005). This invokes the strong potential for "microraptorine" style flyer/gliders going back into the mid-Jurassic - very cool. This also suggests that flight could have evolved, got lost, got regained, and evolved in multiple parallel branches over a fairly long span of time. However I am not quite so sold on Pedopenna and Anchiornis being secondarily flightless. If this was true why would they so quickly lose  asymmetrical feathers? Would not asymmetrical feathers still be of use in short glides and other such aerial ventures? I mean, these were not large animals so retention of some aerial ability would still be of use in gliding one would presume?

Time to highlight the seldom mentioned fact that the giant compsognathid Sinocalliopteryx also is noted for non-pennaceous feathers along the back of the metarsus and longer ones on the back of the thigh. These feathers did not form a hind wing nor are compsognathids considered to be on their way to flightedness or secondarily flightless. Yet there was some congruence in evolving feathers along the trailing edge of the lower legs in these disparate animals.

To add a further layer to the enigma of hind wings and lower leg feathers is the amazing microraptor on steroids, Changyuraptor a turkey sized double winged and exceptionally long tailed microraptorine that, despite its size, still points towards being somewhat flight capable or at least gliding.

turkey sized microraptor Changyuraraptor credit Emily Willoughby CC4.0

Although I have my doubts about how long this animal could sustain powered flight, it is always good to remember that wild turkeys and peacocks do fly and they also go into trees as well.



I do think it pays to take a look at these flying large galliforme videos. Notice the seemless transition from an arboreal start in the trees to a short distance flighted phase effortlessly transitioning to an efficient terrestrial phase. Even at this size a turkey sees, interprets, and inhabits its world in a 3-dimensional matrix. I guess this "ground bird" with no obvious arboreal adaptations never got the message that it could not use the trees as it sees fit. Not impressed with flying turkey how about flying peacocks - another "ground bird" that goes where it wants to.


And watch these peacocks in China seemingly sail down en mass from elevation. Reminds me a lot of those turkeys sailing in from the tree tops in the earlier video. Very cool.


We can look at Microraptor not as an isolated hind wing animal but one that slots, or is bracketed in a sense not just phylogenetically but behaviorally,  between a number of hind wing or at least feathered leg/metatarsal having theropods. And I think it important to speak towards ecological and behavioral congruity in these theropods because, irrespective of phylogeny, similar lifestyles often confer similar adaptations by convergence.

And the unifying behavioral characteristic that unified microraptorines, Anchiornis, Pedopenna, and Sinocalliopteryx is that they were all terrorists of small game. I have actually discussed Sinocalliopteryx gigas before here. Sinocalliopteryx was obviously not arboreal and it was not flighted, near flighted, or secondarily flightless. But it was really good at snacking on animals that were flighted and/or more inclined towards aerial/arboreal capabilities than it was hence the belly full of dromie leg & enantiornithines. Because of this the authors suggest that it was a stealth hunter, a notion that is hard to dismiss.

Unpacking what it means to be a stealth hunter with a theropod bauplan I believe is key to illuminating what stimulated the evolution of hind wings.

When you are a hunter of small things that means that you have to go to where the small things are at. That implies negotiating tight spaces and deep, dense vegetation. If you are negotiating this eco-morphospace as a small mammal, lizard, or better yet snake - no problem you are already low to the ground with supple legs and torso. But if you have the stiff torso and the tall stiff action limbs of a theropod there is less of an exaptation for maneuvering in such tight places which means there is even more impetus on stealth. A theropod stealthy stalker of small game has to get as close as it can as quietly as it can because whatever you are stalking - chances are that once it detects you it has the better capabilities in navigating tight spaces (or just flying or swimming away). And so imagine the stealthy stalking ability of modern herons but imagine it occurring not while wading but while in deep vegetation. One of the problems such an animal would encounter is curtailing or muffling the disturbance and noise that would occur by walking on and brushing against vegetation/leaf litter/brush with those long, stiff action hind legs. A soft, padded foot would help with muffling footfalls. Likewise a trailing line of feathers along the back of the leg and going down the metatarsus to the foot would potentially muffle or curtail the audible "snapback" of brush that occurs when a leg moves through vegetation - especially dried and brittle twigs, stems etc. etc. Anyone who has done any significant off trail bushwhacking knows what I am talking about. As a tall biped we humans are especially noisy, cumbersome, and just maladapted for stealthy stalking through dense brush. In fact if you are going through dense brush in a group one will often find it necessary to grab a branch or stem that might in fact "snapback" and hit the person following you!! Theropods - which share with us a relatively tall, bipedal build - would face a similar dilemma of "noise pollution" as they moved through dense brush. Having a rearward guard of feathers along the back of the leg and foot would allow vegetation to be "caught" and eased back as the leg stealthily moved through it.

That modern ground birds lack such hind wings or even feathers on the back of their legs may in fact have more to do with a lack of birds engaging in cryptic, stealthy stalking of small game in dense brush. An eco-morph today dominated by mammals, snakes, and lizards.

So here we can draw a rough outline for the impetus and evolution of hind wings - appreciating their import in stealth - that is in fact congruent with what is seen in the fossil record.

A Rough Outline on the Evolution of Hind Wings

I Sinocalliopteryx gigas shows what a theropod with only the barest, incipient stages of this evolution would have. Just simple and small trailing lines of non-pennaceous feathers that assisted in stealthy movement through thick brush while stalking small and agile prey. Coelurosaurs had bigger and more audacious plans in their future so the hind-wing evolution and flight never became more realized in this group.

II Pedopenna, Xiaotingia & Anchiornis. From something similar to Sinocallipoteryx ecologically (albeit dromaeosaurine & smaller) animals like Pedopenna& Anchiornis would arise. The hind wing feathers are now pennaceous although they are not yet flight adapted as they are symmetrical (on both arm & leg wings). However these are true small game hunters of the underbrush as such they capably explored a more three dimensional realization of their environment, certainly more so than the relatively giant Sinocalliopteryx.  Although not exquisitely adapted for arboreal life they certainly found themselves up in the trees on occasion. The occasional fall was not an issue as both the arm wings and hind wings would serve as safety nets.

Credit Jaime Headden CC3.0 http://qilong.deviantart.com/art/The-Essence-of-Huxley-160904197

Despite consistent assertions to the contrary Anchironis and other hind-winged microraptorines were excellent terrestrial runners. Arguments against efficient terrestrial running have centered on the lack of leg feathers on modern ground birds. However these arguments have not accounted for a scientific control in terms of behavioral ecology. Big herbivorous ground birds are simply not ecologically comparable to stealthy, small game paravian hunters of dense vegetation. When stealthy hunting in deep vegetation is at a premium a trailing edge of feathers along the back of the leg will often develop in small theropods.




Is there a test for my argument that hind-wings & leg feathers are intimately associated with both stealth and a small game carnivorous lifestyle? Such a paravian would have to be showing a roughly comparable level of flight efficiency to microraptorines with one exception in that it was not a hunter of small game but an omnivore/insectivore/herbivore i.e. stealth was not a critical aspect of its lifestyle.

Turns out the fossil record does provide such a test and it's name Eosinopteryx brevipenna. Eosinopteryx  comes from the same time and place as Anchiornis and Brian Switek gave it an excellent summary article here. Personally I think Switek was very prescient in observing how the glut of feathered dino-bird things coming down the pike in last couple of decades has caused a bit of a "numbing" effect. We are not as excited about them as we once were. Switek maintains that specimens like Eosinopteryx might yet have special stories to tell. Eosinopteryx does indeed have a special story to tell I suggest. Eosinopteryx does not have hind wings and it shows a trend indicating decreasing predatory habits. Loss of predatory features includes the lack of a toe claw or even highly recurved foot  claws at all and very foreshortened snout with reduced dentition.


Now granted Eosinopteryx is not especially flighted, in fact the arms have been argued to be especially lacking in the mobility needed for flight. But that does not imply it could not have clambered into trees - as other contemporary paravians that did have hind wings likely did - and that it could not have used the arm-wings as a safety net for falls or gliding. Yet it lacked the hind wings of the contemporary but decidedly more predatory animals like Anchiornis. Anchiornis lacked asymmetrical flight feathers itself and, if flighted, was hardly a good pilot. The main deciding trait that separated Eosinopteryx from hind winged paravians I suggest is diminished predatory habits.

*Update 8/26 I had it pointed out to me via Matt Martyniuk that Sapeornis has some hind wing action going on as well as several other enantiornithines such as those from the new Crato formation: link
Although the hypothesis is not as robust as I constructed it do to these exceptions, it is still possible that a use in stealthy predation was still coopted into the ability to fly with better maneuverability with enhanced hind wings...

III Microraptor. From animals similar to Anchiornis Microraptor likely evolved. Microraptor kept the long hind legs and strong cursorial ability of these animals but improved upon their condition by improving utilization of 3-dimensional space. This revolution was chiefly executed via more efficient flighted ability and true asymmetrical flight feathers on the fore & hind wings. The hind wing feathers still allowed for stealth movement through thick vegetation but were now co opted for aerodynamic purposes.

Hind wings in Microraptor allowed two very important facets of predatory behavior. 1) They allowed for increased maneuverability in the air. 2) They allowed for a more stealth approach in the air.

Microraptor 4 winged flight credit David Krentz

Point 1 is strongly supported via the studies of Hall & Habib et al. (2012) A strong take home message of the work of Hall & Habib is the concept of a "drag tax" in Microraptor's flight. All of the surface areas that increased maneuverability in Microraptor incurred a consequence in terms of speed. As Microraptor negotiated a very cluttered and complex forest ecosystem such compromise was necessary.   And as I will argue further in a future post speed was not at the crux of Microraptor's predatory arsenal - maneuverability and stealth were its chief aims.

Point 2 is a new aspect I want to highlight that will be further embellished in my next post. The hind wing of  Microraptor - which I argue is an exaptation co opted by small dromaeosaurines (like Anchiornis) that enabled stealth stalking through thick vegetation - now in the flighted form allowed for an appreciable degree of sound muffling while the leg moved through air.

Swing any long cylindrical object through the air with speed - a bat, a twig, or a leg - and you will get an audible "whoosh" as the air rushes around the cylindrically shaped object and collides together on the rear side. But put a trailing edge of feathers on such an object you will appreciably diminish this said "whooshing" effect. Owls have taken this aspect of stealth approach to the extreme via the sound damping effects of their feathers. I am not suggesting that Microraptor had such capabilities as an owl but the concept remains true to point out. And any such advantage a predator can use, even it only incrementally increases its odds, is still a useful and tactical one.

To restate the angle I am taking - how to figure out how a small theropod bauplan most effiectively operated as a small game hunting animal - let me get back to brass tacks. Microraptor hunted small enantironithines - flighted "birds" that were well ahead of Micraptor in terms of flight adaptations. The superiority of enantiornithine flight speed was no hindrance to the success of Microraptor's predation on them. Because Microraptor was a predator and predators use every advantage that they can garner, Microraptor simply honored the time honored tradition of predators immemorial. It struck in the dark.

Why Microraptor was in fact a nocturnal stealth predator of the utmost capability will be addressed on my next post...

Night Hunting Microraptor credit Robin Liesens

papers

Godefroit, P., Demuynck, H., Dyke, G., Hu, D., Escuillie, F., Claeys, P. 2013.Reduced plumage and flight ability of a new Jurassic paravian theropod from China. Nature Communications. 4, 1394. doi: 10.1038/ncomms2389

Hall, JT, Habib, MB, Hone, DWE, Chiappe, LM. Hindwing function in four winged feathered dinosaurs. (2012) online

Ji, S., Ji, Q., Lu J., and Yuan, C. (2007). "A new giant compsognathid dinosaur with long filamentous integuments from Lower Cretaceous of Northeastern China." Acta Geologica Sinica, 81(1): 8-15




Xu, X. & Zhang, F. (2005). "A new maniraptoran dinosaur from China with long feathers on the metatarsus". Naturwissenschaften. 92 (4): 173–177. Bibcode:2005NW.....92..173X. doi:10.1007/s00114-004-0604-y. PMID 15685441.

Duane Nash

Pretty much ALL aspects of Microraptor have achieved special attention and thought. In this post/article - which is really a continuation of my take (and others too) on Microraptor as an especially diabolical and efficient predatory terrorist of all things small - I am going to highlight an aspect that has been startling, controversial, and plagued with misunderstanding, coloration. Ahem, not just coloration but structural coloration i.e. iridescence (Li, 2012).  More specifically that iridescence does not in fact preclude a nocturnal lifestyle.

Reader beware and tread carefully. Many of the arguments and thoughts I will bring forth stand on necessarily shaky ground. That is because issues of coloration, roosting behavior, iridescence, cryptic coloration, "cloaking" and other aspects of modern animals are woefully understudied and really on the cutting edge of modern animal research much less in long gone paravians. That does not mean I am not going to "go there" and in the end create a startling and believable lifestyle portrait of Microraptor gui.

For this piece I am going with the notion that the coloration of Microraptor is indeed black. Although arguments for degredation of color fibers etc etc. have been put forth I don't find them especially compelling. I might be wrong, but for this piece I am going with all black. Which really is a good policy for attire anyways, when in doubt go black. Or even better go with all black and iridescent if you really want to make a statement... For this piece I will address the two issues of black coloration and iridescence separately at first and then bring them together at the end.

credit George Hodan. public domain

Working from an all black plumage in Microraptor the mind necessarily thinks about modern day aves that don an all black attire. Various corvids come to mind - especially the common crow and raven - as well as grackles, and other various birds colloquially known as "blackbirds" in the passerine group. And this is where the confusion and typological thinking really mires us down in our interpretation of Microraptor.

For as much as we might be tempted to or find it "nice and tidy" to leverage arguments about what Microraptor did based on what modern birds do let us remind ourselves that Microraptor was not a bird nor was it ancestral to birds. It was its own thing. More so than that there is a tremendous gulf of time between Microraptor and modern birds - especially advanced "blackbird" type passerines. The environment is exceptionally different between what Microraptor inhabited and where modern "blackbird" gestalt birds generally thrive. Indeed a cool temperate rain forest dominated by giant old growth gymnosperm trees and lakes is about as far from the prairie like, open grassland type habitats that many "blackbird" type birds thrive in. Not to mention the differences in ecology between Microraptor - as yet only known to have eaten flesh - and the more granivorous or omnivorous tendencies of grackles, corvids and other passerine grassland thriving "blackbird" types.

I must ask some questions concerning the repeated occurrence of "blackbird" type birds in open grassland dominated habitats namely, "Why evolve a dark conspicuous coloration that highlights your presence to potentially other color vision attuned avian predators during the day?" You know it's true. Just look at a flock of crows foraging in a vacant lot or a flock of any of a number of blackbirds, whether the vegetation is flush with new growth and is bright green or it is brown and yellow after months of little rain these birds stick out like sore thumbs. Seems a little maladaptive does it not? Unless of course it is not actually maladaptive but exquisitely adaptive actually...

Blackbirds & Starlings in field credit USDA

And here I have to venture forth a hypothesis - a reasonable enough one I think - that the black or darkened coloration of many open habitat communal foraging birds is highly contrasting with the environment for a reason and that is in order to achieve group cohesion. I honestly don't know if this has been suggested before ;') . Birds can detect other foraging birds from distance and therefore keep social unity. More individuals in one place will actually lower the predator risk to any one individual at the same time allow more eyes for predatory vigilance. Having a dark black coloration would also be selected for as it allows birds to spot other birds foraging in food rich areas. That many of the birds engage in predatory mobbing type behavior plays into this.

There is another strategy that links group foraging "blackbird" type birds of open habitats and that is communal roosting in trees. Again here we see that the black or darkened coloration of these open habitat communal foraging birds plays a dual function at night. The dark coloration of these birds helps "cloak" them at night by, well, essentially mimicking the dark night sky. Even dark colored American coots may benefit from this as they also roost together at night next to bodies of water.

crows at roost credit (c) Daniel Hoherd

The defensive tactics of communal roosting birds is woefully understudied. Indeed what goes on at night in communal roosts is hardly looked at. I suspect there is a lot more going on than just sleep in some of the absolutely massive roosts that many birds engage in. The smell, noise, and general ruckus a large roost creates surely must act as a beacon to predators. Normally diurnal raptors might try to pick off roosting birds in early morning or late evening but black birds might just sort of disappear in darkness. Owls you would think could pick off roosting birds with ease but the predatory pressure that they put on roosting birds does not seem to be enough to dissuade the behavior. Likewise felids with their night vision would seem to be ideal candidates to depredate large roosts but cats are fairly near sighted and - when looking up at a dark colored roosting bird from the ground - the birds might just kind of disappear into the night sky. Check out this piece on what cats actually "see". I have done a little of my own field research into night roosting crows on Milpas street in Santa Barbara. A busy street during the day the crows gather in the large English laurels at night. When I checked out what was going on I could hear lots of activity actually. The crows engaged in subdued chatter, there was some movement and flight occasionally. But when my eyes tried to focus on any individual crow it was very difficult. I could kinda tell where they were at but they looked less like discernible objects and more like... negative space. Almost as if they were just black voids in the tree. They did not reflect the street lights - this roost is by a brightly lit gas station - but appeared to just suck up all the light that hit them.

credit Gustave Dore "Not the least obeisance made he" public domain

"And my soul from out that shadow that lies floating on the floor / Shall be lifted - nevermore!!"Edgar Allan Poe "The Raven"

But what works for communal nigh roosting blackbirds today in terms of cryptic coloration at night to avoid predators could work equally as well for a cryptic predator at night seeking to hide itself from prey... take home message: there is an argument to be made that black coloration in Microraptor is a useful element for a nocturnal stealth predator.

And now on to the iridescence.

"All modern iridescent birds are diurnal and therefore Microraptor was not nocturnal"

There it is, that stock line that in one fell swoop took the wind out of the sails in terms of nocturnal behavior (Schmitz, 2011) in Microraptor in many people's minds. Except such reasoning is not as ironclad as some might suggest.

And here is where I have to get all weird, paramilitary weapons technology on ya' all. Iridescence in many animals and plants might have a lot more to do with escaping - or possibly bewildering - detection rather than attracting it. So to prime you for it best check out a clip from one of the best sci-fi action films of all time and one of the best creature designs of all time: 1987's Predator:


The alien predator uses a technologically devised cloaking structural coloration to in fact mimic and blend into its surroundings. This ingenious camouflage was put to excellent use in the movie and the comparison to Microraptor in terms of an agile and multifaceted predator that takes advantage of 3-dimensional space - remember when Dutch (Arnold Schwarzenegger) realizes "It's using the trees."- and structural coloration should not go unnoticed. I realize some may have just checked out with that statement but yeah, I just kind of made the argument that a game hunting, cloaking alien from a Schwarzenegger movie is an analogy to take heed of when thinking about Microraptor.


Still with me? Ok time for a quick primer and some links to structural coloration of which iridescence is one of several types. Structural coloration is any microscopically structured surface fine enough to interfere with visible light. Visible light is not one color as we see it but contains all the colors we can and can not perceive. These "colors" have wavelengths and the microscopic structures in animals can alter these "colors" through wave interference. Based on the structures at hand wave construction can occur where colors are enhanced or wave destruction can occur where colors are diminished. The geometry of the material also plays a significant role as light both enters and refracts off of the structural material. This is why iridescent animals change colors depending on the angle you view them at as does soap bubbles... Still confused? Check out this primer on Iridescence "causes of color" and browse through the other sections.


Back to the question at hand which in this post is deconstructing the statement "Microraptor was not nocturnal because no modern day iridescent birds are nocturnal". My main lines of attack are two pronged and that there are two inherent assumptions implicit in the above statement 1) that iridescence is wholly and totally about "display" and therefore implies diurnal habits and 2) that Microraptor compares ecologically compatible with modern aves. Obviously I disagree with both assumptions and therefore strongly disagree with the logic of the argument itself.

I think one question that begs asking "Is iridescence totally or even mostly utilized in display in modern birds?" Of course in bird like a peacock the answer is an obvious YES!! But peacocks, like the various "blackbirds" I discussed earlier - at least the male - is a nocturnal tree rooster. Under the diminished light of the moon does the iridescence of the peacock perhaps play another subtle role in evading detection?


And what of the common occurrence of not only a dark or black coloration in many communal roosting birds combined with iridescence on one or both of the sexes to various degrees? One example that suggests more of a display trait in iridescence is grackles in which the male is the more iridescent example but starlings confuse the situation because both sexes are iridescent. This could be a case of mutual sexual selection but I suspect that nocturnal evasion aided by iridescent wave interference might be a hypothesis worth exploring. Is the iridescence of starlings totally about display? Or is there a dual functionality going on?

Sturnus vulgaris credit Tim Felke. CC2.0

Again, what goes on in nocturnal bird roosts? what tactics do they use to avoid predation? etc. etc., these are all areas of high speculation and little study. But the common occurrence of dark coloration, iridescence on one or both sexes, and nocturnal roosting is a topic just begging for more study. As I stipulated earlier there is much extrapolation and speculation inherent in this text and argument but I believe (pun intended) there is more than meets the eye with regards to iridescence.

Murmuration of Starlings preparing to roost. Scotland credit Walter Baxter CC2.0

Throwing another wrinkle in the equation what about the dark colored, iridescent cormorants? These are predators and like Microraptor inhabit and hunt in a dark, shadowy realm...

credit birds of the world

I am not completely sold on the notion that iridescence in modern birds is >completely< about display and I move to extend out arguments in terms of uses for iridescence outside of the rather arbitrary context of the restrictive phylogenetic bracket to include other organisms that utilize iridescence. Namely I want to focus on organisms that inhabit forested environments as deep forests serve as the most likely habitat of Microraptor. It is in the adaptational context - or adaptational bracket if you will - that we find not only the highest signal for iridescence in modern animals but also our most compelling arguments for iridescence as an aide in camouflage.

I start with the beetles. Shiny, iridescent, jewels of the animal kingdom. Yet their bright iridescent coloration shining and beckoning forth in the full light of day takes on a more muted, cryptic quality in the filtered light and shadow of deep forest canopy. Yet beetles do not use sexo-social display coloration as birds do but rely on chemical attractants. The high incidence of iridescence in beetles of the tropical forest just begs for an explanation in terms of camouflage and indeed this is the most compelling idea put forth.


Next I want to highlight animals closer both phylogenetically and ecologically to Microraptor which also sport iridescent coloration: snakes, but especially species that offers much utility in terms of understanding an iridescent forest hunting specialist of small things - the rainbow boa (Epicrates centria) of Central & South America and the Boelen python (Morelia boeleni) of Papua New Guinea.



What manner of beguiling tricks of light and shadow do these predators play on their prey in the dark cracks and crevices of their deep forested environment? It should not go unstated that both species are nocturnal...

Boelini Python credit Marc A. Spotoro

As is the case with iridescent beetles we can dismiss sexo-social display as an explanation for iridescence in these snakes as they don't actively display these structures and are more inclined towards scent and chemical cues rather than visual display. Microraptor, though displaced phylogenetically from these two boids, has much more in common with them ecologically and environmentally than the grackles and other grassland feeding birds often compared to it. I would offer that whatever benefits iridescence plays in the lifestyle of these two snakes Microraptor enjoyed as well.

credit Marc A. Spotoro

I would be remiss not to mention that there are several largely subterranean snakes that feature iridescence as well as the pertinent fact that the vast majority of cryptic, stealthy forest understory snakes don't feature iridescence. These observations create the argument that iridescence serves potentially no function at all. Perhaps some type of evolutionary byproduct of other happenings - one of Stephen Jay Gould's elusive "spandrels o fevolution".  Personally I don't think that is the case - the ubiquity of iridescence in numerous understory reptiles, birds, insects and plants points to some adaptive value.

And yes understory plants feature iridescence. Here we revisit an old friend of the blog the lycopsid genus Selaginella species name willdenowii. Discussed in this blog post and in this research paper this clubmoss (not a fern!!) shows striking blue iridescence and lives in deep shade.

S. willdenowii. credit Andre Cardosa

Many hypotheses have been put forth trying to explain the blue iridescence of S. willdenowii and other deep shade blue iridescent plants.  Ideas centered on better absorption of red color wavelength light in deep shade but this hypothesis was not shown by Thomas et al. (2010). Instead blue iridescence might offer several adaptive benefits; a photoprotective mechanism that shielded deep shade plants from sudden exposure to full sun; a visual defense against herbivores. Obviously the second hypothesis is of our interest and I will cut and paste the explanation of Thomas et al. (2010).

This adds another interesting wrinkly to the notion of structural coloration used to evade detection. As iridescence can change depending on the angle of the viewer another potential role for iridescence is confusion i.e. what the authors refer to as "making it harder for insects to form a search image". Note that this shimmering - alternatively blending and contrasting with the background - might offer a potential use for a predator as well by confusing and confounding prey - bedazzling them.

Imagine you are an enantiornithine sleeping high up in your roost at night in a large ginkgo. You are among many other birds. Suddenly you wake up detecting movement coming towards you. It is an animal of the same size as the other birds but it alternatively comes into and out of view in a transfixing beguilement of moon reflection and blackness. Your curiosity and inability to form a solid image of the animal is all the hesitation the predator needs. Just as you tense up to fly it is upon you, jaws and killing claws piercing your vitals.

As I mentioned earlier iridescence and what it means for living organisms is very much at the cutting edge of science for things much less long dead ones. But if the present is the key to past...

Here is a cut-out form a very pertinent review article titled Iridescence; a functional perspective


The authors are keenly aware that what can be used to hide prey from predators can also be utilized to disguise predator from prey:



Militaries Study Animals for Cutting - Edge Camouflage

credit LeeRobertsMe CC2.0

The males of the blue morpho family of butterflies use blue iridescence displays that can be seen from up to a 1 km away announce territory. Peter Vukusic, a physicist at Exeter University of England has been studying how the wing scales of these insects influences light waves. He posits that understanding how these scales work is the first step in creating a revolutionary style of camouflage.

"If you know how to manipulate the way light moves and reflects then you can make a surface brighter or darker."

Vukusic sees the potential for developing a type of camouflage that mimics the color of the surrounding environment - the obvious paramilitary advantage needs not be overstated. Vukusic sees tremendous potential in moths, several species of which he states have developed perfect nocturnal crypsis.

Moths have evolved modifications in their wing scales that swallow up light so their wings appear black:

"Instead of multilayers, some types of moth wings have  thousands of tiny, nipple shaped structures arranged in a hexagonal array. If they are really small, half the wavelength of light, then their effect is to reduce reflection from the wings surface" Vukusic says.

Want to go deeper down the wormhole of biomimicry inspired paramilitary technology? How to disappear completely.





And so concludes my little miniseries on Microraptor. A strong case can be made for a highly efficient, nocturnal, cryptic, multi-dimensional predator of small things. Being a predator of small things is no easy feet. Not only are you yourself a prey animal so every bit of time you spend foraging you are exposed to predation but the opportunities for facultative scavenging and usurping easy meals from other animals are diminished. Small bodies lose heat quicker than big ones so that small hot blooded predators need to eat a lot. A small animal predator can't afford to be inefficient. If small felids and mustelids worked with the same efficiency of killing as their larger cohorts they would be soon out of a job. A Microraptor that was a poor runner, poor flyer, and poor climber just would not make it. Instead it was fairly competent in all these realms - and maybe even swimming too (like a dipper). We sometimes speak of the large arch-predators as nature's perfect killing machines but it is really the small killers that outshine the larger ones in just about every metric of killing efficiency. No reason to suspect diminutive dinosaurian predators were any less savvy, efficient, and voracious than their modern ecological equivalents.

Up next I will be looking at a theropod that you may have heard about. A theropod on the complete opposite side of the size spectrum. I will be elaborating on how it was a predator like none we have seen before or since. Consider yourself put on notice.


Papers

Doucet, S., Meadows, M.G. (2009) Iridescence: A Functional Perspective. Royal Society Publishing 2009: April 6. online here

Li, Quanguo (9 March 2012), "Reconstruction of Microraptor and the Evolution of Iridescent Plumage", Science, 335: 1215–1219, doi:10.1126/science.1213780, PMID 22403389

Schmitz L, Motani R (2011). "Nocturnality in dinosaurs inferred from scleral ring and orbit morphology". Science. 332 (6030): 705–8. doi:10.1126/science.1200043. PMID 21493820


"A Long habit of not thinking a thing wrong, gives it a superficial appearance of being right, and raises at first a formidable outcry in defense of custom". Thomas Paine

Here it is folks - the king of all kings, the prize fighter of antiquity, the grand poobah, good ol' sexy rexy himself - as you have never imagined before. Some say that we know more about Tyrannosaurus rex than other extinct animals - or even extant ones - and it is high time other lesser known animals should receive attention. Until recently I was of the same notion. However a new flurry of T.  rex research - highlighting it as an intelligent "super senses" endowed predator - has stirred a quiet but growing mumbling on what it really meant to be the tyrant lizard king. Emerging from the haze of past interpretations a more resolute and astonishing picture of T. rex has been forming in my mind. It is a startling beast quite distinct from past visages but not without a newfound ghoulish and nightmarish quality all of its own. Ladies and gentleman I give you Night Stalker Rex.

credit Robin Liesens

"Now wait a second here" you might be thinking "I have heard about likely nocturnal behavior in T. rex and other theropods before - nothing new here." And you are right, it has been suggested before. Indeed a central tenet of this hypothesis - the specialized detection and predation of sleeping dinosaurs by T. rex - has been at least cursorily mentioned at least once on the interwebz.  But you will not find the idea sold to you with quite the same zest and zeal that you will get from me. And you will not find several new and compelling lines of evidence put forth by me that further leverage and embellish the night stalker rex hypothesis.

To get the cognitive gears pumping I want to address a potential role of nocturnal hunting in a modern day T. rex sized predator - the killer whale (Orca orcinus).


This video is astonishing. What really captures my interest is not so much the explosive action and graphic violence but the more economic questions of foraging efficiency. The pod of orcas has obviously positioned themselves at depth - maybe even partially concealed by features we can't discern from the surface - and execute a precise ambush on a large pod of common dolphins. The orcas - which combined as a predatory arsenal must weigh several dozens of tons with appetites to match - expend much energy, foresight, and effort to snatch up just one small dolphin. For what amounts to basically a hard won "snack" for one orca much less for the whole pod the question arises "how efficient is such a foraging tactic for these massive, hot blooded, predators?" Now that the pod of dolphins is aware of the orcas seems the chance for another capture is remote... Not a great optimal foraging capability for the oceans top predator... Or are we looking at how orcas hunt - or more precisely "when" they hunt - in totally the wrong manner? Ask yourself this: for a predator that utilizes stealth to hunt a very agile and intelligent prey would it not be even more efficient for orcas to utilize the cloak of darkness for better tactical advantage? In diurnal predatory events in orca are we not in fact witnessing the exception to the rule of a generally nocturnal predator?

It is paramount to take heed of the obvious bias in wild orca research. Humans are diurnal. Humans are not marine. Most studies of wild orca will be conducted during the day for obvious reasons of practicality, safety, and ease of observation. Working from a research boat on difficult seas it is patently obvious why the overwhelming majority of wild orca research would occur during the day. Because wild orca are mainly observed during the day and because predation events are therefore only observed during the day the emerging bias becomes reinforcing - Orca are diurnal and do their hunting during the day.

However all may not be as it seems with the blackfish and an emerging trickle of data might in fact point to a more nocturnally active hunter than previously suspected.

By recording vocal activity at night at St. Paul island in the Bering Sea researchers K. Newman and A.M. Springer were able to elucidate not only heightened vocal activity at night in transient marine mammal hunting killer whales but they attributed this to predation events. Not only were calls recorded during the night but vocalizations peaked 1 hour after sunset and were more common from midnight to noon than noon to midnight (keep in mind the long days of the northern summer). Although transient killer whales remain silent during the hunt, after a chase or kill is initiated a flurry of calls commences - which when combined with the nocturnal foraging of the prey animal (northern fur seal) - led the researchers to conclude that nocturnal foraging was very important for these transient killer whales.

Could we be on the cusp of recognizing the importance of nocturnal foraging in many or even most populations of killer whales? The obvious utility of ambush technique shown in the above video suggests that such tactics would only be more adventitious at night, especially for an acoustically sensitive predator. The possibility is certainly there and it is easy to see why a bias of diurnal activity in these animals took root. Such a reversal in our thinking is certainly not without precedent.

Nocturnal hunting in great white sharks was only recently documented overturning the diurnal dogma that afflicted the nature of these fish; spotted hyenas long assumed to be solely scavengers from day time observations but long term studies including night time observation elucidated their predatory nature; and the king of beasts has long been known to be a primarily nocturnal hunter - what is less appreciated is that the male lion - long regarded as the inferior hunter compared to females - can actually hold his own as a nocturnal ambush predator of thick brush.

from here

Game cameras are revealing startling and explosive predatory action that occurs under the cloak of night such as this wild chase and capture of feral pigs by an American black bear - an animal not usually noted for stalk, ambush, and predatory technique.



Hunting dangerous, elusive, and quick quarry by predators under the cloak of night is a time honored tradition. Intuitively this makes sense, better to stalk and ambush prey from darkness. Nothing particularly revelatory about that. However there is a seldom mentioned facet of nocturnal predation that - when your prey is herbivorous - consistently tips the balance of power in favor of the predator. It is an inherent advantage the predator has that the herbivore can really do nothing about. One has to ask the question before one can come to an answer: "Why, if nocturnal vision is so advantageous for nocturnal predators, have not herbivorous prey answered the evolutionary arms race by evolving excellent nocturnal vision themselves? I mean, its not like they have not had enough time to evolve excellent night vision as this nocturnal depredation has been going on for some time likely. Darwinian evolution would almost predict such an advantageous adaptation arising."

The answer to be blunt is that herbivores can not, and likely never have, equalled the superior night vision of their predators because they can't. And it's because of what they eat.

Luckily enough through the power of google search I was able to source this little free preview snippet which I will provide below from Essential Fatty Acids and Eicosanoids: Invited Papers from the Third International Congress (ed Sinclair & Gibson 1992) from none other than the American Oil Chemist's Society:


Vitamin A is concentrated in animal tissue but scarce in plants. It is essential for night vision and because predators have a ready and pre-made form of it they will always have a greater capacity for night vision relative to herbivores. Not because herbivores would not benefit from good night vision but because of biochemistry. Yeah science!! If the present is the key to the past and the same unequal playing field occurred in dinosaurs (no reason to think that it didn't) there was likely a high bias of nocturnal theropods stalking the Mesozoic nights. T. rex - as an obligate hunter - certainly slots in nicely to this realm.

The question then becomes "well if T. rex was a nocturnal hunter what type of hunting strategy did it use?". Various methods could and likely did take place such as ambush  at known prey "hot spots", stampeding prey into confusion, stalking of prey in dense foliage, pursuit etc etc. Long story short I think all of these tactics were utilized during the different ontogenetic stages of T. rex. The more light and leggy youngsters utilizing more athletic, running pursuit strategies morphing into a more stealthy, ambush style predatory tactic with the onset of robust build and large mass.

For this hypothesis I want to concentrate on the onto-morph of the adult T. rex. We are talking about Sue sized rex here. And this is an important distinction because a tenet of this hypothesis is that the hunting strategy of other, smaller  tyrant lizard species was encapsulated in the ontogenetic history of T. rex. Essentially in moving up in size through sprightly large coelurosaur sized juveniles, to Albertosaurus like teenagers, to Daspletosaurus sized subadults the behavioral ecology of these respective tyrants was mimicked. But by the time we get to "Sue" sized adults T. rex was playing a different predatory ball game altogether.

Sue Is A Brickhouse - Built Like an Amazon



First of all time to talk about the elephant in the room when it comes to T. rex. And I literally mean elephant in the room. Sue not only was big, she was a certifiable fatty. Sue was not just a tad bit on the hefty side, she would have in life appeared ponderous and round to an almost cumbersome degree. Seriously T. rex as depicted in paleoart is probably the most shrink wrapped, trimmed up, and "wishfully" sveltely depicted  prehistoric animal of all time. Its like there is a collective denial of T.  rex's true body type. T. rex paleoart is the equivalent of gaining a few pounds (or a lot) and keeping that selfie around on social media from when you were trim. And I am not just discussing fan art or deviantart renderings of T. rex - I am talking about the big name "world renowned" paleoartists. You can take your pick, I say that they all underestimate the genuine "girthiness" of ol' sexy rexy. Not by a little, but by a lot mind you. It's time we embrace the big rex and stop the body shaming denial. Big is beautiful!!

If you want to move towards a more realistic countenance of T. rex draw an animal fatter and more rounded than pretty much all other depictions. Now make that animal 20% larger still!!



Have your doubts? Remember there was that little study published a bit ago by Hutchinson & Makovicky? They found that previous estimates were substantially low and their computer modelling suggested an increase of about 30% pushing Sue up to about 18,000 lbs or 9 tons - and they call this size on the conservative range!!



I got a chance to visit with Sue and talk to her about her self image and eating issues as she recently stayed at the Santa Barbara Museum of Natural History. Let me tell you that song "Brickhouse" (She's a brickhouse, just letting it all hang out") does not even come close to doing her justice.

"Sue" credit Duane Nash

When you really look at Sue - and to a lesser extent smaller adult rexes - once you get past the huge maw, lethal bananas, and overall size - you have to be impressed with that barrel chest. I mean come on now, if you take the perspective of the above photo and add on even just a smattering of integument, skin, muscle, and fat to the torso you quite literally would not see the hips from behind that thick barrel chest!!

"Sue" torso credit Duane Nash

I mean really now, it's just ridiculous. Especially when you compare the torso against other slab chested theropods or even other herbivorous dinosaurs for crying out loud. Go look at the various museum mounts of T. rex mounted in pursuit of herbivorous prey - the degree of roundedness in the torso of rex even crushes the giant, rear fermenting sauropods, ceratopsids, and hadrosaurs it was hunting. While not as wide as ankylosaurids T. rex certainly had a deeper chest than they did. Also compared against the torso of canids, felids, and even ursids T. rex looks unambiguously ahead of the curve in terms of a massive torso.

The real elephant in the room is not that T. rex had a massive barrel chest - that has been known and commented upon for some time - the issue is that no other terrestrial tetrapod predator has such a barrel chest!! You really have to go into the aquatic realm to find such girthy predators, animals that have escaped the burdens of gravity. Obviously T. rex is no whale or aquatic animal - it still had to operate under the confines of 1 G - but I do think it had escaped the traditional limits of what it means to be an agile, cursorial predator. No longer hemmed in by ecological and functional constraints of maintaining high degrees of speed and agility other evolutionary pressures dictated an increase in general size, robusticity, and overall swelling of the tyrannosaurid bauplan. These evolutionary pressures included territorial defense, intimidation of rivals, garnering mating privileges, and storage of fat for lean times. All of these Darwinian benefits would dictate and be benefited by increase in size/girth but only after the evolutionary pressures that necessitated speed & agility were lifted. In other words T. rex only could become the T. rex we know and love after it developed uncanny predatory technique as a cryptic, nocturnal, super senses equipped, arch predator specializing in detecting, infiltrating, and apprehending sleeping dinosaurs.

So how fast was T. rex? 

Obviously this is not a full on review of the research into tyrannosaurid speed. But it is my personal reconciliation of the data and not at all incongruent with accruing data and more coming down the pike suggesting that for T. rex (and probably many gigantic theropods) they were NOT SO FAST (or more importantly agile).

People love to ask this question, and paleontologists love to give eternally "sitting on the fence type answers" - as they should because we really don't know. Not only that but solid, concrete speed numbers on most extant animals is lacking. What I will say is this. Unless Usain Bolt is a secret paleo fan and reader of antediluvian salad, T. rex is probably faster than anyone reading this blog. Now, one statement I hear again and again is that "it does not really matter how fast T. rex was as long as it was faster than its prey". Which on the face of it seems like a reasonable answer, if you are assuming that T. rex was a bit of a pursuit predator and that leg length is a prime determinant of speed. But I am not quite so sold on this line of thinking because there are some notable exceptions - chiefly bears - which constantly fly in the face of the dogma that dictate long lower legs equal high speed.

Based on relative leg length we should expect camels to thoroughly smash bears when it comes to speed...




If both bears and camels were extinct based on comparing lower leg elements the camel would be asserted to be faster. The camel can indeed move pretty fast - indeed I was astonished when actually seeing them get into a full on gallop in the video below - but I would not by any means be confident that in short bursts bears are not just as fast as the longer legged camels.





When it comes to speed in T. rex, its likely prey base, and what it means to be a good & efficient predator I think the questions we ask play a big role in the solutions we seek. When we ask "how fast was T. rex?" implied and embedded in this question is that pursuit was important for T. rex and however fast it was it had to have been faster than its prey base in order to make a living. Instead of trying to get to answers based on the question of speed - which may in fact be a wash when compared against its prey base because of bears and how they break the rules - let us instead ask a more incisive and telling question: "how agile was T. rex?"This line of thinking has more merit to it than simply asking "how fast?"because when you couple the agility of T. rex with the attributes of its prey base there are some significant conclusions to be drawn.

T. rex was horrendously not agile. Indeed it is hard to imagine nature coming up with a design less equipped to handle tight turning. A tall biped, long and heavy all over. Once it gets a head of steam going in one direction it has horrible turning ability. Kind of like running while carrying a big heavy, long log and being asked to twist and turn. Hutchinson (yes the same Hutchinson form the revised mass estimate paper) came to this conclusion when he looked at the turning ability of rex. Ultimately the study concluded that T. rex took a full 1-2 seconds to make a quarter turn (45 degrees).

Past assertions have all resorted to the stock answer that T. rex was "just good enough" to chase down its gigantic prey base are lacking. First of all we don't have reliable speed indexes of modern animals much less extinct ones. The ability of short legged bears to sprint at the speed of long legged ungulates casts doubt on the mere long legged argument to infer high speed. We can't be confident that T. rex was faster than Edmontosaurus, Triceratops, or hell, even Ankylosaurus!?! Short legs, if well muscled and full of bouncy tendon can still do the same job of long legs. But one thing we can be certain of - more than the relative speed argument - is the relative agility index between T. rex and its presumed prey. And here we can see - unequivocally - that T. rex is not on a level playing field with its prey, all of which were quadrupedal with a lower center of gravity and better turning ability. If we combine this with the possibility that some of these herbivores were as fast or even faster (da' bears) than ol' sexy rexy we come to the distinct possibility that these animals could run circles around ol' rexy. Indeed if T. rex was a pursuit predator of gigantic and dangerous prey that could easily outrun, outmanoeuvre, and kill it T. rex would have quickly become erased from the fossil record. An obsolete and inefficient design with glaring flaws that can not be ignored or explained away.



The answer is that (adult morph) T. rex did not chase much of anything down except maybe another T. rex. Ol' sexy rexy eschewed the whole speed game altogether and in doing so achieved both great hunting prowess and great size. It snuck up on dinosaurs both awake and asleep - although sleeping dinosaurs became more of a specialization in larger rexes - under cloak of darkness. The average "chase" was measured in just a few meters or even centimeters. This opened up rexy to exploit not just the large ceratopsians, hadrosaurids, and ankylosaurids that it shared its habitat with but rex could now exploit all the smaller and even more agile dinosaurs it shared its habitat with. A true ruler - a tyrannical rex in every sense of the word - that by highlighting stealth and negating speed it could demand caloric tribute from every underling in its kingdom. Literally nothing was safe in the kingdom of rex - everything from armored ankylosaurids to speedy ornithomimids - could and did end up in the belly of the tyrant ruler king.

I guess I was a little naive in imagining I could get through this hypothesis in just one post. In this post I wanted to concentrate on the unparalleled girth of rex, highlight the fundamental underestimate of rex's size both in both paleoart and technical literature, and show why, if there is any sort of consensus on rex speed & agility, it should be moving in a direction of caution with regards to extremes in both of these dimensions. 

Up next I want to delve into the super senses of T. rex, how to be a giant stalker, and why T. rex had a "childhood".





Refs

Hutchinson JR, Ng-Thow-Hing V, Anderson FC. A 3-D interactive method for estimating body segmental parameters in animals: application to the turning and running performance of Tyrannosaurus rex (2007) Journal of Theoretical Biology vol 246 Issue 4. 21 June 2007 abstract

Hutchinson JR, Bates KT, Molnar J, Allen V, Makovicky PJ (2011) A Computational Analysis of Limb and Body Dimensions in Tyrannosaurus rex with Implications for Locomotion, Ontogeny, and Growth. PLoS ONE 6(10): e26037. doi:10.1371/journal.pone.0026037

Newman, K, Springer, AM. Nocturnal activity by mammal-eating killer whales at a predation hot spot  in the Bering Sea (2008). Marine Mammal Science, 24(4): 990-999 (October 2008)

Zelenitsky, DK, Therrien, F, Yoshitsugi, K. Olfactory acuitty in theropods: paleobiological and evolutionary insights (2009) Proceedings of the Royal Society of Biological Sciences. link

As Khalil Beiting pointed out in my last post T. rex is actually not the only known barrel chested terrestrial theropod. Allosaurus, though certainly not displaying the thickness of T. rex, has a pleasantly plump countenance. And certainly all other tyrannosaurids display a thickened torso to varying degrees. In the case of Allosaurus a highly agile, cursorial nature need not be selected for - giant sauropod carcasses, sauropodlets, and stegosaurids are not winning any foot races. Having a little extra in your back pocket might come in handy for Allosaurus when wrestling teenage sauropods and intimidating/fighting over carcasses with rival mega-avepods. In the case of other barrel chested tyrannosaurids I believe this increasing girth - culminating in T. rex of course - speaks to a general trend of highly sensory adapted, nocturnal, stealthy, territorial, quick killing, and calculating predators.

