#theropod lips

[ildarotyrannus]

The sketches in sketchbook with toned paper. :) It's baryonychine (speculative reconstruction with "lips") and Spinosaurus, both done without references. In the process, I used a white pencil (I have hardly used it so far) for the light parts, it turned out to be a very good volume.

Black ballpoint pen, white pencil and gouache (for minor corrections), 2024.

[dinofigureoftheday]

Dino figure of the day: Eofauna Tyrannosaurus rex "Sue"

[howtodrawyourdragon]

Dinovember 2023 Day 1:

Saltriovenator // Tiger

Obviously, I'm not an accurate Paleoartist, but I tried my best. Side view because I have every little experience drawing dinosaurs.

-XOXOX-

Please don't repost or use any AI on my art. Thank you.

[prehistoricpencil]

New paper supporting lipped theropods was just released!

They looked at the wear patterns on the enamel of a crocodile tooth and a daspletosaurus, as well as the skull length/tooth height relationship for multiple theropods and monitor lizards.

The crocodile tooth had more wear on its exposed side, while the daspletosaurus tooth had similar enamel thickness on both sides, indicating that they were likely covered by soft tissue, which keeps enamel moist and resistant to wear. They also found that theropods did not have a larger relative tooth size than monitor lizards do - the largest teeth belonged to the crocodile monitor, which has extensive soft tissue covering its teeth. This means that even Tyrannosaurus could plausibly have had their teeth completely covered by lips despite their size.

[fr-thrice]

wildclaws may not have correct theropod wrists but at least they have lips over their teeth, ahead of their time with that one

[mountmultimuses]

More Dino Art

Tyrannosaurus Rex (closed mouth)

[datgreenmonstah]

More things that I left out because tumblr has an image limit

While the mechanoreceptors/trigeminal nerves in alligators as well as crocodilians are very similar to T. Rex there is still the lacking of lips to protect the enamel of their teeth.

Mechanoreceptors in alligator face

The rostral neurovascular canals of Tyrannosaurus rex (FMNH PR 2081) in lateral view (top) and two cross-sections (CT slices, bottom). Scale bar equals 30cm.

This is where waterfowl come in as not only do they share similar trigeminal nerves and mechanoreceptors that both alligators and theropods have.

The morphology and distribution of cutaneous mechanoreceptors in bill and tongue of the mallard(upper and lower bill)

They also have skin that acts like a lip, hanging from the edge of the mandible and hanging over the lamellae as if they were teeth.

Preserved pecking duck head showing where the bone ends and the skin hanging below begins.(first) male wood duck with mouth open showin how the upper bills lamellae are hidden(second)

In comparison to reptiles that lack these intricate mechanoreceptors that not only run through the skin of the animals, but also inside the bones of the nasal and mandibular cavities.

Only having a papillae attached to the receptor on or near the edge of individual scales and the nerves they attach to only being skin deep in comparison to archosaurians like alligators, theropods, and waterfowl.

The skin sense organ of some iguanian lizards

If the lack of formina for corpuscles/trigeminal nerves/mechanoreceptors on the mandibles of reptilians outside of the ones that run along the lips isn’t enough, hopefully seeing the neural pathways in both alligators and waterfowl and comparing them helps.

Theropod Facial structure theory

I have been trying to write this paper out so many times and the lack of funds to hire an editor/publish as well as getting this organized in a fashion that's considered proper for a scientific paper has caused me to hit so many walls, not including the learning disabilities that have made this worse to get this out. So i'm doing this to get what information i've been gathering since 2018.

looking at young corvid images of their open mouth, they had a lip area in their mouth that the upper beak would overlap and lay in perfectly, this is what started me down the road along with noticing the formina on the sides of theropod faces matched that of goose skulls I saw online. As I had no access to actual specimens in person.

feeling as though waterfowl specimens were the easiest to obtain(they were actually more difficult than thought) as well as being closer to dinosaurs on the evolutionary tree next to ratites, and even living along dinosaurs during the late cretaceous ie presbyornis, they seemed to be the best to study for this.

After obtaining a pair of peking duck and an african goose, from some local farmers that donated them, they were dissected and preserved using techniques learned from taxidermy for study. The specimens had one side of their bills removed while leaving the skin intact on the otherside. One of the peking ducks kept the tissue on both sides, while only one side had the top layer of the epidermis removed, exposing the harder dermis underneath. A noticeable attribute was that before preservation the bills were plump and didn't show any texturing, except for the goose around the back nearest to the corner of the mouth. Once preserved however, the skin on the bills shrank, revealing grooves and texturing where nerves and blood vessels would run.

The sensory organs and nerves that ran in the bills were observed using a candlelight method/ie holding them up to the light.