Of course when I speak of "fat" tyrannosaurus or other theropods I am not implying that they are fat the way a super weaner elephant seal pup is. Obviously they probably carried some fat depending on the season and condition but this fat would be concentrated at the base of the tail, thigh, abdomen and hip near the center of gravity (kind of like a chicken). When I speak of "fat"T. rex& tyrannosaurids I mean that they are coming at you with the thickness. A professional football linebacker or a sumo wrestler are both athletes, are both powerful in any sense of the word, are both athletically gifted in any sense of the word, and they both  are carrying not a little, but a lot of fat. But these "girthy" athletes are probably in better shape than the average reader of this blog and one would hesitate to call them "fat" in the negative connotation of the word if they were within arms reach of you.  It is a bit paradoxical that such large athletes are rarely described as "athletic" even though they perform amazing feats of power and strength. The term "athletic" seems to be reserved for only the svelte, lithe, trim, and quick athletes in the pantheon of "attractive" olympic body worship culture.

pro-baseball player Prince Fielder

It is this bias I speak of - "what constitutes athletic?" - and how this concept intertwines with being slim, of low body fat percentage, and being of a culturally established level of physical beauty and attractiveness. It is this bias, I assert,  that creeps into and underpins our thought processes when imagining what constitutes athletic and attractive creatures of deep time and how they should look.

olympic athlete Holley Mangold

It is my contention that we want slim attractive theropods - especially tyrannosaurids - because this matches what we want to see in our own vaunted athletes. Slim equals beauty, success, athleticism, and adaptive superiority. Fat equals ugly, inferior, sickly, tired, slow, and headed towards the evolutionary dustbin. The notion of fat dinosaurs, especially fat theropods, also strikes a dissonant chord within us because this was the predominant past visage of dinosaurs prior to the dinosaur renaissance. And we all know that the past researchers of dinosaurs (pre-renaissance) got everything wrong, right?

Gorgeous George and some dumb duckbill. credit Archive of Field Museum

Above is the old - and now overhauled - predatory pose of Daspletosaurus dubbed affectionately "Gorgeous George" over some dumb duckbill at the Field Museum of Chicago (special kudos to DinoGuy2 from the dinotoyblog forum for jotting my memory of it). Although I never saw it in person I do remember this image vividly from my childhood. What I want to talk about is not the outdated vertical mount, or the tail dragging, or the pronated hands, or the dubious taxonomic status of this specimen. Go read this excellent write up The Glorious Journey of Gorgeous George if you want to learn more about the history of this mount. What I want to draw attention to is the gastralia in this mount that denotes a very thick and round countenance.



Gastralia are rarely included in mounts, even to this day, and I can't overstate the caveat that skeletal mounts sometimes get it wrong. On the other hand can anyone prove to me that the gastralia as depicted here did indeed get it wrong? As noted in the linked history of this mount the gastralia is not of the original bone. But it looks to be a pretty seemless transition of the gastralia from the pubic bone to the furcula. Based on articulated specimens of other theropods with intact gastralia this should be what to expect.

stolen form some creationist web page

What is interesting, and maybe it is just perspective playing tricks here, is that when we look at the refurbished mount of Daspletosaurus at the Field Museum, Gorgeous George looks like he has lost a few pounds.

Did you lose some weight Gorgeous George? credit Funk Monk CC2.0

It appears that Gorgeous George in his new dynamic posture has received a bit of a tummy tuck. Where  did this tummy tuck come from?

Well if you go back and read Predatory Dinosaurs of the World Gregory S. Paul advocated hollowed out bellies for theropods:

"...theropods probably looked lean, sleek, and a little bony, like big dogs and cats. "Plump" theropod drawings are certainly wrong." (Pp. 105)

"Predators gorge at a carcass, then fast until they are hungry again. The stomach is highly distensible so it can hold big meals. In accordance with this the abdominal "ribs" or more correctly gastralia, of predatory dinosaurs were poorly ossifiied, multijointed, and very flexible. So hungry theropods on the hunt should be drawn with hollow cat- or dog-like bellies. In some of the big mounted skeletons, the abdominal ribs are mounted to form a distended belly, which would be true only after feeding on a kill. A satiated theropod mush have waddled away from its meal!" (pp. 106)

His skeletals follow suit. Go peruse his theropod skeletals, especially of any large bodied forms, and you will note he gives a distinctive tummy tuck to the gastralia just after the pubic bone.* But is there any evidence for such a tummy tuck in theropods? Would the gastralia of a hungry theropod necessarily have formed such a hollow cavity or would a theropod belt - line been a bit more ample? I have not found any preserved specimens and I welcome any evidence supporting such a tummy tuck. Crocs don't seem to have it. I can't discern such a tuck in any of the remarkably complete specimens of theropods... you can connect the dots or the gastralia as you want BUT there might just be a bit of a modern day bias in trimming up theropod skeletals/mounts in some cases. Perhaps the ol' skool look had a little bit more truthiness to it than we might initially presume... I have not noticed the tummy tuck in Scott Hartman's skeletals but I do think his flesh outlines are too svelte.

*I am not suggesting that GSP ignored or misinterpreted data merely that his depiction of tummy tucked gastralia is consistent with his assertion of hollow bellied, svelte theropods.

Things seem a little equivocal on the exact neutral placement of gastralia but there is some work done go here. Instead of gastralia allowing a "tummy tuck" look as GSP asserts Classens advocates a more concave look for theropod gastralia:

"In ornithomimids preserved in situ the ventral outline of the abdominal wall as indicated by the gastralia is usually concave. Although this may be a taphonomic artifact, midventral shortening of the gastralial system would result in ventral movement of the abdominal wall (fig 16 A-C below). The ventral movement of the body wall during protraction would result in an increase in trunk volume"

(from Classens 2005)

Also form Classens 2005 it does appear that in crocs there is strong musculature linking the pubic bone to the gastralia seeminly negating the possibility that such a tummy tuck would be apparent in life. Instead the gastralia likely moved as one functional unit and might not "pinch in" to denote an empty stomach. Indeed if an empty stomach would cause the "tummy tuck" look to appear we should see lots of evidence of this look in crocs since they are ectotherms and often have empty stomachs. But do we see this "tummy tuck" in living crocs? Nope.

Chubster Tyrannosaurus from David Norman's Dinosaur! non tummy-tuck

Svelte Tummy Tuck Tyrannosaurus credit Gregory S. Paul used for educational purposes "don't sue me please"

As you can see adding the tummy tuck has a profound effect on how the rest of the gastralia line up, dramatically altering the profile of the animal. Classens cites a paper by Carrier & Fisher that during gastralial retraction the abdominal cavity could expand 14% in Allosaurus !!

non-tummy tuck T. rex postcard from London Natural History Museum taken from Don Glut

credit Neil Lloyd taken from Love in the Time of Chasmosaurus

Obviously the above image has some glaring issues - but maybe the rotund girthiness offers a lot more truthiness in it than we might be comfortable in conceding?

Where does the truth lie with regards to gastralia placement? Maybe a bit in between the Gorgeous George look and the GSP tummy tuck look? Or is that just a needless compromise? Personally I suspect past "chubster" depictions might offer a shade more truth than the more recent svelte, trim depictions. Perhaps we prefer our theropods svelte, trim,  and "athletic" looking just like we prefer our modern day "athletes" to look with respect to olympic body spartan hero kult skinny worship?

Think about balance for a second. Having the most rounded, heavy part of your body towards the center of gravity makes absolute sense for a horizontal obligate biped, especially one with a big head. Functionally theropods would be more stable in that configuration.

Did I just make all theropods - not just tyrannosaurids - "fatter" or phatter if you prefer? Yeah I said it, every svelte looking, skinny, tummy tucked theropod is OBSOLETE!!   ;')

CutiePie by Duane Nash

Weird enough for you?

Whiskers, of course it had whiskers. A big fat tail base because of the caudemofemoralis and fat storage, of course. Prominent pterygoideus flare just like in big crocs - why not for the strongest terrestrial biter ever?  Obscene tufts of thickened skin around the head, neck, and forequarters - biting into the neck of T. rex would be like biting into a flat big rig truck tire. But probably the first thing that catches your eye is dem big honking toes and feet, enough to give any pedicurist nightmares...


The feet of course are why this post is subtitled "where the rubber meets the road" because it is the feet that take much of the impact of the stresses and strains of a biped the size of a small whale. They would need cushioning - gel soles if you will - and lots of it. More so than is pretty much always depicted. In other words pretty much every image of large theropod feet is - OBSOLETE!!!   ;')

Because the feet of Tyrannosaurus and other - quite literally - mega-avepods have to react to the stresses incurred by high weights we should think about the ol' square cube law. Since volume increases faster than surface area large theropods should have relatively bigger, derpier, and more rotund toe and foot pads than their smaller brethren. Trackways confirm this.

Credit Rufous-Crowned Sparrow. Philmount Ranch new Mexico

There is also loads of examples of large theropod footprints getting confused with large ornithopod footprints and vice versa. Almost like there is some sort of biomechanical constraint imposing limits on the pedal morphology of giant bipeds? Hint, hint there likely is...

Also of note is the reported gigantic abelisaur footprint of recent news that features a positively gigantic foot pad. I have heard some chatter it might be from a sauropod back foot but when giant biped get their foot on it just may have looked like that...

Not only are giant theropod feet bigger, wider, and more plump than generally depicted, the claw itself was likely fairly elevated off the substrate in neutral position with only the tip contacting the ground and perhaps only when it pushed off. Think more like giant dog paws. YW Lee was kind enough to share this purported photo displaying massive toe pads on the feet of Concavenator. I honestly don't know if I am breaking some embargo here or if this should be taken down (let me know if so), but sheesh that padding is incredible.




Anyways make of these pics what you will, perhaps I severely underestimated the amount of toe padding in my illustration?!?

In any case there are good examples from present theropods that have toe pads to suggest that as bipedal terrestrial theropods get bigger the padding on their feet get relatively bigger to compensate for the exponential expansion of volume (i.e. weight).

Compare the foot padding on a turkey to an ostrich:

credit Malcolm Libury. turkey foot

credit Masteraah. CC2.0

For paleoartists wanting to draw large theropod feet with a bit more truthiness: draw them bigger, plumper, more elevated claws, more uglier, and just plain derpier than you see in all other depictions (including any and all "world renowned" professional paleoartists). It is quite interesting why big ol' toes and toe pads have not got a "footing" so to speak (bad pun is always intended) in theropod paleoart.  I have discussed the patently obvious issue of ignoring abundant large toe pads in dromaeosaurids before - which calls into question a tight grasp needed for the RPR model of dromaeosaur predation. We have had evidence suggesting as such for some time via these footprints. But in my estimation only a paltry foot pad is given and never do you see the claws actually raised off of the ground.

Big, gnarly, ugly toes and feet are simply not as attractive and sexy as the slender, refined, and petite toes and feet of modern theropod paleoart. We keep wanting to export our cultural baggage with us in our excursions into deep time.


So back to stalking technique and what big foot pads, chubby toes, and gel shoes meant for T. rex and other large theropods. What these attributes imply is that one of the most iconic scenes from Jurassic Park - the cup of water rippling at the approach of T. rex - is truly and utterly false. Not only that, such a noisy approach is diametrically opposed to the stealth mode that these animals operated in.



T. rex and other giant avepods would have been disarmingly quiet when walking around. Their huge and fleshy toes and foot pads smothering and muffling the sound of any snapping vegetation or substrate that might betray their presence. In heightened stealth mode - when they were actually stalking - they would have moved with the precision and care of a gigantic heron. Students of natural history should immediately think of the commonly observed silence that elephants can move with. An uncanny ability to slip into stealth mode is often attributed to these animals by hunters/poachers/naturalists as they can at will slip into the brush and disappear noiselessly.



Elephants are also useful in providing an example of unequivocally gigantic, stealthy, and strategic (plant) predators that make successful and repeated nocturnal raids on the subsistence farms of hyper vigilant but nocturnally ill - equipped hominins.






When T. rex and other tyrannosaurids were not out performing stealth raid operations at night what were they doing during the day? Probably a lot of lounging around on their big fat bellies, preferably in a morass of cooling mud or body of water like the self satisfied tyrants they were. Probably looking quite ridiculous while doing so. And yes they could lie down just as I depicted below. (Pp 199 Ch. 11 Rex, Sit: Digital Modeling of Tyrannosaurus Rex at Rest Stevens, Larson, Will & Anderson Tyrannosaurus Rex: The Tyrant King).

Cuz bad asses do what they wanna do and they don't care what you think about 'em or how ridiculous they look doing it.

From Amlaner & Ball 1983. encountered here

Sources

The Glorious Journey of Gorgeous George. Extinct Monsters

Classens, Leon P.A.M. (2004) Dinosaur Gastralia: Origin, Morphology, and Function. Journal of Vertebrate Paleontology 24(1) 89-106: March 2004 online

Paul, Gregory S. Predatory Dinosaurs of the World. 1988 New York Academy of Sciences. Sime & Shuster


"A Long habit of not thinking a thing wrong, gives it a superficial appearance of being right, and raises at first a formidable outcry in defense of custom". Thomas Paine

I could have wrote just another hunky dory, look at how happy we are in paleo land, so inclusive and so progressive, color by the numbers write up of my experience at SVP2016 but then I thought to myself "do people really come here for that?"and how disingenuous  would I be in writing such a piece? I would imagine that by now if you have kept following this blog you yourself might be a little left of center; a little bit of an envelope pusher; a little bit of a black sheep. In fact, you might be all those things and still disagree with a lot of what I say - all the better but you have to give me this - I do force you to think. Or you might be someone who genuinely dislikes me and what I have to say but keeps coming back anyways, in that case thanks for the page views.

"This ain't no fucking Bon Jovi concert."

Despite my seeming mockery of Mormonism and religious thought imbued in the title of this post and the blog title itself I do think a certain amount of spirituality or strengthening of the spirit is of benefit to people. A personal, spiritual, and cosmological reckoning of one's place in the universe. Are you walking the path? I do place some attention on "meaningful coincidences" or "synchronicities". I don't overanalyze them or really try to persuade other people of their merit or that they happen to me. I simply take note of them, realize the universe is giving me an "atta boy" and carry on. I also take note of happy accidents. For example upon arriving at LAX I learned the plane was oversold and my seat was bumped - I had no seat! At first they tried to bribe someone off of the plane for a 200$ dollar voucher. I waited. They rose it to 400$ and I quickly swooped on it. I just had to wait three more hours for my upgraded first class seat. Poor me. Upon arriving in Salt Lake City I had covered my travel expenses and had a good rum n' coke buzz to boot! I knew I was walking the path. Such meaningful coincidences probably have no place in "rigorous scientific discussions" indeed many might read this and see it as just another reason to dismiss me... but I bet there are at least some reading this who have met with series of inexplicable coincidences or experienced a sense of "synchronicity" that they can't dismiss. Even scientists.

And it was one such meaningful coincidence that caught my attention in SLC that strengthened my resolve and resolution that I am on the path. There was a break in the talks or maybe it was just a couple of boring ones that I didn't care for. I was walking around the Grand American hotel where the convention was held mulling over my place in the paleo game - something I think a lot of people do. Do my ideas make a difference? should I just concede that no one will take me seriously as a blogger, non-accredited, non peer-reviewed, shoot from the hip, overly speculative, not playing by the rules and somewhat coarse artist? It was with these thoughts dancing around in my head that I came upon a harpist playing in the lounge... yes a fucking harpist. After seeing that I felt the need to get some fresh air out in the real world. As I stepped out of the bubble world that is SVP, cocooned in another bubble of bougy harp playing wankery, I came upon an item that shocked me back to reality and at the same time gave me the perfect contrasting image to the harp playing world I had just stepped out from.


A used intravenous needle with a small smear of blood still decorating it, just lying in the well manicured grass bordering the ritzy Grand American hotel. A poignant reminder that the world can be a desperate, ugly, brutal, and flawed place - even Salt Lake city. The perfect antithesis to the Grand American hotel, harp playing, and the playing along to get along atmosphere of SVP. The question was laid out before me, not literally but figuratively, am I with the harp or am I with the needle?

You can guess which item resonates with me more (figuratively of course)... but as ugly as it is it offers a more resolute and resounding ring of raw truth to it.... "this ain't no fucking Bon Jovi concert."

All right enough of this soul-searching emo crap. I'm boring, dinosaurs are cool that's what you came here for right?

Daspletosaurus neck throttles some dumb horned dinosaur

Ughhh full disclosure, although this is my third SVP I do admit a certain hesitancy on attending these events. It costs a lot; it is usually pretty far away; you gotta take time off work; arrange travel times; sitting in cramped airplanes and speeches gives me back pains; ugghh academic types annoy me a bit; I'm a bit of a weirdo loner and don't have a clique I can do stuff with. But with all that bitching and moaning I invariably leave knowing full well it was worth it. The reason I feel this year was extraordinarily worth it was not just for what I learned, but for several key speeches that bolstered and reinforced ideas I have been arguing for and developing here at antediluvian salad. Coming across independent lines of evidence that converge and intersect with developing hypotheses is always very exciting and vindicating. Sharing such passion is something that I will not hesitate to express on this blog. Because, yes, scientists need passion, excitement, and ultimately an emotional plea in their expressions because, well, other less endearing methods of looking at the world are winning the war for how humans view and interpret the world.

I splurged a bit this year and attended the Morrison formation field trip. Hey, when in Rome, right? Given that the Morrison and it's ecology/dinosaurs is something I delve into on the regular here I thought it right to at least visit the place - given that my travel expenses got taken care by synchronicity event #1 it proved justifiable. I also experienced synchronicity event #2 & #3 when I landed in the van with Joseph Peterson of University of Wisconsin-Oshkosh who is engaged in a pretty intense reevaluation of the Cleveland-Lloyd quarry and shot-gun seat opened up for me. You know I leaped on that opportunity!! So I got to pick Joe's brain a bit about Cleveland-Lloyd and I got to stretch out in the front. Win-win.

Our first stop, after a rather picturesque drive, was the hallowed ground of Cleveland-Lloyd. What a place!! I honestly did not know that there was even a visitor center here with skulls and mounted skeletons. Pretty cool but a bit off the beaten path, if you plan a visit make sure to 2x check its open.



Michael F. Leschin gave a pretty engaging introductory talk on the rough-shod history of the place. I made a rough-shod video to boot:


Joseph Peterson then took us into the two quarry rooms where he gave us a little bit on what his group have been finding:




What do we get from this? Cleveland-Lloyd is a mess. It was a mess back in Jurassic and it is a mess now. It is a sloppy, complicated crime scene in which multiple CSI jurisdictions analyzed the scene of the crime and they did not even use proper collection technique. They trampled over everything and crapped on everything. The researchers and the dinosaurs.

Here are some interesting tid-bits that I gleaned from my visit; disarticulated skeletons with some association; evidence of some orientation of long bones and therefore an incipient current; some bones show evidence of trampling - many do not; some bones show evidence of feeding traces - many do not;   often characterized as a "predator trap" CL is abundant in only one predator, Allosaurus, others are rare; with the exception of Allosaurus most skeletons represent adult morph dinos; charophytes, aquatic algae, are present indicating standing water at least some times; abundant shed Allosaur teeth; heavy metals and arsenic are present and relatively abundant; CL sits next to a much larger lake; eggshell has been found, anecdotally said to have been found fairly commonly, but discarded due to misidentification.

For me, it is possible to discard some hypotheses. The fact that CL sat at the edge of a much larger lake allows us to discount CL representing the last water feature on a drying landscape. It was not a dying ground for dinosaurs seeking water, the lake itself would hold water much longer. I think it also possible to discount the idea that the bones washed into the site. The reason I would discount this hypothesis is: why so many allosaurs? Even if you suggest that there is a potential allosaur nesting site why dead allosaurs of so many size classes? Something was killing allosaurs of all size classes in this area.

Here is my working hypothesis and it is necessarily complex due to the fact that an intersecting  convergence of complex factors may have created the picture coming into focus...

What type of body of water/fluvial or lacustrine system was CL? I think Joe is partially right in his assessment of the site as an "ephemeral pond" in the above video. I do think water flow was just enough at times to create an incipient orientation in long bones, while at other times water was stagnant, and at other times it was bone dry. I think CL represents the terminal entrance of a somewhat ephemeral stream/arundo/wash into a larger lake system. During some years substantial flow would allow charophytes to grow and enough of a current to create some long bone orientation. During drought conditions CL would dry out, creating the condition for dinosaur mediated trampling of bone. We see a complex taphonomic record and clues because the setting was very dynamic.

credit Mark Peters CC2.0

Dinoturbation is a thing and CL might just represent a dinosaur mud wallow. Q: What large animals in hot climates don't enjoy a good mud bath? Answer: None. Of course we should expect that large dinosaurs, especially gigantic naked skinned sauropods would enjoy a cool and refreshing mud bath. We should also not be surprised given the size of the bathers involved that in digging in and maintaining such wallows whole stream beds could be affected. Just look at the type of mud wallows that modern pigs can create and size that up to hefty camarasaurids. Now... imagine if you will a small creek or wash, as it loses velocity going down its channel and it approaches the lake the streambed flattens out. This allows all of the small bits of sediment - the fine silt, muds, and clays - to fall out of the water column. These fine particulate sediments i.e. mud would be the ideal candidate material to attract dinosaurs in for a good mud bath. That skeletons show disarticualtion but some association may in fact be due to the dinoturbation of large bodies churning up the sediment.

Old and ailing animals went to die in a place of comfort. Animals when they are dying, they know it. They want to do it as painlessly and as comfortably as possible just as we do. Hospice care for any large, ailing, injured, or sick mega-dinosaur would have been provided for in a stinky, goopy, comforting, morass of mud. The spot on the landscape that provided them with much comfort during life would see them off in death. This notion of large dinosaurs coming to CL to die is consistent with the dominance of mature sized individuals represented at CL. Even the Torvosaurus and Ceratosaurus are gigantic. From what I have gathered there are few immature specimens except for one species.



Enter Allosaurus. The CL visitor center has a neat display of an Allosaurus skull in between the daunting skulls of the larger Ceratosaurus and Torvosaurus pulled from the quarry. Which begs the question: "what set Allosaurus apart from these other intimidating predators that allowed it such numerical dominance in the Morrison?"What type of magical underwear was Allosaurus wearing? Personally I don't suspect it was a wider, more generalized feeding envelope, I'm not convinced that all of these theropods were not supreme opportunists. Indeed when it comes to the diapsid brain and prey it usually boils down to "can I overpower it?" if yes, then I eat it. If no, move on.  All three species seem pretty well pat on weaponry. For me I suspect that what set allo apart was a more adept, flexible, and efficient reproductive strategy. Allo did not outfight the competition, it simply outbred them. And is that not the dinosaurian way? Dr. Bakker has done much work on Allosaurus feeding sites and his interpretation is that Allosaurus fed its hatchlings at feeding lairs, literally dragging sauropod carcasses across the landscape to feed their somewhat altricial young. As evidence Bakker has noted that teeth of young allosaurs coincide with shed adult teeth - they were feeding on the same stuff in the same area. The idea is evocative. But what is easier and more simple than dragging giant sauropods across the landscape to feed your hatchlings? Bringing your hatchlings to the dinner party. What is even more simple than that is laying eggs at the dinner party - or at least in an area dinner should soon arrive at.

credit San Diego Zoo blog

Could Allosaurus have literally colonized giant sauropod carcasses like theropodian tarantula hawks? Laying eggs at the scene giving hundreds of allosaurus hatchlings a competitive edge via a nice feeding opportunity upon hatching? Given that some weeks/months of incubation had to have happened there is a more practical question of is this lifestyle feasible would the carcass be around when the eggs hatched?... However if there is a certain locality that tends to congregate large dead and dying dinosaurs perhaps just laying eggs in that locality on the likely chance that a body might just show up is benefit enough.

All this speculation aside I will be waiting to see if more evidence of eggs/nesting shows up at CL but I do suspect something different regarding reproductive strategy was going on in Allosaurus that allowed it the competitive edge...

What is the killer? For me any holistic appraisal of CL has to invoke a mechanism for "what killed the allosaurs?" I am not so intrigued with what killed all the other dinosaurs - as I mentioned earlier we might in fact be looking at a long standing dinosaur mud wallow that served as a comforting "hospice care" locality for old dinos on their way out. What is intriguing is that allos are found here in all size classes. I am not satisfied with the answer that they were getting washed in as this would still not explain the predator prey disparity and variety of age classes. I do think that they were here in all size classes, that they ate here, and that they died here. The killer in my estimation is something very close to avian botulism or perhaps a deeply nested Mesozoic theropod version of avian botulism.

Many are familiar with the argument that a "poisoning event" created CL. However I think fewer have actually looked into what types of potential poisoning events match the crimes scene and I suspect fewer still have really investigated avian botulism.



I first came across a likely case of avian botulism while walking around the Santa Clara estuary - a visit I documented in these two posts Life & Death in a Southern Californian Estuary parts 1& 2. If the present is the key to past ( or at least a clue) I can't think of any better culprit than avian botulism to have created the situation at CL.

Ideal Environment. Avian botulism thrives in warm, shallow, oxygen poor water, with abundant protein substrate. CL as an ephemeral pond or dinosaur wallow is well poised to foster avian botulism. That dinosaur carcasses occurred with regularity provides the protein substrate.

Transmission & Hosts. Let's suppose CL hosted avian botulism - how did it infect allosaurs? A large sauropod dies at CL of natural causes. It's drinking water, maybe ingesting some charophytes.   Ultimately it does not die of avian botulism but once it dies the bacterium swarms on this abundant food source. Carrion insects colonize the carcass. The insects ingest the bacterium (Clostridium botulinum) but they too do not die from it. However their bodies do concentrate the neurotoxin produced by the bacterium. Allosaurs arrive at the carcass and consume it. As they consume the carcass they incidentally ingest the insects that have colonized the carcass and in doing so ingest the highly concentrated neurotoxin. Since avain botulism is paralytic disease the allosaurs that become infected go into paralysis at or near the spot of ingestion. They are then either killed by conspecifics or other theropods due to their paralysis and furthering the outbreak. Modern outbreaks of avian botulism can kill thousands of waterfowl. In modern waterfowl they get it through eating of infected fish or invertebrates that have concentrated the toxin. Allosaurus most likely would have got infected through incidental ingestion of carcass colonizing insects i.e. "maggot" type insects as it scavenged.

Now we may never get the hard physical evidence of avian botulism from the fossil record. Sometimes all we have in paleontology are competing explanations... As an explanatory hypothesis I think that the intersection of ideas I have presented here as some resonance - enough to at least store in your back pocket for future reference...

The rest of the spots we went to on the field trip: Fruita, Mygatt-Moore, Riggs-Quarry they were all right but did not offer the type of addicting questions that CL did.

Some pictures:

Mormon Tea the ephedra plant at CL. similar gymnosperms would have lived here in the Jurassic

CL

CL

CL

CL

cryptic desert fern CL

L-R Torvo, some croc,  Allo, Cerato. Scale is sort of hard but that Torvo skull is easily a meter long

Stokeosaurus? and Torvo CL

Some beardo weirdo next to the LOLzy mispelled BrachYosaurus type specimen locality Riggs Hill

some Camarasaurus stuff is in there, really. from Mygatt- Moore

All right, enough playing around as Jr. paleontologist - how about the conference itself?



Well I don't have the time, space, or effort to really give a full run down on the talks and posters I saw. But I do have the time, space, and effort to go into the presentations I saw that dovetailed with many of the developing ideas and hypotheses I present here at antediluvian salad. So yeah, it really is all about me ;') - if you want more of a general run-down and review - check out some of the other blog posts about SVP2016.

Semicurcular Canals, Lifestyle and the Theropod Agility Spectrum

The first talk that really resonated with me was by James L. King who is looking at the anatomy of the semi-circular canal in both extant and extinct theropods as a method to infer trophic lifestyle.


I provided the summary above for your reference and mine. What is not included here and what was discussed at length at the talk is that King did resolve a cluster in morphospace indicative of agile, predatory life histories in theropods. Allosaurus, several tyrannosaurids, dromaeosaurids clustered in this group. Who was the outlier? Who fell out from this grouping? Andalgalornis - a phorusrhacid and good ol' sexy rexy himself T. rex. Long time readers of this blog should recognize that I do have a bit of a history with these interesting and imo often misunderstood predators. In Terror Birds Cometh: A New Hypothesis Unlocking Phorusrhacid Feeding Dynamics & Ecology I vehemently argued against the recent interpretation of phorusrhacids as agile pursuit predators of small game (Degrange et al. 2010) that delivered precise downward blows to the back of the neck of small game from the beak tip. Instead I offered that the bite and ecology of phorusrhacids is most similar to giant scaled up vultures and petrels - they were arch predator-scavengers, not small game specialists. Serrated tongues and papillae - just like we see in modern carcass rendering birds - allowed them prime access to the diverse, ponderous and large paleo-mammals they shared the continent with. If Andalgalornis was indeed a "rabbit killer" we should expect semi-circular canals congruent with other agile, predatory theropods. The preliminary data of King does not suggest high agility in Andalgalornis, suggesting that my interpretation of phorusrhacids as macabre ground vultures on steroids - not rabbit killers - may in fact be the more likely lifestyle for these birds. I would also interject that the likely appearance of these birds - often depicted as fully, feathered, regal, and attractive - was most likely ghoulish, nightmarish and full of ewww factor. People tend to forget that humans are animals too and what disgusts and offends us will likely disgust and offend other animals - such as competitors at the carcass of a giant sloth.


It also should not be too much of a surprise why I think that the work of King so far in showing that T. rex is falling out of the "agile" group of predatory theropods brings a big smile to my face. Now King himself at the talk lamented this fact and felt that some in the audience might be a little disappointed that rex fell out as an "agile - hunter" theropod, I guess the assumption being that if rex was not an agile hunter it was not a hunter at all. However King was certainly not referring to me when he made that comment, indeed  if he glanced over at me during this part of his speech he would have seem me beaming with pleasure. As I have been making the case for in the last couple of posts - the (not yet finished) "Nightstalker Rex" series - T. rex had perfected a unique nocturnal method of prey capture. In T. rex speed and agility were not selected for but instead a super - senses equipped predator that could detect, infiltrate, and abduct dinosaurs as they slept allowed ol' sexy rexy to balloon to preposterous girth and size and exploit the complete spectrum of contemporary prey types and sizes.

The Revenge of the Ugly, Fleshy-Faced, Caruncled, Wattled, Snooded, Nightmare Inspiring Theropod with Flesh Antlers

Now, you  know, I just got to do a little victory dance for this one. Especially since I took my share of criticism for it back when I started pushing this view of theropod facial soft tissue structures: What Do Face Biting Birds - Including Turkeys - Tell Us About Face Biting Theropods? As you can see from the comments this assertion that fleshy facial structures in theropods were widespread and even should be expected was met with a variety of responses - some positive, some equivocal, and some highly skeptical. Now my beef, and my gloating attitude, is not aimed at the people who brought good arguments and points against this notion. Instead, and let me be crystal clear, it is aimed at the people who ridiculed, mocked, harassed, and discounted this idea purely from a place of incredulity, emotional attachment, and group think.


Several parts bear repeating:

"Although the bony feature (frontoparietal fossa) is ultimately lost during avian evolution, homologous vasculature and sometimes carunculate skin remain."

"The frontoparietal fossa reached enormous proportions in large theropod taxa such as Tyrannosaurus, suggesting that theropod dinosaurs may have emphasized the temporoorbital vessels for a physiological role, potentially cephalic thermoregulation, and/or to support soft tissue ornamentation or display structures on their skull roof."

Did you catch all that? Display structures on the roof of the skull? It may well turn out that the skin and flesh derived display structures that I have been arguing for and adorning my theropods with for some time might in fact be on the conservative side!! I should - indeed we should - go a bit further with the extravagance, audacity, and sheer spectacle of theropod skin/flesh derived facial structures. What gives me confidence in this work and its implications is the name Witmer at the tail end of the author list. Lawrence Witmer has, if nothing else, put together quite the cottage industry in churning out high quality anatomically informed papers. Although he is the last author on the authorship his name brand recognition alone should make this topic a worthwhile area for discussion. From what was revealed at the talk; these structures were not muscular insertions as the mechanical leverage was all wrong and no sesamoid bones; lots of vasculature present; homologous structures in other diapsids. I have a lot of confidence in this work shattering how we imagine and depict theropods.

dorsal and ventral view of Allosaurus skull

At the end of the talk Holliday implored paleoartists - indeed he pretty much laid it out there - that T. rex and other theropods with large temporal fenestra and excavated frontoparietal fossa should be depicted with snoods, hoods, and other types of soft tissue structures. He neglected to mention caruncules - seems that everyone hates caruncles - but the point was not lost on me. Indeed I would take this notion of theropod cranial soft tissue structures a step further: if you look at the placement and size of these structures you are left with the observation that there is a lot of freakin' piping available to support soft tissue structures. Indeed what we might be looking at is the potential for soft tissue structures that can be engorged with blood. This could literally create structures - functionally and anatomically congruent with antlers - that would dramatically change in size, shape, and color depending on the mood of the animals. Condors can dramatically engorge the tissues on their head and they don't even have the piping that non-avian theropods did!! A great tool for sexo-social display - especially for rival intimidation/fights over carcasses. I never really bought the idea that the crests, ridges, and hornlets on the heads of theropods were their primary display organs - just too small and lacking in that wow!! factor. Instead bring on the flesh antlers.

Lythronax argestes dorsal view, credit Lukas Panzarin. note large and extensively excavated fossa around dorsotemporal fenestra

Paleoartists need the courage, audacity, and freedom to eschew notions of what a typical theropod "looked like". Indeed this whole argument of what is accurate paleoart and what is fantasy should in part be blown up. Do I expect any of the premiere, commercial, "world renowned" paleoartists to start depicting theropods with diverse and wild soft tissue structures on their head? If history is anything to go by, probably not (I would love to be proven wrong though). Remember, well if you are under 30 you probably can't remember, that when Gregory S. Paul started aggressively feathering theropods it was not like the Doug Hendersons and Mark Hallets of the world immediately jumped on board with him.

Hopefully some budding paleoartist on deviantartist will take the bait and get some inspiration from these rough sketches I put down while waiting at the airport for my plane home. Remember kids, fortune favors the bold!!






Speaking of Gregory S. Paul I could not stop running into him at SVP... I mean like everywhere... even at museums, at the hotel... just another synchronicity? Sort of like when I was in the urinal thinking about asking Bakker about the anomalously high predator/prey ratio of T. rex in Hell Creek and then guess who pops in next to me in the urinal... I didn't have the nerve to get into it with him while taking a piss but I swear this happened!!

For the third and final talk that I want to get into - which also btw let me know full and well that I am following the path - is the one on Limusaurus and its very interesting ontogeny. By now you have probably heard the gist of the story. Limusaurus - a beaked ceratosaur that most likely was herbivorous or omnivorous - started out life toothed. Not only was it toothed it started with veritable face daggers.



Now why is this talk by Shuo Want so important to me? It is not crucial for anything I have put out yet, but for something I will in the future. This ontogenetic change from a toothed omnivorous youngster to an eduntulous, herbivorous adult complete with gastric mill encapsulates quite succinctly a change that occurred in many lineages of dinosaurs - including of course birds. What I will be arguing is that a concurrent soft tissue change occurred as well in this transition from predator to omnivore/herbivore.

I can't spill the beans as of yet but I want to build a little suspense for this upcoming project. And I want you to have fun with it too. The answers are already laid out in front of us, we just have not been asking the right questions. So if you are a person who likes exploring, likes new ideas, is open to new ways of thinking about things I ask you this:

Why grow a beak?

Don't answer too quickly.. let the question stir in your mind a bit. Realize that it is a quite simple question but one which has not been asked or answered in any sort of quantitative or qualitative manner. There is an answer and it is embedded in the fossil and evolutionary history of the animals that did grow beaks and those that didn't.

Just think about it a bit...

Something went very wrong at the North Pole… reindeer, red, Santa getting scalped, Nanuqsaurus, northern mega-troodontids, elf gulping azhdarchids, flesh antlers - it all goes together splendidly!! And flesh antlers… OF COURSE FLESH ANTLERS!! The doom like state of the world address should really inspire me to new heights of bizarrely grotesque disturbing hyper violent macabre grande guignol splendor!! AWESOME BRO!!

Been on a little bit of a break. As you can see from the pic nothing has changed around here… Lots of stuff planned though. But no fucking time. And I do have a rule that when blogging feels too much like work or when I feel that I am putting something out just to put it out, I just don't do it.

Hope you have a flesh ripping x-mas and tear into your presents like that northern mega-troodont tearing into Santa's scalp.

Also I have set up a goal on my patreon page. Once I reach 100$ in monthly support I will begin putting down my pale-fiction vignettes there for patrons to view. Over time consolidated into illustrated pale-fiction. I want to pay various pale-artists to illustrate these vignettes.

This post might piss off a few people… including some regular readers of the blog. But if you don't know it already you shouldn't  come here expecting not to be challenged in some ways!! And sometimes we all - including myself - need the piss taken out of us a bit.

credit Hyrotrioskjan aka Joschua Knüppe

The battle of out times - scales versus feathers. I imagine some epic Lord of the Rings battle in middle earth: scale loyalist Orcs massing against feather nazi elves (feather nazi elves lolz). Various banners of the opposing forces drawn up with resounding battle cries and triumphant bellows of warfare. I paint this picture to obviously poke fun at members of both parties and to set a tone of jovial banter. Cuz it is kinda funny when you step back from it and realize 99.999% of people don't really care... Of course I care and so do my readers but I think discussions would be more fruitful if both factions stood down a bit and realized that there are resounding points that both sides make and, as I will highlight in this piece, there are some points and arguments to be made that have largely been circumscribed in the exchange.

But if you find yourself getting heated while reading this just pinch yourself, and then remind yourself that in a world of of growing nationalism, fundamentalism, misinformation campaigns, cyber-attacks, and frank talks of nuclear bombardment what dinosaurs wore for apparel does not really matter much...




The long running scale versus feather argument, largely played out online and largely converging on theropods (especially T. rex) integument has become mired down into two factions.

The pro-scale minions, seemingly on the defeat and defensive suffering wave after wave of feathered theropod discoveries and to top it off ornithischians with filaments. Most damning of all, Yutyrannus a largish tyrannosauroid with abundant feather impressions over large parts of the body. This and other feathered basal tyrannosauroids creating the valid and likely position that more derived tyrannosaurids also sported (some amount of) plumage. Still the pro-scale contingent has reason to remain vocal. Scale or scutes is all we really have for many lineages of dinosaurs; Carnotaurus; derived tyrannosaurids and even T. rex. Scales and scutes certainly have a big role to play in theropod and dinosaur integument and they did so for the duration of the Mesozoic.

credit Chris Masna

Diametrically opposed to the scale loyalists are the self proclaimed (I kid you not there is an actual satirical deviantart group) ... "feather nazis". Theirs is the grand and exciting enfluffening movement where everything from sauropods to ceratopsids is gowned and strutted with honest to goodness flowing manes of insulatory integument. Feathers for all!! Feathers right down to the base of dinosauria!! What was considered overly speculative by many in the 90's has now metastasized into a dogma all of its own. What the feather nazis lack in outright evidence they more than make up for in passion and online advocacy (shaming?).



A more succinct analysis would be that nothing triggers a scale loyalist like a fluffy T. rex and nothing triggers a feather nazi like a JP stylized raptor.

My main beef with both factions is that they have perpetrated a bit of a false dichotomy. Lost in the garbled rhetoric of both parties is a third option that has largely been eschewed, silenced, or simply ignored. That third option is nekkid skin itself. As I will lay out nekkid skin perhaps highly keratinized or fleshy - the most basal, germinal layer of all - on the head and even neck in many cases is a quite defensible option for theropods and perhaps even other dinosaurs. 

But first I must slaughter some feather nazis.

Now my issue with the "feather nazis" is not one of complete disagreement. I think there is good reason to argue feathers or at least stage one quilly type things all the way back to the origin of theropods or more  basally to stem archosaurs. However somewhat embedded in this suggestion is that such insulatory "protofeathers", "dino-fuzz" or "quilly" type structures are wholly and completely superior to "naked" scutes and scales in terms of insulatory potential. Or just negating the potential for thermoregulatory capacity in scaley structures at all and dismissing them as "inferior" or harkening back to more "primitive" gestalts.

I believe that scale loyalists have really missed or conceded an important argument in favor of abundant and diverse scaley type integument in dinosaurs.  S.I.G.I.L. "subdermal interstitial gridded insulatory layer" an idea I suggested here a while back makes the case that scales, scutes, even osteoderms, have important potential for insulatory adaptions. Here I suggested that small pockets underneath the outer layer of skin in naked hided dinosaurs created an insulatory vacuum sealed layer when blood was withdrawn internally, basically the same concept of a thermos or people insulating their house with bubble - wrap. So I am not so sold that naked hided dinosaurs are a bad thing of lacking in insulator capacity even at small sizes or in cold climates. If certain basal prosauropods sported insulatory coats (no evidence yet) or basal ornithischians  that we know did (Kulindadromeus yes!!) S.I.G.I.L. might offer a reason why this coat was lost and basically not needed in more derived forms like hadrosaurs, ceratopsids, ankylosaurids etc. etc. or maybe never there to begin with!!

No, my main beef with the "feather nazis" is not just a certain arrogance and condescension in their ranks but a certain amount of committing "sins of omission". We should always be careful to consider are we making the best argument or are we asserting what we want. And I don't really care if you are asserting what you want but don't pretend not to be!!

Time to take the feather nazis down a peg or two.

For best effect the arguments of the feather nazis should be read in the voice of Gollum. Like Gollum, whose mind was poisoned by the ring and all that it brought,  the feather nazis have also came in possession of an ancient and powerful artifact - the feather - that has likewise poisoned and twisted their mind.




"But, my precious, feathers protect from harmful UV rays..."

This is true. But it is a bit of a half truth. What it is suggesting is that if it was not for feathers naked skin would be burnt to a crisp like extra crispy Kentucky Fried Chicken. This is simply not true and you know what protects from UV the best... melanin found in feathers and skin. You don't really need feathers to shield from UV rays, simply put melanin in your skin (as nekkid skin birds do already) and the problem is solved.

"Yes but feather have unique insulatory properties that keep birds thermally protected from extremes in heat or cold my precious..."

This is true. But again the assumption is that scales or scutes (esp. as I outlined in my S.I.G.I.L. hypothesis) could not do that job aptly too. Scales/scutes are rather unexplored as unique thermoregulatory organs in their own right and need not be assumed as vastly inferior to feathers in terms of insulatory properties in light of the lack of study on them. Especially if we assume a lower middle metabolic rate, scute and scale having dinosaurs might have done just fine… sort of like armadillos (more on xenarthans later).

A BIG problem in feathers covering the totality of large archosaur bodies in hot climates (read large dinosaurs in hot climates) is the issue of heat exchange. If the whole or most of the body is draped in feathers - which have excellent insulatory capacity - and body heat rises too high there is nowhere to shed this excess heat. Except, of course, by allowing for large tracts of scaley or nekkid skin (as modern birds do).

"Precious, you have forgot about the heat shedding abilities of the avian lung system..."

Ah... the coup argument against large tracts of naked skin or scales for large feathered dinosaurs in hot climates. The problem is that the poultry ranchers of California don't agree with you.

A bit ago I taught traffic school and one of the more obscure laws on the books is one concerning objects that can fall out of a moving vehicle and not be considered litter (absolving one of a $1000 fine). Clear water and feathers from live birds.

Spilling Loads and Damage to Highway.
(VC §§23114 and 23115) It is against the lawto operate on the highway a vehicle which is improperly covered, constructed, or loaded so that any part of its contents or load spills, drops, leaks, blows, sifts, or in any other way escapes
from the vehicle. (Exception: clear water or feathers from live birds.)


Turns out that transporting live poultry requires open air containers in order for adequate airflow and avoiding heat stress. In fact a cursory investigation into the issue of heat stress and birds (just google birds overheat) is rife with accounts of heat induced stress and death.The mighty avian lung system might not be the panacea we assumed it was in terms of preventing overheating. Additionally that turkeys and chicken have both avian lungs and fleshy display structures shows that even with both of these adaptations overheating still occurs. Overheating occurs quite a lot in birds actually. So I would not put much merit in this argument to counter abundant and extensive tracts of nekkid skin or scales.

The better bet for being a large feathered archosaur in hot climates is to clear up large tracts of nekkid skin on the face, around the eyes, the neck, even the chest. Get nekkid. Like Lappet-faced vultures. Or marabou storks. Or ground hornbills.

Pelage Loss: For Some But Not All?

There is one important concession that I have never seen feather nazis make. If insulatory apparel goes way back to the base of dinosauria or even earlier then we must presume that it was secondarily lost in some lineages : sauropods, hadrosaurids, ceratopsids are the most commonly cited potential examples of this. However if we presume that they could have lost their plumage then why can't we do the same for large tyrannosaurids? I don't think it is an argument that the pro-scale loyalists have been vocal enough about. I don't myself necessarily agree with it but I also suspect that tyrannosaurids had a heck of a lot of scale coating and nekkid skin on them.

In fact if people are allowed to have the boldness and audacity to depict "feathered" sauropods (and I believe that they should although I don't necessarily think it likely) they should also be allowed the boldness and audacity to depict a giant, perhaps mainly scaled and nekkid skinned maniraptoran that has lost almost all of its plumage. Developmentally it could happen. Personally I doubt it and I think a wooly sauropod and a mainly featherless maniraptoran are long shots, but if we allow speculation to one extreme why not the other? Boy would that trigger the feather nazis.

The Nekkid Skinned Archosaur 

The argument is rather simple and straight forward. More so than that it is bolstered by the patterns we see in living feathered archosaurs. Go read this excellent online summary from an ornithology class on avian integument

Ye shall know it when ye sees it...

What was once completely scaled shall henceforth be completely feathered...
From the tip of the tail to the tip of the noggin' ye shall know only feathers until...
Conditions henceforth arise that necessitate a shedding of select feathers revealing...
a nekkid primordial skin... rippling, oozing, and stimulating with a lustful passion for display!!

Or to put it another way:

1) Scaled theropod evolves feathers. Not just a few feathers, but a full on coat covering the whole body as evo-devo studies suggest. Because feathers and scales are somewhat competitive developmentally what was skin covered with scales now just becomes skin covered with feathers.

2) Later on certain members of this feathered tribe get big or move to hotter climes or both. In order to shed heat, feathers retract from certain areas - the head, feet, the tail. In certain spots that are prone to impact or abrasion against the ground scales reemerge. This is exactly like the "scaled" feet and legs of modern birds. In other areas the feather retract to reveal nekkid skin.