Tyrannosaurus Juvenile Jane specimen for comparison

The deep grooves and formina on the bill, as well as the formina and grooves that are seen in T.Rex have many similarities, which was the main focus of this study as they're are numerous studies pertaining to their sensory organs. Also something to compare is that there is a distinct row of formina that's more prominent on older crocodiles and alligators along the dentiary similar to that of T.Rex, on both the top and bottom row of the mandibles.

saltwater crocodile head from crocodiledarwin.com and alligator from encyclopediaofarkansas.net

komodo dragon profile view(comparing formina)

Though waterfowl having lamillae cannot be used to compare enamel ware. While crocodiles and alligators have teeth, but are known for not having lips, have ware and tare on their teeth than animals like monitor lizards that have lips as shown in this study using a relative of Tyrannosaurus rex to prove they had some form of lip to protect their tooth enamel.

Another observation is that in alligators the bottom row of dentary is tucked under the upper mandible and covered more than in crocodilians. It would be interesting to see the tooth study done with other teeth on both animals, as some of the posterior dentary on the upper mandible can sometimes be seen tucking away in a pocket of skin as protection in some alligators.

Also looking at neonatal alligators shows a depression in the lower jaw area that the upper dentary could sit in, almost as though their reminants of lips

neonatal alligator from natgeo on alligator facial mechanoreceptors

and while alligators and crocodilians seem to have scaling on their face this is just thickened sensitive skin with cracked texturing imitating scales. Bills on waterfowl are also thickened as this allows them to forage in merky waters and plants without damaging their bills. While both animals have thickened skin on their manidbles, it is still a very sensitive part of their body that they use to navigate and explore/manipulate their environment as well as interact with other of their species. While reptiles have less sensitivity and do not share these organs along their faces(the skin sense organ of some iguanian lizards). This could be also a lack of information on the anatomy of reptile skulls and facial structures that could be expanded more for comparison.

However there was a study done on the facial sensitivity of Tyrannosaurus along with alligators

See Complex Neurovascular system in the dentary of Tyrannosaurus

See Despite their thick skins, alligators and crocodiles are surprisingly touchy

and while it took awhile to find and make available, there had been a paper written on a very similar organ within the bills of waterfowl, namely mallard ducks.

See The Morphology and Distribution of Cutaneous Mechanoreceptors(Herbst and Grandry Corpuscles in Bill and Tongue of the Mallard)

And while Monitor lizards and other reptiles share a similar formina pattern, they lack the textured grooves and sensitive organs archosaurs and certain avians share, as well as other anatomical features of moniotor lizard skulls that they share more closely with other reptiles and snakes than they do with the archosaurians and avians.

komodo dragon skull ventral view

Alligator(left) Crocodile(right) ventral views of skulls

Peking Duck skull with bill skin(ventral view)

T.Rex skull ventral view

another observation in many reptile skulls is how the upper and lower dentary interact. While some had teeth that overlapped the lower mandible, there seemed to be somewhere that the teeth met, either at the anterior end of the skull or continually all around, in monitors there was some sort of gap at the anterior portion of the dentary to make way for the tongue to be able to slide in and out without being obstructed too much while allowing the mouth to stay closed. Where as archosaurs and avians the two overlapped one another allowing for a scissoring affect with the teeth, the most noticeable being the anterior end of the mandibles. And while waterfowl lack the dentary that archosaurs and reptiles have, the lamillae still slide past one another similar to what's observed in many theropods, even in non avian dinosaurs. The thought of bone to tooth contact is considered as well, and there can be a sizeable closure without the need for the amount of soft tissue observed in reptiles.

proposed crocodilian like contact of tooth on mandible(top), proposed soft tissue similar to that of monitor lizards(bottom left), new proposed soft tissue without scaled lips(bottom right)

Having soft tissued lips that is similar to that of a waterfowls bill allows for the mechanosensory corpusicules to interact as well as still allows for protection of the tooth enamel.

The way their upper dentary line up with their lower mandibular formina seems to follow the same pattern, compared to reptiles that didn't curve upwards towards the anterior portion of the lower mandible. There's also a possibility of having a nail, like waterfowl, or some large scale, like many other reptiles with dentary, at the anterior ends of the upper and lower manible. This is due to the amount of formina clustering in a pattern like structure similarly seen in both waterfowl and reptiles.

These observations and studies allowed for an idea of how to reconstruct Tyrannosaurus Rex

Juvenile Jane Tyannosaurus Rex skull, with open and closed mouth(top) and reconstructions

Even constructing a physical reconstruction to better observe how the lips and teeth would interact.

Paper mache head reconsturction done in a similar manner to the duck and goose specimens used in this study

Also when reconstructing, and also accounting for tooth slippage, there was an issue with a sizable gap at the anterior end with the front dentary when closing the jaws when attempting to imitate the mouth closing similar to that of previous reconstructions using reptile lips, where as with the more waterfowl skin reconstruction there was less of an issue and also less of an overhanging bottom lip.

Pages from personal study notes

There was also the issue of either exposing the jaw muscles similar to how crocodilians, alligators, and other reptiles are observed to have, or to cover it in skin like birds. One of the arguments is that the mouth wouldn't be able to open to the extent allosaurians and tyrannosaurus are able to open their mouths. When there are several avian species with skin over the area that can very well open their mouths just as wide, ie Bell Birds, which have a widened jugal bone like that of tyrannosaurus.

Young tyrannosaurus specimen(chomper)

Also to note, in most reconstructions where there is a bony knob on the jugal, circled in the above example, is more than likely a muscle attachment point, and the divet in the space before the attachment point could allow for the corner of the lips to sit.

In conclusion, Tyrannosaurus Rex and possible other theropod dinosaurs with similar skull anatomy of the upper and lower mandibles more than likely had thickened yet sensitive skin with a lip like structure similar to that of waterfowl and not a scaled skin.

Additional research papers on duck bill anatomy/mechanreceptors

Histomorphogenesis of Upper Beak in Muscovy Ducks (Cairina moschata)

3D architecture and a bicellular mechanism of touch detection in mechanosensory corpuscle

Molecular basis of tactile specialization in the duck bill

Personal Notes on research

[wingedwoif94]

Highly speculative Spinosaurus paleoart! There's a lot going on here, I tried to take into account its ecological niche of being a river walking fish eater. Sort of stork or heron-like. I don't see much of a need to blend in being such a massive and niche animal. So I based the coloration on some semi aquatic birds. I increased the size of the head crest by a lot because I ADORE the idea of large theropods with bird-like crests and combs. Honestly I think it could have been even more extravagant for sexual selection, but who knows. I also covered parts of the "beak" with a hard covering that extends up the face and onto the crest. And added lips because I feel like that just makes sense with how the skull looks. But I'm not a paleontologist so!! Who knows!! Big duck!

[i-draws-dinosaurs]

What do you think about the walking with dinosaur trex? As a kid I always thought the head looked really boxy, it looks very distinct from other trexes I’ve seen around.

Walking With Dinosaurs Tyrannosaurus is,,,, Bad

I'm not sure what it is about WWD and large theropods but both the Tyrannosaurus and Allosaurus look really Weird, especially in the head. Allosaurus's horns got placed directly over its eyes, and the whole shape of the head is really triangular.

With the Tyrannosaurus, the head is just. a Block.

Proportionally it's shorter and thicker than a real Tyrannosaurus skull, and while the shape of the lower jaw is actually pretty close the back of the skull is where issues really start to crop up.

They've ticked all the boxes in the abstract: big brow ridges, wide back of the skull, heavy lower jaw. But the execution of them really falls flat. Mark Witton's reconstruction from the recent theropod lips paper actually makes a very good comparison here since it's almost at the same angle:

The body itself is oddly proportioned too, with very long legs, and shorter thinner tail, long arms, and a thin neck. Overlaying Scott Hartman's Tyrannosaurus skeletal over the top of it really brings out the Weirdness

In some areas, like with all of WWD, the inaccuracies here are due to Science Marching On (the lack of lips and the shallower torso due to differently-reconstructed gastralia). But most of the problems with how the head is shaped were just at inaccurate in 1999 as they are now, and it's a little baffling to me how such a famous and well-studied dinosaur ended up looking so... Off?

On the other hand, the actual behaviour of the Tyrannosaurus is fantastically naturalistic, and the colour pattern is very appealing and absolutely iconic. It's just kind of a shame that it got combined with this odd, lumpy anatomy

[paleonativeart]

Day 3: Camouflage

A basal crocodylomorph Hesperosuchus agilis is hidden in a paleo-ferns to avoid predators such as other basal theropods.

Speaking of which, resent studies that hesperosuchus suggested a possibility extistence of lepidosaur-like lips that protected its teeth from the outside, like theropods have.

[ildarotyrannus]

The portrait of the abelisaurid theropod Abelisaurus comahuensis that I made last year. I tried to work in a style like acrylic paints, but with monochrome. I like some aspects of this work, such as the eye and the keratin around it, but it's clear from the skin folds and facial scales that I have a lot to learn. I hope to do a remake of this in the future, but in a slightly different style. Done in Paint Tool Sai 2.0.

[thesumlax]

I thought I was done with the dinosaur stuff for now but I keep reading more and thinking more and doubting my conclusions again.