3) And when modern archosaurs shed the feathers on their head, around eyes, the neck... when birds get nekkid they freaking play with that skin in all kinds of weird and wondrous ways. Big time freaks.

4) Bird skin is thin. If you eat some bbq chicken it comes with the skin. If you order some bbq beef it does not come with the skin. So that when feathers are lost one potential way to toughen up skin is to add more layers, wrinkles and weird growth type thingies. Cancerous looking caruncles and tufts of skin, waddles.

helmeted Guinnea fowl. credit Bob CC3.0

Abyssinian ground hornbill. female. credit Jerry Thompson CC2.0

credit Eric Kilby wattled crane CC2.0

A frequent dismissal of this generous endowment of soft tissue display/thermoregulatory structures onto  non-avian theropods is parroted at me as such:


"Such skin display structures are not that widespread in birds, in fact statistically speaking we probably have not even found a dinosaur with such display structures."
Figure 4. Structurally colored ornaments of a sample of the piciform and passeriform birds examined: (A) Selenidera reinwardtii, (B) Ramphastos vitellinus, (C) Ramphastos toco, (D) Neodrepanis coruscans, (E) Philepitta castanea, (F) Myrmeciza ferruginea, (G) Gymnopithys leucapsis, (H) Procnias alba, (I) Perissocephalus tricolor, (J) Dyaphorophyia concreta, (K) Terpsiphone mutata and (L) Leucopsar rothschildi. A,F–J, reproduced with permission from VIREO; B,C,L, reproduced with permission from Kenneth Fink; H, reproduced with permission from Nate Rice; D, reproduced with permission from Steve Zack; K, reproduced with permission from Tom Schulenberg (From: Prum and Torres 2003).


For starters it is a text book case of bad statistics. While it is true that if you measured the prevalence of naked skin/fleshy display structures in modern birds you would find a fairly low percentage - I would hazard less than 5% of birds if not less have such structures - but numbers without analysis and context is meaningless. What you have to do is look at the likely ecology of dinosaurs and find what birds best match. And if you look at the birds that best match dinosaurs in ecology I would pick the ones that are large (for a bird that would be partridge size), mainly terrestrial or at least feed on terrestrial items, and live in temperate to hot climates. I would not put aquatic birds and passerines high up in ecological correspondence but even some passerines and waterfowl sport naked skin structures. Among the birds I would put forth closest to non-avian theropods ratites, galliformes, "vultures", storks, hornbills, cranes and especially ground hornbills as some of the best matches. Once you start looking at the birds that best fit non-avian theropod dinosaurs ecologically and environmentally you start to see that such nekkid, fleshy, and skin derived display/thermoregulatory features are quite common. Nothing is 100% and not all of these birds fit the bill - but a large enough proportion of them do that we should be highly confident that such displays were at least as common in feathered dinosaurs. More common I would argue because non-flighted dinosaurs could afford heavier skin structures while birds have to be a bit more thrifty in terms of such heavy building material. Also, the compacted lifespan of dinosaurs and hyper-competitive sexual politics of dinosaurs would encourage the elaboration of skin derived display structures on both sexes. Also, and most importantly, because they tend to piss off some feather nazis and anything to take the piss out of them.

Large male Kori Bustard. Gular Display but no nekkid flesh. An important exception to the trend credit David Berkowitz C2.0  http://www.flickr.com/photos/davidberkowitz/5698290596/in/photostream

In fairness there are notable exceptions to this large, terrestrial bird with naked skin/fleshy faced pattern. Biology is after all notoriously squishy and as soon as you push down on something and proclaim "this is the answer" exceptions start to arise. Kori bustards are fully feathered and siriemas only have a little eye patch of naked skin. Cranes don't have loads of fleshy skin derived facial structures but they are highly migratory (remember skin weighs more than feather) and principally temperate.  Far be it to me to insist on fleshy faced, skin display structures on all theropods even maniraptorans - I don't really see that this issue is as clear cut as even I would like it to be. Herons are another group that doesn't fit the trends as they have fully feathered necks and faces. However in their case they need to use rapid neck strikes to catch prey and skin weighs more than feathers so better to keep the feathers for display. Certainly smallish microraptorines types likely had fully feathered faces, or species that lived in cool temperate climes (i.e. Liaoning). But gigantic oviraptorines, dromies, ornithomimids, tyrant lizards, therizinosaurs, megaraptors and other largish coulurosaurs I would really hedge my bets towards such  gnarly skin & flesh derived facial and forequarter display/thermoregulatory structures as fairly common. How far back you want to take such skin derived structures depends somewhat on how far back you want to take feathers in theropods. In other words the evolution of feathers begets naked skin derived structures.

The other point lost entirely on some is that I don't have to speculate about nekkid skin and derived structures - we already have proof.

Pelecanimimus polyodon. How come nobody talks about Pelecanimimus anymore? This is a basal ornithomimosaur and therefore a coelurosaur and therefore feathered. The soft tissue preserved around the head and neck as interpreted by the authors is very telling. No scales present. No feathers present. Instead impressions revealing wrinkles (possibly desiccated caruncles?) of skin lacking integumentary structures i.e. no feathers or scales. A soft tissue crest or flange of skin or keratin on the back of the head. A "pelican like" gular pouch. Just as I would predict and just as we should expect for a good number of feathered dinosaurs in hot climates. Soft tissue structures and nekkid skin. Also Edmontosaurus.

*update Darren Naish (see comment) let me know Pelecanimimus soft tissue interpretations are a bit of a wash. What did I say about taking the piss out everyone (including myself)? Maybe the wiki page needs an update too...

credit Cristian-Milia

Of course if an ornithomimid the size of Pelecanimimus is showing a tendency to clear up feathers for nekkid skin and display structures you can imagine how far Deinocheirus could have taken things...

Let's not to forget to feed the rumor mill. If you dig deep enough there are some accounts of nekkid facial skin on tyrannosaurids and ol' sexy rexy himself. Now I don't want ol' Rexy to dominate this discussion but there are consistent rumors of "plucked chicken" looking skin, bits of skin with reduced scalation and completely naked skin. Feather nazis should rejoice at the notion of naked skin because  as I highlighted earlier naked skin implies it was once feathered and there is likely reduced feathering somewhere on the body. But the sheer amount of retrieved "gila-monster" like scalation does suggest that scales were an important and potentially widespread ectodermal covering for tyrannosaurids. Probably more widespread than in the secondarily evolved scalation of modern birds.



I and a few other artists and thinkers that are increasingly embracing nekkid skin on the head & forequarters of theropods are a threat to both the scale loyalists and some feather nazis. I put scale loyalists in a frenzy because this look completely alters the iconic typography of how a theropod head "should" look - primarily portrayed as a tightly adhering scaled shellac over the theropod skull. And I know I really get under the skin of feather nazis because I argue - based on what modern birds do - that the attractive, graceful, and highly feathered facial countenance as depicted in many non-avian theropods is substantially different than what they have become beholden to.

Some feather nazis deserve to be put in their place a bit because some are guilty of the same crimes that they charge the scale loyalists with. What am I saying? Feather nazis often charge the scale loyalists with being emotionally and culturally clinging to an old outdated 90's nostalgia - the T. rex and raptor of Jurassic Park fame. However from my point of view when I advocate abundant fleshy and skin display features in theropods - inspired by birds of course - who do I get the most push back from? Feather nazis. Why? Even though nekkid skin presupposes a fully feathered ancestral state once you go the path of nekkid skin then you pretty much have to go the path of outrageous skin derived structures. And this completely ruins the fully feathered and attractive plumage depicted on the head of most feathered dinosaurs and calls into question how ubiquitous the "ground hawk" look was for dromies. Feather nazis don't like me for primarily the same reason scale loyalists don't like feather nazis. I call into question a certain look that they have grown fond of. Feather nazis can't outright dismiss me based on an adherence to past interpretations as they can do with the scale loyalists.

Confounding the situation is that many paleoartists give theropods a veneer of feathery type insulation but capitulate to the scale loyalists by giving theropods a scaly head. Why do they do this? If you look at what modern birds do when they lose the feathers on the head all you are left with is naked, not scaly, skin.

So far I have taken it a bit easy on the scale loyalists. That is gonna change.

(best read in an awesome - bro voice, whatever that means to you)

"But, yeah, hey man what about like Carnotaurus it had like scales like top to bottom man. Fully bruh."

Ahh I'm glad we get to talk about Carnotaurus. And it was literally shellacked with scales, scutes, nodules galore. Not a feather to be found. Carnotaurus is indeed the clarion call for scale loyalists  and they should not budge from what it tells us - just as feather nazis should not budge from what Yutyrannus tell us. What I really want to talk about is the face of Carnotaurus because, let's be real, that's what we really care about right? The question I ask is did Carnotaurus - and by extension other abelisaurids - actually have a scaly face?

Yeah I am actually serious when I say this. Carnotaurus may have not had a scaly face, it may have indeed had a croc face.


Skin sections (left) indicate that cracks correspond to epidermal bulges that reach the stiff underlying tissues. Immunohistochemnistry (right) indicates increased cell proliferation (green) within the skin grooves corresponding to cracks. Abbreviations: primary (pc) and secondary (sc) cracks (ep, epidermis, de, dermis, bo, bone tissue). from Milinkovitch 2013

Check out this nice summary piece,  croccrack, showing that the assumed scales on the heads of crocs are actually cracked skin that forms embryologically from the underlying bone pressing against it.

Now, I am not one to lean to fully on the extant phylogenetic bracket to infer soft tissues, and I won't start now, but one of the interesting observations is that no living archosaurs have scaly faces. Birds don't although the wood stork comes close with a highly keratinized face. And crocs actually do not have scaly faces, they have a very tight fitting skin that cracks and creases along defined planes of stress embryologically creating the illusion of very irregular scales. Yep, that was something that really threw me for a loop when I first came across that info on Jaime Headden's blog. But it is true, crocs have scales everywhere else on the body but not on the head. Could this have something to do with better use of ISO's on the snout and head... possibly. Stay posted on that thought.

CC3.0 credit A Stranger in the Alps

It is one of those frustrating aspects of paleontology that the holotype of Carnotaurus supposedly contained remnants of the facial skin but they were prepared away... gripes!!

"Originally, the right side of the skull also was covered with large patches of skin - this was not recognized when the skull was prepared and these patches were accidentally destroyed." wiki citing Czerkas 1997

However there are at least some descriptions available of what the facial skin of Carnotaurus looked like which included bits from the lower left jaw and right side of the head:

"Scalation was similar across different body parts with the exception of the head, which apparently showed a different, irregular pattern of scales." wiki citing Donald F. Glut Carnotosaurus: Dinosaurs 3rd edition

Our first clue is that the "scales" of the head were described as "different" from the rest of the body. Hmmm why would that occur? Does the scalation on a monitor lizard head differ substantially from the rest of the body scales? Our second clue is that the scales of the head were described as "irregular"... where have we heard that descriptor before? Oh yeah, the "scales" on the heads of crocs (actually cracks in scaleless skin) are also described as "irregular". Our third clue is that the skull of both crocodiles and abelisaurids are highly rugose, bumpy, and just gnarly looking. The tight fitting skin that covered the skull was equally keratinized, rugose and just gnarly looking. Our fourth clue has to do with why - adaptationally - would crocodiles lose scales on the head? It might have something to do with allowing better transmission of data to those integumentary sensory organs on the head of crocs. Forgive me for lacking a reference but I thing I came across the suggestion of that idea on Mark Witton's blog once... need further info. Regardless I think it worth further investigation.

Remember when it was common sense that crocs had scaly heads? Why, if we for so long assumed that, is it not a definite possibility that the first impulse when confronted with the preserved facial integument of Carnotaurus could the researchers have not made a similar mistake?

Fucking rad, right? Much props to J.W. Kirby for this Aucusaurus with a keratinized but non-scaly head

J.W. Kirby was nice enough to lend his talents for this depiction of an Aucusaurus with a keratinized mug. I think it works exceptionally well and does a good job of splitting the difference between a wood stork and a croc. Visit his deviantart: KirbyniferousRegret

Am I suggesting that abelisaurids lost the scales on their face to enact ISO's? Nope, although the idea of subaquatic abelisaurids has been toyed with, the swarm of data points towards terrestrial. So I don't think that they had ISO's but I do think that they had especially tactile faces. They had tough faces for sure - highly keratinized - but they also had tactile and sensitive regions, especially along the oral margin i.e. the lips. And I would suggest that they had such tactile lips to better react and position themselves with regard to prolonged and dangerous engagements with prey. Their teeth, their jaws their whole predatory apparatus was set up to bite onto and hold onto prey - not slice through it like the vast majority of other theropods. Dispensing with scales on the head allowed for a more tactile and also tough and keratinized predatorial and cranial adaptation to flourish. And also face biting.

Wood Stork. credit Sandy Sharkey/Great Backyard Bird Count

So if you want to draw abelisaur heads a nice informed speculative venture would be to look at crocs and wood storks for inspiration and add some tough but tactile lips and thickened gums!! I am actually converging on a perception that the upper lips of abelisaurids were very keratinized and did not hang low - almost on the path to lipless crocs. I think, however that the lower lips did hang laterally and inferior with a nice big keratinized gummy mess leading up to the teeth. Go bold and add some flesh antlers and outgroths off the cranial crest as suggested by the vessels on the top of the skull of Rugops!!

While we are on the subject of cranial scale reduction, keratinized skin, croc heads, and rugose skulls it is also interesting to wonder if the rugose skulls of other theropods that lived a very facial - tactile existence such as spinosaurids, unenlagines, other theropods and even pachecephalosaurids and some ceratopsids - may have dispensed with scales and opted for keratinized facial halos. Lots of potential candidates there.

I have some other things to say about scales and the potential loss of scales on the heads of theropods but I'm gonna save than for upcoming posts. Just know that I am not done with you yet "lizard-lipped" theropods...

Scale Loyalists Should Not Simply Concede Kulindadromeus or Psittacosaurus

Another issue I take with scale loyalists is that they simply seem to concede animals like Kulindadromeus and to a lesser extent other quilly ornithischians and possibly Concavenator to the feather nazi hordes in their blitzkrieg conquest. Don't stand down scale loyalists these animals have important stories to tell about scales too!!

credit Tomopteryx CC4.0 Kulindadromeus

Kulindadromeus is the best example so I will talk about this little Siberian maverick the most. Somewhat lost in the excitement about this ornithischian with I think 3(?!) different types of filamentous coverings is that it also had a diversity of scaley type coverings. I think 2 or 3 types of scale coatings. That is an important point not to be conceded by the scale loyalists. Think about where these scales were located. On the tail, the hands, the feet. The areas most liable for temperature oscillations. Scales do have an important story to tell and it likely has a lot to do with thermoregulation and scales remained very important for the duration of dinosaur history.

Psittacosaurus soft tissue reconstruction credit:Vinther et al. - 3D Camouflage in an Ornithischian Dinosaur, Current Biology (2016), http://dx.doi.org/10.1016/j.cub.2016.06.065 CC4.0

The quilly Psittacosaurus was pretty small, lived in a cool climate, could have probably grown a coat of insulating filaments. Certainly other similarly sized maniraptoran herbivores and omnivores in the same environment grew a full coat of feathers. So why not Psittacosaurus? We can rule out preservational bias as an argument so often posited for why feathers are "not preserved" as the Xixian beds preserve feathers/filaments well. This is a dilemma that feather nazis simply ignore by pretty much not addressing it or talking around it. It was scaled and those scales may have provided good enough thermoregulatory benefit that a more extensive filamentous coat was not needed.

An important thought to keep in mind with rear gut fermenting dinosaurian herbivores is that they walk around with big compost bins in their gut. Like compost does, rear gut fermentators release heat. This constant slow burn of heat could have allowed for a more reduced and basal insulatory apparel - scales dominating and perhaps in some instances supplanting filamentous coatings. If we look at scales as basically solar panels such animals could have further supplanted their heating costs by stealing and hoarding energy from the sun and environment. Muscular activity, solar panel scales, rearward heat creating fermentation, blood flow and perhaps a rather low and thrifty basal metabolic furnace could have all combined to create an especially energy thrifty and efficient design. An extensive plumage not really called for. This exceptionally thrifty design would have also begat exceptional ability to dedicate food resources to growth as opposed to heating the furnace, in line with the noted size of many dinosaurian herbivores.

Filaments and feathers may not so much as replaced scales but augmented them in some instances, especially in herbivorous dinosaurs.

Xenarthran Dinosaur: The Further Back You Go, the More Complex Things May Get

I want to end this piece by pointing out where I think we might be heading. We might be heading into a  zone of less certainty than more certainty with regard to integumentary structures in not just theropods but dinosaurs as a whole as well as other beasties like various stem-mammals of the synapsid gestalt that have also been receiving interest as goes soft tissue reconstruction. Now I realize that some might not take much solace in this. But I think that we should really begin to expect the unexpected. Before I let you know why I suspect that the integumentary patterns we might infer based on extant relatives might be a little too conservative let me post this abstract to a rather practical and succinct paper.

Abstract

Danielle Dhouailly, A new scenario for the evolutionary origin of hair, feather, and avian scale. Journal of Anatomy April 20, 2009

Another important read is this blog post from reptilis.net "feathers" on the big, "feathers" on the small but feathers for dinosaurs one and all? by Jura it is a little dated but still packed with some good info, as well as good comment section and further links.

Now, in several points in this piece I have referred to nekkid skin as the basal or germinal layer - that when scales or fur or feathers are lost what remains is pure skin. This study confirms that "inhibition (of the Wnt/beta-caratin pathway) leads to the formation of nude skin and is required for that of corneal epithelium."Which is pretty much what I have been suggesting happened quite a lot in dinosaurs that were formerly completely feathered but then - for a multiplicity of reasons - lost such feather coatings on parts of the head and potentially forequarters.

A more interesting bit of info from this abstract is the notion that - read modern - mammals and birds have ectoderm primarily programmed to grow feathers and fur respectively. Again, I want to reiterate that this is how modern bird and mammal skin appears to be programmed. But let us not assume that more basal (read extinct) forms were as hemmed in developmentally to form such structures. I first came across this notion in the above Jura post on the topic (feathers for one and all?) and there Jura  referred to as a basic rule of thumb in the comments section: the regulatory pathways, the developmental constraints may have been a lot more lax and prone to slippage, reversions, and wholesale jumbled set ups than what the more modern derived and somewhat set in stone representatives would suggest. A lot more play. A lot more complexity. And a lot less certainty for anyone trying to arbitrate what is accepted and reasonable in paleoartistic representations.

Pink Fairy Armadillo. credit cliff1066 C3.0

Consider xenarthrans - the strange and alluring mammals that include the extinct glyptodonts and giant grounds sloths, as well as armadillos, sloths, anteaters, probably some other weird ones too I am forgetting. I don't like to use the term "living fossil" but I think it fair to call these mammals the least derived or most basal among extant mammals. The most basal mammals but also the most diverse in terms of integumentary structures. Think about the weird scutes of armadillos and glyptodonts, the coarse hairs of anteaters, the osteoderm studded skin of giant ground sloths. Now in light of what was discussed in the last paragraph where I made the point that the most derived members of clades are "locked into" defined developmental pathways for respective integumentary structures. For extant birds this is feathers for mammals it is fur. But if you go further back into more basal forms in each group it is very probable that there was a  lot more developmental wiggle room, a lot more play, and a lot less capacity to fully predict what was going on in terms of how much, where, and what type of integumentary structures were going on. Consider monotremes, also very basal and also diverse in terms of integumentary types. Pangolins and aardvarks as well.

Now, this is an area of needed study but in light of the basal nature of these animals and the breadth of integumentary structures that they evince I doubt it merely a coincidence that we see this congruence. That pangolins, monotremes, and xenarthrans showcase more diversity in integumentary structures than more derived and numerous ungulates, carnivorans, and rodentia combined is something to think about...

This notion that using highly derived extant relatives to ascribe dogmatic rules to their extinct relatives should not sit too well with both feather nazis or scale loyalists. And you know I like it when both sides of the divide get befuddled. That creates fertile living and creative space to speculate to truly bizarre and jarring amalgamations of quills, feathers, scales, scutes, keratinized skin, wattles, caruncles, frills, dewlaps, and other structures.

In fact we don't have to speculate. Kulindadromeus spells it right out for us being fairly basal and hosting a diversity of scutes, overlapping scales, and various types of filaments. Later ornithischians may have largely dispensed with pelage and just as derived modern birds and mammals are locked into a pathway of fur or hair more derived ornithischians became more and more locked into a developmental pathway of scales. You simply don't see derived ungulates with lumps of osteoderms in their skin do you? And while the maybe - maybe not ulnar quill nodes of Concavenator get most of the attention for that fantastic beast less widely reported is the unexpected diversity and size of large scales preserved with the body. The Mesozoic may have been rife with complex amalgamations of scaly, scutey, quilly, nekkid skinned, and feathery beasties. Enough to confound dogmatists on both sides of the aisle.

Its not about "the enfluffening" or the return of the retrosaur it is about the advent of the weirdening and we have been in it for a while now.

In summary both scale loyalists and feather nazis bring important points to the table but their rigidity sometimes veers into dogmatism.

Naked skin on many formerly fully feathered theropods is a thing, as evinced by Pelacinimimus. The reasons for clearing up naked skin on theropods (extinct and extant) is not fully understood, doubtless multifaceted, and as shown by species such as Kori Bustards and Siriemas not a 100% mandate or law. But it was a trend that was certainly common. The evolution of naked headed theropods depends in large part on how far back fully feathered dinosaurs goes. Whether or not tyrannosaurids sported naked skinned heads is up for grabs but a distinct possibility. Especially considering the tactile nature of their skulls, feathered pedigree, and several anecdotal records of scaleless or almost scaleless hide as remarked by several researchers (Phil Currie & Paul Sereno).

Because bird skin is so thin we should expect that when feathering is lost it should thicken up with wattles, caruncles, fleshy outgrowths, keratinized bits, and other diverse features we see in living naked faced birds. Expandable gular pouches, snoods, crests, and other features were also likely widespread. I would venture that these features are relatively more common in feathered non-avian dinosaurs than flight capable birds because 1) skin weighs more than feathers so flighted animals will tend to be a bit more thrifty with such features compared to grounded animals 2) the hyper competitive, hyper condensed mating politics of dinosaurs would stimulate outrageous, expensive, and elaborate features. Dinosaurs - unlike sea turtles, crocodilians, and long lived monogamous birds species - simply did not have multiple decades to make their reproductive mark. Instead the stakes were high to make their mark when they could and for many species had much less than a decade of good potential mating years. For large and combative males this opportunity may have been substantially less.

Abelisaurids - and by extension perhaps spinosaurids, unenlagines and several other rugose skulled dinosaurs - may have dispensed with scales on the head partially or completely and sported a tight fitting shellac of keratinized skin. Convergent in design with crocodilians and wood storks such a design would offer durability and protection while potentially allowing sensitivity for animals that explored their world largely through their heads.

Much to the consternation of both scale loyalists and feather nazis the more basal we go in many dinosaurian groups the more anarchic and varied might be the integumentary structures. In derived forms feathers or scales seem to predominate the ectoderm in various lineages. In maniraptorans it is feathers, while in ceratopsids, hadrosaurids, and abelisaurids it is scales. However in more basal forms of each group we might expect a veritable riot of weird, diverse, and unexpected integumentary coverings. This prediction is met by the rich and varied ectodermal topography of Kulindadromeus, the potential for both quills and diverse scales & scutes in Concavenator, quills and scales in many ornithischians, and the noted diversity of outgrowths in many basal mammal families today such as xenarthrans.

In short there is a lot to learn. Both scale loyalists and feather nazis have their role to play but I think we might be converging on a world where both sides are too dogmatic and that nekkid skin has a role to play in this as well. As well as keratinized skin. And funky jumbled up, mish-mashed piles of xenarthran like dinosaurs with piles of scutes, filaments, quills and other things galore. For those that like precise laws and set in stone didactic guidelines on how to depict dinosaurs - especially earlier more basal forms in which the developmental pathways were not yet established rigidily - probably not a pleasant time for you right now. And people of such mind sets will probably find greater and greater consternation at the sight of increasingly odd and bizarre dinosaur reconstructions. SUX2BU.

Ok, ok are you still with me? Have I done a good of enough job in triggering scale loyalists and feather nazis? Ok time to trigger myself a bit and it is the consistent critique I always get from some quarters regarding fleshy, hangy things or big lips jutting off the faces of theropods - especially toothy ones. triggrd

"But precious, such features would get snipped right off?!?"

I'm triggrd.
And this is my final word on this.

1) Don't underestimate how tough and flexible skin can be. Chewing on the wattles of a theropod could have been like chewing on a flat tire. You won't really hurt it and you might compromise your position allowing for a more devastating counter strike to the back of the neck, throat, or belly/cloaca.

I really like the thickness, elasticity, and well toughness in J.W. Kirby's depiction of SANTAnaraptor below... they look like tough chew toys that would stretch out and cause frustration to anything that bit into them.

SANTANAraptor  credit J.W. Kirby

2) Critiques of soft tissue display/thermoregulatory structures on toothy theropods should familiarize themselves with the the "handicap" hypothesis of social-sexual signaling structures. In order for a signal to be true and just it must impart a cost on the signaler. That the signal actually imposes some maladaptive traits on the signaler is actually a good thing. Such signals represent the "conspicuous consumption" of the animal kingdom. They also should be expected in animals in which the stakes are high reproductively. And the stakes were definitely high reproductively in dinosaurs. They did not have several decades to make their mark in the Darwinian sweepstakes but only several years. In the largest and most combative large theropods how many years would you expect a large male to reign supreme? 2-3 years? Dinosaur sexual politics was a wild and wooly world, not for the feign of heart.

Also don't be carnivore biased. If you can accept fleshy, hangy wattles, dewlaps on ornithischians, herbivorous theropods, and sauropodomorphs but not on predatory theropods you are being biased. The giant beaks of ornithischians, ceratopsids, the powerful beak and jaws of an oviraptor, a macronarian are not to be trifled. These animals could easily rip your limbs from their sockets and could do the same to any fleshy display device. Should we eschew such devices on all dinosaurs then? - clearly not. In fact Edmontosaurus and Pelacinimimus prove that they had them!!



3) Male bull elephant seals and hooded seals engage in epic biting battle yet maintain fleshy, vulnerable facial outgrowths. Elephant seals form huge colonies... at least some maniraptorans did too. Male elephant seals have a severely limited time to get to the top of the social heap and mate. Theropods - indeed probably all dinosaurs - did not live as long as crocodiles so they were likely under the gun to achieve mating success at any cost. Male southern elephant seals are the largest mammalian carnivoran of all time. Now that is not stated enough in my opinion. The largest mammalian carnivoran of all time is not from the Eocene, Miocene, or early Pleistocene but living with us on earth right now. And it engages in absolutely vicious face biting prolonged skirmishes. And it has the size, strength, and tusks to do some real damage. Just like theropods did. Yet this animal - colony forming, combative, multi-ton largest carnivore ever - it has big, fleshy pendulous display structures right there on the tip of it's face. And you know that sometimes it gets ripped into, indeed it is a bit of a liability in fights but to be a true signal, to evince handicap, to resonate intimidating sounds and visually stimulate opponents - evolution has eclipsed these liabilities and favored large, fleshy pendulous things on the face of an animal that should rightly have them yanked right off. But it has them anyways and most likely did toothy theropods.



And finally - inb4 criticism - highly perceptive and critical reader will have detected what I have done here. By highlighting the need of scale loyalists to look at insulatory and thermal potential in scaley dinosaurs and by suggesting nekkid skin as a kinda proxy for a formerly fully feathered condition, I have deftly played both sides of the aisle and bolstered my claims of 1) S.I.G.I.L. i.e. insulation without feathers and 2) a fairly common evolution of facial nekkid skin and nekkid skin structures in feathered theropods. Duane you self serving bastard!!

Bwa, Ha, Ha, Ha (evil cackle from bowels of paleo - dungeon) stroking my pet cat. "You don't know my paleo super - powers!!"

Scale Loyalists and Feather Nazis recant and end your evil ways and you may yet enter the SKINgdom of Heaven!!

Cheers!!

Let's dive right in shall we? Some of my more persistent readers may have caught onto my none too subtle hints that I have been dropping with regards to non-avian theropod lips. Indeed, I first made the proclamation that "I'm coning for you next lizard-lipped theropods" back during my now infamous posts on sabertooth predator oral soft tissue anatomy. While the extent and applicability of soft tissue covering on the various and diverse varieties of sabertoothed predators is still an evolving and contentious issue my main goal - that we at least now have the space to talk about such issues without ridicule - I feel was achieved. I might have the lost the battle for fully sheathed Smilodon but I won the war for a more free, open minded and multifaceted debate for novel soft tissue oral anatomy in all saber toothed predators.



"No one cared who I was until I put on the mask."

What lies behind the keratinized edifice of the beak? What secrets will it betray…

A frequent theme and constant source of needed intellectual dismantling in this blog is the perpetuation of false dichotomies.  Regular readers will note that I have went up against false dichotomies in my various posts on Spinosaurus locomotory methods (belly sliding and bottom punting versus obligate bipedalism/quadrupedalism and ill-equipped swimming) and most recently highlighting naked skin on the face of theropods as a viable alternative to the hemmed in scale/feather extremes. Similar to the feather vs. scale debate the lip debate has become hemmed into two fiefdoms: the croc-like keratinized oral margin and squamate like lizard lips. As I will address in this and subsequent posts the croc-like keratinized lip and lizard lip gestalts likely occurred in some theropods. But far more prevalent - especially on some of the more well known theropods - is a completely different and novel lip design that I will be arguing for.

The "lizard lips" hypothesis rests fairly squarely on the presumption that non-avian theropods had scales on their face right up to the oral margin. However in my last post I attacked this notion, noting that modern aves lack scaled heads and even crocodiles lack scaled heads.  While I do think some theropods had croc-like keratinized oral margins and some basal theropods likely had squamate lizard like lips, regular readers will know that I have been  dressing my theropods in a unique oral fashion for some time now. I want to in fact give this unique theropod lip design - the third option I alluded to earlier - a name, and in typical antediluvian salad fashion the name does poke fun and have a certain mischievous, provocative and subversive appeal: meat curtains.

Kill It With Fire!! Monolophosaurus displaying its meat curtains. credit Duane Nash

Maybe some of my younger readers are naive to the term "meat curtain" but, well, inquiring minds will find out. Let's just say the term "vagina dentata" has brand new and startling meaning: this pussy bites back!! The comparison is apt because in both vaginal lips and theropod lips ; a loose seal was maintained; the tissue was non-muscular; the tissue was tough and elastic; and the tissue was highly enervated and extremely sensitive with blood vessels and nerves. In addition you have the double entendre of "meat curtains"; it was literally curtains to any meat that fell between the lips of theropods. This set up also has some vague similarities to mammalian carnivoran type lips. However, I must stress that I am not implying some sort of muscularity to such lips. The upper lips just sort of hangs there and plops down on top of the droopy lower lip when the jaw is shut. An oral seal is achieved, teeth are obscured, the upper teeth do not cut into the lower lips as would be in a problem in many theropod depictions.



In the rough coronal anatomical schematic above you can see how this lip design works and is consistent with theropod jaw and tooth anatomy. The nutrient foramen on both the dentary and mandible feed and enervate the lip tissue. A certain amount of tooth crossing is implied allowing the diabolical theropod "scissor cut" technique. That theropod teeth did cross past the lower teeth is probable and rarely appreciated in most theropod lip depictions. Indeed the manner in which most theropod lips are depicted would have the upper teeth shred the lower lips and gums. This is not an issue in the above design.

This model of Allosaurus at the Fukui Dinosaur Preferctural Museum of Japan stumbled upon a similar design albeit I would prefer no snarl and less scales:



That the upper teeth went past the lower teeth somewhat is supported by the patently obvious observation that the neuro-vascular foramina on the lower jaw directly correspond to the length of the longest teeth from the upper jaw. The foramina on the lower jaw in fact demarcate the extent to which the upper teeth slid past the lower teeth and rested against the lower jaw. Alternatively the foramina on the upper jaw simply line up along the alveolar margin of the upper jaw.

Giganotosaurus credit OldEarth

What's my name?

The pattern of foramina is very consistent across many lineages of toothed theropods. In the upper jaw foramina come right up against the oral margin. In the lower jaw foramina mirror the extent and interplay of tooth depth from the upper jaw. This pattern is exquisitely brought to light in the below picture from Jaime Headden.

credit Jaime Headden

These foramina are not just haphazardly placed along the jaw as should be expected if they indeed had a croc - like oral margin. No, tissue was growing out from these foramina. In the upper jaw this lippy tissue - possibly fairly rigid and even somewhat keratinized - just sort of hung out draping over the teeth. In the lower jaw the lippy tissue did not form a pocket but instead grew out somewhat laterally and hung inferiorly. This sort of saggy, droopy lower lip allowed the upper lip to just loosely drape over it but also provided great tactical support for feeling, sensing, and reacting to struggling prey in the jaw. The upper and lower lip combined to form an extensive neural net.

Note that the lippy tissue allows substantially more tactile and proprioception than either the lizard lip design or the weird baggy "tooth pocket" design that has recently come into vogue. The nerve pads of felids and sensitive muzzle/lips of canids are especially useful for allowing tactile information for these animals.


This tactile ability of the lips came in handy not just in securing and maintaining prey within in the jaw but also potentially safeguarding the predator from injury. Theropods did not just eat harmless sauropodlets all the time, they bit into some pretty strong, feisty, and retaliatory animals, including other theropods. One of the persistent myths that has become somewhat enshrined in theropod folklore is that theropods could literally run up to large prey and, almost effortlessly, carve out long and deep gouges with minimal contact. The thick hides, nodules, and osteoderms of many dinosaurs argues against such quick and effortless interactions. In order to deliver a devastating bite the prey may have to have been engaged for longer than generally appreciated. Biting such animals was dangerous and large lips could have mitigated risks. Large and tactile lips could have served as an early warning device when the animal within the jaws was tensing for a blow or other damaging movement. Having lips that could sense such movements and struggles better allowed theropods with such lips to react and counter such movements. Or, if the stresses were too strong, abort the bite. Remember many theropods had a good chin but they had glass jaws. They could take could dorsal ventral blows and trauma but a lateral blow could have been devastating.

"What about such floppy lips getting cut up during jaw closures? Wouldn't they get cut to ribbons?"

If you look at slow motion video of dogs biting the upper lips actually don't have to be pulled back by muscular action to prevent teeth biting into lips. Actually what looks to be going on is that the momentum of opening the jaws throws the upper lips up and away from the point of impact. Additionally, even if an accidental bite of the lips occurred such structures are very tough and heal quickly. A non-avian lipped theropod throwing open its jaws and biting would have looked vaguely canid like but still kinda alien looking.


                                          






Incidentally I do think lips getting cut up is a big problem in the "tooth pocket" design most notably implemented for T. rex in the game Saurian. What is preventing such a loose, non scaled lower lip from  flopping inwards during the bite and getting penetrated? Scales might offer more structural support but if the face was not scaled? I know komodo dragons are often asserted to feature this "tooth pocket" design but is that what is really going on in that mouth? Do komodo dragon teeth actually slide past one another for a true "scissor bite" or do the upper and lower teeth not really cross during the bite sequence? What is all that gummy tissue doing? (hint I will more into komodo dragons on a future post)

In discussing this novel lip structure I like to discuss the genesis of an idea because that is something I always find interesting. Let's revisit the "Hellhound Rex" picture that started the ball rolling for me:


The image disturbed a lot of people, some really rallied against it. That was the clue that I was onto something... and it is not that I think "this is how rex looked for sure" indeed, the best critique I got was from Jaime Headden who, to paraphrase, told me to concentrate on one or two soft tissue structures instead of such a plethora. Admittedly I did take a "throw a bunch of shit at the wall and see what sticks approach". What I think got underneath a lot of people's skin is one specific part of the oral margin. Something that quite happened by accident but which stimulated a kernel of an idea in my head. In other words, something did stick.


You have seen such morphology before. In fact it is directly reminiscent of the rictus in modern avian theropods. It is the rictus that is most often referred to as the "lip" of modern birds and could it be a sort of evolutionary residue? a relict structure from a formerly lippy pedigree of non-avian theropods? Certainly the picture below suggests that rictus tissue can be co-opted for display purposes. Which also suggests that lippy structures in non-avian theropods could have also been co-opted for display purposes.


Theropods - at least those giving rise to beaked birds - likely once all had lips and the evolutionary residue of a formerly lippy dynasty still persists in modern birds in the rictus at the convergence of the upper and lower jaws.

Steppe Eagle (Aquila nipalensis orientalis) credit Quartl CC3.0

In order to illuminate and bolster this claim that meat curtain, quasi-canid style lips occurred in non-avian predatory theropods I am going to go about it in sort of a round about and non-traditional way.
It relies heavily on the principles of convergence and exaptation - two increasingly robust paleontological concepts. The way and manner to ask and investigate the question of why grow a beak is by investigating the fossil record of the beaked and the non-beaked among terrestrial tetrapods. Upon investigating and then illuminating the patterns encountered then offering explanatory hypotheses on why and how these patterns emerged, answers will start to emerge from the fuzz. As I will argue embedded in the question of why grow a beak? is what type of lip was there before the beak?


The Beak Impoverished Kingdom of Synapsids

Let's start with synapsids - mammals and the various stem mammals. They suck at growing beaks. Let's discount beaked whales of course - not too sure if they have true rhampotheca anyways and we are limiting our discussion to terrestrial tetrapods. I guess it is worth mentioning the platypus and some interesting work on the evolution of its "bill" but again that hardly constitutes the keratinized rhampotheca we are talking about.

So why so beak impoverished, furballs?

I will venture it probably has a lot to do with lactation and suckling - that nested quite deep in mammals and maybe even stem mammals is the ability to form a tight seal on female teats/other organs of "nursing" that was advantageous for such feeding.  This in turn begat a very muscular and evolutionarily flexible oral margin. I'm sure that this idea has been suggested before just not sure where or by whom.

We will revisit mammals upon discussion of other beaked animals but just keep this in mind. When mammals make the transition to herbivory or delicate and precise foraging techniques they pretty much universally invest in more intricate and elaborate oral-facial musculature. Think elephant trunks, tapir noses, or even the prehensile lips of bears.

credit Anna Schultz. CC3.0 Tapirus terrestris flehmen response

Prehensile lips and trunks - these are structures on the opposite spectrum from relatively immobile and non-muscular beaks. Yet both extremes can achieve a lot of the same goals ecologically. Both muscular lips/trunks and non-muscular beaks can do some very dextrous and agile manipulations. Keep this thought in your back pocket.

credit Mojcaj CC3.0

To really come up with a beaked dynasty in synapsids we have to go way back to dicynodonts. These stem mammals are truly beaked but their relatively less derived position also begs the question: Did these stem-mammals even lactate/nurse their young? Seems doubtful or, at the very least, painful. This observation supports the earlier contention I made that muscular mouths/lips/oral margins in synapsids has a lot do with suckling.

edentulous upper mouth pad of domestic cattle. credit Woolshed 1 blog

The roughened and sometimes edentulous oral pad of many mammalian herbivores comes the closest to approximating a beak. But even here not quite a beak.

Over all though the lack of beaks among synapsids - especially derived mammals - is notable but there are good hypothesis to explain the dearth of beaks.

The On Again Off Again Beaked Diapsids

It's really when we get into diapsids that some interesting patterns emerge. Forgive me for using somewhat generalized and familiar names (as i usually do) but this is only for ease of understanding at all levels.

Turtles - always beaked. Probably archosaurs or archosaur cousins. Used to have teeth and beaks but have been eduntulous for some time. However it is worth noting that even after beaks evolved in turtles teeth were not totally lost, this is a concept that I will revisit later on..

Crocodiles - never beaked. Crocodiles figure prominently in the lip debate as well. What is noticeable is that various stem crocs engaged heavily in omnivory/herbivory/insectivory. However unlike the case when theropods became engaged with these lifestyles this move from carnivory to herbivory did not result in beaks for any known crocodyliformes. I will suggest that there is potentially a difference in oral anatomy, i.e. lips the presence or absence there of, that negated a convergence in evolving beaks. Again keep that factoid in your back pocket - crocodiles never evolved beaks even when they switched to an omnivorous/herbivorous diet.

Lizards & Snakes - never beaked. This is an important observation that should not go unstated. Snakes are of course dedicated predators. Lizards on the other hand have experimented with all manner of foodstuffs. However even herbivorous lizards don't grow beaks and become edentulous. They might "tighten" up the keratizined scales around the oral margin but they don't form a true rhampotheca and become edentulous. I will go more into lizards in a bit but the patently true observation that lizards - which by definition have "lizard lips" - never evolved beaks but theropods - asserted to have lizard lips - often evolved beaks.

Sauropods - never beaked. Despite spurious claims of a "beak" in Camarasaurus - which is most likely just highly keratinized scales along the oral margin - there are no beaked sauropods. This is an important observation. Indeed if there is one dynasty of herbivores that begs to have beaks it is sauropods. They live by the motto of bite quickly, don't chew, and swallow so an eduntulous beak would have been perfect for them. Yet in over 140 million years of evolution beaks did not occur in this group and they kept their teeth. That sauropods, like lizards, never grew beaks hints at a commonality in the oral margin in these two groups. Sauropods were, and likely always were, truly lizard lipped with a tight band of scales all the way up to the oral margin.

*Ornithischians - always beaked!! (work in progress)

Pterosaurs - sometimes beaked!! (work in progress)

Crurotarsi - maybe aetosaurs, although might just be a highly keratinized snout? otherwise not much beakyness. (work in progress)

Dinosauromorphs - Did silesaurids have beaks…. hmmm. (work in progress)

*these sections are still works in progress and thinking things through...

"Lizard Lipped" Theropods? Lizards Fail Where Theropods Prevail

Lizard Lips in Theropods a Work of Fiction? Ol' Skool Lizard Lip Carch Shark Cage by Duane Nash

Green Iguana (Iguana iguana) credit Bjørn Christian Tørrissen

The thought dawned on me while driving to work one day. If theropods did indeed have lizard lips we should expect convergence in oral anatomy when dietary changes occur in these respective lineages. In non-avian theropods the transition from a carnivorous diet to an omnivorous-herbivorous diet is commensurate with an increasingly edentulous and beaked oral set up. However when lizards - which by definition are "lizard lipped" i.e. a  somewhat tight, keratinized, and scaled oral margin - transition from a carnivorous or "faunivorous" lifestyle to omnivore and herbivory they never evolve beaks. Never.  Nunca. Not Once. Most obvious are iguana but you have various member of the agamidae such as Uromastyx lizards that are lizard lipped but did not evolve beaks with the advent of ominovry-herbivory. Hell, even the recently discovered fruit eating monitor lizard of the northern Philippines shows no evidence of a beak, and monitor lizard style lips are the style of lip most ascribe to theropods!!

Varanus bitatawa credit ACD CC3.0

Uromastyx acanthinura. credit MAJ Kathleen A. Hoard, U.S. Marine Corpspublic domain http://www.defenseimagery.mil

Don't want to leave out the large bodied herbivorous Jim Morrison lizard king from the Eocene: Barbaturex morrisoni.

When faced with a change in diet lizard lipped lizards never evolve beaks. We have to ask ourselves why did non-avian theropods - presumed by many to have lizard lips - always evolve beaks when faced with a similar change in diet? Convergence is a powerful trend in evolution and to not see any degree in convergence between these two lineages when faced with similar adaptive pressures is an observation not to be dismissed.

It is not like theropods dabbled in growing beaks, they fully embraced beaks. Not just avian theropods but Therizinosauria, Oviraptorsauria, Ornithomimosauria, and Elaphrosaurinae. The reason for this convergence in shared oral anatomy - both the reduction and eventual fully edentulous nature of tooth loss and growth of beaks - is tied intimately with diet and feeding anatomy. However the anatomical feature that precipitated this transition in theropods is lips. The question is what did these lips look like?Not the tight fitting, slightly keratinized and scaled lips as we see in lizards. Lips of this sort don't precipitate beaks as shown by the noted absence of beak evolution in lizards.

If we eliminate lizard lips in theropods - at least from those theropods that evolved beaked forms - we are left with meat curtains and croc lips. However no crcodylomorphs evolved beaks and they messed around with all sorts of diets during their long evolutionary tenure. Now I do think that a number of theropods messed around with keratinized croc like oral margins - but among those that evolved into beaked forms I don't think that such an oral margin occurred.

So by eliminating croc-lips and lizard-lips from the ranks of those theropods that evolved beaks what are we left with? meat curtains.

The style of lips that precipitated the evolution of beaks were of a much more looser and pendulous variety - a far cry from the tight fitting shellac of lizards lips. That theropods equipped with such "meat curtains" unanimously replaced them with keratinized rhamphotheca i.e. "beaks" speaks not to the superiority of this lip design with regards to omnivory-herbivory but to the cumbersome and inefficient design of such lips when engaging in such a diet.

Let's play a little thought experiment: Imagine that you are a putative "lizard lipped" theropod that fits this niche of transitional omnivore-herbivore. As compared to your carnivorous brethren you have to spend a lot more time out and about foraging for food. This diet requires a lot of quick and precise nips and bites. Sometimes you are trying to only eat certain parts of a plant and avoid other parts. Sometimes you are selecting nutritious fruiting bodies or fresh green growth, other times you are precisely picking up fallen fruitifications or seeds off the ground. Since the oral margin you have - your "lips" - is a tight fitting rim of scales there is nothing to really impede this foraging ability. More so than that there is no evolutionary imperative to grow a beak or lose your teeth. In fact your "lizard lips" are already a sort of proto-beak of their own.

Long story short if you were a theropod or a lizard equipped with such an oral anatomy no real evolutionary pressure to tighten and clean up the oral margin - the tight fitting scaled lizard lips do the job just fine. No need to lose your teeth either.