So I drew this Heterodontosaurus to show all the possible mouths I believe dinosaurs could have. The "carnivorous lizard" model would clearly be ancestral and retained in typical theropods (and maybe Heterodontosaurus itself is basal enough to still have it), "herbivorous lizard" makes sense for sauropods, and "bird" is for theropods with fully beaked toothless jaws - like birds. Ornithischians, though, are a bit complicated. They have beaks, but not like birds, and their inset tooth rows are kinda like a more extreme version of what we see in lizards like Uromastyx... Not to mention that more derived ones, like ceratopsids, have these weird giant jaw muscles. I tried a similar approach with my drawing of Chasmosaurus:

The "herbivorous lizard" looks weird (which may be just because it's a quick edit of a picture that wasn't intended for it), but the condor-like "bird" suddenly breathes new life into the cheek concept I've been trying to refute... but that's all assuming that Nabavizadeh's muscle reconstruction is correct in the first place. Maybe I should read his Illustrated Guide to Dinosaur Feeding Biology if my depression lets me.

Also, almost forgot - the beak thing. I've depicted versions of Heterodontosaurus beak both uncovered and covered by a Trionyx-like lip. While the beak doesn't really need covering, the teeth above it probably do.

[harpagornis]

Did phytosaurs have lips?

Mystriosuchus planirostris by @paleoart, the inspiration for this post.

2016 was many things, but one of the best was definitely being the call out year for many archaic paleoartist mistakes. One of these was the absence of lips in many reconstructions, from the skin-wrapped maws of theropod dinosaurs to the bare-toothed saber-toothed cats to the rather ridiculous depictions of entelodonts and other prehistoric mammals as fanged demons. This year saw the publication of various papers showing that teeth do generally in fact need lips to be protected from damage and moistened, meaning that many animals traditionally reconstructed as bared-toothed monsters need a healthy amount of oral tissue.

That said, things aren’t black and white. Crocodilians, after all, still have bare teeth. In one of these papers, Larson et al 2016, it’s been suggested that their aquatic habits compensate for their lack of lips, as humidity certainly isn’t a problem. However, as the Mark Witton link above informs you, many crocodiles go through prolonged periods of life on land without tooth degradation. It also doesn’t cover how terrestrial crocodylomorphs would have coped with the absence of lips, or why many aquatic vertebrates like dolphins (Platanista aside) still kept their lips.

It seems, therefore, that crocodiles are simply off in this regard. Their liplessness actually appears to derived from a highly unusual facial development process, which essentially renders their entire face a single “scale”. This seems to have evolved in order to develop the extensive Integrumentary Sense Organs (ISOs), thinning the facial skin in order to increase sensivity, and it carried over into their terrestrial descendants.

This obviously raises the question of whereas groups similar ecologically and morphologically to aquatic crocodilians underwent a similar process. Where they also lipless, or did they in fact retain their lips, making comparisons to crocodiles all the more questionable?

The Phytosaurs

​

Phytosaur head diversity by Darren Naish. Taxa included: Smilosuchus gregorii, Pravusuchus hortus, Mystriosuchus westphali, Paleorhinus bransoni and Pseudopalatus pristinus.

Phytosaurs were, in some respects, the “original crocodiles”, having evolved and prospered long before crocodylomorphs ever touched the water. Although they weren’t particularly closely related (birds are closer to crocodiles than phytosaurs are), these archosauriform reptiles did hit most of the same notes as crocodiles: barrel-shaped bodies, extensive osteoderm armours (in some cases even better protected, due to the bell-shaped cap on the throat and various scutes on the forelimbs and belly), generally short limbs and large, paddle-like tails.

While some phytosaurs explored odd ecological niches – Nicrosaurus and similar taxa are adapted to a primarily terrestrial lifestyle,  while Mystriosuchus was inversely so specialised to life in the water that it was practically the Triassic Metriorhynchus -, a generally semi-aquatic lifestyle for most phytosaurs can be inferred due to due sheer prevalence in freshwater and shallow marine deposits, limb proportions and shape, laterally flattened and powerful tails and retracted nostrils (though keep reading).

Various tracts attributed to these animals similarly imply a close functional match between phytosaurs and crocodiles. Various swimming tracts have been attributed to phytosaurs, while the Apatopus footprints show an interesting insight on these animals’ terrestrial locomotion capacities, being capable of an erect gait like archosaurs and mammals, including modern crocodiles and alligators. Paleopathology studies indicate similar behaviours such as interspecific biting (hence the need for strong armour), and perhaps more damningly endocast studies show that the general phytosaur brain shape was rather similar to that of modern crocodilians (albeit with a few differences, like the size of the brain and the presence of multiple sinuses; see below).

For all intents and purposes, phytosaurs were functionally crocodilian, offering one of the most extreme cases of convergent evolution ever recorded. But no matter how close, phytosaurs were still off the mark in various ways.

Phytosaur facial anatomy and morphology

Pseudopalatus buceros skulls, exemplifying the general morphology of phytosaur skulls as well as interspecific variation. Notice massive premaxila.

The most classical thing you’ve ever heard about phytosaurs was how they differ from crocodiles in having the nostrils be close to the eyes/on top of the head rather than at the tip of the snout. This is true; as you can see, the nostrils are located in front or above the eyes in a “volcano-like” elevation; combined with the nostril-less and often conical snouts, this gives them a distinctive dolphin-like profile.

Like in cetaceans, this nostril placement would come in handy on a mostly aquatic lifestyle, avoiding drag and allowing the animal to surface only a small part of the head and remain concealed underwater. However, unlike cetaceans – and marine reptiles such as plesiosaurs -, this nostril position is not derived from nasal retraction. In fact, phytosaur nostrils are sometimes noted as being rather protracted, sometimes as a result of the general elevation of the nasal region.

Instead, what happened is that phytosaurs elongated the premaxila at the expense of the other skull bones. Unlike crocodiles – and whales and plesiosaurs and many other aquatic tetrapods -, half or more of the phytosaur upper jaw is composed of a single bone, normally a vestige at the end of the jaw in most amniotes, that expanded radically. This hints at a pretty rapid elongation of the snout, explaining maybe why long-snouted phytosaurs appear “out of nowhere” in the fossil reccord.

Predictably, this could also hint at rather atypical development, which is etremely important in dictating the presence or absence of lips.

Another frequently cited difference is the presence of antorbital fenestrae. These are the famous “holes” in front of the eyes present in most dinosaurs and other archosauriform reptiles. Crocodiles have lost them, but they are present in phytosaurs, though they can be reduced in some species. Perhaps associated with this, phytosaurs also have extensive antorbital sinuses, while crocodilians lack them altogether. Phytosaurs also have an extensive premaxillary sinus, though as crocodilians have most of their snout taken by the nasal airways this may not make a lot of difference.

With a few exceptions, most aquatic crocodilians have conical teeth; they compensate for the lack of meat-cutting speciations with the infamous “death-rolls”. Phytosaurs, by contrast, generally have serrated teeth, and combined with the presence of crests on many specimens it seems unlikely that these animals engaged in “death-rolls”, instead opting for more typical meat-eating behaviours. To date longirostrine phytosaurs are the only “gharial-like” vertebrates with serrated teeth, and it might explain why they were frequently associated with the carcasses of terrestrial vertebrates like rhynchocephalians and dinosaurs.

Unlike the teeth of crocodiles, phytosaur teeth seem to be rarely interlocked. Even without lips, it seems likely that the upper jaw teeth covered the lower jaw ones.

What about the lips?

​

Leptosuchus skull, illustrating the basic points for and against phytosaur lips. For are in red: anteorbital fenestra and serrated teeth. Against are in green: long prexmaxila, POSSIBLE ISOs, front teeth POSSIBLY too large to fit within lips. The latter two are of course ambiguous.

With the above in mind, the absence for or against phytosaurian lips is…mixed.

The rapid premaxilary development in phytosaurs is the key to understanding how the jaw integument of these animals worked. It is possible that the premaxila’s growth prevented the formation of conventional lips, either due to physical and metabolic constraints or because the same genes triggering it could have prevented the development of lips. Perhaps the same pressures causing the crocodilian “single scale” would have been forced on phytosaurs by this developmental quirk.

On the other hand, other parts of the phytosaur skull anatomy seem to suggest the presence of lips:

The aforementioned antorbital fenestrae suggests that the phytosaur skull was less “skin-tight” than that of crocodilians. In modern birds, the only living reptiles with antorbital fenestrae, that area of the skull is covered by various soft tissues, and indeed areas of the avian beak devoid of a rhamphotheca tend to be covered by fleshy lips.

Serrated teeth tend to be more vulnerable than conical teeth to degradation, so most predatory animals that possess them have them covered by lips. The only crocodilians with clearly serrated teeth are terrestrial species and the fairly basal thalattosuchians, which are still on the limbo on whereas they had lips or not.

It is possible that phytosaurs found themselves in an unique integumental arrangement. Perhaps they did become lipless, with a “single scale” covering the jaws, while the rest of the head had a more normal integument.

A deciding factor in this argument would be the discovery of ISOs on phytosaur jaws. However, structures associated with these organs, such as pits, are rarely discussed outside of the context of pathology when it comes to these animals. There is plenty of literature on pits and holes in phytosaur skulls being caused by fights and bites, but few on any possible natural ones.

Conclusion

​

Modern Ganges River Dolphin. Although it has exposed teeth, it’s also not the norm among cetaceans.