Now contrast this scenario with a putative theropod trending into omnivory-herbivory but instead of giving the animal clean and trim "lizard lips" endow it with the cumbersome and sloppy "meat curtains" lips. Now making all those precise nips, pecks, and bites on small items gets a lot more trickier. Your fully carnivorous brethren have no problem operating with large, drooping lips - a quick and violent bite and snatch is all that is needed. But now you find yourself out and about foraging for a lot longer to get your nutrients. This puts you at risk for predation. Because your lips are big and cumbersome and don't quite form a nice clean cutting edge you find yourself having to bite repeatedly at things. Plucking small seeds and fruits from the ground is sloppy. You can't always make the precise bites on select bits of foliage. All the extra time spent foraging puts you at greater risk from predators.

Faced with such a maladaptive situation the solution is simple: tighten up those fleshy, pendulous lips into a nice trim, neat, and keratinized lippy margin. In other words grow a beak. The exaptation for growing a beak in this scenario is not actually some putative proto-beak or such, no it is the exact opposite, a cumbersome "meat curtain" ill-equipped for precise and repeated bites and pecks. Optimal foraging theory dictates that such an evolutionary change would occur in such animals.

Yes For Limusarus, Herbivory & Beaks, and the Quest for Carotenoids

Now I have been planning to consolidate these ideas for a while now and I knew it was going to be a bit tricky to splice apart how all the different birdy, sort of birdy, weird theropods transitioning into herbivory fit along this gradient from toothy to reduced teeth to edentulous. But then I saw the talk on Limusaurus at SVP 2016 SLC and the subsequent paper came out and it was like a god-send. Limusaurus encapsulated this whole transition from a toothed predator to an edentulous beaked herbivore with gastroliths all nicely wrapped up in one complete ontogenetic package!!



Extreme Ontogenetic Changes in a Ceratosaurian Theropod.

This paper (Wang et. al., 2016) encapsulates in one animal the transition from a carnivorous to a more omnivorous/herbivorous lifestyle. In addition to the growth of a beak and loss of teeth evidence of gastroliths and stable isotopic chemistry provide independent lines of evidence converging on the same conclusion: beaks and the evolution there of are not evolutionary eventualities but are coincident with a transition of carnivorous to herbivorous lifestyles and loss of teeth. This trend is very noticeable in theropods and mention of the seed eating avialian Jeholornis is also warranted as it retains some teeth in immature specimens. Harpymimus too and probably a bunch of others I am forgetting.

Jeholornis credit Matt Martyniuk

As the lippy oral margin gets more keratinized it renders the teeth obsolete furthering the loss of teeth and edentulous condition in omnivorous/herbivorous theropods and ultimately modern birds. That the loss of teeth in theropods transitioning into herbivory is commensurate with a transition into herbivory is bolstered by the retention of teeth in many predatory stem birds/enantiornithines as well as the evolution of "pseudo-teeth" and shredding choannal papillae & serrated tongues in many hunting, fishing, and scavenging birds. Limusaurus and its revelations are so important and, well to put it frankly, startlingly fortuitous in documenting this transition from a predator to a beaked herbivore but in reality there were probably many species that fell upon a gradient of lipped predator to quasi-beaked increasingly keratinized toothed omnivore to fully beaked herbivore. I made some rough illustrations to illustrate this transition:

Stage 1: Fully predatory and fully lipped. Will occasionally augment diet with select fruitifications and stomach contents from herbivore prey for display colors and carotenoids. A diffuse coevolutionary partnership has begun with the propagules of several plants enlisting the aide of such carnivores to help spread seeds (i.e. the rotten flesh/cheese odor of ginkgo fruits). Has undergone evolution of protofeather "dino-fuzz" and has subsequently lost scales on the head and around oral margin. No "lizard lips".



Stage 2. Sexo-social signalling devices have stimulated an increased emphasis on colored display for both skin, osteological, and integumentary display. In turn the increase in dietary plants for carotenoids in the diet to support such color displays has created a shift in foraging patterns. Small animals, insects, and scavenging are still important but hypercarnivory and large game hunting has been supplanted by an increased emphasis on high quality plant material, seeds, fruitifications (i.e. cycad, gingko, podocarp propagules) and other vegetative resources in the quest for carotenoids. Commensurate with this shift into herbivory the loose lips around the oral margin have withdrawn and became more keratinized. Some teeth remain, especially at the jaw dip for both grasping, occasional hunting, and defense but other teeth have been lost. Rictal tissue remains at the juncture of the upper and lower jaws is present and is even important for display. The jaw shortens and becomes deeper.



Stage 3. A fully beaked and fully herbivorous realization. Sexo-social signaling and the quest for carotenoids has finally turned a lipped and predatory theropod into a beaked and herbivorous sexual T. rex. Small animals and occasional scavenging are still opportunistically exploited - especially in growing animals and females - but dedicated herbivory is overwhelmingly important. The pubis has tilted back, gut expanded, gastroliths are present, and adults are completely edentulous.


I think it important to iterate that this is not necessarily a straight line progression and there are lots of room for reversions, deviations, and exceptions to this lipped predator to beaked herbivore transition. How you might choose to slot a particular species in this rough spectrum depends on both the ecology of the animal in question and, as Limusarus suggests, its ontogenetic sequence. For some more thought and reference on beaked, half beaked, beaks and teeth in stem-birds go read Matt Martyniuk's post Theropods That Fit the Bill on DinoGoss.

I think it fair to say that there is no eventuality in evolving beaks; beaks are related to an increased dietary emphasis of herbivory (not flight); and neither the crocodile style oral margin nor the "lizard lips" style oral margin produce beaks as neither herbivorous crocodiles or herbivorous lizards/sauropods produced beaked forms.

The End of Lizard Lipped Theropods? Not So Fast...

Am I suggesting we cast a death knell for lizard lipped theropods? At first I thought yes, but I have recently recast my decision.

What translates a good hypothesis into the realm of theory is that it has predictive power. As I have frequently mentioned in this piece sauropods never grew beaks even though their foraging strategy seems like it should compel them to. Since sauropods are only known to have scales, likely never evolved a full coat of filaments, and therefore never cleared up the scales around and on the face, they likely retained an oral margin not unlike lizards. Sauropods, like lizards never evolved beaks because their oral margin was fine as it was for biting, pecking, and plucking as a herbivore. They also never lost their teeth. Now if we work from that observation and realize that theropods and sauropods are in fact kissing cousins we should presume that at least very close to the base of the theropod and sauropod split - before theropods evolved an integumentary coat and lost the scales on their face - there was in fact a putative lizard lipped theropod. A further prediction for this putative lizard lipped theropod is that if it embarked on a quest for carotenoids for display purposes and transitioned to a more herbivorous diet that it would not actually evolve a beak but instead retain teeth in its jaw. Such an animal would deviate from the trend in all other coelurosaurian "feathered" theropods that evolved beaks and trended into omnivory and herbivory.

Ladies and gentleman such an animal exists and its name is Chilesaurus diegosuarezi.

Chilesaurus credit UNO

Chilesaurus has become somewhat lost in the mire in discussions of herbivory, beaks, and theropods. I will offer it is very important in that it is clearly a theropod that made the transition from carnivore to herbivore but it deviates from the trend of beakyness seen in other more derived theropods that likewise changed dietary ecology. For starters this animal was not new to herbivory, it had a rear pointing pubic bone and expanded gut. Furthermore it occurs exactly where we should expect such early experiments in herbivory to exist mid to late Jurassic suggesting that the earliest transitions to herbivory in theropods may have started in the early Jurassic or even Triassic. Finally, as should be expected for an early off-shoot from lizard lipped theropods this animal did not evolve a beak but retained and expanded large cropping spatulate teeth in the front of the jaw. Just like a lizard - or a sauropod - would.

An enigmatic plant-eating theropod from the Late Jurassic period of Chile

a, Partial right (?) maxilla in lateral view. b, Left premaxilla in medial view. c, Right dentary in lateral view.d, Details of dentary teeth in lingual view. e, Crown of unerupted dentary tooth. f, Detail of the carina of an unerupted…

No beaks on Chilesarus, no sir!!

credit Fernando Novas

Although many of the artistic depictions of Chilesaurus give it proto-beak of sorts I think this is more indicative of convention rather than direct proof of a proto-beak in Chilesaurus.

I would be remiss not to mention Incisivorosaurus guathieri. This animal being a coeulerosaur is on the branch that underwent feathering, so it potentially could have had dispensed with scales on the face and lacked true lizard lips. Yet it follows more of the trend we see in Chilesaurus… interesting. More derived oviraptors lost all of their teeth.

Incisivosaurus gauthieri credit Jaime A. Headden

Did Incisivosaurus actually have a beak? Was it just embarking on the process of keratinizing its oral margin? If it was just in the incipient stages of keratinizing that would explain why teeth are still very apparent and important in its feeding ecology and anatomy. The pubic bone was not quite so retracted in Incisivosaurus as compared to Chilesaurus. So Incisivosaurus differed from Chilesaurus in that it was just in the incipient stages of herbivory while Chilesaurus was much further along in its dedication to herbivory. Go further: The Origin of Oviraptorosaurs (Diet in Oviraptorosaurs III)

As I mentioned on my last post it is hard to ascribe hard and fast rules to these things. As soon as you start to press down and announce "Aha that's it!!" exceptions start to arise. Biology is squishy and messy.

But I do think that this approach looking at the beaked and the beak less with respect to ecological imperatives gives a faint signal of likely facial appearance and 'lippiness" emerging through the murk of deep time.

In short my parting thoughts on the lip question in theropods are; basal theropods near the sauropod split likely had lizard lips; spinosaurids, unenlagines, piscivorous & small game hunters, kinked snouted theropods, and abelisaurids theropods of that gestalt may have had partially or even completely keratinized oral margins or perhaps even split the difference i.e. lips on lower jaw & keratin on above jaw for abelisaurids; derived predatorial theropods that had underwent evolution of "proto-feathers" may have lost scales on the face and therefore lost lizard lips and adopted a quasi-canid looking "meat curtain" lip gestalt; these same "meat curtain" theropods underwent evolution of rhampotheca i.e. "beaks" when sexo-social display structures stimulated increased consumption of carotenoids leading to increased herbivory. Beaked theropods survived the K/T extinction, not coincidentally their survivorship has been attributed to an ability peck and forage for seeds and other small food stuffs with their beaks.

What wears a mask of a beak, hides a former lippy pedigree. No one cares about me until I wear the mask.

credit Danielle Dufault

Works

Larson, D.W.; Brown, C.M.; Evans, D.C. (2016) "Dental disparity and ecological stability in bird-like dinosaurs prior to the end Cretaceous extinction. Current Biology V-26 Issue 10 pp1325-1333. DOI: http://dx.doi.org/10.1016/j.cub.2016.03.039

Theropods That Fit the Bill. Mathew Martyniuk. DinoGoss. January 17, 2011

Novas, F. E.; Salgado, L.; Suárez, M.; Agnolín, F. L.; Ezcurra, M. N. D.; Chimento, N. S. R.; de la Cruz, R.; Isasi, M. P.; Vargas, A. O.; Rubilar-Rogers, D. (2015). "An enigmatic plant-eating theropod from the Late Jurassic period of Chile". Nature. 522: 331–4. doi:10.1038/nature14307.PMID 25915021.

Wang, S.; Stiegler, J.; Amiot, R.; Wang, X.; Du, G.-H.; Clark, J.M.; Xu, X. (2017)."Extreme Ontogenetic Changes in a Ceratosaurian Theropod" (PDF). Cell Biology. 27: 1–5.doi:10.1016/j.cub.2016.10.043.

Plying Abyssal Depths  by Duane Nash

The bull Albertonectes is down deep. Sweeping its massive 7 meter long neck - the longest among elasmosaurs and the most neck vertebrae of any tetrapod - back and forth it lights up bedazzling, psychedielic swarms of bioluminescent organisms of the deep scattering layer. Visible for more than a kilometer this banner of deep sea light plays a purpose for the animal. The elasmosaur is banking on the "deep sea burglar alarm" defense mechanism of the numerous and small denizens of the deep to draw in larger animals for the elasmosaur to ambush. 

The deep sea burglar alarm is a rather clever solution to predation in the dark vastness of the abyssal ocean. This theory rests upon the premise that for any predator of the ocean, there is often something bigger that is a predator of that animal. So if a prey animal is attacked in the dark depths a potential tactic would be to call in a larger predator to take out the animal attacking me. Hence the fabulous light show.

The bull is at home in the cold, crushing depths of the high Arctic Bear Paw Ocean. Despite the exertions from these provocations the massive elasmosaur - over 11 meters long and at 4 tons the weight of an Indian elephant - still has the capacity to remain under for at least 40 minutes. A deep rich blubbery layer and abundant super oxygen saturated blood provide the necessary equipment for such dives. With the ambient light provided by the bioluminescent organisms and pressure sensor receptors along the snout and the length of the neck the bull is well attuned to this environment despite the enveloping darkness. While matrilineal pods of Albertonectes ply the shallower oceans of the coastline these big males do their foraging in the deep, cool and productive water in order to gain weight and stamina over other males when the mating season begins. In those months the males feed rarely at all.

After the bull elasmosaur has litten up an area half the size of a football field it retreats over to the edge of light show, cloaked in darkness, and waits. He does not have to wait long for out of the blackness emerges another topside explorer of these depths. A primitive scromboid fish, itself equipped with advanced thermoregulatory features that allow it to exploit such productive but cold depths, has arrived to investigate the disturbance. At over a meter long the high octane fish - which usually cruises warmer and shallower water during the day in between dives - is usually met with a welcome feast when it investigates such scenes. And here is no exception as it voraciously ram feeds on the various cephalopods, crustaceans, annelids, jellies, and tunicates swarming in the melee. The visual detection of the fish is geared towards near sighted objects, 10 meters below it it does not see or feel the 11 meter long monster of the deep pivoting slowly into strike position. As the fish makes long and straight passes through the light show picking off small organisms the bull Albertonectes recognizes the pattern and anticipates. The fish is faster in the absolute measure of speed but if the elasmosaur can get within 7 meters it has a good chance of snatching it. Noiselessly and effortlessly the massive elasmosaur shifts and hovers into striking distance below the fish. Running along the length of the vertebral column is a channel filled with oils that allow the animal to change its position in the water column like a predatory stealth submarine. When the fish makes a pass hundreds of muscles fire simultaneously along the 7 meter ling neck drawing it upward and lateral to snatch the fish. These muscles, strongest at the base of the neck anchored along the neural spines and transverse processes, move the massive neck with astonishing speed and accuracy against water resistance. The necks purpose sole here to bring a relatively small but toothy mouth into a position to gain purchase. The fish now can sense the movement of a larger animal below it but here the neck of the Albertonectes outperforms the swimming muscles of the fish. A trailing fin of the fish is snagged by two inch long, deeply rooted fangs. As the bulk of the body of the elasmosaur catches up with the course of swimming the neck has set in motion the mouth opens quickly - the gape is amazing for such a small head - to reposition a bite on the gills of the fish. With bulldog like tenacity temporal muscles squeeze tight on the gills of the fish. 

400 meters below the surface of a cool, temperate Cretaceous Artic ocean the life of an ancestor to the tuna dies to support the life of a member of the most resilient and long lasting marine tetrapods ever.

Abyssal Fishing by Duane Nash

The plesiosaur machinations are back!!

As speculative as the above scenario is deep sea burglar alarms are a real thing and considering the ubiquity of bioluminscent organisms in todays oceans such defense tactics likely occurred in Mesozoic oceans as well. Plesiosaurs were probably right there to exploit them as the aquatic bad-asses that they were. Furthermore the take home message - that neck could have been used for all sorts of weird and useful tactics - should not be lost on people.

Because I have said it before and I will say it again: the long neck "plesiosauromorph" bauplan; guild; family - whatever qualifier you want to give it - is the longest tenured and most successful marine tetrapod family of all time. Especially if you go back and consider nothosaurs as part of the radiation plesiosauromorphs beat out macro-pliosuars, ichthyosaurs, sea crocodiles, placodonts, mosasaurs, sea turtles, any and all marine mammal/bird radiations in terms of longevity. Plesiosaurs just kept on sailing along flipping a proverbial middle finger (in the form of a long neck) to all those other marine tetrapod newbies as well as to future hominid interpreters all to eager to characterize plesiosaurs as misshapen, slow, downtrodden, backwards, weak, sucked up, ineffective, cumbersome, ecologically limited and forever the proverbial cannon fodder for the more ferocious, aggressive, and dominant mosasaurs, pliosaurs, ichthyosaurs, sea crocodiles etc. etc.

Changes in  plesiosaur perception are not unlike the revolution sauropods had to go through in the dinosaur renaissance. Early interpretations of sauropods depicted them as bipedally rearing, vigorous land animals. At least in attitude and countenance, if not anatomy, some of the earliest depictions and workers on plesiosaurs got more right than many more contemporary interpretations.






These are quite meme-tastic, no? Lifted from the Pinterest of Denver Fowler.

Far from being lackluster pushovers, these animals were likely highly combative and highly social and most likely combative as a social unit (like certain family oriented skinks) against perceived threats. You did not want big mama Terminonator mad at you because she probably has 5 other cohorts circling beneath and around you ready to take the fight to ya and bite you in all those sensitive areas'!!

These animals were sea monsters but they also may have had a sensitive side. The vastness, coldness, depth, and horrific indifference of the open ocean is an existential threat that every lineage of marine tetrapod has to face. Stare at the abyss long enough and the abyss stares back.



This daunting evolutionary challenge for slowly reproducing, high metabolism, social and air breathing marine tetrapods is most often met not only with tight and intricate social bonds but with reassuring physical contact. Plesiosaurs may have indeed eerily reminded us of sauropterygian equivalents to the highly evolved social marine mammals we are familiar with today.

ALL RIGHT, ALL RIGHT, ALL RIGHT!! Do I got the base riled up enough? Do I got ya' singing the sauropterygian gospel yet??

An incipient pivot has occurred. First and foremost people are really starting to take to this notion of plesiosaur being a lot more thicker... bring the thickness people. Not just thick layers of blubber and skin but absolutely daunting packages of muscles powering both fore and hind flippers - because the 2x penguin (credit Robert Bakker) - is a thing. And not just thick straps of muscle around the torso but thick necks - especially towards the base - are also getting traction.

Mark Witton recently wrote a piece Plesiosaur Paleoart: thoughts for artists in which he echoes a lot of the same sentiments I have been espousing in past plesiosaur machinations with regards to neck thickness, torso muscles, generally a more robust appearance. Make 'em thick.

credit Henry Sharpe used w/permission

And then pictures like this!! What the hell are those elasmosaurids investigating a potential meal larger than a trout breaking with the dogma of "they ate only small fish". Blashemy!!

Credit: © Jorge Blanco

What is this? A throwback of plesiosaurs battling eachother, necks flailing out of the water wildly?!? Restrain your skepticism, it could be that the body is supported from below as the animals are sitting on the seafloor?!?

Mauriciosaurus credit Frey et. al. 2017

A quick little shot out to thick bodied Mauriciosaurus being revealed; further work supporting the aristonectine radiation of filter feeding elasmosaurs; a polycotylid breaking the dogma of "obligate piscivore" and chomping on hesperonithinines.

Don't forget Heavens miraculous thick necked "eel" inspired Alaskan Talkeetna elasmosaur. Awesome work James!! GoFundME.



Yep it does seem like we are in a bit of a renaissance as goes plesiosaurs. And I do detect a faint whiff of plesiosaur machination inspiration in some of these newer interpretations. Long gone are the wimpy, clumsy looking, anachronisms of yore replaced by thick, muscular, confident, and awe inspiring sauropterygian aquatic monster-gods!! Rejoice!!

In light of all these new and wonderful discoveries and depictions of plesiosaurs I want to break with one of my own rules and depict a plesiosaur getting chomped on by another marine predator; not by a mosasaur; not by a pliosaur; not by a shark; but by an ichthyosaur!!

Attenborosaurus vs Macro-predatory Temnodontosaurus credit Duane Nash

I commit such travesty because 1) we don't have many images of macro-predatory ichthyosaurs doing dastardly deeds and 2) Attenborosaurus is one bad ass plesiosaur... urmm pliosaur... what is it?

With regards to point 1) on macro-predatory ichthyosaurs:


We don't often talk enough about macro-predatory ichthyosaurs because though was a big chunk of time in the Triassic to early Jurassic where the marine apex predator throne was held by these guys.  Perhaps due to the early and persistent comparison between dolphins and ichthyosaurs we have somewhat eschewed the monstrous and apex nature of some of these animals. I suspect that they were on the whole more sharklike in swimming motion, that they didn't "porpoise" through the water, and probably a little more opportunistic and "reptilian" in their feeding strategy than dolphins. It is a shame we don't have any living shark toothed dolphins around as they might offer better analogy...

I also did not ascribe a species name to the tempo but just went with a generalized large macro-predatory design. I depicted one of the temnos gulping down an immature Attenborosaurus in a swallowing feat many might be skeptical of.


Consider these points:

Modern animals - both with kinetic and akinetic skulls - swallow down quite sizeable things to a somewhat astonishing degree. We do tend to think of bone as quite rigid and "fixed" structurally but in the living animal it is wet and always has some capacity to deform - probably more so than we might assume from dried and brittle skeletal remains.

Ichthyosaurs, possibly due to their "dolphin" like assumed ecology, have been interpreted to have extremely stiff, unyielding dolphin like skulls or even quasi beaks. But look closely at the lower jaw i.e. mandible of ichthyosaurs - the two halves of the jaw, the dentary bones, do not form a solid connecting structure at the tip of the jaw. Unlike the mandibles of dolphins there is no mandibular symphisis.

T. platyodon no mandibular symphysis

Lyme Regis Ichthyosaur credit BNPS no mandibular symphysis

Could elastic tissue there allowed a certain amount of bowing of the lower jaw there to accommodate large parcels of food? Perhaps augmented by some amount of give along the length of jaw and at the jaw hinge? Even just a little flexure would have assisted swallowing large parcels of food… Additionally how rigid is the mandibular connection to the cranium? Could this have bowed out a bit? I don't know - not an expert - but I think there is enough there to ask: why not? Has adherence to ascribing dolphin like affinities to ichthyosaurs inhibited a more thorough investigation of their ecology and feeding apparatus?

hailing from Char mouth in Dorset U.K. T. platyodon credit Richard Austin

In case you have trouble wrapping your head around macro ichthyosaurs there is the pic above. I saw it on Facebook and thought that it needed wider exposure so I can't claim ownership or even permission to use it but in the spirit of spreading the word about these animals you will not find a better visual representation. T. platyodon may have been more of sperm whale than a killer whale, an idea we will revisit shortly. T. eurycehalus, though smaller, offers a more convincing glimpse at the skull of an apex predator ichthyosaur:

T. eurycephalus. credit Ghedoghedo. CC3.0

In addition to Temnodontosaurus and the various "species" that encompass that genus there was; Thalattoarchon saurophagis revealed a few years back; the mysterious, but potentially gigantic, Himalayasaurus; at the 2016 SVP meeting in Salt Lake City, Utah another massive macro-predatory ichthyosaur was announced hailing from British Columbia.

What is very interesting is that these top dog ichthyosaurs all seem to stem from the Triassic and early Jurassic and then they just peter out and disappear into the Jurassic. And this is a trend that seems to have parallel in many lineages of marine tetrapods that achieve apex predator status. An initial burst of diverse forms and then, over time, they wane off into... very often a niche of specialized deep sea teuthophagy (deep sea squid eaters). This is exactly the case with the formerly dominant and massive raptorial sperms whales as they are now represented solely by a dedicated deep sea squid eater. Could it be that many of the latter pliosaurids were actually specialized deep diving teuthophages? Always assumed to represent traditional pliosaur apex predator roles perhaps species such as  Brachauchensis lucasi; Megacephalosaurus eulerti; Stenorynchosaurus; many of the other quasi polycotylid looking pliosaurs actually had more in common ecologically with sperm whales and pilot whales than killer whales.

Megacephalosaurus marine arch-predator or simply a celebrated squid eater?

Compare the skull of Megacephalosaurus eulerti (FHSM VP 321)- one of the last surviving pliosaurs - to a truly macro-predatorial skull below of Pliosaurus kevanni.

© Jurassic Coast Trust. Sir David Attenborough w/Dorset monster

Blasphemy right? Suggesting that not all pliosauromorphs were marine apex predators ready to go ape shit on any prey in sight… that some may have been more like sperm or pilot whales?

A constant theme of this blog has been unpacking the cultural baggage that comes along with analyzing  extinct animals that are in fact cultural creations. What do I mean when I say that extinct animals that absolutely existed are in fact simultaneously real and cultural creations? The term pliosaur is a loaded terms just as Tyrannosaurus or Smilodon are. When we think of a pliosaur we imagine a huge apex predator that smashed through lesser marine reptiles not necessarily a deep diving specialist on cephalopods… which many later pliosaurs may have been relegated to as sharks and mosasaurs crept into apex predator roles.

Megacephalosaurus eulerti credit MCDinosaurhunter CC3.0

I am not implying that titans like Pliosaurus necessarily evolved into more teuthophagous forms but that over time the apex predators got winnowed away leaving behind deep sea diving squid eating specialists. Life at the top of the photosynthetic marine food web was harsh and any disruption to the system potentially catastrophic for apex predators. However deep sea based food webs - dependent on detritus i.e. "marine snow" and/or chemosynthesis i.e. sulphur consuming organisms, tube worms etc etc. - may offer more stability than shallow water based marine webs dependent on photosynthesis. Which fits the pattern of diverse ichthyosaurs - including macro predator types - getting winnowed away leaving pelagic forms behind; raptorial sperms whales declining in diversity until just a single common teuthophage remains; macro-predatory pliosaurs getting diminished to teuthophagists. Extinct members of the walrus family were once a lot more diverse and some may have been highly predatory - now we are left with an arctic specialist of shelled mollusks. Shark toothed dolphins may have been much more broad in their ecology than most modern dolphins. I would not be surprised if a more predatory extinct penguin comes to see the light of day, if it has not already and we simply have overlooked it…

By the way I thought I would give some exposure to a rather excellent and thoroughly interesting Royal Tyrell Musuem video on the underreported swell of large apex sharks in Cretaceous with some interesting musings on which sharks might emerge as apex marine predators of future oceans.



What should become clear from the above video is how - when an oceanic apex predator declines - another group is waiting in the wings to fill that vacated niche. Nature abhors a vacuum.

So to summarize my thoughts on the matter and to paint with a very broad stroke I detect some common trends in several marine tetrapod adaptive radiations and extinctions:

1) Following large extinction event marine tetrapod clade diversifies rapidly including apex predator and deep sea diving forms.

2) Repeated environmental catastrophes usher in extinction events especially at the apex predator role. Deep sea teuthophage specialists remain relatively steady.

3) Invasions from other marine tetrapods into vacated marine eco-space inhibit reoccupation of niche space further winnowing away diversity. The last holdouts of formerly diverse radiations occupy offshore, deep diving, teuthophagist niches.

4) Large enough perturbations eventually kill off even offshore deep diving specialists rendering a full scale extinction of clade (i.e. ichthyosaurs, marine crocodiles, pliosauromorphs). Animals become so rare that loss of genetic diversity makes extinction a statistical eventuality.

Which brings us right back to the long necked plesiosaurs i.e. the "plesiosauromorph" bauplan. It just kept sailing along. While all of the other marine reptile clades fell away the plesiosauromorph dynasty just kept chugging along, a remarkably consistent pedigree of success.

We have to ask why?

I want to give that question room to breath a bit, I will come back to it in a future post. My current thinking is that plesiosauromorphs were exceptionally opportunistic not just in feeding but in habitat choice. The wide feeding envelop including everything from benthic organisms (clams, worms, crustaceans etc etc), mesopelagic fish/cephalopods, small/weak marine tetrapods, and scavenging combined with an exploitation of marine ecosystems ranging from deep abyssal offshore pelagic (as supported by histological evidence of "the bends") to estuarine/large river complexes offered strong resilience to environmental catastrophes.

And now finally on to point #2) Attenborousaurus is one bad plesiosaur or… pliosaur… what the hell is it anyways?

First things first how cool is it that this animal is named after Sir Richard Attenborough by none other than Dr. Robert Bakker. Back to the gist of the matter is Attenborousaurus a pliosaur or a plesiosaur? Well let us give it the 5th grade test. The 5th grade test is: "does this animal look like the Loch Ness monster?". The answer is unequivocally YES!! Phylogentically this animal is on the path towards latter true macro-pliosaurs that do fit our popular image of what a classic pliosaur does but - sheesh look at the neck - it probably has more in common ecologically and behaviorally with true long necked "plesiosauromorphs". A shape shifter caught in the act of shape shifting.

Attenborousaurus credit Adam Smith. plesiosaur directory

Yes, it is true that relative to other plesiosauromorphs this animal has a largish head. But in absolute size the head of this animal is not larger than many of the latter elasmosaurids and probably both were capable of the same predatory feats. In essence those that are ok with ascribing mesopredator tendencies to Attenborosaurus should ascribe the same tendencies to other plesiosauromorphs with similar sized jaws. An 18 inch skull with 2 inch teeth is just as effective on a 15 foot animal as it is on a 30 foot animal.

Attenborousaurus credit Adam Smith plesiosaur directory

What we see in Attenborousaurus is a trend towards the apex predator realm, essentially falling short due to the arch predator ichthyosaurs which still occurred in the Sinemarian. The shape shifting plesiosaurs would not be held back and that trend would continue into Rhomaleousaurus a truly impressive animal and perhaps our first best evidence of plesiosaurs making headway into apex predator territory.

credit Adam Smith. plesiosaur directory Rhomaleosaurus cramptoni w/curator Matt Williams. Bath Royal Literary & Scientific Institute

Something appears to have opened up the doors for sauropterygians to truly reach this potential. Let us look at a little time line here. Rhomaleosaurus dates to the Toarcian of the early Jurassic. Temnodontosaurus - the complex genus potentially representing the last of the macro-predatory ichthyosaurs - dates from the Hattengian to the Toarcian. Atennborosaurus occurs smack dab in the middle of apex predator ichthyosaur dominion, explaining why it did not become a truly pliosaur looking pliosaur. Could the waning macro-ichthyosaurs - perhaps already trending into deep diving offshore cephalopod specialists with some species of Temnodontosaurs - have allowed the proliferation of true macro-predatory pliosaurs? The suggestion is certainly there…

Or that is what I thought. Further investigation revealed that the daunting panappoly of late Triassic/Early Jurassic plesiosaurs revealed one early macro predatory pliosaur from the Hettangian age of the earliest Jurassic - what has formerly been referred to as "Rhomaleosaurus" megacephalus but which Adam Smith has cleaned up taxonomically as Atychodracon megacephalus. Things always tend to get more complicated the more that you peer into them. I still think that there was an interesting give and take between macro-predatory ichthyosaurs and the first macro-predatory pliosauromorphs. Perhaps the transition was already underway in the late Triassic?

Way back in the Triassic ichthyosaurs and nothosaurs were seemingly in a dead heat for that position as both scary huge Nothosaurus giganteus & N. zhangioccurred and coincided with macro-predaotry ichthyosaurs Thalattoarchon& Cymbospondylus. The ichthyosaurs appear to have won out, I don't know of any macro-predatory nothosaurs making it into the Jurassic. However sauropoterygian relatives of this vanquished class would eventually muscle in over the ichthyosaurs at the apex predator realm.

mandibular symphysis Nothosaurus zhangi credit Liu et al. 2014

Well I'm gonna leave it off right there. Probably a lot to think about; marine arch-predator musical chairs; shape shifting plesiosaurs; the consistent plesiosauromorph bauplan. I hope you enjoyed this and I hope you start to look at plesiosaurs with a new eye. I want to do one more post in the series, end it at lucky number 13 of course, and for this one I want to break one of my own rules: let me know if there are any topics or species I should cover for my last and final installment in the plesiosaur machinations and I will try to work them in. So I am taking requests in the comments.

best,

Duane



Some might be new to the plesiosaur machinations - allow me to indoctrinate. Or, if you have perused the evil machinations before, here is a quick summary and chance to review.

Yes Another Hypothesis on Long Necked Plesiosaur Feeding Ecology: In which I lay out rotational feeding i.e. twist feeding as a method to de-shell large ammonites. A little dated but possible...

Thus Spoke Zarafasaura In this post I lay the foundation for what eventually becomes the plesiosaur machinations by focusing on a particularly brutal looking elasmosaurs Zarafasaura; review plesiosaur art; death by quartering.

Plesiosaur Machinations I: Introducing the Plesiosaur Phalanx Attack

In the introductory post I discuss how a group foraging strategy would facilitate successful and efficient foraging for plesiosauromorphs; make the comparison between white pelicans and grey reef sharks; discussion on a wider prey envelope than generally appreciated; the shark genus Somniosus as a model for cryptic stealth technique.

Plesiosaur Machinations II: The Social Sauropterygian

In this post I advocate the familial unit as the basis for understanding plesiosaur ecology and behavior. I advocate several social lizards - especially skinks - as model organisms for how reptilian aptitude animals can establish social unity and cohesion. Anti-predator behavior is advocated to be antagonist and mobbing cooperative advancements against potential threats.

Plesiosaur Machinations III: The Family That Slays Together, Stays Together

Embellishing the social unity concept and exploring how simple biochemical feedback loops could have enhanced social unity merely through proximate physical contact. The long neck is proposed as an effective tactile appendage for physical contact.

Plesiosaur Machinations IV: He is the Last You'll Know…

Discussion on the feasibility of scavenging in plesiosaurs; plesiosaurs exploiting anoxic die off events; Meyerasaurus and Temnodontosaurus; Meyerasaurus proposed as analogous to oceanic white tip sharks.

Plesiosaur Machinations V: Despot Ammonite Slayer

Plesiosaurs feasting on ammonites, marine escargot…

Plesiosaur Machinations VI: WE BITE!!

Plesiosaurs and the misfits. Why you don't want to get bit by a plesiosaur. How many plesiosaurs fall outside the "obligate piscivore" morphology. Occitanosaurus being naughty. Mesopredator plesiosaurs.

Plesiosaur Machinations VII: You Can't Handle the Thickness

No more Jack Skeleton plesiosaurs. Make them thick and don't apologize for it. Stout muscular necks, thick torsos, plump tails, bulging "knot head" temporal muscles, and juicy blubbery layers. A machination classic.

Plesiosaur Machinations VIII: The Strange Case of Cope's Mosasaur Inside and Elasmosaur

We may never know the answer but I would not be so quick to dismiss… Another classic yet controversial machination.

Plesiosaur Machinations IX: In the Belly of the Beast

The varied and strange things found inside plesiosaur torsos. Includes my take on how a voided ichthyosaur embryo actually ended up in the stomach of a plesiosaur. 

Plesiosaur Machinations X: Senior Water Rights

Sauropods and plesiosaurs. Mosasaurs and elasmosaur arms race. Elasmosaurs prefer cooler waters. California elasmosaurs. Elasmosaurus vs. Tylosaurus revisited.

Plesiosaur Machinations XI: Imitation Crab Meat Conveyor Belt and Filter Feeding Plesiosaurs

The neck as a food storage device and aristonectine giant filter feeding elasmosaurids!!

Gaslight: Manipulate (someone) into questioning their own sanity by psychological means.

I've been wanting to write this post for a while but it was the revelation of two recent significant works that have crested into the perfect wave substantiating some undercurrent of sentiment I've been trying to crystalize in my brain cells.

Dinosaurs  might be getting a lot more unstable, contentious, and freakishly weird and unpredictable   before any type of normalcy and "consensus" view gains traction. Can you feel the instability under your feet?Are we in a post-fact dinosaur era?  What I have referred to as the dinosaur "weirdening" might also be understood as sort of a post-modern enlightening of dinosaur studies or even paleontology as a whole. For those that like to see things in black and white it might not be an especially pleasant road ahead for you. However for those that are willing to admit and forego their own biases; become comfortable with not knowing or better yet unknowing things; and have the audacity and humility to push forward regardless of nit-pickers, naysayers, and general haters these are indeed golden times in dinosaur studies.

What do I mean when I say we should have humility and audacity? Are not those two traits somewhat contradicting?

We should have humility in recognizing that the errors, oversights, and dogma in modern dinosaur paleontology occur just the same way that they did before the dinosaur renaissance. We might not be making the same errors, just a whole different batch of errors. What do I mean by this? Has not dinosaurs paleontology become a much more concrete science in the last couple of decades? Have we not dispensed with the ol' storytellers and "just so" charlatans of yesteryear? Paleontologists don't tell stories anymore - they measure stuff, compile data, and matrix things. Science the shit out of dinosaurs. Paleontology, and especially dinosaur paleontology, has evolved radically - one need only visit and talk to the presenters at the annual SVP conference to see the rigor and abstinence of speculating beyond the data, from telling stories.

The more evocative, dynamic Robert Bakker school of dinosaur paleontology has been supplanted by the more measured, rigorous "testable" prototype - what I refer to as the Lawrence Witmore protege  that dominates modern dinosaur paleontology. In fact I would trace this transition to a cover story in National Geographic magazine from March 2003 that documented the hardening of the arteries in dinosaur paleontology. Dinosaur science was no longer the place for story telling and whimsical notions.

"This is a good thing though. We need paleontology, and especially dinosaurs paleontology, to be a rigorous science. Good riddance to the Bakkerian notions that have plagued dinosaur paleontology"

Yes, but in eschewing the more story telling, fantastical, out there, "speculative" branch of dinosaur paleontology dinosaur science has lost it's soul. The arteries of paleontology have hardened and a plaque has formed limiting the flow of the true life's blood of dinosaur paleontology - imagination.

"Imagination is more important than knowledge. For knowledge is limited to all we know and understand, while imagination embraces the entire world, and all there ever will be to know and understand." - Albert Einstein

In the dispensing of story telling in dinosaur paleontology the science has lost something that it desperately needs to regain - something that the "All Yesterdays" movement addressed but must go even further with. All Yesterdays asked "what is the role of speculation in paleontology", however it was an open ended question and no concrete answer was given. The answer is two-fold I will suggest; imagination, new ideas, and concepts till the ground for new hypotheses, theories, and paradigms to emerge and; paleontology has changed - but people have not. As I said earlier many (not all) of the crop of top thinkers, paleontologists - teh luminaries if you will - are doomed to follow in the footsteps of the people that the dinosaur renaissance made look so foolish - not because they are foolish or stupid - they most certainly are not just as the people who were made obsolete by the dinosaur renaissance were not actually stupid. But there will be casualties along the way because people have not changed - even as the science has - because people are and always have been full of shit to various degrees. I'm full of shit, so are you reading this full of shit - we are full of shit because we have egos, biases, and groupthink is a thing that social primates do for good reasons until the bag of shit becomes soooo stinky someone has to ask what is that smell? What is that smell in dinosaur paleontology?

The Loss of the Narrative in Modern Dinosaur Paleontology and Why We Are Worse Off For It

Dinosaurs paleontology has largely forgot how to tell stories. How to narrate, how to blend science, art, and imagination into something truly uplifting, captivating, and mystical. The ability to take the mind and stop it. Not stop the mind in the sense of stop thinking - but simply hit it so hard you get a little stunned.

Ask yourself what got you into dinosaurs - was it a character matrix - or was it an evocative scene, picture, or vignette that hooked you? Paleontologists need to embrace storytelling and narratives once again. One doesn't need ignore or eschew the foundational science while also embracing the more mythical narrative ethos of paleontology.

As paleontology - especially dinosaur paleontology has shifted from the narrative - from "what might be" to "what we know for sure" it has left a void. Who tells the stories? If paleontologists don't create the stories that people hear about dinosaurs guess who does? The screenwriters of Jurassic World get to create the stories that people hear about dinosaurs that's who. And paleontologists have no one to blame for that but themselves for this predicament. Because say what you will about Bakkerian ideas - he sold them well enough - and those ideas, somewhat dated, still inform the Jurassic Park franchise to this day because of his craftsmanship.

I speak with the audacity that I do because I guarantee that my arch scavenger/hunter vulturine dromies would mop the floor with both those JP reptoid freaks & dapper ground hawks and absolutely traumatize audiences ; that a slow, creeping, silent assassin, super-senses endowed, night staking T. rex would send more shivers down the spine of movie goers than anything Hollywood or modern paleontology has came up with; that a bottom punting, water hunting Spinosaurus is the coolest damn thing you could have laid eyes on in the Cenomanian or in the local movie theatre; Allosaurs massing on a sauropod carcass, necks pistoning back and forth, rendering muscle, sinew, and bone, like some macabre gaggle of vultures on steroids. My dinosaurs would kick Spielberg's, Bakker's, Paul's, and Horner's dinosaurs asses combined. Fact. No freaking contest.

I mentioned earlier we should have the audacity to posit what dinosaurs were like. Now I might be wrong in some of my interpretations above, time may tell. But I have the audacity to posit such non-standard interpretations and defend them and create the wiggle room from which further studies may confirm or deny such ideas. More so than that a piece of evidence in favor of non-standard ideas might be overlooked without a framework for understanding new data in a different context. Saying nothing would be the greater wrong-doing than saying something that is later disproven.

Sauropods and Theropods Kissing Cousins No More….

Diplos for Allo Brunch by Duane Nash

Theropods and sauropods (evolutionary) friends to the end, or, maybe not? Sauropods decoupled from theropods while ornithischians and theropods linked into Ornithoscelida (Baron et. al. 2017). A good summary.

This work really is a game changer. For me the most interesting aspect of this - if it pans out and I have seen or heard of no strong counters to it as of yet - is the alarming amount of time the faulty saurischian/ornithischian split went on basically unquestioned.

I mean really guys? 

Now I buy a lot of technical dinosaur books. In these books I usually have to sift through like a ton of cladistic stuff before I can get to the snippet of mention of stuff  I am into like soft tissue, diet, behavior, ecology. The message I get is that phylogeny & cladistics is the "harder" aspect of dinosaur science and therefore gets more attention and pages. While diet, ecology, behavior, soft tissue falls under a more subjective and less rigorous banner presumably. Except now that I learn that the foundational dividing line separating ornithischians and saurischians might be hogwash, simply unquestioned dogma. Do you see where I am coming from? Teacher teaches without question student accepts blindly repeat ad nauseum…

That so many researchers focus on phylogeny and for this foundational aspect of the dinosaur family tree to go on seemingly unchallenged for so long, it does beg the question… are new thinkers being challenging enough? You need to be absolutely challenging and even somewhat combative against what your teacher is teaching you. And these same teachers need to love you for it.

Kaiju Dinosaur

Interestingly enough it is the revitalization of the kaiju film that offers more inspiration and hope for stoking the flames of dinosaur inspiration/lore than the dinosaur theme park movies at this point. Ironic that an explicitly fictional movie genre - kaiju films, literally meaning "strange beast" - is arguably offering more insight into dinosaurs than a film saga explicitly starring purportedly actual dinosaurs. Duane what the hell are you talking about?!?

Let us break down some commonalities between kaiju and macro-dinosaurs.

Kaiju lived for millennia and grew through multiple ontogenetic sequences. Dinosaurs lived for decades and occupied multiple ontogenetic ecological spaces. Jurassic franchise does not touch upon this concept. In fact in the Jurassic franchise fully grown dinosaurs seem to just inexplicably appear over night.

Kaiju can be seen as hoarders and harvesters of great mineral and energy wealth, they literally transform their ecosystem and form it to their will. Macro-dinosaurs likewise harvested caloric and mineral wealth from their ecosystem at vast scales in the process transforming the landscape. The Jurassic franchise does not touch upon this aspect.

Kaiju have two main reproductive strategies. Some, such as the Cloverfield monster, literally shed off replicating chunks of DNA in large batches. This closely matches the lay 'em and leave 'em strategy of sauropods. However most Kaiju have especially slow and low reproductive potential - seemingly at odds with how dinosaurs are now traditionally thought of as fecund r-strategists.


Or were dinosaurs such R-strategy specialists?

Indeed it is a stance that we need to constantly test and challenge. A recent paper illuminating the tremendous incubation time for the eggs of several dinosaur species  directly calls into question dinosaur fecundity and reproductive strategy(Erickson, 2016). Now this paper measured the incubation period of just two dinosaur species - Protoceratopos andrewsi & Hypacrosaurus stebegeri - which were revealed through careful analysis of incremental growth lines of embryonic teeth to have incubation periods of from 3 to 6 months!!   From this the authors speculated that such long incubation inhibited repopulation after cataclysmic events and that the bird off-branch of theropods (pennaraptora maybe?) was potentially unique in evolving relatively short incubation periods. That is their take home speculation, we will see how it pans out over time and if other dinosaurs indeed had such long incubation periods. Keep in mind if the unification of theropods and ornithischians solidifies then theropods having crocodile length incubatory periods may become a very tenable position.

My take home speculation is something else entirely, that if such long incubation periods were the norm for most dinosaurs - we will see - that potentially this shuffles the cards in favor of:

More intense pair bonding between male and female dinosaurs. It seems unreasonable that high metabolic females would do all of the nest guarding as modern female crocodiles do. After all 3-6 months is a long time to watch over eggs and taking turns over clutch guarding duties seems like a better solution. This also opens up a pandoras box of question in terms of mating fidelity, long term bonding, social cohesion, and perhaps given the stresses of a 3-6 month wait period perhaps females - or mated couples - only reproduced every other year, like some albatross species?!?

The nest as the foci for social, ecologic, and reproductive space. Keeping animals around a nesting space for 3 to 6 months is going to impose some pretty harsh consequences on the local landscape. Big dinosaurs could not fly or swim away to feed as nesting sea birds and marine mammal rookeries do. They were somewhat limited in how far they could travel and would experience diminishing returns as the immediate environment got depleted and longer foraging trips became cost prohibitive. Did they fast? Did mates bring back or regurgitate food stuffs for their partners? Some interesting questions there…

It is worth reminding ourselves that dinosaurs - if they did have crocodile length incubation periods - were not crocodiles. They were not slow metabolism, aquatic ambush predators that could simply lounge around and guard a clutch of eggs for 6 months eating very little or nothing. They also did not live for the 60 to 100 years like crocodiles, but had a much more restricted reproductive window. The clutches for dinosaurs were on the whole smaller than the clutch size of crocodiles. In short dinosaurs potentially had the long incubation span of crocodiles, further burdened with a smaller clutch size, shorter reproductive life span, higher metabolism and food/territory considerations, and exposure to predators/competitors/detrimental environment that caring for a nest for 3-6 months would entail.

Much of the reaction to the long incubation period has been skepticism or negating it on the premise that it covers only two species. Remember two species with long incubation periods is two more species than we have evidence for that exhibit short, avian length incubation periods... As I have already discussed with the dinosaur phylogeny situation, people are complacent with what they know or what they think they know. And what people have been shifting towards in the last couple of decades is that dinosaur nesting & reproduction was largely a lay 'em and leave 'em state of affairs with post hatchling parental care and investment limited at best. Sometimes even antagonistic especially with theropods. But this thinking might be due for a reboot.


How can you forget the M.U.T.O. (s) from the  2014 Godzilla reboot - the true stars of the movie? And it is in their reproductive ecology narrative that we can get some inspiration for dinosaur reproduction. A long trajectory into adulthood akin to the ontogenetic evolution of dinosaurs. Sequestering of tremendous resources - radiation for the MUTO - parallels the conquest for caloric and mineral resources dinosaurs sought. An epic, prolonged, and ritualized courtship. MUTOS had to call via echolocation for each other across continents - dinosaurs had to locate one another across long distances via low frequency calls. The choice of nesting grounds was not without its own burdens. MUTOS needed  their progeny to have a ready supply of radiation to feast upon. And dinosaurs needed to nest at a location that offered abundant resources for their own young. Even when a suitable partner was met, nesting site was located, abundant food in the vicinity, and eggs deposited things could go wrong. Godzilla could show up. Remember the heart-breaking emotive cries of the big momma MUTO when her clutch was destroyed? Epic battles ensued for both kaiju and dinosaurs because the reproductive stakes are that high.

In short I think that this work on egg length incubation is potentially as groundbreaking as the dinosaur taxonomy shake-up. Strangely, and I can only speculate on this, the egg length incubation paper did not receive nary the coverage or amazement as the ornithoscelida paper. Maybe we lack the framework for understanding just how much long incubation implies for dinosaur reproductive ecology. Personally I think it reshuffles the deck on many of the foundational conceits we make on many aspects of dinosaur behavior we take a little for granted. It really is that important in my opinion.

I also think that the small window of reproductive years, long incubation period, and intense competition for territory, mineral, and caloric resources at nesting locations compels us to look more and more at the possible prevalence of vocal, behavioral, and visual display structures in dinosaurs. Moods, intentions, and capabilities had to be conveyed clearly and explicitly at distance or in proximity. We already know of lots of evidence of display structures via skeletal structures but the scope and ubiquity of soft tissue structures across all dinosaurs is likely higher than generally assumed. Especially those soft tissues that can be inflated, engorged, and/or changed in color. Again, I and some others have long argued this, but the incubation work and its potential implications really crystalizes the high stakes nature of dinosaur social and reproductive ecology. It was a wild and wooly world - finite reproductive windows combined with finite resources created an anarchy of display forms and behaviors that we are just scratching the surface at.

The hedging in towards the safe and conservative becomes counterproductive if what you are studying - dinosaurs - are not actually safe and conservative. I think we are getting to that tipping point in dinosaur paleontology, where the outlandish and speculative is becoming more and more tenable, because we are in fact finally starting to concede that dinosaurs by their very nature were outlandish and not conservative.

Revelations by Duane Nash

Works

Baron MG, Norman DB, Barret PM (2017) A new hypothesis of dinosaur relationships and early dinosaur evolution. Nature March 23, 2017

Erickson GM, Zelenitsky DK, Kay DI, Norell MA (2016) Dinosaur incubation periods directly determined from growth-line counts in embryonic teeth show reptilian grade development. Proceeding National Academy of Sciences vol. 114 no. 3 December 1, 2016

"A Long habit of not thinking a thing wrong, gives it a superficial appearance of being right, and raises at first a formidable outcry in defense of custom". Thomas Paine

We all know what this post is about.

Below I will present a few small screen grabs cut out of larger pics of skulls. Let's just say that the representative animals are quite diverse phylogenetically. But despite the disparate vertebrae groups there are some striking similarities - and differences - in the bony texture. Before I reveal what animals are represented I would like readers to simply focus on the textures and patterns at hand, without any phylogenetic prejudices in mind.

One of these things is not like the other…

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J.



K.





Again, without any phylogenetic prejudices creeping into your decision making, what similarities and differences do you observe? Which examples are more textured, which are less? There is a story to tell in all of this I will suggest and after the players are revealed I am going to offer that it is more behavioral - more adaptationist (there is that dirty word again) - than strictly phylogenetic.
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A. Belongs to a stinkin' fur ball, the lowland Paca. Amazing is it not? These zygmotatic plates have something to do with the sound propagation of this cheeky little guy. Not only is this animal a bit of an outlier for its mammalian pedigree but it is also an outlier for its terrestrial inclinations.

Lowland Paca. Cuniculus Paca credit Paolo W. Viscari Specimen of the Week

B. One of several fishes I will be highlighting. This is the fanged blenny - Meicanthus grammisteus - which injects an opioid peptide into its prey to sedate them. Incidentally I came across a link to this fish on Facebook on the same day as the Carr paper was dominating my fb news feeds. Credit Brian Fry.


C. Some gnarly looking catfish I "borrowed" off of Flickr. Thanks credit and © to Lonmelo.


D. Another fish, the North American bowfin. Coincidentally another predatory ambush predator of murky aquatic haunts… are you sensing a pattern yet?

North American Bowfin credit

E. American Crocodile. Exceptionally large and rugose skull.

American Crocodile. Credit Daderot Public Domain

F. Another aquatic tactile predator - Suchomimus tenerensis !! credit James St. John.


G. Another nippy creature of murky habits: Amphiuma tridactylum found on Tet Zoo originally from flickr site Boneman 81.


H. Ho hum, another swamp monster Metoposaurus credit Jeyradan, public domain.


I. Daspletosaurus horneri. Does it really compare that favorably to the other examples? I'm not seeing it. There is a general rugose nature to it, but hardly as intricate bone texture as the other examples…


J. The alligator snapping turtle. Seriously what is up with highly textured facial bone among stealth aquatic predators? Credit, pic allows zoom in functions.


K. Yet another textured skulled aquatic predator, the phytosaur Pseudopalatus mccauleyi. Petrified National Park credit Park Ranger. uploaded FunkMonk



Did I hit you over the head enough with rugose skulled swamp monsters?

The recent paper on the Two Medicine Formation tyrannosaur and associated facial integument inferences (Carr et al., 2017) makes the case that crocodile facial integument is the best inference for tyrannosaur facial integument. Also worth mentioning is that this is the argument that Tracy L. Ford (Ford, 2015) has long been making for quite some time (though Carr et al. did not deem fit to mention him). While the media has certainly ran with the story, at least in the online paleo community reaction to this inference has been highly skeptical. I don't want to recount the variable criticisms to Carr et al's inferences as many have done that already. However what  should not be lost on our observations is that several of these textured skulls above come from animals that do not have tightly adhering skin texture such as the various amphibians. Or even have scales at all.

There is potentially a story to tell here...

Let me make another analogy to fantasy creatures. For me one of the most entertaining aspects of fantasy creature creation is to unpack the various - and often times disparate - elements from contemporary or extinct creatures that are spliced together to create a fictional animal. For me one of the most successful creature splices of recent years is the Bashee and Great leonopteryx from Avatar. Darren Naish does an excellent unpacking of the various inspirations and spliced bits of microraptor, bird, pterosaur, bat, fish, and sports car design that went into the creation of these animals.


It is the liberty in splicing all of these disparate animals together that creature creators do to make a strange but believable fictional animal  that paleontology needs to take more inspiration from.

I think the Carr paper is valuable because it draws attention to crocodile skull texture. Yes it is true that tyrannosaurid skulls show some gross similarity to crocodile skulls in sharing a rugose texture and if you had to draw a rough comparison as to what animal best matches large tyrannosaur skull texture crocs are a good analogy. But crocs evince this rugosity all over the skull, tyrannosaurids have many smooth parts with the rugose sections being localized across more of the rostral sections. Of the animals presented above I would posit the Daspletosaurus skull as being the most different texturally from the others. People are naturally drawn to to comparing tyrannosaurids to crocodiles because they are related and predatory. However most theropods (except spinosaurids) are quite distinct from crocodiles ecologically. And that is the gist of what I am suggesting, we are potentially witnessing bone texture as an ecological signal - not as a phylogenetic/anatomical one. Instead of asking; what other archosaur skull looks most like a tyrannosaur skull? we should be asking; why does a crocodile skull look so similar texturally to a temnospondyl, catfish, snapping turle etc etc. skull? 

When we see a diverse array of animals exhibit a remarkable similarity in facial bone texture as well as a remarkable congruence of ecological niche - ambush predator of murky, aquatic haunts - we have to seriously question if this bone texture is really a phylogenetic-anatomical message or an ecological one. There is more than a reasonable and persistent trend of highly pitted, rugose, and textured skulls among aquatic and amphibious stealth/ambush predators. The question is why?

My hypothesis is that such skulls in aquatic predators - highly textured with increased surface area but still maintaining streamlining - work as enhanced sound/vibrational interceptors. Like an old, well used catching mit these rugose skulls are better able to intercept, transmit, and "grab" acoustical/vibrational frequencies in a visually limiting aquatic environment. Vibration may travel through tissues in different ways and bone might offer an added layer of frequency interception that - when combined with other tactile organs  (nerve endings, pressure domes, "whiskers" etc. etc. ) allows for a more comprehensive reading of the environment.

So why do tyrannosaurs - and many theropods - have such rugose skulls? Well in the case of spinosaurids (and maybe other theropods that exploited aquatic environments predominantly) it is possible they converged on a highly textured design for the same reason that other aquatic predators potentially did - it enhanced sensitivity. For most other other theropod skulls - including tyrannosaurids -  I would like to advance an argument from material science: that there is a relationship between bonding strength and surface roughness. In this case the two materials are skin and bone and a rugose bone texture allows for skin to better anchor on the skull - growing into all of the nooks and crannies with increased surface area - in light of a particularly traumatic bite prone existence. That this bone texture is most prominent on the parts of the "snout" most devoid of overlaying musculature and exposed to bites we should expect this rugose nature to be most prominent there. Which it is. Unlike a crocodile skull which displays rugose formations across almost all of the skull - in line with the potential use of such rugose formations to discern water borne vibrations.

Crocodylusporosus credit

There is potential analogy to the textured skull of theropods acting as a structural adhesive to skin argument: hippo skulls. Animals which have tremendous lips and a very battle prone, bite weary existence. They don't have smooth bone where the lips and skin anchor - they have textured, rugose bone .

credit stock vault author Bjorgvin Gudmundsson

And for the record I do agree with Carr et al. (and Tracy L. Ford btw) that tyrannosaurids (& other theropods) did have exquisitely sensitive, tactile faces. But it was through large lips that grew out from the neurovascular foramina that these nerve endings felt and sensed their world - both the real time struggles of their prey and the touch of a mate or hatchling. It is patently obvious that the pattern of foramina on the dentary (bottom jaw) are arranged in such a way that the upper teeth will not cut into the labial tissue that grows out from them. Note that this is not the pattern we see the foramina take in the crocodile dentary - where they emerge right up next to the teeth.

I also agree that they were probably more romantic and tender than we might typically imagine.

Sources

Ford, T. L., 2015, Tactile faced Theropods: Journal of 
Vertebrate Paleontology, SVP 75th annual meeting, Meeting Program & Abstracts, 
p. 125.


"A Long habit of not thinking a thing wrong, gives it a superficial appearance of being right, and raises at first a formidable outcry in defense of custom". Thomas Paine

River Bottom Running Ankylosaurus created for this blog piece by Robin Liesens

Dinosaurs back in the water and it feels sooo good… There are probably fewer narratives, memes, and dialogues as storied as the on and off again love affair between dinosaurs and the water in both scientific and popular forums. From pre-renaissance snorkeling duckbills and bottom walking brontosaurs to fanciful water world assertions that all dinosaurs were aquatic to bona-fide actual aquatic dinosaurs such as Spinosaurus the concept of dinosaurs in the water is one that is not soon to leave us. Dinosaurs sloshing, mucking, wallowing, foraging, and hiding in the water is an evocative suggestion because such depictions are not without analogue in many modern terrestrial tetrapods and large mammals in particular.

It is a contention of mine and this piece that just because an animal is not explicitly aquatic does not negate the potential for water to still shape and inform significant aspects of its biology and anatomy.

credit Burian

The opening depiction of a bottom running Ankylosaurus, kindly provided by Robin Liesens (Dontknowwhattodraw94), represents what I view as a logical culmination of the ornithischian body plan with relation to water. Ankylosaurus was quite possibly a sinker not a floater. An evolutionary arms race in ornithischians that gave this branch of dinosaurs especially thick, dense skin to protect from both theropods and intraspecific combat; an osteoderm studded skin; lack of skeletal pneumaticity; thick bones.  What this creates is the distinct possibility that ankylosaurids and perhaps other "dense" ornithischians - especially among thyreophorans and marginocephalians - did not actually float in the water as humans, birds, and most terrestrial mammals do but would sink right to the bottom like hippos, tapirs, and water chevrotains.

Bottom punting animals have a rich history here at antediluvian salad: bottom punting Spinosaurus is the ultimate conclusion I reached regarding the most likely aquatic propulsion for that animal. A necessary caveat of a good bottom punter that utilizes body density (as opposed to changing/shifting lung volume like aquatic turtles & crocodiles) is that actual swimming ability decreases as punting ability - and therefore body density - increases. This creates the paradoxical situation in hippos where they can not actually swim - hippos can not cross deep bodies of water because they sink like a stone. The same situation may have occurred in several ornithischians with thick dermis - not necessarily because they were semi-aquatic like hippos - but because they had embarked on a social and defensive strategy of thick skin, armor, and dense non-pneumatic skeletons. Body density and therefore punting ability and the inferred possible loss of actual swimming ability is an interesting side effect of their particular defensive anatomical pedigree.

All of this discussion should be couched in the recent elucidation (not withstanding a rebuttal) of a revelatory linkage of theropods and ornithischians into ornithoscelida (Baron, 2017). One of the most interesting questions that this linkage of neo-theropods and ornithischians raises is "why would ornithischians have lost the highly pneumatic (and presumably air sac filled) skeletons that most likely was ancestral to both ornithischians and theropods?"

Several commentators on the Tetrapod  Zoology post on ornithoscelidia approach this question and suggest that the ability to bottom feed on aquatic vegetations is a potential reason. I agree, but I would embellish this reasoning with a more dire and immediate consequence: ornithoscelidians did not want to be sitting ducks.

Sitting Duck: A person or thing with no protection against an attack or other source of danger.

Theropods we know were full of air - it is no stretch to imagine that, when immersed in water, they would have floated like a buoy. Maybe not sitting so high in the water as modern ducks but possibly with much of the head, neck, and even some of the back out of the water. This buoyancy would have made theropods excellent patrollers, explorers, and navigators of aquatic environments. It also may have helped in dispersal situations and survivorship of catastrophic aquatic inundations such as tsunamis and the relatively frequent storms surges, tidal inundations, and hurricanes that we should expect in hot house climates.

The floatability in water made diving a little bit difficult but not impossible: for theropods wanting to get under the water they simply point their nose in the direction that they want to go in and enact rear propulsion from the legs and tail. One of my favorite observation recorded of opportunistic hunter/scavenger theropods is of giant petrels (not known for diving abilities) repeated going underwater to scavenge a dead wedded seal.

creditJohn Van Den Hoff & Kim Newberry 2006

This digression also allows me to finally get rid of a piece of art I did quite a while back. Some opportunistic Coelophysis diving to scavenge a dicynodont at the bottom of some recent flood waters. Take note of the opportunistic pterodactyloids buzzing in for dislodged scraps.

Diving For Coins Coelophysis by Duane Nash

What is good for the goose is not necessarily good for the gander. While sitting high in the water may have been a benefit for wide ranging, opportunistic theropods sitting high up in the water for prey animals like ornithischians may have been fatal. And when we look at the earliest ornithischians they were not gigantic, heavily armed, or especially refined cursors. Their niche may have best been approximated by large rodents, small forest dwelling deer and antelope, and water chevrotains (Hyemosuchus aquaticus). It is water chevrotains I want to pay special attention to as here is a small herbivore that utilizes the water to good effect to literally vanish from predators. In the clip below the predator happens to be a modern predatory theropod , the crowned eagle. Also wonderfully narrated by Mr. Honey Badger himself:


Water chevrotains are noted for a thick, dense padding of skin along the rump and around the neck. Skin is actually the largest organ in the body and plays a little heralded but profound role in buoyancy as I discussed in bottom punting Spinosaurus. Readers should note that two other bottom punting specialists - tapirs and hippos - have thick skin and sink to the bottom.

It is quite possible that the earliest ornithischians quickly and resolutely diminished their system of air sacs and pneumatic condition - that in conjunction with thick and sometimes armored skin - allowed them to sit lower in the water. Analogous to water chevrotains and other small mammals that utilize the aquatic medium for concealment these earliest ornithischians set in motion a trend of aquatic concealment that - to greater or lesser degrees - likely persisted throughout their tenure with ornithopods like Thescelosaurus. There is no way to tell at this point where various ornithischians sat in the water - if they achieved true negative density like water chevrotains or if they just sat with more of their body submerged and that was good enough. But the point remains that such animals would have benefited cryptically by sitting lower in the water and dispensing with air sacs.

credit Duane Nash Thescelosaurus hiding underwater from topside threat

But if we assume that the baseline condition for ornithischians was to sit low in the water, when we add density in the form of scutes, osteoderms, thick skeletons, and heavy skulls then we have the likely potential for true bottom-punting, negative buoyancy situations to develop. Among both marginocephalians and thyreophornas we see many likely candidates that may have trended towards  negative buoyancy in these animals.

Water Sports by Duane Nash

For the most part I think bottom punting would have served these animals just fine. They still likely moved with grace and efficiency through bodies of water - they just did not swim in the strictest sense of the word. Moving through relatively shallow streams, rivers, ponds, sloughs, estuaries less than 5 meters deep or so not a problem and waters of this depth would have been what these animals came across in their day to day existence.  Indeed a ceratopsid could easily have been prone to flee into the water when chased by a theropod. The theropod in grave danger from a bottom punting ceratopsid as it floats vulnerable at the surface, its belly exposed to horn thrusts.

However in deeper waters that they could not get up to the surface in that they found themselves in trouble. I am specifically alluding to the ubiquity of ankylosaurid skeletons recovered from oceanic sediments - were these animals taken by sudden intrusions of sea water that put them in waters too deep to kick off the bottom to the surface in? And then you have the infamous ceratopsid mass bone beds, most notably from Centrosaurus that most likely document tremendous inundations of the ocean onto land. Researchers have struggled to explain why Centrosaurus - and pretty much nothing else but Centrosaurus - succumbed to these inundations. The wikipedia web page on the Hilda mega-bonebed summarizes a lot of the work on this topic.

The ubiquity of ceratopsids in these death assemblages is potentially explained by a negative buoyancy for these animals. All the theropods and hadrosaurs in the environment would float away. Ceratopsids were doomed in deep water.

Is there any independent evidence pointing us in the direction of thick skin in ceratopsids? By golly yes there is. Before the world fell in the love with the preternaturally adorable Psittacosaurus soft tissue restoration there was some other work on Psittacosaurus dermis (Lingham-Solia, 2008). What was revealed in the study is that the Psittacosaurus revealed a cross section cut out that had a remarkable density of 40 collagen layers and a skin thickness of .8 inches - which does not sound like a lot but is pretty astonishing for such a small animal. Unfortunately the author behind this work used these multiple layers of collagen to argue that not only was Psittacosaurus not "feathered" - which it wasn't of course - but that the feather impressions recorded on theropods are actually layers of collagen peeling off. The study was pirated by B.A.N.D.I.T. notions and what could have been a perfectly interesting document on exceptional skin thickness got turned into something that it shouldn't have. But let's not throw the baby out with the bath water here. The paper still shows a startling level of skin thickness - among the highest recorded in any vertebrate.



Again, let me hammer that point home, "multiple layers of collagenous fibres in excess of 25, among the highest recorded in vertebrates". There was an arms race in the Mesozoic, or more like it there was a skin race. Prey species attempted to evolve the thickest most durable hide they could to thwart those pesky theropods who more than kept pace in evolving forms more adept at sawing or crushing through thick and armored hides.

There has been some research into this topic of ceratopsid swimming and buoyancy (Henderson, 2014). The work concluded that ceratopsids sat in the water with their heads submerged. On the other hand hadrosaurids were much better natural swimmers with their head above water, hence the lack of hadrosaurids succumbing to such oceanic intrusions. This study points us in the right direction but it left out two things; 1) It did not account or even mention skin - a particularly dense skin may have sunk ceratopsids right to the bottom; 2) Pretty much any large tetrapod that lives in and around bodies of water has at least some capacity to move through bodies of water. Ceratopsids living on coastal Laramidia - especially bordering the western interior sea - would have have come across water all the time - lagoons, estuaries, swamps, tidal channels, rivers. It is absolutely non-sensical that an animal that comes across bodies of water daily has no way to efficiently move through them. Long time readers know that this is a constant theme I iterate on this blog: animals have to make sense. They have to reasonably move through their environment; eat; protect themselves; mate. When you conduct research that points you in the other direction - towards a maladaptive animal ill-equipped to deal with day to day encounters (such as bodies of water) - there is probably something wrong with your scenario. Such an animal, so maladapted to it's environment, would be selected for extinction and not leave a fossil record. Whenever you see a paleontologist utter the phrase "failed evolutionary experiments" run away quickly.

Now some have taken the mantra "most every tetrapod can swim" a little too literally:  I would add the caveat: "most every tetrapod can swim and/or bottom punt". Sinking ceratopsids right to the bottom would at least allow for movement through >most< bodies of water. For a large animal that can bottom punt it can still go through potentially fairly deep bodies of water, at least most bodies of water it will encounter on a daily basis. The problem is when it encounters bodies of water too deep to kick off of the bottom of to reach the surface. Large deep rivers, lakes, and extensions of the ocean can act as barriers to such animals. Or a catastrophic inundation of the ocean. That would be a big problem for negatively buoyant animals.

Bottom punting ceratopsids offers a potential explanation for why these animals were selectively killed while no other dinosaurs suffered comparable losses during large oceanic intrusions. It is not that ceratopsids could not move through water - they could quite well as a bottom punter - it is that in deep water they sank like a stone. It must have been horrific for them when the sea took over the land.

And this speculation is where it gets really cool. Because once you have a geographic barrier thwarting travel - in this case deep water - then you have a potential cause for speciation events. And we all know how wild with diversity ceratopsids on Laramidia got...



Papers

Baron MG, Norman DB, Barret PM (2017) A new hypothesis of dinosaur relationships and early dinosaur evolution. Nature March 23, 2017

Henderson, D. 2014. Duck Soup: The floating fates of hadrosaurs and ceratopsians at Dinosaur Provincial Park, in Eberth, D. and Evans, D. (eds). Hadrosaurs. Bloomington: Indiana University Press. pp. 459-466

Lingham-Soliar, Theagarten. 2008. A unique cross-section through the skin of the dinosaur Psittacosaurus from China showing a complex fibre architecture. RSC Proceedings of Biological Sciences 2008 April 7. 275(1636) 775-780. online

Van Den Hoff, J & Newberry, K. 2006. Southern giant petrels diving on Macronectus giganteus diving on submerged carrion. Marine Ornithology 34: 61-64. online


"A Long habit of not thinking a thing wrong, gives it a superficial appearance of being right, and raises at first a formidable outcry in defense of custom". Thomas Paine

I just can't get away from fleshy lipped theropods...

Recently I went out for a hike in the local Santa Monica mountains. Spurred on by the recent heavy winter rains in California I was expecting a bouquet of abundant wild-flowers. The flowers were there of course and it was breathtaking. However as the strange has an unusual affinity for me (and I for it) what got my attention as soon as I opened my truck door at La Jolla canyon was not the flowers, but a dead hatchling theropod on the ground. Not sure what species - probably a larger corvid due to size - but as I peered closer I noted a strange bundle of flesh at the crease of the mouth.




Some genetic aberration? The avian version of a cleft palate? Or perhaps a link to a more primal ancient pedigree of lipped theropodian monster faces? There is a saying in evolutionary theory: ontogeny recapitulates phylogeny. Is this a case of that? I looked at lots of pics of hatchling birds online and can't find any with that degree of bunched up oral tissue at the commissure.  Whatever your thoughts on what this might represent - probably is some genetic defect - you have to admit the weirdness of it all… a dead beaked bird with a fleshy extension of the oral margin directly reminiscent of the very same depictions I have been advocating.

The picture below is a screen shot from a youtube post by C.M. Kosemen detailing his thoughts on the chickenosaurus. The pic is actually taken from a book titled Incredible Life: A Handbook of Biological Mysteries by William Corliss, purportedly a rare treasure trove of arcane biological curiosities described by Kosemen as " the Necronomicom of biological weirdness". According to Kosemen the book documents a chicken from 1878 born without a beak and having strange "mammalian like head features". The oral tissue surrounding the mouth described as a quasi gummy but tough tissue.


Thanks for commenter Casielles for bringing this pic to my attention and noting how much it resembles some of my lippy theropod designs.

Wherever you fall on the chickenosaurus debate, the Dr. Moreau in me is still curious about what sort of oral tissue would come about on a chicken reverse engineered and stripped of its more derived facial attributes into something well… not quite a dinosaur... but not a typical beaked bird either. Could we garner a glimpse at the primordial oral margin of theropods prior to the evolution of beaks?

The photo below is credited to Bhart-Anjan Bhullar and shows how through suppression of certain proteins the premaxillary bone of a chicken (labelled experimental) can be suppressed giving arise to a more basal configuration.


While the fusion and expansion of the two premaxillary bones into the "beak" is certainly interesting,   all of this does beg the question: if beaks can be reverse engineered into snouts can we also reverse engineer the oral tissue that lines the mouth of birds into what once was?

Bhullar et al. (2015) isolated specific proteins that stimulate the development of beaks (i.e. the premaxillary bone) in modern birds. Although I can find no pictures of the creature that they came up with - from what I gather the birds were not allowed to hatch - they were reportedly able to control these proteins and in doing so reportedly come up with a chicken closer to the ancestral state in terms of facial bones and lack of beak. What they said - and what caught my interest - is that this manipulated chicken skull looked superficially normal from the outside but something obscured a clear look at where the beak should have been. What was obscuring the beak area, you ask? A flap of skin was. Was this flap of skin a reversion to a more primordial "lip" condition? I don't know. What is interesting in this study is that another unexpected osteological change occurred - the palatine bones reverted to a more ancestral condition. Manipulation of one aspect - the beak - can have unexpected correlates in another osteological condition and I'm asking maybe even supporting soft tissue components as well…

credit Bhullar. Showcases loss of beak creates ancestral palatine condition

Take what you will from these studies, they of course have been met with loads of skepticism. But I do have to wonder if they hint at a pathway to a closer approximation of soft tissue oral margins in theropods.


Croc Faced Killers

Croc-Faced Lungfish Fighting Mud Frolicking Spinosaurus by Duane Nash

Of course for those keeping abreast of things it is all about crocodile faced theropods right now. Yep, rugged,  tooth exposed, thin lipped, croc faced killers. And let's give credit where credit is due: Tracy L. Ford has been sounding off on this look for years before the Carr paper hit. You know some might think I am against the notion of croc faced theropods - quite the contrary actually.  I do want to go on record saying that the croc faced idea and lack of lips notion in theropods is a good one and a very important concept and likely prevalent in a great many theropods - just not for all of the theropods that this look is normally attributed to.

A necessary prequel to the ideas I will be elaborating on is my last post Behind Your Bony Mask of Face. In this post I made the argument that the texture of the skull of crocodiles has more to do with ecology than it does skin integument, that in fact a similar skull texture is found on many amphibious and aquatic stealth predators - some that have tightly adhering skin and some that do not. What tyrannosaurids like Daspletosaurus horneri and indeed most carnivorous theropods have is indeed a rough and textured skull that, I suggested, helps anchor a particularly tough and textured epidermis. This dermis - possibly even somewhat keratinized and/or cornfield - is not necessarily covered in scales.

Is there a test of this notion of mine? Can we locate an animal - preferably somewhat close ecologically, behaviorally and phylogenetically to tyrannosaurids - that shares such a rugose and textured skull BUT that does not have a scaled facial epidermis?

By golly, yes there is and it comes in the form of a lineage of theropods that are extinct, were arch hunter-scavengers, did have nasty biting abilities, most certainly face bit, were not aquatic, and were most certainly not scaled in the facial region. The answer is phorusrhachoid terror birds.

Phorusrhacos longissimus Royal Ontario Museum, credit Captmondo CC3.0

Phorusrhacos from here

AMNH 5027 public domain

What I am suggesting is that the facial osteological correlate of these animals is not so much a phylogenetic signal, but an ecological one. Large carnivorous derived theropods (i.e. phorusrhacoids) having a textured skull convergent with their ecological antecedents in large carnivorous extinct theropods. A necessary caveat of this is that, as I mentioned, those theropods that most converged closely with crocodilians ecologically likely had a croc - like oral margin and skin texture. These theropods would most notably include spinosaurids. Other small game theropods especially of the "kink - snouted" gestalt may have been similar or split the difference: lack of extra-oral tissue towards the front of the jaw but retaining some "lip" towards the rear of the jaw. Noasaurids which were always scrounging into the dirt after fossorial prey may have diminished lips as well. Many smallish coelurosaurs, dromies, troodontids, and compsognathids that were small prey scroungers may have followed this pattern of diminishing, receding lips and a more croc-like exposed oral countenance.

Toothed Birds, Pseudo-toothed Birds and Small Game Foraging To Lose Lips

Sinosaurus credit Duane Nash

Sinosaurus has always been a favorite of mine. It looks basically like a more beefed up version of Dilophosaurus. But while Dilophosaurus' more slender teeth and jaws denote a theropod very much engaged with a prey base of smallish stuff and quite possibly dedicated piscivory - Sinosaurus looks like an animals unsatisfied with small fry and aiming at bigger game. However it still has that odd kinked snout in the front which suggests that it could optimally pluck at small game or perhaps evolved from something of a more Dilophosaurus gestalt, but ultimately was more turf than surf in its diet. To reflect this dichotomy of kinked snouted theropods I diminshed the extra-oral "lip" towards the anterior kink of the jaw but retained more fleshy, salivating meat curtains towards the rear.

Sinosaurus credit Ghedoghedo

Returning to Dilophosaurus we are presented with a conundrum similar to saber-toothed predators and extra-oral margins. It has slender, but very long teeth. Actually this is a case where the teeth from the upper jaw penetrate below the level of the neuromuscular foramen of the lower jaw - and actually might dip below the lower jaw itself. Unless of course the teeth in this lower pic by Jaime Headden are actually protruding too much ( I suspect they are). This creates a very dastardly situation for lower lips and looking at Dilophosaurus it might in fact be a true croc-faced killer!!

Jaime A. Headden (User:Qilong) - http://qilong.deviantart.com/art/The-Dilophosaurus-Yawn-252396964

Again with Dilophosaurus it is simple to formulate an ecological reason for it dispensing with lips. Because it shows tendencies towards small game, large lips in the anterior of the jaw would provide a cumbersome block to intricate poking and plucking of small critters whether in the water, in burrows, or whatever. Better to dispense with such lips, evolve a keratinized and/or cornified oral epidermis epidermis and retain sensitivity from the neurovascular foramina. Note how this parallels the argument in my last piece in this series where I suggested that the evolution of beaks and loss of teeth were coincident with an increasing emphasis of omnivorous/herbivorous diets. Where as the constant pecking, plucking, and cropping of seeds, fruitifications, foliage, insects would encourage a beak type oral margin to replace non-muscular fleshy "meat curtain" type oral margins in  theropods: in croc-faced killer theropods the lips would likely recede for the same basic reasons. In these small game hunting theropods the constant abrasion against substrate, the drag imposed on lips in water, the delicate plucking of small game would encourage a loss of extra-oral tissue. Like theropods that evolved beaks, theropods that moved towards specializing in small game, burrowing animals, "piscivory" would lose lips but they would not lose their teeth.

A constant argument I put forth for large lippy extra-oral tissue in large game theropods is that this tissue provides an extensive "neural net" that allows real time sensing of the movement of large prey in the jaw and corresponding bite adjustments. For theropods foraging for smaller prey in the water such a "neural net" is not needed. Water itself provides the medium for sensing prey movement and as the lips would hinder small game plucking, encourage drag, and are altogether redundant they would soon diminish and take on a "croc-like" oral gestalt. The sensitivity remains however, it is just the lips that recede.



It is also possible a very tough gummy type tissue covered up a lot of the tooth in Dilophosaurus. Such gummy tissue would of course be a lot more rugose and resistant to drying than typical gingiva but still anchor and strengthen the teeth.

Teeth, or better yet pseudo-teeth are important for both extinct and extant proper aves and near birds like the often toothed enantiornithines. There are many examples of the evolutionary utility of teeth, choannal papillae, and pseudo teeth in these animals showing us that not only are such projections useful and whenever possible retained BUT more importantly, I would argue, that there is no universal a piori directive, guidance, or eventuality of an edentulous "beak" in theropods. These examples also fundamentally address the importance of ecological consideration when thinking about extra -
oral margins and "toothiness".

Pelagonis mauretanicus crédit Didier Descouens CC4.0

I have to start off with the most obvious choice: the giant pteranodontid mimics, the pelagornithids. Their non-serrated toothlike extensions of the skull bone and rhampotheca just beg for us to consider the ecological utility of teeth in such marine, soaring predators. They also compel us to wonder if toothless pterodontids were not quite so "toothless" and that maybe they evolved a soft tissue choannal  papillae pseudotoooth and/or sharp tongue tooth replacement of their own. If birds were not winnowed down to the toothless beaked species through the K/T extinction one has to wonder if legit toothed birds would not dominate the oceans, like they did in the Mesozoic?

Pseudo teeth penguin credit: http://i.imgur.com/o3vze.jpg

Pseudo-teeth on penguins are a thing. Remember, penguins stem from a fairly early branch of avians and possibly even arose in the Cretaceous (although I doubt it due to competition from hespernornithids) but there are no truly toothed penguins that we know about from the fossil record. This reinforces the idea that only edentulous beaked avians made it through the K/T and had to reinvent teeth when they occupied niches where teeth come in handy.

To bolster this pattern simply look towards the dominant fish eating birds around in the Cretaceous: hespernornithiformes and ichthyornids both have toothed jaws. They had basically lipless keratinized beaks - as should occur given their predilection for aquatic prey. Yet they retained teeth. And there is no reason to suspect that they would lose their teeth if the K/T event did not occur.

Hespernornis regalis YPM 1206 credit Heilmann 1926

It is worth mentioning that in the above species it has partially lost teeth in the upper jaw, replaced by sockets that the lower teeth slot into. Ichthyornis shows a similar pattern: tooth loss partially in the upper jaw but a continuous row of teeth in the lower jaw. One has to wonder if and why we should expect complete tooth loss in these groups given the propensity for truly toothless birds to evolve pseudo-teeth.

Ichthyornis public domain credit O.C. Marsh

I would be remiss not to put a word in for enantornithines, the true champions of tooth retention in birdy types. They count in their number a fair bit of smallish, predatory type toothed opportunists and specialists. They also, as should be expected, probably had extremely reduced and receding lips to better pluck and peck at small game. But alas they did not make it through the K/T as successfully as true avians perhaps because they did not fully commit to seeds and the ubiquitous "pecking" foraging method so emblematic of modern birds?

credit Stephanie Abramowizc

Indeed, far from showing a tendency to lose or diminish teeth many enantiornithines were going full hog with toothiness. Sulcavis geeorum had some pretty gnarly, crazy teeth seemingly well adapted for chewing up tough crustaceans and insects.

Sulcavis geeorum credit Stephanie Abromowicz

Jingmai O'Connor:

"While other birds were losing their teeth, enantiornithines were evolving new morphologies and dental specializations. We still don't know why enantiornithines were so successful in the Cretaceous but then died out - maybe differences in diet played a part."

So where does this leave us? Admittedly this piece is a little all over the place, and readers might be dumbfounded in how quickly I switch from say a critter like Sinosaurus to Pelagornithis. But there are some general themes and trends that stand out.

- The transition of toothed birds to toothless bird is not a direct line nor is it necessarily inevitable. The prevalence of pseudo-teeth in many modern birds (especially piscivorous) that correspond to toothed Cretaceous analogs should give us moment to pause. Perhaps the Cretaceous toothed ichthyornids and hesperornithiformes with their basal retention of teeth were not the inferior models compared to modern penguins and "gull" type seabirds but actually the optimal model due to their teeth which should outperform the pseudo-teeth of modern birds.

- Enantiornithines provide us with an alternative universe where toothy birds are not only common but the most successful "norm". We might be partially conditioned to think of modern derived toothless birds as the optimal model for what a bird should be, but what if this is not the case? Enantiormithines seemed to dominate toothless birds in the Cretaceous. Did the K/T boundary provide the ecological filter that allowed toothless seed eating birds to get through but prohibiting the more toothed - and carnivorous - enantiornithines from getting through as has been suggested in a recent paper?

- In both the toothed fish eating birds and the carnivorous enantiornithines I would put forth a condition of highly reduced lips - perhaps just a trailing edge of tissue at the commissure. This is also similar - albeit without a beak - to the near lipless condition I would expect in small game hunting, fossorial foraging, and piscivorous theropods. The realities of aquatic foraging, constant abrasion, and intricate plucking of small game would create a less than ideal situation for any substantial, non-muscular extra-oral tissue in these animals. This provides an alternative pathway to losing lips to what I discussed in my Lips Before Beaks part I where herbivory would diminish lips and create beaks in theropods.

In all the above examples I am actually explicitly arguing for an exposed toothed, primarily lipless, and even croc-like oral margin. Wait a second here… wasn't I the guy who argued for lippy sabertooth cats,  beneficial activity of saliva on tooth health and what not? Have I done an about face?

Let's just say that my thoughts have… evolved and become a bit more nuanced. Two things can be simultaneously true and seemingly at odds but still coexist. Sheathed teeth under the auspices of calcium and phosphorous buffered salivary broth I still believe is a great thing to have… just not mandatory in all cases. Pterosaurs, crocs, plesiosaurs they all break that "rule" and a good many theropods probably did too… just not all of them. I would still consider most largish big game, serrated toothed macro predatory theropods to maintain - and even re-evolve - large "meat curtain" type lips. This would include most largish tetanuran type theropods, allos, carchs, predatory ceratosaurus, tyrannosauroids, dromies, megaraptors - generally most serrated toothed zyphodont theropods.

You will note I left out abelisaurids, I think something neat was going on with them which I will save for another post. Yep, some have been asking for it and I finally have enough new ideas to make a post on abelisaurids. Trust me, they will be weird AF when I'm done with them. Weirder than they already are.

And finally I leave you with Austroraptor. It was a South American unenlagine potentially flightless spinosaurid mimic.  Remember spinosaurids themselves are crocodile mimics and share with them a skull texture (spinosaur skull texture is more similar to crocs than tyrannosaur skull texture is to crocs imo) and likely a lipless oral margin. Guess what the skull texture of Austroraptor looks a bit like?

Austroraptorcabezii by Duane Nash

Austroraptor is that unique beast that potentially tells us a lot. Because it was a maniraptoran and quite possibly secondarily flightless it may indeed hail from fully feathered ancestors. If it lost feathers on the face it may have indeed followed the trend of modern naked faced birds and eschewed feathers and scales on the face. After converging with spinosaurids (which converged with crocodiles) it evolved a highly, rugose, textured, and pitted skull. Not because it had a scaly face but because such a skull texture allows - as I suggested in Behind Your Bony Mask of Face - better tactile and neurosensory capability as a sensitive snouted aquatic predator. Hence the convergence of skull features as I highlighted in such disparate groups as temnospondyl metoposaurs, phytosaurs, snapping turtles, crocodilians, various fish, and others. These textured skulls in aquatic predators I hypothesize allow more surface area to "catch" vibrational frequency in the water medium like a gnarled, old used catchers mitt.





Refs

Bhullar, B.-A. S., Morris, Z. S., Sefton, E. M., Tok, A., Tokita, M., Namkoong, B., Camacho, J., Burnham, D. A. and Abzhanov, A. (2015), A molecular mechanism for the origin of a key evolutionary innovation, the bird beak and palate, revealed by an integrative approach to major transitions in vertebrate history. Evolution, 69: 1665–1677. doi:10.1111/evo.12684

Skiorpovenator by Duane Nash

I told you that this was going to be a weird one, that I will be going out on that speculative branch and perhaps sawing it off. But I believe there is a sliver of a suggestion of a possibility that those bedeviled architects of weirdness the abelisaurids are even stranger than we are already allowing them. That they may in fact hail from a primarily omnivorous antecedent  - with a special dietary emphasis on various gymnosperm "fruitifications" from cycads, ginkgoes, podocarps - and that even the more derived carnivorous abelisaurids carried on with a significant component of "frugivory" and were important seed dispersers and maintainers of sauropod gardens. Long story short, that abelisaurids may in fact be secondarily carnivorous.

Was Ken Ham inadvertently prescient?!?

accidentally prescient? Ken Hams Garden of Eden Carnotaurus

What the hell you smoking Nash? How do you get a herbivore from this animal? Look at that mug?!?

Bear with me as I make the case. I don't necessarily plan to or expect to convince you… merely open your mind to the idea… maybe.

Aucasaurus credit FunkMonk CC2.0

Clue #1 Those Puny Vestigial Arms

Abelisaurids have arms that make T. rex look like Arnold Schwarzenegger. If you asked an abelisaur "which way to the gun show?" it could not even point you in the direction. While tyrannosaurids and other predatory theropods like carcharodontosaurids had somewhat reduced arms they still had functional arms. We might debate what if any role they played in prey capture, if they were used in ritualized combat, mating, or primarily hauled dinosaur brisket back to feeding layers, but it is very evident that predatory theropods - with the exception of abelisaurids - could do stuff with them.

Senter 2010

I think that point should be iterated again become I notice some conflation of the two notions of vestigial and reduced in theropods - reduced is not the same as vestigial.

Abelisaurids arms were infinitely useless in any sort of combat - although I do hold out the possibility that they were useful in dinosaurian foreplay heavy petting sessions - and most assuredly represent a genetic defect that became established in this lineage of theropod. According to this article by Brian Switek the work of Alexander Vargas (Switek cites an unreferenced paper from 2002 although I have faith in this idea as I have heard it referenced before) suggests that abelisaurids underwent a mutation in two genes that regulate the formation of the forelimb: HOXa11 and HOXd11.

This mutation, I presume (correct me if I'm wrong in the comments), is the same or similar to the genetic defect that gave diminutive, vestigial forearms to; Limusaurus; kiwis; cassowaries; Aepyornis (elephant bird); and moas. The proliferation and transmission of a genetic defect is of no real evolutionary consequence flightless birds. In the case of Limusaurus it is trending ontogentically into a herbivorous/omnivorous lifestyle and loss of a raptorial forearm grasp is of no special consequence either.

Moving from this observation it is patently obvious that predatory derived abelisaurids are very distinct ecologically from all other theropods and derived flightless avians that underwent mutations resulting in vestigial arms or wings . It is also very probable that this mutation - or ones that result in similar outcomes - arose in many lineages of theropods. But it is striking that in only one lineage of arch-predator theropod did this mutation take root - abelisaurids.

One of these things is not like the other, one of these things is something else…

With all of those diverse lineages of predatory theropods rummaging around during the 140 million years of the Mesozoic why did solely abelisaurids take on and proliferate a mutation that, it seems reasonable enough to presume, other predatory theropods were routinely exposed to?

I know evolution is not perfect and that sometimes negative mutations do get root and proliferate. But I'm still left with the stumbling block in this scenario of other theropods reducing (keep in mind reducing is different than vestigial) forearms like tyrannosaurids and even some coelurosaurs and maniraptorans, but only abelisaurids threw the arms away to the evolutionary scrap pile.

It seems logical to me to suggest that abelisaurids accepted the conditions of this genetic defect not when they were mighty titanosaur slayers but when they were piddly omnivores yet to be kings, more prone to feast on cycad fruits than sauropod entrails. If deeper in their ecological history abelisaurids were of a more omnivorous bent that could potentially explain how such a mutation could take root in animals that did not require strong raptorial forearms for their lifestyle and is more in line with the pattern of other vestigial arm reductions in theropods that have no special use for their forearms (i.e. kiwi, cassowary, moas, Limusaurus, Aepyornis). It also explains why no other predatory theropods got vestigial arms - as primarily predators this deleterious mutation would always be eliminated from the gene pool.

Clue #2: Signals of an Ecologically Adventurous Ceratosauria Being Received From the Jurassic

Limusaurus credit Levi Bernardo CC3.0

After the jarring sensation from the initial wtf of the idea has washed over your brain cells what should immediately come to your mind is that ceratosaurs, it has become increasingly evident, were up to some pretty weird stuff getting into the Jurassic. Limusaurus is, for me, the gift that keeps on giving. Not only does it readily encapsulate in one tidy ontogenetic sequence the transition from a predatory lifestyle to a herbivorous one complete with parallel loss of teeth, growth of beak, and arguably loss of extra-oral "lippage" but it cries out loud and clear: "We all were not scarfing on bronto guts! You should expect more of us!!"

There is every reason to suspect that, largely obscured by the passage of deep time and lack of early-middle Jurassic exposures, there was quite the adaptive radiation of ecologically diverse ceratosaurs in that period of time. Many of which were experimenting and exploring non-traditional theropod ecologies. Could the putative ancestral abelisaurid been such a dietary deviant? Other members of elaphrosaurinae should also get a nod here as they too have been suggested to be deviating from the norm in terms of lifestyle but alas no heads have been found.

Although elaphrosaurinae are currently understood to be a sister group to abelisaurids the possibility is there that somewhere deep in the pedigree of abelisaurids is perhaps an animal more prone to frequent the salad bar than the sauropod prime rib carving table.