Just because something resembles another doesn’t mean that there is an exact equivalency. Case in point: no matter how close phytosaurs got to crocodilians, they still differed in many aspects, and could not be mistaken for them in life.

It’s clear that skin-wrapping is a tremendous lack of appreciation for the organic nature of extinct animals. The lack of lips in crocodilians has been taken far too long to be the “norm”; but, as it turns out, it is an anomaly among the usual amniote tendencies.

We may never know for sure whereas phytosaurs had lips or not. Hell, it’s even possible that some had while others went full Platanista. However, far too often are they taken to be crocodile-like for granted, without other possibilities, equally as valid as they are, taking into consideration.

Hopefully, further research will grant us insights on how these already spectacular animals looked in life.

References:

Reisz, R. R. & Larson, D. (2016) Dental anatomy and skull length to tooth size rations support the hypothesis that theropod dinosaurs had lips. 2016 Canadian Society of Vertebrate Paleontology Conference Abstracts, 64-65.

Grigg, G., & Kirshner, D. (2015). Biology and evolution of crocodylians. Csiro Publishing.

Soares, D. (2002). Neurology: an ancient sensory organ in crocodilians. Nature, 417(6886), 241-242.

Stocker, M. R. & Butler, R. J. 2013. Phytosauria. Geological Society, London, Special Publications 379, 91-117.

Kimmig, J. 2013. Possible secondarily terrestrial lifestyle in the European phytosaur Nicrosaurus kapfii (Late Triassic, Norian): a preliminary study. Bulletin of the New Mexico Museum of Natural History and Science 61, 306-312.

Gozzi, E. & Renesto, S.A. 2003. Complete specimen of Mystriosuchus (Reptilia, Phytosauria) from the Norian (Late Triassic) of Lombardy (Northern Italy). Rivista Italiana Di Paleontologia e Stratigrafia 109(3): 475-498.

Michelle R. Stoker; Sterling J. Nesbitt; Li-Jun Zhao; Xiao-Chun Wu; Chun Li (2016). “Mosaic evolution in Phytosauria: the origin of long-snouted morphologies based on a complete skeleton of a phytosaur from the Middle Triassic of China”. Society of Vertebrate Paleontology 76th Annual Meeting Program & Abstracts: 232.

[biomecharnotaurus]

YOU! DINOSAUR FUN FACTS OR FACTS ABOUT YOUR DRAGON-SONA!!! NOW!!! (so so lighthearted but please please feel free to write as much as you like, your mind is so so swag)

AAAH THANK YOU I'LL GO WITH BOTH >:) ❤️❤️

Random dinosaur facts:

Stan the T.Rex is the most brutally injured male tyrannosaurus specimen we currently have public access to. His neck was broken off by another t. rex, so was part of his jaw and skull, but all of these injuries healed back at the point of him reaching adulthood. We even found a tooth that pierced through his brain still inside of his skull and he very likely had to live through all of his life in pain (the bones didn't heal exactly right). He is the confirmation that these animals were stupidly strong and resilient.

There is a probability that the spinosaurus is a chimera of different species of theropod we just mixed together, because its current anatomy doesn't make much sense. Its legs are too short for its weight, it's built like it should swim but its hydrodynamics are awful (its finned tail didn't have muscles and bones made to swim like in the case of the tails of modern crocodilians) and we are still not sure what was the purpose of its sail. Also, the specimen we currently have was literally bombed during WWII 👍🏻

Ceratopsidae dinosaurs (the family of triceratops) didn't have cheeks. And they had actual reptile-like "paws" with fingers, not elephant meat-mittens. Also, most of them were murderous tanks

Non-avian theropods had lips that covered all of their teeth when closed, kinda like monitor lizards.

Cyrav facts:

He has both mammal and reptile traits. He has dog-like ears, lion-like teeth, theropod legs, scales, feathers and osteoderms. Warm blooded.

He is technically a very stylized eastern dragon with some western dragon traits.

He has a swordfish nose-horn and he uses it pretty much the same way.

He has a scorpion-like tip of the tail.

Color choices and multiple eyes are a reference to ophanims/thrones.

He technically should have antlers to resemble the Tree of Life.

He can "summon" bird-like wings like some eastern dragons.

He also has cat-like whiskers, other than the catfish-like ones.

[a-dinosaur-a-day]

Would beaks on some theropods explain the exposed teeth problem with early reconstructions better or about the same as jowls or just lips?