But wait a second we already have this animal, we have Eoabelisaurus and it is just another good ol' meat chomping abelisaurid….

Or is it?

Clue # 3 Eoabelisaurus May Not Be the Meat Chomper We All Assume It to Be

When Eoabelisaurus was first revealed it was hailed as a lazarus taxon, evidence of a cryptic lineage of abelisaurids going back 40 million years earlier than the next oldest member. Personally I was always suspicious of such a long tenure of seemingly unchanged abelisaurids. Save for the shrinking forearm nothing much seems to change from Eoabelisaurus to Rugops. Of course such stasis is not beyond the pale, perhaps that is just what happened. But I have my doubts about Eoabelisaurus. I am not in doubt that it was an early abelisaurid, I am in dount that it was just another good ol' meat chomper. The reason I say this is because of some characteristics of what we have of the skull. Or what we have left of the skull.



Like any good mystery we don't have any of the tooth row from the dentary or maxillae recovered from Eoabelisaurus. What we do have are some elements from the roof and back of the skull. And why they are interesting to me is not for what they have but for what they don't have. Missing are the thickened lacrimals, postorbitals, and overall thickening and rugosity of upper skull elements so characteristic of large predatory theropods and especially every other abelisaurid yet known. In Eoabelisaurus these elements are not thickened nor is notably ornamental:

From the paper (Pol & Rauhut, 2012):

"The skull roof is not notably thickened and no cranial ornamentation is present."

It's long been a contention of mine that the thickened and gnarly skull roofs of large carnivorous theropods primarily serve as sinks for stresses and strains incurred along the tooth row. I have wrote about this idea here and there are some converging lines of evidence that point in this direction.  Such thickened skull elements are not found in theropods that transition into omnivory/herbivory from carnivory. I don't take the suggestion that thickened skull roofs were primarily used for head butting competitions seriously. No studies have been conducted pointing in this direction.

Display was a secondary function I contend. The recent paper on theropod skull ornamentation (Gates et al., 2016) linked cranial ornamentation with increasing giantism in those species that had cranial adornments. What the paper failed to do was consider that biomechanical stresses may have increased the likelihood of thickened skull roofs and consummate adornments.  In fact the pattern that they elucidate - cranial ornamentation linked to increased giantism - is essentially what should be predicted if these same structures served a primarily bio-mechanical function. If the function of such skull ornamentations is primarily for display we should expect such a positive feedback loop to create the largest and most elaborate osseous display features to occur in the most derived theropods. In fact the opposite seems to have occurred. The osseous displays of tyrannosaurids, abelisaurids, and carcharodontosaurids are relatively subdued compared to the earlier and more dramatic osseous display features of guys like Dilophosaurus, Crylophosaurus, Sinosaurus, and Ceratosaurus. Guanlong, an early tyrannosauroid, has much more elaborate head crests than later tyrannosauroids. Of course I think later and larger theropods largely replaced osseous display features with more dynamic, striking, and communicative soft tissue features (hello flesh antlers) but that is for another time. The paper also made the error in positing that Acrocanthosaurus lacked osseous cranial adornments & thickened skull roof when it most obviously does. In fact all large, macro-predatory ziphodont skulled theropods have thickened skull roofs often times parlayed into cranial adornments. Certain tyrannosaurids and abelisauruids even fused some of the skull roof bones together for better stress absorption. All known abelisaurids had such gnarly, thickened skull roofs. All except for Eoabelisaurus that is.

Now you may take this reasoning with a grain of salt, the jury is still out on what was the reason for thickening of the roof of theropod skulls. But what can't be disputed is that Eoabelisaurus differs fundamentally in this aspect from not only all other abelisaurids but all other large predatory theropods as well. Eoabelisaurus was perhaps not the rugged and strong biter that later abelisaurids were. It was possibly not wrestling large sauropods with that jaw. This is the best why? that I can currently come up with.

Clue # 4 Those High, Short Snouts

It has long been recognized that abelisaurids have some freakin' weird heads going on. The contrast in skulls is striking against other predatory theropods. Other large predatory theropods have narrow, long, and low snouts while abelisaurids have high, wide, and short snouts. Traditionally this difference has been explained as an adaptation on the part of abelisaurids to bite on and hold to prey as opposed to bite and slash of other theropods. My question is what is the best exaptation that would set this trend in motion?



A potential explanation that may have initially shifted abelisaurids to this shape is that it was not selected for under the auspices of a hyper-carnivorous ecology but a selective omnivore. Such a short blunted skull could better pick, pluck and select choice bits of plant matter (especially reproductive propagules), small animals, eggs etc etc. Sort of like the skull of Avimimus but still toothy and retaining some predatory ability. Later on in their evolutionary tenure when abelisaurids ramped up their carnivorous inclinations the short high skull was an exaptation towards their divergent jaw and biting style among theropods. Omnivory offers a potential explanation for why abelisaurids jaws and biting style are so different from other carnivorous theropods.

credit GhedoGhedo CC3.0

Clue #5 Gymnosperm - Titanosaur - Abelisaurid Ecology

educational use. Podocarpus nakaii credit Ming Weng

Of course I should stipulate that a putative omnivorous ancestral abelisaurid was always a herbivore with second thoughts. They never committed full hog to herbivory; probably did not take up gastroliths; did not digest cellulose; they obviously did not push back the pubic bone and expand the guts to ferment large piles of roughage. Their primary exploration of herbivory I suggest would have consisted in the high quality reproductive propagules, the "fruit" if you will of such gymnosperms as cycads, podocarps, and ginkgoes. Plants that were very emblematic of Gondwana and that in a diffuse coevolutionary feedback loop may have enlisted the help of abelisaurds and other tetrapods to swallow, distribute, and germinate their seeds. This coevolutionary relationship may have persisted in the younger, more derived, carnivorous abelisaurids. While Laurasia was exploding in theropod and ornithischian diversity it always seemed like Gondwana was a bit of an ecological throwback to late Jurassic times. Indeed the stasis of  the gymnosperm - titanosaur - abelisaur ecological relationship that seems to have stuck around for a long time in Gondwana may in part be due to abelisaurids helping maintain sauropod gardens.  Indeed where better than the rich phosphorous dung of a carnivore - even better than herbivore dung - to germinate from.

Here is a good review of the "false fruits" of the Mesozoic.

credit Brewbooks flickr. Lepidozamia peroffskyiana cycad

This omnivorous heritage and potential maintenance would have potentially caused a receding "lip" at least on the upper jaw to allow better fine tune biting and grasping of small reproductive propagules. The lower jaw may have retained a bit more of the "meat-curtain" look, especially as large lower lips would have aided in tactile input while engaging with large prey via a neural net.

What would such a putative ancestral omnivorous abelisaurid have looked like? Probably not too different than derived abelisaurids. Actually I would take the general body plan of abelisaurids and plop on a head a little smaller, less muscular, no thick skull roof, little cranial ornaments, teeth fairly small and homodont although not necessarily non-serrated, and give it good running legs as it is now a prey animal. Such an animal was probably gorging on gymnosperm propagules when available but during the offseason dining on eggs, small game, hatchling dinosaurs often swallowed hole, carrion and just taking it easy living the easy life. We do know that abelisaurids grew pretty slow and possibly had a moderate paced mesotherm lifestyle (Ratsimbaholison, 2016). Indeed this slow paced, boom and bust lifestyle may have served these animals well. The ecology of cycads which are likewise slow metabolism plants (yes plants have metabolisms) may in fact be mirrored in one of their chief dispersal agents. Just lounging around, soaking up rays, waiting for either the next crop of cycad fruits to come into mast, the next egg laying season, or the next titanosaur to drop dead. You know, living the bear necessities.

hypothetical ancestral omnivorous abelisaur by Duane Nash

The notion of secondarily carnivorous abelisaurids - and other "carnivorous" theropods - that augmented their mainly carnivorous diet with various high quality plant propagules is adventurous but not really beyond the pale when we put the idea in context. Ecological slosh between carnivory and frugivory is certainly a trend and frugivory seems like an ideal transitional stage to more dedicated realms of herbivory. We now know of crocodiles eating fruit and who knows how often this goes on in the wild? Specialist fruit eating monitor lizards are definitely a thing. There are several vultures that augment their diet with fruit and specialists like the palm nut vulture. Mammalian carnivorans flip flop between eating fruit and animals all the time, some becoming ultimately more tied to vegetable resources. Maned wolves are now known to be particularly fond of fruits. On the other hand polar bears are a good example of a secondary reversion to a mainly carnivorous diet from an omnivorous brown bear antecedent.

I also should at least mention the often noted rotten flesh/cheese smell put off by ginkgo fruits. The mind intuitively drifts to ideas of these Mesozoic relicts enlisting carrion glutton theropods to help consume and disperse seeds.




Rugops The Inflatable Face Monster 

For having such a cool sounding name Rugops is one of the more vanilla looking abelisaurids on first impression. I mean don't get me wrong, it still had the rugged textured skull and strange proportions of abelisaurids but it was no Carnotaurus. First impressions can be deceptive however and if we peer closer at the skull roof - which compared to other abelisaurids is pretty bereft of ornaments or gnarly rocky outgrowths - there is evidence of potential for soft tissue ornamentations.



This evidence comes in the form of parallel rows of foramina on either side of the dorsal aspect of the skull. These foramina, quite apparent on the top picture, could have fed display structures.  I'm not the first to notice this, Paul Sereno has speculated as such and taken note of them, although if I recall he thinks they might be keratin outgrowths. Additionally the dorsotemporal fenestra show adequate size and shelving to support additional soft tissue structures ala flesh antlers.

While many in the paleo-community (at all levels) have been generally recalcitrant to acknowledge and entertain the possibility of such features, this conservatism is not surprising to me. And you know I'm not waiting for them either or asking for their permission either. Give that Rugops a crazy looking engorged facial tissue nightmare rape face.

Rugops Tentacle Face by Duane Nash

As I mentioned earlier when discussing the paper on osseous display features linked to theropod giantism (Gatres, 2016) why would such osseous display features - if they were so significant in spurring theropod evolution and giantism - seemingly diminish in size over the course of theropod evolution? The answer, I posit, is that such features did not so much as diminish in size but become replaced by more useful flesh and skin derived display features. Such features have the advantage over osseous display features in that they can; become engorged with blood thus changing size, shape and color and highlighting changes in mood and intent; can become damaged and re-heal, unlike osseous crests that - if bitten into - can open up the skeletal system to infection BAD!!; and serve an enhanced  thermal function.



You Don't Want To Get Bit By an Abelisaur

I have to admit to developing a heavy dose of skepticism with regards to any study that gives "teh absolute bite force" of an extinct animal. I consider this akin to studies that purport to give "teh absolute speed" of an extinct animal. What I do consider such studies useful for is to give us a good range of powers/speeds but to posit an absolute number is untenable in my estimation and somewhat presumptuous. First of all let us remind ourselves that coming up with really good bite force numbers and speed estimates for living animals is notoriously hard and often changes. That should be mentioned. Secondly when we get past all the metrics, fancy math, moment arms, and finite analysis we are always left with a basic physiological question - are we talking about slow twitch muscle or fast twitch muscle? More to the point what is the relative abundance of either type of muscle - slow twitch giving more of an endurance type benefit and fast twitch more of an explosive burst of power type benefit. There is no way to decipher the relative abundance of those two muscle types from the fossil record. It is their interplay has a profound influence on questions of power, speed, endurance etc. etc.

Discussion on abelisaurid biting style are all over the place; they are called quick weak biters; sometimes Rugops (whom always seems to get picked on) is called an obligate scavenger; some call them tyrannosaurid mimics; Carnotaurus is called a weak and quick biter of only small prey. What and how were those maws operating?

I actually think that the wikipedia page on Majungasaurus summarizes the basic abelisaurid biting style quite nicely (seriously some dino-wiki pages are becoming fantastically informative kudos to the people putting in work). They were bite and hold predators. A strange paradox of the skull is featured in these animals - unlike any other predator. A thickened and stout upper jaw, a pug nosed crocodile if you will, combined with a lower jaw somewhat more slender looking and kinetic, like a snake. While struggling with prey the upper jaw could withstand extreme stresses while the lower jaw would bend and flex to prevent catastrophic damage and fracture. A rather neat and ingenious combination that differs from all other theropods and all other tetrapods that I can think of. That's my thinking as of now. Not my idea, I just happen to agree with it.

What about that small prey specialist niche for Carnotaurus? I think the idea should get some attention because the teeth in lower jaw look fairly slender, however they are not really that bad and could have been strengthened by being partially enmeshed in thick gums. More so than that the neck is just tremendously powerful looking and it has no other attributes of a small game specialist. On an ecological note where are all the modern large terrestrial small game specialist predators? Seems to me once you get much bigger than a coyote you tend to go after animals as big or even bigger than yourself - at least terrestrial predators. I mean there are no lion or bear sized mammalian predators that eschew hunting ungulates and only chase rabbits? Reminds me of the story of phorusrhacidae evolving two foot long skulls and growing eight feet high just to chase big rodents and somehow at high speeds have the skill and preternatural accuracy to conveniently slam their beak tips down on the back of the skull of their small, more agile, zig-zagging fleeing  prey. Yup, I think the notion of giant terrestrial small game specialists is exactly what it looks like - a fairy tale - for both Carnotaurus and terror birds. Gigantic small game specialists are a thing in the water, but due to the unforgiving nature of moving around at 1 G on land large sized small game terrestrial specialists I would put forth as a fairy tail that, unfortunately, a lot of teh professional believe in (he-he-he). It's just not a physically and ecologically tenable existence.

credit Canale et al. 2008

Check out the skull of my favorite abelisaurid, the little heralded Skiorpovenator. Not only is it fairly complete, it has that gnarly bony buttress above the orbits and it has just a weird looking freakish jaw geometry. It also has what looks like some attachments for some fairly large pterygoideus muscles on the lower jaw which what I gave it in my depiction. I would not want to get bit by an abelisaurid.

Skiorpovenator by Duane Nash

Well that about wraps it up for this one. I can't help but remember when first learned about abelisaurids as a young lad reading Gregory S. Pauls Predatory Dinosaurs of the World. So little was known about them then and it is interesting to see just how many specimens have came to light since then, and what still awaits.

The end… for now.



refs

Agnolin, F., & Chiarelli, P. (2009). The position of the claws in Noasauridae (Dinosauria: Abelisauroidea) and its implications for abelisauroid manus evolution Paläontologische Zeitschrift, 84 (2), 293-300 DOI: 10.1007/s12542-009-0044-2 

Gates, TA, Organ, C & Zanno, L. (2016) Bony cranial ornamentation linked to rapid evolution of gigantic theropod dinosaurs. Nature Communications 7. September 27, 2016. online

Pol, Diego & Rauhut, Oliver W.M. (2012) A middle Jurassic abelisaurid from Patagonia and the early diversification of theropod dinosaurs. Proc. Biol. Sciences August 2012 279(1741) 3170-3175 online

Senter, P. (2010). Vestigial skeletal structures in dinosaurs Journal of Zoology, 280 (1), 60-71 DOI: 10.1111/j.1469-7998.2009.00640.x


"A Long habit of not thinking a thing wrong, gives it a superficial appearance of being right, and raises at first a formidable outcry in defense of custom". Thomas Paine

Depending on how you deeply you read into the title of this post it can be not only a double but a triple entendre.

 "How many angels can dance on the head of a pin?"

Can be rephrased as "how many T. rex scales can fit on the head of a pin?"  That is the size of a millimeter and that is a little more than the average size of the T. rex "scale" documented in the recent Bell et al. (2017) paper that has got everyone flummoxed from here to kingdom come. Another visual is that more than 20 T. rex scales can be lined up across a penny. Take home point: these "scales" were small.

From Bell (2017) Note the scale bars in C & E are 5 mm while the scale bars in G & H are 10 mm. These scales were minuscule!!

I think such dramatic issues of scale have been a bit washed over in the more hyperbolic proclamations  of the scale loyalists: "Yes, we have won!! Good riddance feather nazi elves!!" versus the recalcitrant permutations of the suddenly defensive feather crowd; "This tells us nothing new"; "Taphonomy washed away the feathers"; "Maybe T. rex had a feathered petty-coat?" Now I don't mean to mock such ideas and criticisms on the part of the pro-feather contingent but one can't deny there has been a palpable shift in sentiment from mainly feathered to mainly scaled in tyrant lizards (and by extension other largish theropods). Ironically many of the charges leveled at "awesomebros" or JP stylized scale loyalists are now being charged at the pro-feather faction; clinging to an ideal; putting an aesthetic before data; emotional attachment etc. etc.

Things are definitely a bit more unsettled and chaotic than many are comfortable with. Which is something I have been highlighting for some time in this blog; things are going to be getting more testy; a bit more non-consenus; a bit more uncomfortable for some time before things start to simmer down. Most of all things are going to be getting a bit weirder.

And those Wyrex scales are awfully weird. As I highlighted at the top of the post they are ridiculously small. Mark Witton called it the "Revenge of the Scaly Tyrannosaurus" in his blog post on the topic. If this is revenge via sub-millimetere "scales" it is perhaps the most underwhelming revenge story ever told. Sorry, I've had pimples bigger than those scales. I mean they are freaking small?! What is up with them? To put the size of these scales in perspective they are approximately equal to gila monster scales - komodo dragon scales would dwarf them. For all intents and purposes T. rex adorned in these minuscule scales would look pretty much nekkid. Especially so considering the absolute lack of any larger feature scales, larger keeled scales, osteoderms etc etc. Now, jokes about the puny size of T. rex scales aside, I do agree with Mark Witton on major points - and I'm glad he made this jump - that naked hided tyrannosaurids are not only a defensible option, but a likely one. He also raises the pertinent question - again something that I've been clamoring for here for a while - that many larger traditionally feathered dinosaurs may have lost significant amounts of fluff upon attaining larger size  (I do have some reservations on the osteological correlates for large facial scales that Mark seems to abide by but that is for another time). Another pertinent read is Andrea Cau's post on the subject. He makes some very valid and strong arguments, as he has for some time now, that taphonomy is key to a more detailed understanding of the nuances for feather, scale, "integument" preservation. Cau also raises issue with the strange shape and morphology of these scales - an observation I share and if you read the comments on his blog and know my history you can already probably guess where I am going in this piece … C-----A-----R-----U-----N------C…..

I don't know of any concrete studies linking scale size to body size but intuitively such a connection makes sense. I mean larger crocs have larger scales, larger monitor lizards have larger scales, larger boas have larger scales. That is just my off the cuff observations and I'm sure there are exceptions. But, generally speaking, scale size in a related group should get larger as the animals get larger both ontogenetically and in between related species. Did tyrant lizards break this pattern? Should smaller specimens have even smaller scales? Or are they all the same size regardless of size/species? The connection between scale size and body size both ontogenetically and between related species is probably a topic rife for potential studies.

*Turns out there are some studies linking scale size to body size. I went back and read the chapter of hadrosaur integument, authored by a certain guy named Bell, from the epic Hadrosaurs book from Indiana University Press and came across this gem which I will put here:

from A Review of Hadrosaurid Skin Impressions

"Scale morphology (especially scale counts) in modern squamates and crocodilians is typically conserved intraspecifically and is highly important in species identification (Spearman 1973; Brazitis, 1987; Hall, 1989; Cox et al., 1993; Charette, 1995; Branch, 1998). However, scale size (inferred by the inverse relation to number of scales) has been shown to vary positively with body size in some lizard species (e.g. Scleroporus, Ouferio et al., 2011). Similarly, body size (and hence, scale count) is variable both intra- and interspecifically among some squamates in relationship (both positive and negative) to Bergmann's Rule (i.e. body size decreases at lower latitudes or in warmer climates), which is correlated with minimum annual temperature and aridity (Sears and Angilleta, 2004; Oufiero et al., 2011). Despite these variations, scale morphology is one of the most reliable in the identification of extant squamates and crocodilians, especially in closely related species (Brazaitis, 1987; Charette, 1995). It is notable also that tarsal- and toe-scale patterns have been used successfully to identify individual species of extant avians, particularly raptors (Clark, 1972; Stauber, 1984, 1985; Palma, 1996)."

It is useful to note that the above paragraph is couched in a general discussion asking "can scales be used to identify individual hadrosaur species?". The promise for this sort of inquiry is great for hadrosaurs. For tyrannosaurids - as I will get into below - the promise for this sort of species identification based on scales is not looking as promising. But just for starters, who wants to venture a count on how many sub-millimeter sized scales covered a T. rex? What is the morphology of these scales? Any sort of repeating pattern? Architecture?

Are retro '90s Tyrannosaurs making a comeback? is a recent post by Paleo-King (Nima) on deviantart. While the general thrust of his piece is useful he makes a claim in the comments section that the various tyrannosaurid scale impressions are exactly the same as the well documented hadrosaur scales/mummifications. I do have to take issue with this comparison.

1) Extent of preservation. In hadrosaurids we have full on mummies that give us real life confident appraisals of where and how far scales occurred. So far in tryannosaurids we just have bits and pieces. Together these pieces suggest that "scaly" type integument is our most parsimonious appraisal for most of the body, if not all of it. But keep in mind that we as of yet don't have proof of "scaly" integument on the face and those persistent rumors of non-scaly neck displays in Tarbosaurus. Remember both crocs and birds have dispensed with scales on the face. Why? I'm not sure. It is interesting that both crocs and birds both have highly sensitive, tactile faces as well.

2) Size of scale and variety. While some hadrosaurs show scales on the millimeter range such as the Osborn "Trachodon Mummy" which are 1-5 mm and are described as "pavement scales" these patches of small scale are interspersed with regular patches of "feature scales" which are much larger at 5-10 mm.  What we see in terms of scale variety in tyrannosaurids so far is quite limited to very small "basement" type scales of a size smaller than in hadrosaurs. Hadrosaurs both at a distance and up close would have appeared much more textured than tyrannosaurids based on what we know so far. Unless you have some super X-men levels of visual acuity tyrant lizards would have looked basically nekkid.

3) Architecture. Nima points to an obvious architecture in the scales of tyrannosaurids. I have to admit that I can't see it. Carnotaurus shows architecture in the regularity of larger 4-5 cm tubercles arising every 10 cm or so from a more "basement" size scale of 5 mm tubercles. Sauropod and hadrosaur scales show a more obviously repeating scale architecture than tyrannosaurid tubercles. What I see in the tyranosaurid tubercles is something of a much more random, haphazard pattern. Apart from a size threshold of about 1 mm for the tubercles I can't discern any consistency in size; some appear more than twice as big as others and shape - apart from being generally polygonal there is a wide variety of shapes. Some of the tubercles appear rounder; others ovoid; some taper to a point; some wrap around others; and some almost to appear to bud off into other tubercles. This is a far cry from the more standardized scale pattern of hadrosaurs, which are often in repeated hexagonal patterns. Additionally given the 30 square cm patch of ilium scales we can be pretty confident that there was no larger patches of feature scales or repeating rows of larger keeled scales/osteoderms as in Carnotaurus, titanosaurs etc etc.

*Update. looks like a spoke too hastily, Nick Fonsesca says that Tarbosaurus has some feature scales form the supplementary info and then there is this from the paper:


Although I could not see the feature scales pictured in the supplementary there is indeed some evidence for a more orderly pattern of tubercles on some tyrannosaurid specimens, although not from the Wyrex material. It is of note that these feature scales are from the abdomen. Can they in fact reflect a more basal state retained? (i.e. never became completely feathered). Things are always aflux!!


So are 90's tyrannosaurs making a comeback? Sort of, I would say, but not exactly. The lack of discernible rows of feature scales or keeled scales is an obvious departure from GSP tyrannosaurids or any sort of organized row of larger scales so prominent in 90's style GSp tyrannosaurids.

And here I have to admit a weakness of not trusting my own gut and capitulating to the whole shaggy T. rex visage that has come into vogue in recent years. I blame Saurian. No, just kidding, I jest just a bit. Some have construed some of my posts as an attack on Saurian game design or that saurian should be changed or whatever. I can't disagree more. In fact I feel a bit sorry for the development team at Saurian, they must get pestered by young dino obsessives all the time. Just leave 'em alone at this point!! If Saurian is wrong fundamentally in some ways I think - at this point - these potential errors should be preserved for posterity. It's always interesting and iluminating to look back on paleoart to see how thought and ideas have changed. Saurian can be a great time capsule for what the general thought was of this period.

I do feel a bit of edification in getting back to my gut feeling for my latest tyrannosaurid art, in which I went with mainly nekkid skinned tyrant lizards with some manes and petty-coats of filaments. Proud to say this was completed before the new data came in. Boo - ya!! No need for revisions here, folks! Who says intuition, gut feelings, and following your muse have no place in science!! First published March 23, 2017 Gaslighting the Dinosaur: Just How Weird Can Dinosaurs Get?

Revelations by Duane Nash

Another argument that I would like to weigh in on is why Yutyrannus would go fully feathered while similarly sized northern tyrants like Albertosaurus went nekkid in a climate that was presumably not too different in temperature. Not to discount some of the other suggestions but merely augment, let's keep in mind that Yutyrannus was a normal slab chested theropod. Tyrannosaurids came wit da thikkness, they were barrel chested beefcakes, much more better heat retention in the torso. Big bois. Throw in some nice counter current heat exchange for the extremities, maybe a bit of a fat layer too, and you have a pretty good heat retaining system - much better than slimmer, earlier theropods at least. Perhaps a seasonal coat was a thing in northern variants, perhaps the young sported downy coat.

Back to the topic, again, my argument is not one of denying the overall message - that tyrannosaurids had a mainly "scaly" integument - but that the tyrannosaurid "scale" in both size, shape, architecture and pattern is quite distinct from those qualities of scales discerned in Carnotaurus, sauropods, and hadrosaurids. The differences in tyrannosaurid scales between these, presumably more basal integumentary patterns, very well might indicate secondarily derived "scale" patterns. In short that tyrannosaurids - like modern birds - had to reinvent the scale from a mainly feathered ancestral state.

This of course is not a novel concept, indeed the authors of the paper (Bell et al. 2017) seem to lean this way themselves. What I want to offer is that this T. rex "scale" - as suggested by the patterns discerned already - is best approximated by looking not at the exposed skin states of crocodilians with their regularly repeating, consistent, large, and architecturally sound scale designs. No the exposed skin state of tyrannosaurids is best approximated by comparison with the other archosaurs (i.e. birds) that have had to "reinvent" scales after losing them initially upon evolving a completely feathered countenance. When we look at both the small turberculate "scales" on the legs of birds and… wait for it... the minute "scaly" pattens discerned on some examples of carunculate skin of birds we can imagine a sort of novel tyrannosaurid integument that splits the difference between bird leg scales and carunculate skin. This novel skin morphology would be a lot more thicker and durable than carunculate skin but offer adequate blood flow for thermoregulatory and color flushes. Such a novel skin type combining elements of carunculate skin and bird leg tubercles would be consistent with the preposterously small tubercles of tyrannosaurids, their haphazard shapes, and offer immediate benefits for thermoregulatory and display functions.

Carunculate skin answers the question of why - when compared to other scaled dinosaurs - T. rex scales are diminuitive, non-architectural, no consistent shape, sort of globular, and devoid of rows, repeating patterns etc etc.

Oh yeah, and before you go "there goes Duane and his caruncles again" know that others have been pointing out this similarity between tyrannosaurid "scales" and carunculate skin as well…

credit Marco Muscioni

If you go back and review the T. rex skin impressions there are some very bumpy, textures reminiscent of carunculate skin. You will also notice the skin infoldings and the small size of the tubercles in carunculate skin is consistent with the unparalleled small size of T. rex"scales" and the skin creases shown in preservation.

Bell, 2017

You can take a wild guess how often the term caruncle comes up in the Bell paper (or the Carr paper for that matter). A big fat nada, zero, zilch, ninguno. I guess we don't have to talk about carunculate skin if we pretend it does not exist. Robert Bakker, I'm disappointed in you, especially since you have worked a lot with Luis Rey who gave us one of our first caruncle ridden theropods. Robert Bakker, you should read more antediluvian salad. Yes, the hate, disdain, disapproval, and ignorance for carunculate skin knows no bounds both from professionals and lay enthusiasts. And so perpetuates the false dichotomy of feather vs. scale, leaving out the retarded stepchild of carunculate skin… always the bridesmaid, never the bride.

Ye shall know it when ye sees it…

What was once scaled becomes feathered then becomes something new…

A quasi scaled, nekkid skinned, caruncled beast. Not completely serpent or fowl.

Ladies and gentlemen this is what modern theropods (i.e. birds) do when they get rid of their feathers. If we assume feathers and scales are more than a little competitive developmentally, when feathers diminish a nekkid skin is left. In order to toughen up this nekkid skin faux scales can be reinvented as they have been on the legs of modern birds. In other areas, especially of the head, nape, and neck a more motley growth pattern of various carunculate skin devices can commence. Carunculate skin can also have a superficially scaly facade. In large and gigantic theropods that mostly or completely lost feathers carunculate skin and tuberculate scales analogous to modern bird leg scales can potentially combine and envelope the torso as well, creating new motley and outlandish textures.

The dark little secret of carunculate skin is that it is found in not just one modern bird family, but many. We are left to consider two possibilities. Carunculate skin is basal to birds and quite possibly goes way back into theropods or: that it evolved independently in many different bird lineages. Both scenarios bode well for such epidermal growth to be quite common and expected in theropods that dispensed with feathers or possibly even some dinosaurs that never evolved feathers?!? (I'm looking at you Edmontosaurus)

Dang Tao Chicken "Do these caruncles make my feet look fat?"

And finally I leave you with a soft tissue preservation of another extinct giant theropod, a Moa. Do you detect some integumentary patterns that might in fact be construed as "scales"?



And finally, for the haters, social media harassers, stalkers, chastisers, discounters, "don't listen to Duane he is not teh true paleontologist", and all around perpetrators. You inspire me. Keep it coming. I stole the show with Spinosaurus and I'm doing it again right here. This C-walk is for you.
CARUNCLES BIATCH!! Up in Your Grill!!




Refs

• Bell, P. R., Campione, N. E., Persons, W. S., Currie, P. J., Larson, P. L., Tanke, D. H., & Bakker, R. T. (2017). Tyrannosauroid integument reveals conflicting patterns of gigantism and feather evolution. Biology Letters, 13(6), 20170092.
• Bell, P.R. A Review of Hadrosaur Skin Impressions. Hadrosaurs. Indiana University Press 2014

• Carr, T. D., Varricchio, D. J., Sedlmayr, J. C., Roberts, E. M., & Moore, J. R. (2017). A new tyrannosaur with evidence for anagenesis and crocodile-like facial sensory system. Scientific Reports, 7.
• Cau, Andrea. Those Scales Are Scales? Theropoda. June 7, 2017 webpage
• Nima (Paleo-King) Are retro 90's Tyrannosaurs making a comeback? 2017 webpage
• Witton, Mark. Revenge of the Scaly Tyrannosaurus. Mark-Witton.blogspot June 16, 2017. webpage

"A Long habit of not thinking a thing wrong, gives it a superficial appearance of being right, and raises at first a formidable outcry in defense of custom". Thomas Paine

Ahhh those theropod forearms. They are a bit of an enigma, no? As bipedal primates descended from a brachiating pedigree of ape we have an intuitive awareness of our ability and utility to reach out and grab things.  Predatory theropods, despite being bipedal and equipped with arms and fingers like us, were a bit more constrained in their forelimb movements. The neck and head would be the first to contact with prey, the arms and claws being substantially rearward. Furthermore, the range of forearm extension and wrist movement was severely limited. Essentially the forearm and wrist acted as one single unit with the wrist unable to rotate and the radius and ulna locked together unable to rotate as well. The shoulder was likewise constrained to a relatively smal range of motion. Would it not have benefited predatory theropods to have freed up their forearms, wrists, and shoulders for a wider range of motion to assist in prey capture and manipulation? So that they could "reach out and grab stuff" like we do?

Suchomimus credit Duane Nash

Interestingly, there appears to have been at least one instance of theropods increasing both wrist and shoulder mobility and thus evolving the ability to "reach out and grab stuff" (Zanno et al., 2006). From wikipedia:"Within Therizinosauridae, broad changes to both the structure of the forelimb, pelvic, and pectoral girdles likely corresponded to changes in the lifestyle of the animals. The forelimb has undergone a drastic increase in robustness, the flexibility of the wrist has increased, and the presumed reach of the animal is believed to have lengthened. Moreover, the pectoral girdle has been modified to further augment upright reach, however the grasping ability of the animals is thought to have decreased. As with the modifications to the head, these adaptations are thought to have assisted with an herbivorous lifestyle, as they may have increased the ability to harvest and collect vegetation.^[3]" The obvious implication is that when the need arose to "reach out and grab things" the commensurate forelimb adaptations did arise - except that they did not arise in a predatory theropod but a likely herbivorous/omnivorous one!! Maybe the predatory theropod forelimb arsenal was not functionally adapted for "reaching and grabbing things" but served a separate purpose? Perhaps we are not satisfied with theropod forelimbs - that they are a bit enigmatic - because we are assuming the wrong job for them?



There is currently a strong notion that whatever the forelimbs were doing - they were of secondary importance to what the head was doing in predatory theropods. And that if the hands were involved in prey capture they stabilized and held prey for the benefit of the head to deliver the dispatch. This notion is actually impractical for several reasons. Theropods neck musculature studies on Allosaurus indicate a design optimized to strike ventro-flexively (Snively et al, 2013). In other words they struck down and out away from the body. They were not optimized to strike back towards the body as would be expected if they bit into prey held in place by the arms. Furthermore the sheer implausibility of such a design is patently obvious when one tries to align the kinematics of such an action in the theropods with especially reduced forearms and short powerful necks such as tyrannosaurids and carcharodontosaurids.  Can anyone point me to one convincing depiction of short armed theropods holding prey with their arms as the bead bites into it?  It is also a bit of a myth that grasping hands are even necessary for the killing and dispatching of reluctant prey items by the mouth. Even a cursorary overview of both terrestrial and aquatic predators reveals that this is not the case - that the skull can be both a grasping and killing instrument - no hands need be involved.

Crylophosaurus credit Duane Nash

For this piece I am going to approach these "limitations" in wrist/arm/shoulder mobility from a different perspective. That these limitations were not at all limitations - they were in fact adaptive benefits. And that these benefits were not actually in place to assist in the capture of prey i.e. "the reaching out and grasping of prey", that was the job of the head. The forearms and wrists of predatory theropods were in fact so severely limited because of two, not mutually, exclusive reasons; 1)  many theropods would have dispatched prey with hand claws after the initial grasp by the jaws and 2) all predatory theropods - with notable exception of abelisaurids - would have used their forearms to transport food parcels to localized feeding locations and perhaps mates/offspring.

In other words it proves useful in flipping the equation: " the arms held prey for the head to dispatch" into " the head grabbed prey for the arms to dispatch" in order to understand the forearm use in a great many predatory theropods.

credit Brian Eng.

An important distinction that will color these arguments arose from an observation that Andrea Cau brought up to me in discussions on abelisaurids, theropods, and forearms. That there is a roughly inverse relationship between the power and bite of the head and the bulk and importance of the forearm in predatory endeavors. That is, for the theropods with weaker, slashing, and more modest skulls and teeth,  forearm strength and killing capacity are enhanced: spinosaurids, allosaurids, neovenatosaurids, megaraptors, basal tyrannosauroids, among others . Alternatively, where head power is enhanced arm strength and killing capacity is diminished: carcharodontosaurids, ceratosaurids, tyrannosaurids, abelisaurids. Now certainly this is not a hard and fast distinction, there were shades of grey, but I think it is a useful way to parcel out the discussion. No I am not saying that Suchomimus never killed with its mouth, nor am I saying that T. rex never killed anything in its hand claws. But they did invest in different arsenals and this should matter.
*Note that only in abelisaurids do we see the arms mutated into vestigial structures. This is an important distinction because even in theropods with reduced forearms they were not vestigial but offered an important functional usage in the transport and relocation of food resources. Dromaeosaurid forearm use will be discussed in a future piece.

In order to disabuse ourselves of the  notion of theropod forearms as tools for "reaching out and grabbing" or "holding onto prey for head dispatch" I want to revisit a term often used in the discussion of predatory theropod hand claws: meathooks. The term is a useful one, not only because it alludes to a human contrivance, but expresses quite succinctly the use of these forearms with due credit to notions of form and function having applicability not only in natural systems but culturally mediated systems of butchery. In both situations form follows function.

Megaraptor hand. author raffaeli serge CC2.0

Enough with all these academic pedantry I want to give you, the reader, an immersive feeling on what it was like to be young sauropod skewered alive on the Megaraptor meathook claws.





Ladies and gentlemen it is disturbing because the Mesozoic was disturbing - a real horror show. Now keep in mind the meathook claws of theropods, combined with a rather inflexible, strong, and stoutly built arm, work in conjunction to lock a food item in place. Such food items are pinned by either the opposing arm and claws or are wedged in against the torso. It is the meathook morphology of the claw combined with the limited range of motion of the arm and wrist that actually make escape from such a contraption very remote. In other words, the exact flaws that we have felt for so long are built into the system actually in this view are benefits. The prey can't squirm out of the arms due to the inherent inflexibility of the arms!!

credit Brian Engh used w/permission

Brian Engh (Don't Mess With Dinosaurs) did this evocative mural depicting speculative dinosaurs of the early Jurassic New Mexico sand-stone. Brian made the rather atypical depiction of the putative top predatory holding a coelophysid in its claws. Also check out Brian Engh and other paleo goodies on July 13th 2017 at nerd night in L.A. if possible. I will try and make it too!!



There have been some detailed studies on large predatory forelimbs. One of the most interesting and little heralded studies is by Senter & Robins 2005. What I want to draw attention to in this abstract is; the extreme flexibility of the manus - the fingers can hyperextend; the permanently locked and bent elbow, unable to straighten; the notion of struggling prey further impaling itself on digit 1; and the noted difference between coelurosaur finger flexibility (they were doing different stuff) and other theropods .


What this study gets really right I believe is where they say "Acrocanthosaurus could manually grasp prey that was beneath its chest, towards which it may have used its mouth to move prey. Struggling prey would have impaled itself further upon the permanently and strongly flexed first ungual."Perfect, they really nail it here because they are the first - that I know of - to really decouple the forearms from the head as killing instruments in their own right. That is, it is not the claws holding the prey for the head to dispatch it is the head moving prey towards the claws for dispatch!! And this notion of the head deliberately moving prey items towards the killing hand claws does mesh well with the idea of sub equal sized prey items (i.e. loads of baby dinos) forming a heavy part of the diet of these animals. So while I am not the first to make this distinction - that the hands were killing implements independent of the head - I see no reason why this method can not be extended out to a whole range of other meathook handed theropods. Again, I'm not the first to advance this idea but I still maintain it has not garnered widespread exposure and knowledge.

The almost preternatural flexibility of some theropod fingers is something that does not get enough press. Once you look at the range of extension one has to wonder, why? The answer I would suggest is that the fingers took a lot of abuse from prey items squirming while engaged in the meathook bear hug. In order for the fingers to remain hooked in such flexibility would be paramount. No matter how hard and strongly the prey item squirmed the fingers would just flex and move to keep the hapless victim ensnared. Furthermore the basic function of an animal lifted off the ground and struggling against gravity would dictate that the claws dug in deeper to the animals; body cavities penetrated; lungs punctured; ribs cracking; viscera perforated; tendons gouged; and spinal integrity compromised. Abso-fucking-lutley brutal.

It is an ingenious solution: the fingers can bend and extend all over the place to absorb the struggles of the prey item, alternatively the extremely inflexible wrist, forearm, and shoulder maintain a rigid "meathook bear hug". Diabolical.

Probably the best visual I can find for the crazy hyper extendable meathook claws of some theropods is this visual from the recent study on Australovenator forelimb motion.

"I'll Show You the World"Australovenator credit Duane Nash

The megaraptoridae took this forearm dominance to the hilt, they also appear to show a bit more forward mobility in the shoulder joint perhaps even allowing food clenched in the hands to be brought up to the face - an unsettling manner of eating due to the similarity to our own feeding style.

credit Matt A. White, Phil R. Bell, Alex G. Cook, David G. Barnes, Travis R. Tischler,Brant J. Bassam,David A. Elliott

Also of note is that by allowing the arms to engage in the killing activity the head - and most importantly the eyes - are safeguarded from retaliatory jabs of struggling prey. Many a prey item probably met their end after the initial grasp of the head in the clutches of the meathook bear hug. Trenchant hand claws - especially massive ungual one - dealing the death blow via grievous bodily insults much quickly and safely than injury incurred by the slashing teeth.

Of course I would be remiss to not give a mention to the several studies documenting abundant - and often extreme - forearm pathologies in predatory theropods (Senter & Juengst, 2016) in which a Dilophosaurus got absolutely wrecked, like freaking Monty Python style.

from Senter & Juengst. credit L. Walters (LWPaleoArt)

Senter & Juengst do a nice summary of documented forearm pathologies in theropods in the introduction - therefore saving me a load of work so I will put that here:

Some comments - a lot of mention of T. rex here. That might be a bit surprising considering T. rex should fall more into the "kill with mouth" gestalt. But there might be some reasons. As I will discuss later specific circumstances may have necessitated live prey being put in the arms of T. rex and other mouth dominant killers; the public, and researchers, like to obsess on T. rex so it might just be more looked over; multiple specimens; pathological features may often be omitted or overlooked in descriptions. Overlooked and omitted pathologies is interesting and Senter & Juengst go into some detail in these regards:

I should also give a mention to the work of Rothschild et al, 2001 that did some work on stress fractures and tendon avulsions in theropods as indicative of an active predatory lifestyle. I don't have the original work but it is heavily cited in the wikipedia articles on Ceratosaurus and Allosaurus both of which evince evidence of forearm and manus pathologies. Indeed the well documented trauma that Allosaurus sustained might be indicative of a willingness to sink its meathooks into prey substantially larger than itself!!

Earlier in this discussion I alluded to some of the reasons why a T. rex or other "mouth killing" theropods would have put a live or still struggling prey item in the grasp of its forearms. I also want to suggest some reasons why we should be optimistic about the utilitarian benefits of hauling parcels of food around in the arms (except for abelisaurids of course wink, wink). Let's remain mindful that as reduced as tyrannosaurid arms were, they were not vestigial. They were actually pretty damn powerful, conservative estimates give T. rex about 430 lbs on the bicep curl - a feat no human, not even pro-body builders can ever hope to achieve.

Removal of food from a highly competitive/dangerous arena to a more secure locale. Modern predators do it all the time. Hyenas haul off bits or whole carcasses. Raptors will take their prey off the ground to a safer location to eat. Leopards haul their kills up into trees. Carcasses can attract a lot of undue attention and if you have a way to move your larder to a more secure locale all the better for you.

*Note that, unlike quadrupedal predators that have to carry food in their mouth, theropods carrying food in their hands can still lash out and defend against would be usurpers with their mouth.



Transport of food to a mate and/or offspring. It is weird to think of such prosocial behavior in these animals but not without merit. Especially in light of the recent incubation lengths given for some dinosaurs - if such lengths were emblematic of theropods - then I think the discussion swings more and more into this realm.

Southern Ground Hornbill feeding mate. credit Steve Upton

Maximize exploitation of an abundant ephemeral food source. This is one of the funnest ones for speculative and humorous depictions. A bivouac of baby dinosaurs, a trapped pool of lungfish, a beach full of nesting/hatching sea turtles. Every once in a while predators get a gargantuan smorgasbord of easily acquired and abundant food stuffs and then it is gone. Theropods I would put forth as champions at taking advantage of these windfalls. First swallow as many as you can, then have each arm carry one, and finally cram as many into your maw as possible.

Greedy Daspleto credit Duane Nash

Atlantic Puffin w/sand eels credit Paul Mcllory CC2.0

So to review some of the main points:

- Predatory theropod forearm use has been stymied by our own intuitive understanding of having flexible, grasping forearms. We expect that theropods should have the same use of forearms in "reaching out and grabbing stuff" as we do, so that when we see they are limited in this regard it is thought of as an imperfect, problematic system.

- A study on the forearms of Acrocanthosaurus is one of the first mentions of theropod forearms being decoupled from the head as a killing mechanism in their own right. Forearm killing dominance has also been suggested for megaraptorids but can be extended out towards other theropods to varying degrees.

- There is a general pattern showcasing a trend from more mouth dominant predators to more arm dominant predators. Towards the extreme of forearm dominant predators would be spinosaurids and megaraptorids, towards the mouth dominant extreme would be tyrannosaurids and carcharodontosaurids.

- A meathook type claw morphology combined with a rigid arm anatomy would allow predatory theropods to not only kill but to carry prey/remains manually, useful for several very practical and not mutually exclusive reasons i.e. relocation of carcass, feeding of mates/offspring, hoarding of ephemeral rich food source.

- Forearm pathology in theropods is consistent with a heavy dependence on forearms in acts of predation.





References

Rothschild, B., Tanke, D. H., and Ford, T. L., 2001, Theropod stress fractures and tendon avulsions as a clue to activity: In: Mesozoic Vertebrate Life, edited by Tanke, D. H., and Carpenter, K., Indiana University Press, p. 331-336.

Senter, Phil; Robins, James H. (2005). "Range of motion in the forelimb of the theropod dinosaur Acrocanthosaurus atokensis, and implications for predatory behaviour". Journal of Zoology. 266 (3): 307–318.doi:10.1017/S0952836905006989

1. Snively, E., Cotton, J. R., Ridgely, R. & Witmer, L. M. Multibody dynamics model of head and neck function in Allosaurus (Dinosauria, Theropoda), Palaeontol. Elect. 16(2), 11A 29p (2013).
   
   

White MA, Bell PR, Cook AG, Barnes DG, Tischler TR, Bassam BJ, et al. (2015) Forearm Range of Motion in Australovenator wintonensis (Theropoda, Megaraptoridae). PLoS ONE 10(9): e0137709. https://doi.org/10.1371/journal.pone.0137709

Zanno, Lindsay E. (2006-01-01). "The Pectoral Girdle and Forelimb of the Primitive Therizinosauroid Falcarius utahensis (Theropoda, Maniraptora): Analyzing Evolutionary Trends within Therizinosauroidea". Journal of Vertebrate Paleontology. 26 (3): 636–650. JSTOR 4524610. doi:10.1671/0272-4634(2006)26[636:tpgafo]2.0.co;2.

Utahraptor by Duane Nash

You know its that time again folks, more dromie madness. Antediluvian salad has a bit of a controversial history with these most pernicious of stem birds. You can be sure that part is not going to change, the controversial bit, that is.

For a brief review:

Making Dromaeosaurids Nasty Again Part I: Wing Pummeling Abuse In which I discuss the current state of affairs with regards to killing claw use and hypothesize that prey restraint by the foot "killing claw" coupled with clawed wing pummeling may have been utilized. As you will see in this post I no longer consider such a method of restraint and killing as preeminent. That is - shades of grey here folks - I don't think that both the raptor prey restraint model and the wing pummeling hypothesis were chief strategies for prey dispatch in most dromies. Could both style of attack been used on occasion by some dromies? Yes, but as I will explain both theses methods become vanishingly tenable tactics especially at larger sizes (hello Utahraptor).

Making Dromaeosaurids Nasty Again Part II: No Shame in the Scavenging Game I start building the case for many dromies as excellent facultative scavengers. Not only is there fairly unequivocal fossil evidence for it, the size range of dromies slots in nicely to an ecological "sweet spot" where terrestrial scavenging is most utilitarian. Also Dakotaraptor as a large, cursorial carcass bully.

Making Dromaeosaurids Nasty Again Part III: Life Appearance - Dapper of Deranged Probably - at least based on the comments - the most controversial of the series. I would say it has held up nicely, especially in light of the compelling evidence that tyrant lizards "de-feathered" significantly. "Wut you mean that dromies did not all look like carbon copies of each other in the 100 million years of evolution they underwent? Get out!" Look folks it's not even that wild of a suggestion, in fact pretty common sense actually. Almost boringly so.

Making Dromaeosaurids Nasty Again Part IV: New Hypotheses on Dromaeosaurid Feeding Technique & Role of Tail in Movement For me this was the most fun and interesting post in the series as it combines unusual oral feeding styles with a novel idea on dromaeosaur locomotive strategy.

I introduced, for lack of a better term, the "woodpecker hypothesis" of dromie carcass feeding technique. In this scenario quick twitch muscles generated in the body vibrate culminating energy at the tooth tip where strange apically hooked serrations on the teeth allow the tooth to literally dig into carcasses. Several examples of worn dromie teeth and inexplicable bone damage on Tenontosaurus can be potentially explained by this hypothetical feeding style.

I then discussed how the pattern of caudal rods in dromie tails could potentially work as an elastic recoil allowing energy efficient, long distance travel, useful for reaching ephemeral food sources and carcasses. I make the comparison to wolverines which, despite their short legs, are remarkable and unstoppable moderate paced long distance cursors. I augmented this suggestion with a review of dromie ichnological traces - the footprint record shows that these animals had not only large foot and toe pads but that they most likely cruised at a fairly high pace.

Here I have to admit to having a bit of mud on face here folks as a frequent theme of my "Making Dromaeosaurids Nasty Again" series was a diminishing of the  role of the killing claw in predatory endeavors, highlighting wing pummeling and biting as more preeminent tactics for dispatch while the feet grappled and held prey. So I'm gonna eat some crow here in coming around full circle in my opinion on that most famed of claws - foot ungual #2, aka the "killing claw" I now believe really was a killing claw just not in the way that we have been interpreting it.

Full disclosure, the genesis of this idea is not mine own although after mulling it over and especially with the Utahraptor reveals I think it should be the leading hypothesis. What I want to document is the transmutations and permutations an evolving hypothesis should go through and in this case I believe did go. New ideas rarely come fully realized and perfected into the world. They need refinement. In the case of this idea which I will dub the "pierced from within" hypothesis the first semblance of it to my knowledge was put forth by Kenneth Carpenter. However the man who improved - but didn't perfect it - is.... wait for it... a certain chap named John Jackson.

Upon writing that name I can almost hear the sound of mouses clicking on the close window for this page. But bear with me. To those uninitiated John Jackson is best known as a chief proponent of the "Birds Came First" BCF idea of theropod/dinosaur evolution. He also has a reputation online for a particularly prickly correspondence to put it mildly. You can do your own internet sleuthing on John Jackson if you are new to this idea or the man - here is a good place to start (read comments). But let me unequivocally state I don't subscribe to the BCF idea of dinosaur/bird evolution (ironically someone brought up a retooled version of this in the comments from my last post). I'll admit it had a certain intuitive appeal to it in the 90's and was fresh and original - but the evidence has not borne it out. John got in contact with me after reading several of my dromaeosaurid posts and we had a brief series of email exchanges (we don't correspond anymore, you can take a wild guess why). I try to keep an open mind on things and gave his self published book - The Secret Dinobird Story (free on kindle) - a read. The book is a bit of a slog to get through, and I told John this. I came away still unconvinced about BCF and this post is not about this topic nor do I want to discuss BCF in the comments. But nestled within John's writings on the philosophy of science, unorthodox family trees, "arboreal stem dinos",  and complete eschewing of cladistics ( I have problems with cladistics too but don't think we should discount them), is hidden what I believe is an important and unrecognized broad stroke analysis of how dromaeosaurids actually used the famed killing claw. I can only assume that people who know of John or have perused his book glossed over his bit on the killing claw. It is in my opinion an unpolished gem and should see the light of day. With whatever light I can give this idea I will shine upon it.

The killing claw is not a tool used as a crampon to hang onto the sides of other dinosaurs, nor is it a tool used to pin and hold subequal sized prey items ala the raptor prey restraint hypothesis. It is a tool used with almost surgical precision to slice into and penetrate a prey item in select spots. Such a claw is not optimized to scythe style cut long gashes in the tough hides of prey but instead cuts a single entry hole into prey. A laterally compressed horny sheath with a cutting edge can, after the initial entry into said prey item, now repeatedly plunge into, explore, and cut into the underlying soft tissues. Such trauma will perforate vessels, arteries, lungs, and viscera. Although from the outside trauma will be evinced by a simple entry hole the interior damage will be substantial and often times fatal. Arms and/or jaws assist in stabilizing struggling prey in such a manner to allow entry of killing claws into prey for fatal dispatch. Such a tool is every bit the theropod equivalent to saber - toothed predators and allowed dromaeosaurids an ability to punch well above their weight class in predatory endeavors.




John called it the toe and tail, grab and stab method. He believed that the caudal tendons of the tail worked somehow to help "kick into" the prey item deeper but the (unpublished) revelation that Utahraptor dispensed with these caudal rods causes me to distance myself from that aspect of the idea. As I have discussed before I think that those caudal rods assisted in long range, mid paced efficient travel and it makes sense that Utahraptor dispensed with them as it likely was the >the most predatory< and least adapted to facultative scavenging among known dromaeosaurids due to its size, extreme robusticity, and heavy investment in weaponry. Furthermore the loss of such rods helped the tail in flexibility as it could both deliver and take a beating.

To better understand and see how we got to where we are today and where I think we will be going a quick review of the pertinent thought on the use of the killing claw in these animals dominated by two papers Manning et. al. (2005) and Fowler et. al. (2011) with necessary criticisms.

Not a Slicing Weapon But a Puncture and Pierce Weapon

The main death knell to the "ride the back of iguanodonts and slash at the sides with toe claws" hypothesis of dromaeosaurid killing technique came in the form of a mechanized Deinonychus leg built and utilized by the team of Manning et. al. back in 2005. They found that not only was the hole created by the claw very superficial but slicing through skin in order to create long gashes would be inefficient due to the skin tending to bunch up prevent said slicing. However, as John points out in his book such an analysis is lacking in terms of puncture depth because the experiment did not take into account the compliant nature of body tissue and that the claw can be pressed into the prey animal deeper via body weight and/or muscular force. Long story short the experimenters did not think with enough murderous intention. They did not think like prison inmates trying to achieve fatal blows with self made prison shanks. When body tissue is not put under pressure all the soft, delicate and gushy stuff is relatively safe due to the layer of integument, muscle, adipose tissue etc etc. But press into this tissue - with a prison shank or a dromie killing claw - and the margin of safety diminishes.  Stick the knife in and twist.

Critical reception to Manning et. al. is not however new and not isolated to John Jackson. Both Dave Hone (archosaur musings) and Mike Taylor (SV-POW) express similar notions in this interesting back and forth from Ask a Biologist. Many of the points they raise, especially with regards to the problems of "puncture and hold" and the likely inference of a sharp cutting edge to the killing claw can be extended out to criticisms of the now dominant RPR model of Fowler et. al. (2011).

Not a Holding Claw But a Cutting Claw

After Manning et. al. prescribed their case against killing claws slicing meter long gashed into the side of prey items the next big chapter in this saga came in a paper by Fowler et. al. (2011) that brought us the now dominant hypothesis of the Raptor Prey Restraint model (RPR) that proposes a certain commonality with modern birds of prey that grab prey with foot talons, flap with wings to maintain dominant position, and eat/dispatch with the head. As I have said in the past there is much to like here and it is not surprising that many have become somewhat smitten with the RPR restraint model. But as the authors themselves concede the grasping ability of dromaeosaurids is not >as mechanically strong< as modern raptorial birds of prey. Add to this; dromaosaurids do not have truly opposable halluxes like raptors - they can't do a good strong vice grip; longer legs decrease mechanical advantage further diminishing the strength of the grip; and dromaeosaurids had big foot and toe pads which would diminish the tightness of the grip. Because of the big foot and toe pads that dromies had getting a firm grasp becomes problematic, sort of like trying to grasp things with your own toes to a lesser extent. Not impossible for us and not impossible for dromies, but issues arise suggesting a less than optimal performance.

But the final nail in the coffin for the dominance of the RPR model lies in the shape of the claw itself. It is not circular in cross section as we see in extant raptorial birds of prey but is laterally compressed like a knife is. It is just begging us to infer a sharpened cutting edges for the keratin sheath.

credit Robert DePalma  killing claw Utahraptor (L) Dakotaraptor (R)

The Diminishing Utility of Stability Flapping in Larger Dromaeosaurids

Not to dismiss the RPR restraint model in its totality - I can picture small game and smallish dromies (troodontids especially) - pinning small with their #2 claw and even flapping with their arm wings a bit to maintain top dominance. However in larger and larger dromies this tactic becomes vanishingly feasible and outright ludicrous in Utahraptor sized dromies. It is, in essence the bio-functional equivalent to a fat guy in a little coat, two things combined that don't make sense.



Think about it, Utahraptor was big and robust, like polar bear sized. It was no light weight. The notion that arm wings on such an animal - if they even existed and were not functionally reduced - could generate enough power and lift to achieve any semblance of control and lift necessary for stability flapping should be tossed in the scrap heap of bad ideas. Again, not sail gliding Stegosaurus bad, and it is entirely possible that some small dromies/microraptorines/troodontids engaged in some stability flapping in choice circumstances. But pretty indefensible when we imagine what stability flapping really means - that dominant vertical position is maintained via wing-arm strength flapping strong enough to control not just one body but two struggling bodies - then the utility of stability flapping becomes vanishingly small in dromaeosaurids much larger than - ball parking here - turkey sized? I definitely would say stability flapping is pretty nonsensical in full grown Deinonychus and maybe even Velociraptor...

What Does the Evidence Actually Show?

Which is exactly what the fossil record tells us. Remember we do have a certain Velociraptor locked in mortal combat with a Protoceratops.

CC2.0 credit Yuya Tamai Protoceratops & Velociraptor fighting dinosaurs

We shouldn't feel compelled to explain such a situation as abnormal or a very rare occurrence. It was common enough to enter the fossil record after all.  And it is doing exactly what should be expected in the scenario John Jackson laid out in his book. Velociraptor is not hitching a ride on the side of the Protoceratops, not is it stability flapping or grasping the animal with all of its foot claw in some weird type of proto-raptor foot grasp. The head of the Velociraptor is poised to strike but may not be all that important for the killing. The arms and hand claws are very important in the predatory endeavor as they seek to restrain and stabilize the prey animal for ultimate dispatch by the killing claws. Given their increased range of motion and length compared to other theropods they performed a different role in predatory actions. They grappled with prey and helped to hold and stabilize prey which in turn allowed the killing claw to strike with better precision and accuracy. This is directly analogous to the manner in which large felids will grapple with prey using their forelimbs and secure the prey for dispatch via throat bite or nasal blockage. Finally the killing claws are doing exactly what they should be doing... killing!! They appear to be literally gouging into the neck region!! Poor Protoceratops!!

We actually had an earlier iteration of this idea laid out to us by Kenneth Carpenter in a review paper titled Evidence of Predatory Behavior by Carnivorous Dinosaurs (GAIA, 1998). Carpenter raises concerns with the idea of sickle clawed theropods disemboweling prey items but in his analysis of the fighting dinosaurs he makes specific mention of the likely killing style as evinced by this most remarkable of preserved interactions:


Carpenter also provides several diagrams of sickle claws with specific mention of a likely sharp cutting edge. Unfortunately Carpenter strangely backs off of the cutting edge aspect of the claw likening it to being "less sharp than a dull knife". Perhaps he was being a tad overly conservative, in any case Carpenter reasons that sickle clawed dinosaurs had  such blunt claws because: "although we don't know how sharp the keratin sheath of a dromaeosaurid claw was, it was probably less sharp than a dull knife because there was no way for a dromaeosaur to hone an edge."


Let's reason this out. Dromaeosaurs revamped their entire hindlimb morphology, literally raising digit two off the ground in walking posture. And we are to presume all of these sweeping morphological changes were done merely to create a claw with a sharpness less than a dull knife?!? Come on now.

If we merely make the defensible assumption that the keratin sheath grew constantly then we can safely assume that the animal had to hone it down through use on prey items or why not simply hone its claw like a felid does? What's going to stop it?

So when we add it all together we see this first iteration of the stab and kill from the inside hypothesis from Carpenter. Unfortunately Carpenter downplays several aspects of it such as the likelihood of a sharp cutting edge and for whatever reason the idea doesn't get much traction, even though it better explains the evidence than what Ostrom suggested or even subsequent works by Manning (2005) & Fowler (2009). Then comes along John Jackson, whom I don't recall if he cited or read Carpenter, but suggests an improved, but still problematic hypothesis, of sickle claw killing. Jackson gets it right I think in assuming a sharp cutting edge and that once the claw had penetrated and pressed into tissue it was free to repeatedly stab and traumatize tissue from the inside. Jackson thinks that the caudal tail rods of dromaeosaurids were necessary for this motion but I have my doubts and the revelation that Utahraptor lost its tail caudal rods but otherwise shows hyper carnivorous attributes supports this. Finally it should come as none too great a shock that the burly iguanodonts, nodosaurs, and sauropods that Utahraptor shared its habit with and which formed its prey base all had a singular vulnerability - a vulnerable neck.



So that is where I stand with what I regard is the leading hypothesis on dromaesaur killing claw function. It is interesting I think not so much for what it says about dromaeosaur killing claws but what it says about us. It is a tale on the transmission of ideas and hypotheses - what counts as a good hypothesis and who is allowed to advance such hypotheses. It also shows how good ideas - though not necessarily perfect when advanced - sometimes get pushed aside or disregarded. Lost in the mix so to speak. But then later on they can get rediscovered, dusted off, and shown the light of day.

I do think that this idea - or collection of ideas, the evolution of a hypothesis via disjointed bits and pieces - will ultimately be one that is nursed back to health, retooled and refashioned.

The Raptor Fossils Project (Utahraptor) w/link to gofundmeUtahraptor



Refs

Carpenter, Kenneth Evidence of Predatory Behavior by Carnivorous Theropods. GAIA no 15 (1998) December pp 135-144 online pdf

Fowler DW, Freedman EA, Scannella JB, Kambic RE (2011) The Predatory Ecology of Deinonychus and the Origin of Flapping in Birds. PLoS ONE 6(12): e28964. doi:10.1371/journal.pone.0028964

Jackson, John. The Secret Dinobird Story December, 2013

Manning, PL, Payne, D, Pennicott, J, Barrett, PM, Ennos, RA (2006) Dinosaur killer claws or climbing crampons. Biology Letters (2006) 2 110-112 pdf


"A Long habit of not thinking a thing wrong, gives it a superficial appearance of being right, and raises at first a formidable outcry in defense of custom". Thomas Paine

It is with a bit of heavy heart that I write this. That it even has warranted this much thought on my part compels me though. I feel we have reached a sort of tipping point and, for lack of a better term, a crisis as goes this circus we call the online paleocommunity. We have been witnessing a startling attrition in the number and quality of blogs, fruitful interchanges, and general positive social media encounters. We have seen some very talented and valuable individuals decrease their engagement or fall off completely within the community. We need to be asking some very hard and difficult questions at all levels. In order to get at these difficult aspects I myself have to play a bit of the heel, the bad guy so it may seem. I am doing this in order to stem what I perceive as a growing burnout, disillusionment, and fatigue within a social community that is actually somewhat new and unparalleled in intellectual history - the online paleocommunity. I think we should take a moment to realize that it is a special and unique place and one worth fighting for. Where else in the history of science have we seen a meeting of multiple strata of interested parties get together in such intellectual, engaging, and profitable way? But there are problems to face and some rather ugly truths and questions need asking. In speaking so bluntly I ask simply for your open mind, reason, and an effort to grasp at nuance. And know that in casting such a wide net I don't fall outside its bounds.

So with that it mind, and I think that is a fair opening statement, we shall proceed.

Special Unique Times With Special Unique Problems

When I was a young grommet of about 10 years of age leafing through Gregory S. Paul's Predatory Dinosaurs of the World for the umpteenth time I had no inkling that one day children of my age, likewise possessed mentally with all things dinosaur, would have unfettered access to not only some of the best minds in the field of paleontology but due to the growing open-access movement direct access to many of the original scientific texts. So if you are a young dinosaur grommet - and I use that term endearingly because I was once just like you - realize that you are living in a very privileged and special time. So don't take it for granted.

But more importantly don't abuse it.

What do I mean by don't abuse it? First off I think for some of these younger paleo-grommets we should burst their bubble as to what the working schedule of a professional academic is actually like, because I think it might be eye opening. Not working as a professional academic myself, but having been around them in various permutations, I'll give you my ballpark estimate of what their daily schedule is like. I would wager that, conservatively, 50% or more of their day is spent doing boring bureaucratic stuff. Yup, exchanging emails, going to faculty meeting, writing grant requests, paper requests, fee waivers, maintaining funding because original research and testing is quite expensive. So the vast majority of time is not even spent on the work they are most known for. If they are  professional academics they are also, by necessity, probably teachers. Some may actually like teaching and thrive doing it. Some probably just teach as a means to an end, a way to allow time for research. In any case you can bet that teaching, office hours, grading, making tests, preparing lab - all that stuff - is gonna take up the bulk of the rest of the time of a professional academic, probably upwards of 4o% although again I might be lowballing this. That leaves  probably less than 10% of time dedicated to new and original research, blogging, writing papers, hypothesizing i.e. "pushing the field further".

In other words - regardless of the actual time break downs - the real "fun" work of paleontology gets squelched into a relatively tiny compartment compared to the obligations of bureaucracy, teaching, and other more tedious details.

And it is somewhere in that 10% of time professional academic have to follow new leads, research, hypothesize, and think of new ideas that their social media time is met too. What does this mean for you young dinosaur grommets? It means that you should not hit up such and such with extreme and lengthy questions, ask for them to do research for you, and don't expect that they have time to consult on your expose or fact check your document. Google it!! Wikipedia!! You have access to more information at your fingertips than we ever did! I'm not going to name any names and it is not my intention for the parties involved to be harassed or shamed in any ways but I recently saw on social media a well known researcher given a list of over 3000 genera with lengths and weight estimates and asked to correct, augment, and fix said list. Please kids, just don't. It might be naivety but realize that time is no luxury for professional academics and the more burdens and requests you place on such people you can expect more and more social media burnout and people dropping out. This is why we can't have nice things folks!!

Now my experience is a bit different as I am not a career academic, nor do I think it was the right path for me in any case. But the crux of the issue remains the same… time. I don't have to sift through bureaucracy nor do I have the responsibility and energy that is demanded of being a teacher. For me my path involved decoupling paleontology from financial realities. Fortunately my day job involves lots of driving and I get to do my best thinking while driving, which is why I have a backlog of ideas and material I have yet to unpack!! Frustratingly the stresses encountered in the online paleocommunity sometime act as a distraction from getting the work done that I need to get done. But the point remains, whether someone does this stuff as a passionate hobby or are career academics those in the online community need to realize that time is our most limiting asset which we need to spend wisely!!

The Boy's Club of Online Paleo - whether we like it or not

Leading from this it is also time we face the fact that the online paleo-community, especially the dinosaur aspect, is dominated by young males. Now, you can ascribe whatever cultural reasons, biases, biological determinisms or whatevers to why this is. There have been some valiant efforts to make paleontology more amenable to female retention and inclusion. Certainly some females may have their perspective on how things can be improved and I'm not discounting their truth but I'm just noting what I see and what I think we will continue to see - a bit of a boy's club. I doubt we will ever see exact parity in the genders for paleontology both professional or in the online community. For now I'm just going to go with an observation of "it is it what it is" and that boys love dinosaurs. Especially the big and violent ones.

From this observation, that a big chunk of the online pale-community (esp dinosaurs) is dominated by young males, we can start to extrapolate some general observations of the young male psyche because that is where the problem (mainly) lies. I'm sorry to inform you young bloods, and I speak from experience, but I'm gonna make a sweepingly blunt generalization that young males are the least empathetic, most anti-social, most cruel, and generally the most vile and violent sexo-social caste in any human population. I'm sorry guys its true. There is a reason that we send you off to war and you do it so splendidly and without question. There is a reason that Lord of the Flies was about a group of boys stranded on an island, not a group of elderly women. There is a reason that behind the vile comments on social media is almost always a young male. There is a reason for Gamer-gate. There is a reason for the alt-right. That reason is young males and all the conditions, trappings, and baggage incumbent upon you.



The Prevalence of Autism & Mental Illness Signals Within the Community

Again this might not be the most deft treatment of the subject but if we start with the observation that young males dominate the online paleocommunity - and that this probably won't change in the foreseeable future - we can start to arrive at better answers by asking the right questions. Before we do that I feel we must address little discussed truths about the online paleocommunity that encompasses both genders and probably run the gamut from novice to professional.

That difficult truth is that I believe there is a higher than normal incidence of mental conditions and mental illnesses in the online paleocommunity. Austism and the subtype Aspergers syndrome I suspect are especially common within the field from aficionados to even esteemed thinkers. An immersive subject such as paleontology provides a natural intellectual pasture where people lacking in social skills and prone to obsessive interests can flourish. Especially online where social interaction is devoid of the nuance of face to face contact and one can literally spend countless hours going down whatever wormhole one finds themselves in. I myself probably fall somewhere on the spectrum to a very slight degree given my propensity to obsess on subjects and really dive into them to an extreme degree.
Working from the perspective that a big chunk of people online might be on the autistic spectrum, have difficulty with social pragmatics, and find a natural refuge in paleontology might prove useful if you are having trouble distinguishing between classic autistic type thought processes (i.e. lack of social cues & pragmatics but no ill intent to harm) or if someone is just trolling (out to harm).

That people who find themselves somewhere on the autistic spectrum might have a predilection towards paleontology should come as no great surprise. I've often discussed the connection between dinosaurs and autistic children with my mom who is a professional child speech therapist, indeed simply google autism and dinosaurs and you will see that there has been much discussion in these regards.

The necessary corollary is one which I have grappled with discussing because I can't really discuss these issues without decoupling them from my own life, so I won't. In addition to the online paleontological community acting as a bit of a refuge to those on the autistic spectrum I also suspect that it attracts a fair number of people who, for whatever reasons, don't exactly fit into most mainstream elements of modern society. I suspect that in addition to high incidence of autism in the community that there is a high incidence of risk factors and associated characters emblematic of conditions referred to, for lack of a better term, mental illness. I say this because when I go down the checklist I meet most of these requirements and I suspect that there probably are a lot like me. I have been visited upon by depression most of my life and even an isolated manic episode. I've had troubles establishing relationships with people, dealt with loneliness, isolation, self doubt, low self esteem, jealousy, chemical dependency issues, addictions, numbing my emotions, and suicidal thoughts. For all my bluster I consider myself and meet the qualifications of being a highly sensitive person (HSP) who probably feels things deeper and more passionately than most. Highly sensitive males are not supposed to be "out" in American society and most are not.

I make the point of mentioning all of these aspects of my life I have sustained and lived through to show that each one of us is carrying the invisible battle scars and wounds of a life lived and invisible struggles not known to others. That, speaking for myself personally, sometimes the slightest poke or prod can unleash a lot of anger and grief barely simmering under the surface.

So when you see someone go off the rails, as I've done it myself, ask yourself: is this person always like this? Did he/she simply have a bad day? Is there more to the story that I don't know?

Online "Consensus", the Perils of Group think and Ideological Bubbles

One of the pitfalls I think we all should be wary of is the dangers of becoming too insular a community.  Such scenarios can quickly establish a path leading towards intellectual bubbles and group think. We also should be wary of calls towards consensus culled primarily from the online community. Such thinking negates the fact that many thinkers, professional included here, abstain from social media discussions of paleontology. They just don't do it. This can also create a skewed impression of what consensus really is and how nebulous a concept it is and will continue to be. The online community does not always reflect the full gamut of thought and opinion.

This creates a self reinforcing intellectual bubble where group think is primed to take over. Why? Because we are social animals discussing science on a social platform. Social primates are going to drift into group think if not steeled against it. Now I'm not going to say this is an insurmountable problem… yet. But we should be on guard against it.

Another pitfall we should be wary of is a tendency for almost a type of artificial democratic voting of ideas and willful confirmation bias. Sorry but this is destructive to the science when ideas are simply voted upon by a delegation not yet amenable to change or with the maturity to recognize that the once solid footing that their ideas once seemed to rest upon is crumbling beneath their feet. Again this is a byproduct of the youth and inexperience of many younger paleo - enthusiasts. Your brain is literally not yet fully formed. And life has not kicked your ass enough. But give it time, it will.

What to Do?

It may seem that I have painted a particularly bleak picture of the online paleo-community. Beholden by hordes of young males; many perhaps autistic; lacking social cues; rife with mental illness, isolation, anger, and the power of anonymity; intellectual fiefdoms developing; egos, egos, egos; large scale disengagement and attrition by any adults in the room; skewed consensus; Lord of the Flies brought to life.

With all of these negatives at hand how have things hobbled along so well to this point? I can only speak of my own personal recommendations and ideas for a more synergistic and positive online experience. I'm very amenable to hearing others thoughts and ideas and am certainly not above reproach or even innocent of many of the criticisms I myself have put forth.

Sometimes Its Good to Just Watch, Listen, and Learn From the Sidelines

Every once in a while I am pleasantly surprised by coming across a new commentator who admits to having read the my blog for some time but has more or less quietly lurked in the shadows. I really like you guys because you remind me of myself a bit. I didn't really get into commenting myself until after lurking for many years, and even now I generally peruse and monitor discussions rather than always feeling it necessary to throw in my two cents. You know, it is not really necessary to always chime in right?

There is a proverb that goes "Still water run deepest" which you may have heard before. Less well known is that there is an inverse to the proverb:  "Shallow water makes the most noise"

"Where the water ran smooth he found it Deepest: and on the contrary, Shallowest where it made most noise." Theres more danger in a Reserv'd and Silent, than in a Noisy, Babbling enemy

Put It in a Sandwich

The following is a rather simple and easily remembered formula to allow a more positive and fruit full exchange of ideas and criticism. When someone puts out a new idea, thought, or piece of art it is always like a little baby. You are going to be a little attached to it. You want to see it do well. When it is attacked it is normal to get a little defensive. Then arguments occur and all kinds of nastiness. This is how to sidestep such quarrelsome exchanges by simply bracketing your (constructive) criticism by putting a complimentary/positive statement both before and after the criticism. In other words put it in a sandwich.

Example of a positive art critique: " What an interesting design (positive opener). Have you come across the article suggesting such a feature was likely not there? (non-condesdending tone allowing person to answer) Again, thanks for sharing your work you obviously put a lot of effort into it!! Keep it up!! (positive closure)"

Is that so hard? And guess what it might leave both parties feeling better than before the exchange!?! Imagine that, feeling better after an internet exchange!!

How much better does the above feel to read and write as opposed to this: "I doubt it, that's kinda ridiculous. That is not how these things work."

There might be a good reason for the person doubting the accuracy of a picture. But have they given that reason? Nope they have not. Have they assumed that the person who did the picture has not read what they are speaking of? Yes, they made an assumption. Is it condescending? Yup. Have you learned anything or have you become more enlightened in any way? Nope and nope, in fact you probably feel a bit crummy.

Avoid "gotcha" statements, those are the worst. You can inform someone else about some knowledge they may not be privy to without being a holier than thou, know it all.

And finally take a loooooooong look in the mirror if you are the person always leveling criticisms at others without producing anything of your own. Your constant nit-picking and criticisms reflect more on your own dissatisfaction with yourself than a genuine desire to better and help out the other person. Take that cold shower.

If the ratio of criticism to creation is overly high in your online footprint you are part of the problem.

"Those who can, do. Those who can't criticize." Robin Sharma

Learn to Walk Away

Just do it. Walk away. It's not worth it. There is hardly ever a final word in most issues in paleo anyways.

If you are always getting into tifts maybe it is time to take a look in the mirror. Is it really because you are so superior and everyone else is a dumbass? Maybe when you realize that the common denominator in all of these exchanges is yourself then you can see where the problem lies.

Don't Be a Stalker or a Harasser

This has happened to me several times already. If someone bans you in one social media outlet do you take that as an invitation to find them on another and contact them there? If so, that is in my book stalking/harassing behavior and it does not feel good. It feels like what it is, a violation. If you do this you are part of the problem.

Realize that paleontology is more or less intellectual entertainment, a hobby. Even if you have a point if its got to the level of someone blocking you or disengaging from the exchange, just leave 'em alone. Walk away. It's not your job to be the self appointed grand poo-bha of all thing correct and true. No one owes you their time or to give you a forum, these are voluntary exchanges, not mandatory.

Don't Say Something to Someone That You Wouldn't Say Face to Face

Pretty self explanatory right? I'm guilty of not following this one myself sometimes. Maybe we all can get too easily emboldened by a type of anonymity and keyboard warrior bravado that the internet provides.

What you say on the internet, you own. After saying enough crappy things that becomes you. We should realize that even if we are discussing someone who is not currently engaged in the conversation - that doesn't mean that it won't get back to them. So think a bit about what you write.

Don't Pile Up On People

Even when someone behaves egregiously and have already been called out on it, don't feel like you have to dog pile on that person. Are you doing it for beneficial reasons or are you just trying to get your shots in? People are not defined by one post, by one drawing, by one exchange, or by one action. We have good days and bad days. Allow for some nuance in life. 
 Conclusions: A Better Version of Our Online Selves

I sincerely hope that people get the gist of what I'm saying. Granted that a big portion of my readership is actually the "young male demographic" which is the group I am most singling out and criticizing I do this at some risk. But I think a greater good is at stake and that is the strength and vibrancy of the online paleocommunity. I'm not the only person to notice a diminution of upper talent and people generally suffering burnout and attrition. So I felt compelled to call a spade a spade and if that means I got to play the heel, play the disciplinarian, give the masses of paleo-grommets a spanking, so be it.

Just know this: If you are 15 years old, what do you now think now about some of the things that the 10 year old version of yourself said online? You probably think of things a little differently now with more knowledge and life experience, right. Now with this observation in mind is it not too difficult to imagine that what you say now online at age 15 might be a tad different that what you say and think when you are 20, 25, 30? Remember what you say online you own so be careful about this, some things may come back to haunt you.

That also goes to giving a little credence and respect to any adults in the room. Remember in most cases that they have been in your shoes, they have been young paleo-grommets themselves. They have the intellectual context to have seen the oscillations in scientific discourse bounce back and forth before. To put it bluntly they have already forgotten more than you know. I'm not saying the adults are infallible or that you have to worship them or follow blindly. But let's interact in a way that preserves peoples sanity and does not drive them away. Because when all the adults are gone, and many are already leaving, what do we have left? Lord of the Flies is what we have left.

Neovenator sasterii rostral facial nerves. credit Darren Naish

Sensitivity… not usually a word associated with flesh rendering beasts of yore. However the evidence is in and it seems unequivocal. The most celebrated of ancient predators, the theropods, were equipped with high facial sensitivity. Sensitivity, not just of the face but as a package of characters very emblematic of wide variety of animals including ourselves, is a word and concept we need to explore and unpack both culturally and biologically in order to better understand creatures that are actually both cultural and scientific creations. And in doing so I think we will learn more about these animals... and ourselves.



The Cultural Baggage of "Sensitivity" in Humans and Animals: Towards a Unifying Concept

Emotional sensitivity is generally ascribed a feminine quality in western cultures. We don't often ascribe connotations of sensitivity to those human conquests most adventurous, daring, "hyper masculine", and audacious in scope. Sensitivity is usually associated with the weak, indulgent, melancholic souls, too indecisive and wavering to get in the fight or even pick a side… That we have these cultural inscriptions, at least in western culture (especially in America), which are in turn enscripted into gender normative roles is an important concept. The feminine becomes the loci of sensitivity and, presumably, all those features incumbent upon such a character, namely whatever masculinity is not supposed to be; easily overwhelmed; dismayed; and petulant. The masculine defined more by a lack of sensitivity than anything else - stoic, distant, strong and silent - unsuited to express any emotion save anger.

It is interesting and perhaps perspective changing when we look at the two main definitions of  "sensitive":

1. Quick to detect or respond to slight changes, signals, or influences.

2. (of a person or person's behavior) easily hurt or damaged especially: easily hurt emotionally: delicately aware of the attitude and feelings of others.

If we had to make a choice I think most would drift towards definition #1 when thinking of an animal's sensitivity,  focusing more on external stimuli especially as picked up by the "classic" recognized senses. When discussing human sensitivity I think it fair to say that most would drift towards definition #2, where the classic senses are eschewed and the impetus is placed more on emotional cues - both external and internal - as a dominating influence to a sometimes overwhelming degree. Note that in definition #2 the words hurt, damaged, and delicately are used. It is clearly not a good aspect in a person to be emotionally sensitive based on this definition. Sensitivity is conveyed as a weakness, not a strength. Of course, for me personally as a HSP (highly sensitive person), I would highly challenge this notion. However, at least in western societies the conceit remains - being overly emotionally expressive, empathic or "feeling" others emotions is seen as a weakness or shortcoming.

Interesting that there is a bit of a dichotomy in thinking of what it means to be a sensitive animal versus a sensitive human, especially given that we are all technically animals. But this dichotomy is not at all incongruous with our tendency to place humans outside of nature and removed from the behavioral patterns and tendencies of other fellow animals. Does our focus on emotional sensitivity in humans speak more towards a tendency to not only distance ourselves from "the animals" but also disavow our other senses? Does out tendency to highlight the classic senses of animals but diminish their emotional sensitivity likewise further distance us from animals and justify our treatment of them? Could these two separate definitions be combined more succinctly into one unifying concept of sensitivity in sentient beings of any species? I think so and I think such a definition is far more useful and practical despite whatever discomforts and cultural conceits such a definition arouses.  For me there is much more utility in a definition that encompasses sensitivity in animals and humans as an ability to read incoming stimuli from the outer environment that includes not only sight, smell, hearing, taste, and touch but a certain emotional capacity to display and interpret the "vibe" of other sentient animals, even other species.

Despite what I think constitutes a more holistic and encompassing definition of sensitivity we are still left with the (western) culturally enmeshed judgement that heightened "emotional" sensitivity is bad and linked to the feminine BUT heightened sensitivity in other arenas (smell, sight, hearing, touch, taste) is generally valued and revered in people. In fact other being sensitive in other senses is given a lauded and super power status.

Let me pull a Quentin Tarantino tactic (Kill Bill II David Carradine speech towards the finale) and use the comic book super hero analogy to drive home my point further. We've all seen comic book super heroes endowed with super senses; the superman ideal able to see through buildings, hear at infinitesimally low levels etc. etc. Funny that we appreciate and envy such super senses in our super heroes but have you ever heard of a superhero blessed with hypersensitivity on an emotional wavelength? Nope, I'm quite sure that you haven't. In fact just the thought probably arouses a slight chuckle in you. There is no highly empathetic, intensely emotional marvel super hero. Stan Lee did not think of that one. Still emotional sensitivity is seen as a negative i.e."Stop being so sensitive,", "You need a thicker skin,".

Yet if we imagine that reading, reacting, and displaying intense and nuanced emotional information is just another sense - like hearing, smelling, taste, touch, or vision - that is imbued into humans to varying degrees (or more animals than we might be comfortable to admit) then it stands to reason that such an ability has adaptive benefit to the individual and to the species. In humans this is self-evident despite our cultural and gendered normatives grafted upon highly emotional sensitive people. In animals, such as the large macro predatory theropods, being highly sensitive to the emotional cues of other members of your species would have been extremely strategic and adaptive because they could literally bite your face off. Try telling a pair of Tarbosaurus bataar engaged in courtship ritual "not to be too sensitive" and both partners would likely reply with (if they could) "fuck you man, I got to read every nuance of this other monster's emotion because they could bite my freaking face off!!"



"You are too sensitive", "stop being so sensitive"

Admonishing humans for being regarded as too sensitive emotionally is a culturally enmeshed tradition, not necessarily congruent with the adaptive real life brutal Darwinian realities of existence where hyper-sensitive attributes can be life saving. Heightened awareness of emotional cues , readings, and "vibing" things out has obvious and palpable survivorship benefits not just for the individual but for the group. Only in the unnatural setting of culture and society can such benefits be seen as negatives. Such an interpretation is congruent with many strands of feminist theory. In a patriarchal society both men and women are punished. Given that an especially high degrees of emotional sensitivity is equally represented in the sexes, when signals of overtly high levels of emotional sensitivity are displayed shaming and punishments are doled out i.e. "don't be so sensitive", "only women are sensitive" etc etc in a patriarchy. Such punishments are fear responses meted out when something arises that does not fit the mold.  A spider is seen on the wall, smash it. A snake in the garden, kill it. Scapegoat it. Silence it. What is actually a strength and benefit to the individual and species is hammered down and shamed into silence together with a concomitant psychic and emotional paralysis for the person shamed and shunned. Saying someone is "too sensitive" is the equivalent of saying someone can see too well; hear too acutely; or have too refined a palate. It is a damning indictment on the current status of many cultures, but especially western, that the sense of empathy and emotional fluency is the only sense that is routinely disavowed and squashed - especially in men but to some degree in both genders - BUT is exactly the sense that needs to be heightened in order to combat the ills of the modern age.



It is also interesting that many of our most vaulted and celebrated animals - often times seen as symbols of courage, conquest, and power - are actually the most intensely hypersensitive of animals. And therefore, more acutely gendered as feminine. Cats for instance have always been associated - and often times reviled and persecuted - for their association with the feminine. Also highly sensitive. Including all those warlike symbolic gestures towards lions and coat of arms. Sharks, also highly sensitive and much more nuanced in social behavior than we might generally think. Crocodiles are surprisingly delicate lovers and more than equipped with a suite of features most accurately described as highly sensitive. Many theropods sported (or still sport) a panoply of highly sensitive qualities, including extreme facial sensitivity.

Ironically, western cultures in their disavowal of emotional sensitivity in males have negated some of the most powerful animals as sources of identity - as "spirit animals" - per se. Powerful and predatory felids go to the girls. Sharks and crocodiles, sorry guys if you disavow your sensitivity you don't get to keep them, they too go to the girls. And the penultimate insult to the male ego, those awesomebro predators of yore, they hypersensitive theropods - the girls get them too. Guys we are left with freaking water buffalo. Yup and other big stinky herbivores, omnivores and other "prey species". And dogs, woopty-doo, as if anyone had to ever work hard to earn their respect.

Maybe, in a post presumably about the sensitive snouts of theropods, you were not expecting a neo-feminist thesis illuminating the need for contemporary H. sapiens to reclaim not only our emotional sensitivity as a species for both sexes, but our place within a pantheon of emotionally sensitive animals. It should not be too surprising that I blend the cultural withe the scientific, that has been a constant theme of this blog, and one I will continue with even if some find it distracting, biased, or not rigorous enough. Dinosaurs especially, but really all animals to some extent are a blend of the scientific and socio-cultural-mythos.


You may want to skip to 2:50 to see the shark overwhelmed by the sensory input from the world. Sheesh, that shark is just too sensitive for the world!!

Face Nuzzling in Humans, Felids, Crocs, Birds and Monster faced Theropods

H. sapiens fits within a pantheon of sentient beings that has finely attuned neuro-sensory capabilities not limited to classic senses, but emotional ones too. While nerve endings are concentrated in our hands as well as our genitalia - we also share a highly sensitive oral region with the animals in discussion. A finely attuned and sensitive snout that is perhaps quite capable of soothing social relations and establishing long term pair bondings…

http://avangardphoto.com / Mario Caputa CC3.0

That a highly sensitive snout/oral region evolved in our species, presumably for such tactile benefit as regards sexo-social relations, despite the lack of an obvious exaptation for such behavior in our species should give us moment to pause. Humans do not explore the world or handle prey via their mouth, unlike the other animals I will discuss, but via their hands. That we independently evolved face nuzzling behaviors should awaken our curiosity. The self reinforcing and adaptive philosophy behind such behavior is simple: face nuzzling engenders activation of nerve endings, which in turn begets pleasure centers, which then enhances pair bonding and what can be dubbed "emotional attachment" and finally disarms the violent, predatory proclivities of several of the species I will mention. The net result is that those individuals that face nuzzle, reproduce more often and more successfully, and their progeny do the same.




If the extant phylogenetic bracket is your thing we have abundant evidence of both crocs and birds showcasing face nuzzling within the context of mating/pair bonding.





Where to put theropods in this pantheon? Probably starting somewhere between crocodiles and albatross is a good ballpark. Theropods do appear to have long incubation times, their clutches were larger than birds but smaller than crocs, and due to their high metabolisms it would be hard to hunker down and babysit a nest for a month or two in a solitary fashion. The responsibility for nest and clutch guarding likely fell on the shoulders of both parents to some degree.

In terms of parental care of the hatched offspring I like to think of theropods parents as a bit like delinquent parents: "Yeah, you can hang around here for a while, even nibble a bit on my leftovers. But look I'm not gonna baby you, you should go out and get your own food and hang out with your clutch mates for the most part. Did I mention you are freaking annoying sometimes? And if shit hits the fan, if I can't feed myself, yeah I'm gonna eat you? So you better grow up and move out, pronto!!"Again, somewhere between crocodiles and birds is a good place to start from in these regards. With a sprinkle of some cannibalism if the need arises. (See I did not go all hippy-dippy, lubby-dubby on you, just mainly)

REJOICE by Duane Nash

It should not at all be too obvious that I went to UCSC where nekkid hippy chicks frolicking through redwood glades was definitely not a thing… No apologies for the gratuitous female flesh, I'm still a dude after all. Some of my fondest memories as a kid were sneaking through my dad's Heavy Metal comics. Some where along the line bewbs paired up with prehistoric beasties became something not to do despite the fact that everyone loves Mesozoic beasties and bewbs. That such Boris Valejo type art might now be considered a bit backwards, a bit passé, a bit too boys club, this makes me sad.  Women and theropods are a natural pairing!!

Apart from that slight observation of perhaps an over political correctness what I really want to illustrate is that if we take this hypersensitive facial business and face nuzzling behavior to its logical conclusion in theropods there is quite the argument to be made that pair bonding between theropods and big brained, tactile, and empathetic humans is possible. Start with a young theropod and form that physical bond early, especially along the sensitive facial areas, and you have a friend to the end!!




It's actually an idea not outside the bounds of possibility… If humans could endear themselves to theropods at a young age and strategically take advantage of the facial sensitivity of theropods then we could see such a union forming per chance. Such facial sensitivy in theropds, if it was used for face muzzling, would also engender a heightened or hypersensitive emotional ability to read the other theropods intentions. Why? For the simple fact that if you are going to get close enough to face nuzzle you better be damn sure your presumed partner doesn't actually want to bite your face off!! Such an ability and need to "read" or "vibe" out your presumed partner would also engender more committed physical social cues. These could include ritualized head, body, tail movements i.e. "dance" moves. Also certain display structures that could be flushed with blood or inflated to various degrees to express intent. In mammals we have exquisite facial muscles, giving us highly communicative expressions. In many mammals it is the ears, especially in dogs, that can be used to express emotion and intent. Theropods, bereft of such facial muscles and communicative expressions - would invent other alternative modes of communication. The ability to flush with blood areas of the face and forequarters to show intention. Inflatable gular sacs and other fleshy display structures. And of course flesh antlers, the highest potential for and use of likely occurring in tyrannosaurids. Don't be so surprised when you notice that after we see a decline in the size and extravagance of hard tissue crests, lacrimals etc etc which seem to have peaked in the early mid Jurassic we see larger and larger supra temporal fenestra in many predatory theropods, especially tyrannosaurids.

The False Positive of Theropod Facial Biting

I think one of the more fascinating aspects of paleontology - and really paleoculture, because there is a constant dance between the culture and the science - is a certain appreciation of the oscillation of ideas. Unfortunately this oscillation can only really be appreciated with age and experience. For instance in my lifetime I have seen the wobble of Tyrannosaurus locomotion go from vertical tail dragger, to horizontal 45 mph speedster, now going back to a power walker. It still might oscillate some more, but I think the oscillations are getting tighter and tighter and we might be honing in on some truths. Younger enthusiasts might today scoff at the notion of tail dragging tyrannosaurids but need to realize it was some of the top minds of the time positing this stuff. To suggest that todays "top minds" all of a sudden are going to stop making mistakes - not the same ones but different ones - is naive and incongruent with the history of paleontology.