I mean, that's my hypothesis if I'm being completely honest, that they have beaks instead of lips or jowls in most cases

[vees-strangeworld-omniverse]

ARGONUS INFO: the Elkinets, an "advanced" guide

(NOTE: description copy-pasted from DA where i normally post my works. any context that is missing here on tumblr can be found on my DA [linked here and on pinned post] )

[this is a single image best view if opened in a new tab. the top image was the first formal post about them, before i actually started my argonus worldbuilding series]

[re-uploaded due to original being posted from main]

[tumblr edit: this guide is meant to be a "basic" guide to the elkinets themselves. obviously, because they represent airplanes and airplane-like drones, they come in such a wide variety. also, idk how the formatting is, so excuse any issues and mistakes. i also edited some grammar issues as well. ]

GENERAL BASICS elkinets, on the surface, look like your everyday generic aeromorph, that is a living aircraft with a humanoid shape (a rather "basic" one at that).

they have a clearly defined head, neck, body and tail. they stand on two legs, and the wings act as arms and hands when not used for flight. however, there are some things that separate them from other similar aeromorphs.

-excluding the engines (Later on that), they and the other aeronoids both have an entirely biological existence and an evolutionary background, being highly derived from argonus's early Psittacopasserae birds (parrots and passeriformes) during the late paleocene.

-the legs and feet aren't landing gear, rather they are much like that of birds and theropods, further reflecting on their evolutionary past.

-their skin is soft and leathery, not unlike that of a human's (kinda creepy, but whatever) it is, however, comparably the same thickness as our own.

-their cockpit / canopy / windows are purely aesthetic, having no real function. it is solid in color and made of skin like the rest of the body (they are often called "canopy/window integument")

-they have a skeletal structure not unlike other tetrapod's, alongside organs as well.

-there exist a dwarf / pygmy version of them, which occurs when there is a lack of natural resources.

 now that's established some of the basics, we can get into the specifics of it. BODY SYSTEMS      being a tetrapod, they have various organ functions, though here are listed some of the important one:

SKELETON: the skeleton of an elkinet is still similar to birds, but there are a few highly-derived parts of it. two major examples are the skull and arms.     much of the skin covers the head like it would with the skull. it has lips to cover the "teeth", keeping them lubricated with saliva. these "teeth" aren't actually true teeth despite initial appearances. they are instead tomium (what geese have) that have the same function as canines, premolars and molars, covered in the same material as the beak. their incisors, however, are what's left of the actual beak they once had. both the beak and teeth constantly are growing, and while the process of mastication (chewing/grinding of the teeth) is often enough to keep them trimmed down, proper dental care is still required.     the arms are also very derived from the original animal. everything is normal right up to the metacarpals, where we see the metacarpals small and atrophied. the metacarpal isn't completely useless, since it (alongside some cartilage) help anchor down the many muscles that make up the other half of the arm.      just like modern birds, the bones are hollow. this allows them to stay relatively light in weight so they can much easily fly, but does raise the risk of injuring those bones. this is especially a problem with older, larger individuals.

MUSCLES: an elkinet's strength varies from aircraft to aircraft, but in any case they are pretty muscular regardless.     the area with the most muscles are the half end of their wings. these muscles help move and control the rest of the wings, but more importantly they help manipulate objects. this is, obviously, because they have no fingers, so having those muscles are really useful for delicate task like writing.     their legs are also pretty muscular, which is a given since they use them for getting around on the ground as well as taking off and landing.      the tail stabilizers, canards and prop blades can also move around. those parts can move in a similar fashion to the wings, though more weaker and are often used as more of displaying emotions.

RESPIRATORY AND CIRCULATORY: while two different body systems, they go hand and hand together.      -respiratory- the elkinets have a strong respiratory system. their lungs are large, having various air sacks to help with gas exchange. in addition, elkinets have re-evolves diaphragms. elkinets primarily breath through their nostrils, which can sometimes hide behind the engine intake if said engine is on the face.     -circulatory- elkinets have a four-chambered heart, not unlike any other tetrapod. their blood is red, and so is a fresh wound. however, said wound then turns grey during the healing process (unless injury is permanent, then it stays gray). apart from where you'd usually find mass amounts of blood flow, the engines are also a major place for blood to go through, especially if being used in flight.     the engines is always loosely connected to both circulatory and respiratory systems. when running, the engines can take in oxygen and puts it into the bloodstream. this is, however, not super effective since it only takes in 1/10 the amount than the lungs.

DIGESTION: contrary to what one may think, elkinets do not consume jet fuel, nor any kind of fuel, rather they eat actual food.     elkinest are, for the most part, just as omnivorous as we are. they are capable of consuming both plants and meat, and have been domesticating animals and plants for food for many, many centuries. however, exactly which one they consume the most can vary. for example, larger aircraft may stick to a more vegetarian / vegan diet because plants are far more easier to produce and yield more food than animals. on the otherhand, some places don't have much land for growing crops, so they stick to eating mostly animals. and, of course, we cant forget about the various cultures and what they eat as well.     since the elkinets have the tomium to help grind down food, they have de-evolved their gizzards as they serve no real purpose anymore. they do, however, still have a cloaca, the single hole on their butt that used for everything down their (waste + reproduction).