One idea that I think is due for a bit of an oscillation is the notion of face biting theropods. It has taken on kind of a dogmatic lore lately. I think that there is a notion out there, not really challenged, that a typical day in the life of a large carnivorous theropod went like this: "Wake up. Walk up to another theropod. Gnaw on each others faces for a bit. Eat something. Gnaw on another theropods face. Go to bed. Have dreams of gnawing on the faces of theropods. Next day repeat."

The question or challenge I posit is not that theropod face biting was not a thing, it clearly was, it was just not as much a thing as we are making it. Instead of a documentation of a daily ritual of antagonistic clashes, face biting represents the occasional lover's quarrel or a truly aggressive encounter for dominance, territory, mates etc. etc.

Towards a More Nuanced, Complex, and Varied Theropod Social Dynamic

I think that the startling and profound facial sensitivity of predatory theropod dinosaurs really pushes us to consider an increasing likelihood of a profoundly socially complex animal. Not necessarily socially complex in the same way primates are, or mammals in general, but by splitting the difference between modern crocodiles and aves we can hone in on some distinctly possible truths… or at least a modicum of truthiness. Having such social bonds established via feedback loops - i.e. face nuzzling behavior - is rather simple and straightforward. I suspect that facial sensitivity originally was furnished in prey manipulation and later proved a fortuitous exaptation that mollified aggressive tendencies and allowed pro-social behavior. Such pro-social behavior does not necessarily invoke a high canid or primate type of intelligence, altruistic behavior, pack hunting or other overtly advanced symptoms of "highly complex social behavior". It does not negate the possibility either. But I think as a baseline face nuzzling has some patently obvious benefits for peacemaking capabilities both between and among the sexes in predatory theropods. Basically enough tolerance generated for the animals to capitulate to, "OK this feels kinda good and pleasurable when we do this, I won't bite your face off. We can both stick around and take some turns guarding this nest of eggs we created." Seems like a win-win right? Predatory theropods would get some pleasure through face nuzzling, not get their faces ripped off, and win the genetic sweepstakes. Seems like a pretty good feedback loop, no? Those theropods that could nullify their aggressive tendencies through face nuzzling would have the best reproductive success because they would stick around long enough to share clutch watching duties…

 I'm gonna leave this here…


And this is an important point that I want to stress here… egg incubation times for dinosaurs might be pretty darn long. Somewhere between incubation times for reptiles and birds is what we might be looking at for an average. Having an incubation period of several weeks or even months poses some profound difficulties for high metabolic rate large terrestrial predators. First of all it would prove difficult to go the route of mother crocs and simply hunker down on the nest for several months, the caloric and water needs would be too high for predatory theropods. Unlike large sauropods, hadrosaurs, and other herbivorous/omnivorous dinosaurs predatory theropods could not simply form huge colonies that overwhelmed the local ecosystem with eggs and babies - they did not have equal population densities.  Finally predatory animals would have to abandon the nest for some time in order to forage, they don't have the luxury that herbivores or omnivores have in these regards. These simple deductions push us to consider two or more predatory theropods sharing clutch guarding burdens. It does not necessarily even have to be a classic monogamous male-female alliance. It could be a sisterhood that grew up together since clutch mates. It could be an alliance of male brothers that likewise came of age together. Or some combination there - of, there are actually a lot of alliances that could crop up. All of which were fostered and ameliorated via pro-social face nuzzling behavior.

Again let me state crystal clear the link - long incubation times and the realities of predatory ecology - push us into a realm where pro-social bonding behavior and shared clutch guarding duties become a very palpable possibility. I would say the favored image actually.

I realize that there a lot of other suggestions for high theropods facial sensitivity none of which are mutually exclusive to the scenario I have painted here. I though about discussing those ideas here but I think that is enough for now. Gonna have to revisit the other ideas in future posts, I also have heard of some other info coming down the pike…

For this post I also made some quick and dirty Youtube clips to sort of a give another avenue and thought document to these ideas. Gonna see how these work out, hopefully the video can work in conjunction with the writing and the illustrations to better drive home and express these ideas.





Best,

Duane



Refs

Barker, C.T., Naish, D., Newham, E., Katsamensis, O.L., Dyke, G. 2017. Complex neuroanatomy in the rostrum of the Isle of Wight theropod Neovenator salerii. Scientific Reports 7, 3749

Carr, T. D., Varricchio, D. J., Sedlmayr, J. C., Roberts, E. M. & Moore, J. R. 2017. A new tyrannosaur with evidence with evidence for anagenesis and crocodile-like facial sensory system. Scientific Reports 7, 44942.

Ibrahim, N., Sereno, P. C. Dal Sasso, C., Maganuco, S., Fabbri, M., Martill, D. M., Zouhri, S., Myhrvold, N. & Iurino, D. A. 2014. Semiaquatic adaptations in a giant predatory dinosaur. Science 345, 1613-1616.

Naish, Darren. The Sensitive Face of a Big, Predatory Dinosaur. Scientific America. June 16, 2017
https://blogs.scientificamerican.com/tetrapod-zoology/the-sensitive-face-of-a-big-predatory-dinosaur/

Tanke, D. H. & Currie, P. J. 1998. Head-biting behavior in theropod dinosaurs: paleopathological
evidence. Gaia 15, 167-184.

In case you didn't see this coming... well its not like I haven't been dropping hints all along... that I have always had in my back pocket some rather challenging and interesting ideas on how this whole beast of scientific process/communication can be improved, augmented, streamlined, and made more inclusive. That these thought will now be made manifest is here. So hey, if you thought this blog was all about making dromaeosaurids nasty again, plesiosaur machinations, bottom punting hippo Spinosaurus, night stalking T. rex, or droopy lipped sabertooths - well I played you a bit there, as I never really gave away my full hand. Not only will I outline how such an OPEN SCIENCE system can operate I will boldly proclaim that such a system will greatly augment and inform a robust citizenry of science, reclaim sciences status in the world, and usher in a new era of spiritually strong scientifically minded peoples.

I have given the issue much thought, not as yet succinctly expressed. While at once I saw my lack of a peer reviewed publication record as a weakness, I now see it as a badge of honor.  

Some online voices have tried to construe a bit of a false narrative that it is Duane Nash vs. the establishment when in actuality quite a few people in what may be deemed "the establishment" are quite amenable to my ideas and do express to me, mainly in private, that they see the logic and merit in many of my ideas. So personally I don't quite buy the idea that it is this "Duane Nash vs. the establishment" trope as some have tried to convey, although I can't deny some truth to it (wink, wink). However I do recognize that some researchers might feel some consternation that they can not properly cite or comment upon my ideas as they are not "in the literature"and in doing so they might unwittingly open the floodgates for all sorts of online self publishers feeling the need to be "cited". That opinion is due to a culturally enmeshed and unnatural byproduct of the system we are in engaged in, where it is the peer reviewed scientific paper that is the only word that seemingly counts in the minds of most. But this is a cultural notion - it is not a law of nature - and like all cultural notions it is prone to be re-imagined, made over, and transmutated in new and exciting ways. So no, it is not really about Duane Nash vs. the establishment it is about Duane Nash vs. the system. It is the system that is the problem. And it is the system that needs fixing.

It's high time that the modern peer review format goes through such a deconstruction and reconfiguration. Not, as some may wrongly be assuming, by abolishing the peer review process but by dramatically ameliorating the process of peer review in an exponential way. At the same time dropping the curtain on scientific process and controversy, making both creators and reviewers accountable to their words. Creators will face more levels of scrutiny and question but they will also benefit from exponentially more collaboration and insight. Creators will no longer be held at the mercy of their reviewers as reviewers will no longer be anonymous and their critiques will be displayed to all. The inherent collaborative and synergistic methods of a truly free and liberal OPEN SCIENCE paradigm shift will dramatically and irrevocably speed up the process of science. Science operating at maximum RPM. Contrary to what many may fear I advocate, as sort of free for all of self publishing anarchy I actually hope to curtail that pitfall. By allowing any and all to submit their idea or work in whatever format or state of finality they choose all are given a shot and subject to online review. Therefore charges of "ivory tower" orthodoxy, academic bias, and in-group out group shenanigans get cut off right at the root. The lone wolf outsider, forever reeling at the unfair treatment they suffer from "the establishment" will be a thing of the past. In short the future of scientific communication as I envisage it will combine the best elements of the peer review process and the social media, group sourced, immediacy of "blogging" format while eschewing the problematic elements inherent in both practices.

Some bold claims Mr. Nash how can this be achieved? The process as I will lay out is disarmingly simple and intuitive. The paleontological community, both online and off, already has all of the tools at hand ready to implement such a system. As such the paleontological community can serve as a bit of a test run or trial run for how such a system can be utilized in other sciences. It is a bold and exciting new frontier as I will lay out and one paleontology is optimally positioned to be in the vanguard of. As you will see too I am not solely creating or imagining this revolution… it is already happening with or without me and is happening with or without your permission. I'm just a messenger.

Before giving a rundown on how I think the peer review system/science communication needs to be revamped I will be running down some of the major flaws and grievances of the current system. As I do this I challenge you, the reader, to start formulating ideas and hypotheses on how such a system can play out. I also invite you to start entertaining potential problems and pitfalls of such a system and if I offer reasonable guards against such situations. This is, in effect, an experiment being run simultaneous to the reading and I do it to illustrate the manifest benefits of a truly OPEN SCIENCE paradigm shift.

Breaking Through the 4th Wall of Science Engagement

4th Wall: That semi-porous membrane that stands between actors and the audience.

Let me explain this analogy. We have to imagine the scientist presenting his/her findings, ideas, or better yet their "creation" analogous to the actor or performer in a live audience setting giving their presentation or work - their "creation" to an audience. We imagine a sort of 4th wall that separates the actor on the stage from the audience, likewise in the presentation of scientific material there is another 4th wall separating the creator "the scientist" from the viewer or in paleontology the, often times, informed enthusiast. Does this mean that the informed enthusiast is not on the same level? Usually they are not. But not always. As I get to the how part of this process I will explain how the two can be teased apart for the benefit of all. And how valid criticisms or observations can and should be documented, heralded, and archived in the process at all levels, yes, even if it is from a non-professional towards a professional.

These binary divisions are becoming more and more cumbersome and transparently ill-informed. Many of the greatest paradigm shifters in paleontology came up with the bulk of their life's work as undergraduates and several prominent names (Jack Horner & Gregory S. Paul) never graduated with advanced degrees in paleontology. Robert Bakker was formulating the basis of his ideas as an undergraduate. Contrary to a prevailing notion that your thought or opinion only can be viewed with credibility upon receiving that PhD pigskin participants in such programs readily concede that yes, their education was important, but it is not the be all and all of what makes a good scientist or thinker. There is a reason that we have the acronym "P.iled H.igher & D.eeper" and most graduates will begrudgingly or willingly concede some truth to this notion. So no, there is not some arcane wisdom or benefit conferred simply upon receiving a PhD, that now - and only now - your voice matters and carries more weight than it did before graduation. Such graduates are in many cases useful scientists, yet in others such a title merely amounts to union membership.

As always it is the merit of one's work or ideas - whether advanced graduate or no - that is what matters the most. Not how extensive your C.V. is or the "impact factor" of the publication you are published in.

All this being said - you still need to learn and become educated in the basics of paleontology - anatomy, geology (especially sed & strat), chemistry, biology, ecological theory - among others. And yes, even though I don't highlight my own education I have a minors in geology, major in physical anthropology, taken classes in anatomy, ecology, biology, science illustration, chemistry, anatomy and all the basics. My main teacher has, and continues to be, my curiosity.

The Scientist as Creator, as Artist, as Owner of their Work

There has been a revolution in the creative arts, one that has firmly placed creative control back in the hands of the creator. And wrested it from those that seek to profit, exploit, and manipulate artistic works. Probably the most apt analogy is the revolution that we have seen among independent musicians and how the internet has allowed them to carve out a niche of complete artistic control, autonomy, and outreach to fans. What the internet had done is broken the monopoly of the "recording industry" that prior to the internet was the intervening party that artists needed to record their art and have it marketed to an audience. The internet has broke up this domination and now artists can market, engage, and create independently from a record company. This also allows the artist complete ownership and control of their work. While the break up of the gigantic recording industry has meant a loss in giant revenue streams as fans can and do download off the internet, use listening apps, or simply buy individual songs - such a new paradigm has allowed unfettered artistic freedom, outreach, interaction, and ownership for the artist.

Science and scientists need to take a page from artists.

And this means, in no uncertain terms, a complete disruption, cancellation, and termination of a relationship that is cumbersome, slow, parasitic, inefficient, egotistical, and arcane. That relationship is the one between the scientific peer reviewed publishing houses and the creator - the artist - whom actually makes the hypothesis, tests it, and does the real work of science. That abusive relationship needs to end…. yesterday.

While the internet has parked revolutionary changes in just about every facet of modern life the revolution promised in science has only been piecemeal. This has more to do with a culture of science, a staunchly conservative culture handed down to us and not necessarily congruent with the mindset, aspirations, and ideals of the vast majority of modern practitioners of science.

Sins of Our Father. Abuses & Iniquities of the Peer Review Process

Sins of our Father. Biblical reference; sins and iniquities passing from one generation to another.

One of biggest sins of the modern peer reviewed publication process is that it so obviously not fun. I don't know when it became this way or when the exact transition occurred but we have now landed in a place where science as it is communicated today is the antithesis of the creatively rife and anarchic pursuit of knowledge that it actually is. It became boring. This is the ultimate sin that science communication has suffered at exactly the same point in our history where we need to be engaging more and more people to think in a scientific manner. If science is in competition with an IKEA furniture assembly manual for the most boring piece of human literature ever contrived science deserves to lose the battle for the human spirit. And science will lose this war if we continue down this path.

It was not always this way, nor does it have to be mandated that science communication must be so devoid of the human touch: that it is clinical, non-stimulatory, and devoid of any and all touch of humanity or spirit that reading it is akin to an instructional manual. If you go back and read the scientific texts of many of the great natural history writers of the 19th century they were rife with anecdote, wit, and a human element. Why did we stop? Are we really under the illusion that by scrapping any and all notions that an actual human is behind these papers that they are themselves devoid of biases, shortcomings, and imperfections… you know like we all are? That by scrubbing the scientific literature of any notion that, you know, an actual human is behind this thing and not some machine? What is more dangerous: the danger that you know or the danger that you don't? By dressing up scientific discourse in a neat and tidy little pant suit we are giving the false pretense that what is in said paper is true and better than what might be said in a sloppy blog post. I beg to differ. If a sloppy blog post is your average street hood a scientific paper is your white collar criminal. Both have faults but one gets away with more due to its glossy and neat appearance. Show me the warts and all.  Show the process. Deconstruct the whole system and rebuild a better one.

That these sins of our fathers - the patently obvious flaws within the modern peer review system - have been heralded and noted is evident. Who has been most vocal about the flaws within the system? Well the very practitioners of the system themselves we are talking about: publishing academics  i.e. "teh workers""the authors".  I've followed enough academics in both social media and elsewhere to garner a pretty thorough list of the grievances:

Pay to Play: Any self respecting DIY punk rawker should gawk at the sheer lunacy of this system. Again, scientists should take a page from independent artists when thinking about their work, how it is distributed, and who benefits (financially) from it. You often have to actually pay money to submit your paper for publication. Yes, there are ways around this, but the point stands: pay to play sucks. Pay to play as I use the term here refers to struggling new bands literally shelling out money to get a slot on larger tours. Sharon Osbourne was notorious for doing this to small bands on Ozzfest. More reason to hate Sharon and peer reviewed publications.

Obviously the system I will layout would eschew any sort of pay to play shenanigans.

Paper Owns the Right to Your Work: Now I might be misinterpreting this a bit but I think in broad strokes I am right. After you do the work, synthesize the results, submit and pay for process and publication it is the paper, not you the artist, which owns the result. HOGWASH!! Again, any self respecting punk rawker would gawk at this system! Scientists - who are actually creative artists - need to take a page from independent artists. Again the analogy to the parasitic recording industry who seize control and rights of music - that they did not make - and hold bands/artists hostage with parasitic and ridiculous contracts and sleazy deals is apt. Scientists need to get their liberty spikes up in anger and defiance about the egregious system that they have been beholden to for far too long. Other creative ventures have left the scientific community in the dust in terms of owning, empowering, and controlling their creative product!! Wake up scientists all the tools are already at hand!!

Again, in the system I will present the creator has complete control and rights to their creation - their work. By now you should be starting to piece together what I will be presenting as the new paradigm of scientific discourse and you should be coming up with some potential criticisms of what I will present. That is good and how it should be… but don't be too shocked that I have anticipated and dealt with many of these problems as you will see…

"Peer Review" Really?: I'm not going to mince any words here and I'm going to hone in on some very harsh and difficult truths we should all look at… unflinchingly. I suspect that the reason a lot in the  academic world look down in disdain at bloggers, self publishers, those that come in the back door so to speak is that we show open defiance and disdain for a system that they themselves don't like or enjoy. It is less about "does this blog make a good point?" and more about "if I have to suffer through inane formatting technicalities, grueling and idiotic reviewers and all this other soul-killing bulgerdash why should I give a blogger who doesn't go through any of this - admittedly - inane bullcrap the time of day?"I don't even need to conjecture here, Jingmai O'Connor, a lightning rod in the blogger vs. published paper debate, says so much herself:

"Aren't we all forced into this stupid world of publication rates and H-indices and what not?"

Yes it is a stupid world but no, Jingmai, we are not forced into it. Most just willingly succumb to the system because they can't imagine a better one. More on Jingmai to come and you might be surprised I agree with her fundamentally on one important, probably the most important, principal that I will delve into later.

Now I'm not saying that there are not good reviewers out there or that they don't for the most part help and assist to make a better product. To take the analogy to the music industry further a good reviewer can be like a good producer, they bring out the best in the artist and cut and trim away the problematic parts.

But let's get real about some, just plain stupid, aspects of the peer review process:

Peer review, in today's parlance, amounts to a sort of blessing. That what is said in a paper is true, good, and can be trusted. However when we deconstruct what peer review actually encompasses, how indefinable it really is, and really hone in on the problems inherent in the system that blessing, becomes more of a curse.

Reviewers are anonymous, unpaid, and often times limited to just two?!? I suspect a lot of younger paleo-grommet enthusiasts have this fantastical idea that peer review is this very involved all encompassing type of thing with a literal army of leading workers looking over every last detail and scruple. Not the case. Again often just two of them. And since they are anonymous if they make a mistake or overlook something guess what type of repercussion do they get? Nothing?!? That's some bullshit if I ever heard of it.

In the system I will present work is presented in it's raw form for all in they system to look over, analyze, and critique. The review process is therefore group sourced and made transparent for all to see. No more anonymity. Not just two reviewers but in fact dozens if not hundreds. Again, you the reader, should already be piecing together what I will be suggesting as an improved model for science communication, putting together the pieces and formulating critiques. This is science in process. This is OPEN SCIENCE. The creators can take and synthesize criticisms and update/augment/change their work in real time. Imagine that, people see science working!!

And finally did you know that people submitting papers for review can deliberately request that specific parties don't act as reviewers?!?! Conflict of interest anybody? Can it be laid any more bare?

Some may have been working under the premise that bloggers, self publishers, i.e. people coming through the back door are seeking to circumnavigate the peer review system. In my case at least, you couldn't be further from the truth. I am hoping to exponentially increase the net of review. But doing it in such a way that unscrupulous reviewers will be exposed as they can't hide behind a cloak of anonymity and that the scientific creator has tools to not be "at the mercy" of reviewers.

And finally, and most damningly, no one can actually define or quantify what are the responsibilities, tasks, and essentially the rubric for what it means to be a reviewer? It seems every reviewer has their own method and criteria for what they want to check and how in depth they want to go. Given that reviewers are anonymous and not paid who often do you think professors outsource their review jobs to their grad students. Probably a lot. There is a reason for the term "shit rolls down hill."

Peer review: a flawed process at the heart of science and journals

Peer review: Troubled from the start

Again, and this should be a consistent pattern by now, most of the critiques of the system come from those working within the system. Peer review is probably the best example of this, unfortunately most within the system capitulate to something along the notion of, "It has problems, but it is the best method we have". In this post I challenge that and after reading it I challenge any and all comers to honestly and transparently maintain that it really is the best system available. OPEN SCIENCE smashes the current system to smithereens. It not only answers every question all the time, it answers questions we didn't even know we had!!

Paywall… Really Why Are We Still Having this Conversation?!?: Unlike the free-balling informed speculative hypothesizing I deal in, in order to go out and test hypotheses vigorously it takes a lot of money. You have to travel; see specimens; understand and get access to complex machinery/computer programs etc. etc. It's real work and man hours. Where does this money usually come from? Grants. Where do grants come from? Publicly funded i.e. you and I pay for the research. Which by extension means that since we pay for the research, we should see the research FOR FREE. But guess who hijacks this completely logical sequence of transactions. Those pesky Pay to Play; meagerly reviewed; and unscrupulous scientific journals who often charge up to 40 US$ to get access to one article!?! BOLLOCKS!!

Those jive turkeys at publishing houses will come up with reason X, Y & Z for why they do what they do. Their time is coming to pass. OPEN ACCESS publications are a step in the rich direction but even that modification to a paradigm will quickly become obsolete  under the vastly improved potentialities of OPEN SCIENCE.

Again, I don't want to explicitly define this system just yet - what OPEN SCIENCE means when taken to its logical conclusion - but I do want this idea of what a truly liberal, open, transparent, and inclusive scientific process could mean and how it could be enacted. Just let those two words, open science,  kind of bounce and dance around in your head without judgment, scorn, or ridicule. And just know that as you are reading this the true merits and benefits of OPEN SCIENCE are playing out right now between you, me, and others with or without your permission or acknowledgement.

Blogging Vs. Publishing: Jingmai O'Connor Saga Revisited

"Those who can, publish. Those who can't, blog." Jingmai O'Connor

An unavoidable touchstone that crystalized the blog vs published debate is the saga of Jingmai O' Connor. Brief recap: Mickey Mortimer of theropod database wrote some pieces calling into question some of Jingmai O' Connors conclusions on some stem bird taxonomy. Jingmai really didn't like this post publication peer review (PPPR), and wrote some nasty stuff on FB directed to Mickey. Jingmai deleted her FB response to Mickey but by the power of screen shot those words still live on. Its not my intention to reopen old wounds for some of the people involved but it is necessary back story for the several screeds against blogging that Jingmai subsequently put forth. Probably the most succinct distillation of Jingmai's thoughts are this interview here: If you have valid criticisms, publish them! An interview you should read (as well as the comments) for a refresher or if you are new to the whole incident several quotes of which I will be pulling from.

It was an event that never really came to a consensus or conclusion it just kinda happened and things went back to normal. What normal means basically is that published works and authors just kept on doing what they are doing paying little to no attention to blogging. More or less status quo. No need to cite, reference, or pay heed to blogs.

I firmly believe that Jingmai is a very useful and necessary player in all of this. She said, in no uncertain terms, what I think the vast majority of academics really feel. I applaud her for that, she pulled back the curtain. But that doesn't mean I am not going to take her to task for the things she stipulated about blogging/social media/"amateur hour" and ultimately provide an answer to every problem she details in this interview as well as lay out a rather simple alternative system to the peer review system of which she states:

"But you can't destroy the whole system (unless you have a better one to put in its place) because of a few flaws…. Although the scientific system of peer review is flawed, it is a better system than a free for all of ideas/comments/critiques from netizens of varying education backgrounds."

The destruction of the system will commence and yes, there is a better one.

One of the better points that Jingmai makes, and one I second, is that social media and online "anonymity" have a downside. Everyone has a voice now and they are not afraid to use it, regardless of their educational background or the veracity of their word. What can and does happen online is a sort of  tyranny of the masses, where what we want or expect to be true is often times incongruent with what actually is true. From there a sort of group-think and cognitive dissonance can easily embolden large groups to create us vs. them divisions. The online paleo-community is especially vulnerable to this in my estimation.

How would I suggest that this inherent problem - a savage democracy of science - be dealt with in a system that I am advocating to replace the peer reviewed publication system? Easy. You are not allowed to be anonymous when working within OPEN SCIENCE. What you say and write and put down there follows you… you want to be a 12 year old Jr. paleontologist fine… but say enough dumb shit and your reputation will start to sink faster than the titanic. Words matter in the system I am suggesting. Your words follow you there in OPEN SCIENCE, so probably better for most juniors to just watch, learn, and listen and if you are going to say something best to mind your P's and Q's.

Open Science: Dawning of a New and Exciting Paradigm in Scientific Advancement and Communication

OPEN SCIENCE is already here. The foundation is already laid. All that is needed is the will.



OPEN SCIENCE framework.
What is OPEN SCIENCE?




OPEN SCIENCE would necessitate a central hub, a gathering ground, where anyone can join and become part of the process. You have an account under your real name. Care to venture forth a critique Go for it. Put forth your own hypothesis. Go for it. Such a hub - it would sort of resemble a large forum or something like Reddit - with various subs and specializations would allow delocalized collaboration of science. One party might offer a novel hypothesis. Another party might have the means to test that novel hypothesis. Additionally you might have several parties all simultaneously testing a hypothesis. All the while these parties are showcasing and uploading their work in real time. People can see and read this work in real time and offer real time critiques that can further augment the process. Conclusion derived from the test can be further independently sourced. Maybe a third party that did not do the test or come up with the hypothesis notices something or a line of inquiry that the testers missed… or they noticed a pattern that was missed.

Another source of irritation that I see is when people have relevant work that is not cited or discussed that can be fixed as well in this system because they can see the process happening real time, upload your work, and join in!! Hey check this out, this is relevant!!

Such a hub as I am envisaging it is not really an impossible scenario in fact I would venture that it is happening right now in a more diffuse pattern. We are already seeing large multiple author papers, I'm reminded of that 20 author paper on pterosaurs that Darren Naish talked about on his blog (Dyke, 2014) a bit ago. Pre-print publication is a growing phenomena. I would suggest that blogs, poster presentations, and other such discourses constitute a form of pre-print of putting something out there in order to get feedback. Science happening in real time is already occurring and physics seems to be on the forefront as detailed in this interesting story.  And then there is this: Group of Biologists Bypasses Journals and Uploads Their Work Straight to the Internet. As I keep mentioning there is a new synthesis, a new paradigm occurring in science communication and research; multiple author collaborations; group sourcing; blogging; multiple parallel testing; multiple reviewers; pre-prints; citizen scientists; the disruption of traditional avenues of communication; stewardship; "dropping the curtains"; and breaking the fourth wall. It is all already happening. All I'm saying is that we should streamline the process and put it all under one umbrella.

Are You an Ego Serving Science or is Science Serving Your Ego?

Earlier in this piece I alluded to one central problem that Jingmai O'Connor presciently addressed inherent in the modern paradigm of how science is done: the human ego.



The human ego is a problem for the advancement of science and the human ego is actually the chief stumbling block that stands in the way of a fully operational OPEN SCIENCE paradigm shift. Why is this? Well simply put the human ego is woven into the very fabric of the current paradigm. Who is first author, second author, third author etc. etc.? Who gets quoted in the media? Who gets to be  televised? What "high impact" journal do I get published in? Who gets on the magazine cover? How big and extensive is my C.V.? How much bigger is mine than yours? How many papers did I pump out this year (i.e. publish or perish)?  Who "won the race" towards publication? Who gets the credit? Who gets tenure?

Again these are all problems inherent to the system of academia and the influence of the ego-beast in science and culture at large. Most scientists, like most people in our ego-driven world. are constantly looking for outside validation for internal truths. They need that outside recognition to feed the hole in their heart that they are possibly not good enough. It is an endless cycle to constantly feed the ego-beast. For as much as we feed it, as much as science panders to it, the ego is essentially a human creation. The ego-beast, if you have not noticed, is more dangerous, cunning, and vile than any antediluvian beast I have ever discussed on this blog. The ego-beast holds sway in the whole academic and intellectual enterprise of science. Is it not amazing and ironic that modern science, for all its emphasis on reproducibility, quantifications, and rational discourse, is beholden to something that can not actually be measured, seen, weighed, or that we know for certain is actually a real definable thing?

The human ego will reel at the eternal truths and manifest possibilities of a truly OPEN SCIENCE paradigm shift because such a paradigm shift, in no uncertain terms, takes direct aim at the human ego. There will be victims in such a shift, apart form the more obvious publication peer review system. Because such collaborations as OPEN SCIENCE allows creates the potential for dozens or even hundreds of "authors" collaborating on a piece the cultural construct of the "lead author" conceit bites the dust to a large extent. Because the process is done in complete transparency and openness for the world to see the curtain is lifted creating the "opportunity" for other teams to "steal" ideas and "beat competing" groups to the "finish line". However this really won't be a problem because it will be patently obvious when this is happening. Instead what OPEN SCIENCE promises is the scientific engines revving at maximum capacity and the highest RPMs. Instead of waiting for months or years for a project or study to be published OPEN SCIENCE will speed up this process. The necessary confirming or denying "post" studies can actually be performed in tandem or in parallel at this point. Several independent teams can now test a hypothesis in parallel but complimentary studies to confirm or deny. This creates a faster, more efficient, and collaborative scientific turn over and will dramatically speed up the scientific process. The benefits will become immediately manifest. What might be a tough pill to swallow for some is that notions of "lead authorship", "finishing first", and "beating the competition" become less and less important and will, after some cultural shifting, become transparently ridiculous.

A diminution of the ego-beast, both in science and the world at large, is our calling.

Scientists need to ask themselves, and do some serious soul searching: "Am I an ego serving science?" or, "Is science serving my ego?"

Say it with me, try it on for size: "Am I an ego serving science?" or "Is science serving my ego?"

That will be the crux of the dilemma: the source of the consternation, skepticism, and cognitive dissonance that the scientific community will have to face up to when realizing the manifest potentials of a truly OPEN SCIENCE paradigm shift.

As I keep pointing out the change, the shift, is already happening with or without your acknowledgement or permission. There are already leaders in this paradigm shift away from the ego-beast dominated current science paradigm. Maths "Nobel" prize declined by Russian recluse. Maybe we should all take a page from Grigory Perelman who declined receiving accolades, including 1 million dollars, for his self published work on a mathematical theorem which has confounded mathematicians for over 100 years: the Poincare conjecture.

"Emptiness is everywhere and it can be calculated, which gives us a great opportunity. I know how to control the universe. So tell me, why should I run for a million?" Grigory Perelman

Just let that notion waft through your brain cells a bit. Is the prize of science the external validation? The magazine covers, invitations, speaking engagements, prizes, and accolades? The outside world confirming an internal truth? Or is the process of science, the immersion, the revelation, and the oneness with discovery and the universe the real prize - an internal reward knowable and only felt through the rapture of the pursuit and gaining of knowledge? Tell me which one do you feel is more becoming, more in line with a higher purpose, the magazine cover or the rapture of discovery? Which is reaching for a higher self?

Competition Cooperation and Science Striving for a Higher Self

If we are indeed in an age inculcated with the ego-beast and science is therefore thrall to the ego where can we get a glimpse of how science might work if the ego took a back seat? Can such a situation occur? What might a culture of science look like that did not center on competition, turf wars, politics, publish or perish, huuuuuuge C.V.'s. You know, teh academic cvlt mentality writ large?

There has been such precedence for unfettered and free exchange of scientific information and thought frequencies as documented in the book Innovation in Science and Organizational Renewal (Heinze & Munch). In the chapter "From Salomon's House to Synthesis Centers" (Hackett & Parker) the innovative collaborative strategies of groups such as the National Center for Ecological Analysis and Synthesis (NCEAS) from UCSB are highlighted. These immersive working and living arrangements allow a sort of emotionally laden, fact to face, interdisciplinary and creative process to emerge in order to create new ideas. The caveat is that highly ego-driven participants - those that tend to monopolize and dominate talking time - are not allowed. What occurs at these synthesis centers is a unique sort of push-pull between open and free exchange of ideas and criticism: basically the free form hypothesizing and outside the box thinking coupled with intense "peer review" and criticism. However because this push-pull is occurring in a social setting there is much more profound emotional energy and cadence to the whole process.

From the book (PP 70):


Another group specializing in formulating new ideas and hypotheses, the RA group. actually live on an island together. The RA group as opposed to the NCEAS group actively shuns intense criticism and thought policing during the idea formulation stage.

In the words of one of the participants:


Remember kiddies… these are rational, evidence based scientists laying down more or less a quasi-mystical spiritual experience from their intellectual experiment. Are you brave enough to imagine a sort of scientific process that empowers and emboldens such notions? That far removed from the hyper-competitive, ego driven, slow and stifling process of scientific communication and creation in the current system lays a largely untapped, funner, more collaborative, more efficient, faster, more inclusive, more spiritual and less cumbersome alternative? Just play with these ideas of synthesis centers and unmitigated free thinking and carry them over to the larger online internet community. Can such a diffuse collective brain of the internet, a meta-brain, be already awakening? If you think I'm just getting too far out there I say you are not thinking big enough…

Microelectronics pioneer Carver Mead on the stalled revolution of physics:

"A revolution is when something goes clear around. And what happened during the first 25 years of the 20th century was that there was the beginning of a revolution, and it got stuck about a quarter of the way around."

"What we're living with today is a bunch of mysteries and misconceptions that came about partly because people couldn't imagine nature being as interesting as it really is and partly because a bunch of big egos got in the way and wouldn't let the revolution proceed."

Death of the Iconoclast, Inclusion, and Educational, Financial, and Media Repercussions of an OPEN SCIENCE Paradigm Shift

Death of the Iconoclast

Every scientific sub discipline has its real or self proclaimed iconoclast(s). Depending on who you talk to I myself might be placed in one of these holding boxes. Over here in dinosaur online paleo-weirdo-community we have no lack of such personalities crying foul over the "ivory tower" establishments refusal to acknowledge or entertain their work. My view is probably, not surprisingly, a little bit skewed to the left of what most feel about these characters. Often times buried or hidden amidst the bad or erroneous work of some of these characters are hidden gems that deserve the light of day. Unfortunately because of politics, because of in-group out-group dynamics, because of good guy bad guy dichotomies such gems are often overlooked. In a truly open and free OPEN SCIENCE paradigm such figures whether real or imagined or some combination there of, would hardly get the oxygen needed for such status because everyone can submit their work or even their ideas into the system. Where they can receive not only critique but also help. Sometimes an idea is merely that, an idea that is a bit left of center and can not properly be tested at present. Such ideas should still be archived and kept in the back pocket for future reference.

Inclusion

This might be one of the more controversial and challenging aspects that I will highlight in this piece. It is also a very timely topic in paleontology and STEM sciences in general. No doubt it could warrant its own article but I will include it here because OPEN SCIENCE directly speaks to issues of inclusivity, namely the dearth of females and minority groups in paleontology and science/academia in general. I can anticipate that as many read this they will, sometimes in rapid succession, meet me with both extreme agreement and disagreement regarding my opinions on the matter. I never claimed this was an easy read.

Its Not My Beard Holding You back, Its the System

Yup, this is referencing what you think it is - the bearded ladies project. A social critique of the "bearded, rugged, sweaty, white male" stereotype that many feel stymies entry of females and minorities into the paleontology and potentially academia in general. Now I have to be honest to you about my initial exposure to this project at the Salt Lake City SVP and how it made me feel: ambivalence. Let me parcel this out carefully, I am not doubting or challenging the right for females to express their truths. Their is much to be garnered from how appearances influence reality. How the ubiquity of a certain "appearance" becomes emblematic of that profession and how people not fitting that stereotype will and do face social hardships. I'm not challenging that.

What I can speak to is my truth and that as a; white male; who is bearded; who is large and burly; who is sweaty; who is outdoorsy; and who loves dinosaurs - I felt attacked. Was their something inherent in me, who meets so many of these superficial criteria (OK I don't wear TIVO I wear Patagonia cuz Ventura 805 bitches!), that thwarts others from entering paleontology?!? To add a super thick, greasy, and heavy cheeseburger layer of consternation to this whole thing I myself don't fit into paleontology!?!  I get loads of cold shoulders from people at SVP; I'm not a "real paleontologist" or "scientist"according to many; I'm "just trying to be different"; I obviously detest the modern peer review format and business model; opinion on me amongst the online paleo-community is extremely divisive; "teh workers" ignore my emails all the time; academia and all of it's trappings, don't even get me started… I most assuredly do not fit into paleontology yet someone of my likeness is heralded as "emblematic" of what it takes to be a paleontologist. It's giving me a real conniption fit!!

What I've learned, what is my truth, is that an emotion is there trying to tell you something… so listen!!  Go into the emotion, not away from it. Go deeper. And when I go deeper into the truth of why I feel so ambivalent towards "the bearded ladies project" it is that I too feel alienated, despite my superficial appearance to what a stereotypical paleontologist "looks like", from the paleontological community!

However I've come to the truth that, "I'm not meant to fit into a system that I am here to upend." 

Sexism is certainly a problem, as are gender roles; role models; and subtle social dissuasion. Overall though I see an extremely overt "virtue signaling" appeal amongst paleontology and the sciences to attract and retain females. The issue as I see it goes deeper than the people in paleontology and the stereotype of what it means to look like a paleontologist.  The real elephant in the room, the true barrier that thwarts not just many females but many personality types not amenable to academia is the system itself. Academia is drawn from and retains a patriarchal pedigree. It does not matter how many overtures to females paleontology or other sciences make. It does not matter how many "bearded lady" projects upend gender norms. It does not matter how much virtue signaling we do or shaming of any and all "boys club" type shenanigans occurs. If the system of academia is poisoned from the inside by patriarchy, then you can expect more of the same.

Yes, I did just do that. I called academia a patriarchal establishment and I referred to most overtures towards female and minority inclusion nothing more than virtue signaling. Deal with that seeming contradiction and realize that you will see similar strange bedfellows arise as traditional systems continue to collapse.

Academia promotes:

1) Intense competition for positions and prestige. Ideas are not shared freely for fear of someone stealing. This thwarts and slows science down. Some females may naturally feel comfortable in such an intense environment of competition. Many females and some males may not.

2) Politicking. Yes politics plays and insanely important role in academia. The people above you determine your future, if you get tenure or if you get sent to adjunct professor purgatory. Best not piss anyone above you off, which means you probably don't want to upend any of their theories. This thwarts and slows science down.

3) Non stop working. Want to take a break to have a kid? This could be a dilemma, one hurdle that falls squarely on the shoulders of females. This is unequivocally a patriarchal element of the system and unfairly stymies female progress.

4) My C.V. is bigger than yours!! Can we get any more patriarchal than size comparisons LOLZ? This goes hand and hand with the publish or perish mentality of academia, it is not necessarily the merit of your work but the sheer overflowing abundance of it that counts!?!

5) I made it in the lifeboat why didn't you? This is the attitude espoused by the few that make it to have a successful career in academia. Something must be right with me and wrong with you for me to have received what you can't. Condescending to put it mildly.

6) GROW A THICKER SKIN!! Again patriarchy, emotions are bad blah blah… I take complete offense to this on an internal level because I consider myself a highly sensitive person, and I don't consider my sensitivity a weakness. But if academia is going to make a direct threat to my personhood - what makes me who I am - the gloves are coming off. You can label this under patriarchy and you can confer whatever meanings you like to it if you consider females "inherently" more emotional than men or whatever….

So what if we instead had a system that did not require intense competition but availed the competitive impulse with a more commensal, collaborative process. What if we had a system where politicking was not even necessary but actually tragically passé? What if we had a system that allowed people to take breaks, work remotely, and you know live a life outside of intense academia? That you could leave it and come back to it freely? Where ego, C.V.'s, and impact factors simply did not matter and became transparently bullshite? Instead of stepping on people's heads to get into the lifeboat an immense tidal surge lifted us all to safety and enhanced productivity? Where "growing a thicker skin" was not a prerequisite to having a productive, engaging, and successful intellectual life?

There is a whole army of people that did not finish their phd, that did not come into fruition professionally in academia. Life happened or maybe the cult like trappings of academic politics shook them to their core. The vast majority aspired to join academia for all the right reasons - a calling to learning and the pursuit of knowledge. However what greeted them in academia did not meet these higher aspirations. Academia weeds people out and it is not always the best and brightest that survive the system. These people the system weeded out deserve a voice, they deserve to engage in an intellectual life. OPEN SCIENCE provides this avenue to them. To have a meaningful, engaging, and revelatory investment in intellectual pursuits despite bugging out of a system that did not meet their higher aspirations. A system that failed them and made them feel… less than. This is the ultimate iron, disservice, and crime of our current academic system. It abandons people.

A truly encompassing OPEN SCIENCE paradigm shift could provide these things. It would allow people generally at odds for whatever reasons - culturally, financially, emotionally, biologically - with the current system access to a better one. OPEN SCIENCE will likely be seen as a threat by a certain segment of career academics, as well as it should be. Because it is a threat to how things have been done and how "prestige" is doled out. The inclusivity inherent in OPEN SCIENCE necessarily promotes a shift of intellectual prowess and prestige away from traditional bastions of power and imbues it upon a growing and capable citizenry of science.

Education, Funding, & the Media Within an OPEN SCIENCE Paradigm

Gonna make these parts a quickie because this whole piece is going on for too long already. You know those boring, rote, and cliche things called "academic term papers" that students hate doing and teachers hate reading & grading. They suck right? In fact I would venture they are more about following rules, copying a rubric, and regurgitating information than about actually teaching science. OPEN SCIENCE would make such slavish practises obsolete. Students could instead log into an OPEN SCIENCE hub and immerse themselves in a sub field relevant to their class. Teachers could actively monitor and follow their viewings and comments in OPEN SCIENCE. The student might actually assist in the scientific process!! Way better than another ol' term paper. And hey, if you think term papers are needed to "teach kids to be better science writers" then they should take a science writing course. Your average science instructor is not going to teach jack shit about becoming a better writer anyways. But he/she will ding you for improper formatting of your references… bleagh.

You know how Donald Trump just wants to gut anything to do with science in the US budget? Do you know how a big chunk of Americans are OK with that? Well screw 'em. If it got big enough OPEN SCIENCE could provide a group sourced avenue towards funding research. Maybe its not such a bad thing to get off the government teat as goes research funding.

Bad science reporting anyone? Well OPEN SCIENCE largely puts media out of the loop. People can log in and see science happen real time, not just read some shitty click bait article. Furthermore creators can write multiple versions of their work - highly technical ones as well as more easily digestible ones. Media problem solved.

Somewhere I read that open access solves every problem every time. Well OPEN SCIENCE completely curb stomps open access and answers questions people have not even been asking!!

Worldwide Systems Collapse: OPEN SCIENCE & the Spiritual Revolution

Systems are broke. Things are falling apart.


exert from The Second Coming credit W.B. Yeats

Science is not immune from these depredations. As I have been pointing out throughout this piece many of the most damning indictments against science come from within, from active scientists. That large chunks of the populace have disavowed science or do not completely understand the process of science is reason for fear. However such misgivings are not completely surprising given the failure of the modern system of science to adequately express its merits and techniques.

The way science can get back on track, improve its standing in the world and become the shining light it once promised to be is to complete the revolution. In essence to go full circle back to a time when the spiritual world and science were intertwined.



Keep in mind that Rainn made this before Brexit and Trump, but we can expect more of the same dramatic oscillations. Things fall apart.The center will not hold.

Science no longer has the luxury of not commenting on social, political, and spiritual matters. Those days are gone. Science must find its voice. Science must find its spirit. Part of this process is a diminution of the ego and a policy of transparency and openness that OPEN SCIENCE beckons. Such a simple move on the part of science will do miracles in itself to serve as a template towards diminution of the ego, and increase in transparency and authenticity in other institutions. A disavowal of the ego will give science back its cutting edge - that science can be both a leader in intellectual matters but spiritual ones as well.

"The best lack all conviction, while the worst
Are full of passionate intensity."

It is a bold and brash proposition and one I'm sure I will get push back on. But the alternative is… more of the same.

We do have to try something new. Instead of always condemning a world that is ignorant of science and scientific thinking the science community needs to realize that when you point a finger outwards, three fingers are pointing back at you. It is the scientific community that has; become slavishly beholden to a cryptic method of publication in "peer reviewed journals" rife with obscene profits, inconsistent review processes, and obfuscating language - but worst of all boring; slavishly upholds an academic system based on ego, cutthroat competition, politics, weeding out creative/original people and that perpetuates a patriarchal worldview disharmonious with females and minorities; a system that instead of actively promoting a citizenry of science where those that put in the work and effort can engage in an intellectual life, us vs. them dichotomies abound. None of these problems were created by "those that are ignorant of science" they were created and upheld by those that practice science. Scientists are complicit in this very broken system. A system holding back the floodgates that an OPEN SCIENCE paradigm shift would enact in terms of establishing a robust citizenry of science and unparalleled recognizing of how science actually proceeds, warts and all.

There will of course be challenges and problems in enacting this system, many as yet unforeseen. But the reason number one for resisting a truly all encompassing OPEN SCIENCE paradigm shift is the human ego. And the ego among scientists is huuuge. Putting out your research and ideas in rough form will go against every instinct instilled in many scientists through academia. Many will resist the notion that lead authorship will become an increasingly fragmented and laughable concept. Many will scramble to shore up their ego built castle - made transparently ridiculous that the foundational piece of the modern scientific paradigm, the ego, is inherently nebulous, impossible to measure, and not at all rigorously defined in any certain "scientific terms". Yet we all know that it is there. So if modern science has no problem basing its current system on a completely nebulous concept known as the ego - if science already crossed that road - why not aim for something higher? A more enlightened, authentic higher version of ones self and science.

Spirituality does not equal organized religion. Nor does it equal doing Yoga and shopping at Whole Foods. What I envisage scientific spirituality looking like is nothing dogmatic, nothing decreed from above, but actually a highly personal inward looking subtle acknowledgement of one's being, actions, and thoughts reverberating amongst others and through the cosmos and ultimately bouncing back to you the  creator - not God - but you the creator who has a universe within.

This is, after all, not disharmonious with what science is actually telling us about our relationship to the universe. And hey, you can do a lot worse amiright?


This is the dawning….
of the ago of aquarius

*special thanks Anneke van Giersbergen & Devin Townsend

"A Long habit of not thinking a thing wrong, gives it a superficial appearance of being right, and raises at first a formidable outcry in defense of custom". Thomas Paine