REPRODUCTION: i won't dwell on this too long since i don't like talking about it. all you need to know is that while their cloaca conceals their reproductive parts, they still have the usual reproduction organ that most other tetrapods have. they also lay eggs, like birds

PHYSICAL APPEARANCES & ANATOMY

now we head to the rest of the body and their physical appearances.

HEAD:     like said with the skeleton, elkinets have a reduced beak that act as incisors while the tomium act as the rest of the teeth. but apart from that, what else is going on?

-canopy/cockpit: like said in the beginning, the canopy has zero function, at least by our terms. they do, however, serve as identifying features between individuals. the color of it will vary; most of the time it's some shade / hue of blue, but it can also be any color. the canopies' color always stands out from the rest of the rest of the body.

-eyes: eyes are rather human-like in shape, but the general style of them can vary. regardless, elkinets always have a clearly defined pupil and iris. and they come in a wide variety of colors (another way of identifying individuals). in very rare instances with trainer aircraft (particularly ones with separate canopies), the elkinet may have four eyes, much like the other argonian fauna. it's unclear why it's specific to trainer aircraft and not other kinds.

-ears: the one thing that remains consitant with the rest of argonian vertbrates are their ears; they have four earholes, which are covered by a flap of skin akin to an earlobe. they are desgined to protect their hearing durring flight.

-fangs: sometimes the canine part of the tomium can stick out of the mouth. these are usually small and dont create much of an issue.

NECK & BODY     all elkinets have a neck, however short they may be. the neck and spine are very flexible, and the neck can turn a near 180 degrees. when standing, the body creates and S-like shape. although they may look top-heavy, they're center of gravity is actually around the pelvic region (Often helped with the tail), so they don't constantly fall over.

ARMS / WINGS     the "hand" part of the wing is called the "paw", and in spite of it's shape it is extremely dexterous. alongside the muscles at the wingtips that control the appendage, the paw's underside (their "palms" so to speak) are as soft and sensitive as our fingers. the palms, as well as the underside of the paw in general, are also covered in setae (same stuff some geckos have), which they can control to hold / drop items. this allows them to hold smaller objects without moving much of the wingtip's' muscles.     the length of the arm, regardless of aircraft, is always long enough to do basic arm stuff (grab, stretch etc.). they are also never past the neck of the elkinet, and are always directly connected to the body around the chest /abdomen area. in the multiplanes (biplanes, quadplanes, ect), there are no support beams between the wings, and as expected those extra wings will also function as arms.

LEGS AND FEET    the legs of the elkinet are directly underneath the wings. although no longer needing to live in the trees like their passeriform relatives, most elkinet feet still are still capable of and used for perching and grabbing onto stuff. with some of the longer-winged aircraft, there comes longer legs to keep the wings from dragging onto the ground. the colors of the legs are always greyish in color, though can have a little tint to them. there are five major feet types when it comes to variations:

-standard anisodactyl: one of the most common leg types, all aircraft can be born with anisodactyl feet. these kinds of feet are not exclusive to one aircraft type, though sometimes they're more rarer in some types of aircraft than other.

-zygodactyl: another very common and non-exclusive feet type, these kinds of feet are more common in the smaller and lighter aircraft, especially in civilian and non-combat aircraft. some elkinets use zygodactyl feet to hold and manipulate objects, much like parrots do with their feet. skiplanes have a unique variation of this foot type that's semi-palmate (partially-webbed).

-dromaeosaurid: heading to the more exclusive kinds of feet, the dromaeosaurid feet (also known as raptor feet) are only seen in the small and medium-sized aircrafts. they are especially common in combat aircraft like bombers and fighters. although tipped with a large talon, rarely is the big toe ever used in combat outside of the military.

-webbed: while these feet are often in the shape of you average palmate (Like ducks and geese), they can also take the form of lobate feet (Like grebes and coots). they are exclusively seen in seaplanes and very rarely in other types. curiously enough, those rare times are often in navy and coast guard aircraft. as expected, these provide better mobility in water.

-carnosaur: of all the feet types, this is the only one that is incapable of perching or grabbing due to a heavily reduced rear toe. these are only found in transport aircraft and no other kinds have them. they are especially common in some of the biggest and heaviest of them.

TAIL     beyond with flight, the tail also serves as a balancer to keep elkinets on their two legs. the tail is flexible and capable of moving around. the tail can be used as an indicator of emotions; an example is their tail swaying side to side. this is typically associated with being happy or content.      all elkinets have a tailbone and some form of a tail. the twin-boomed aircraft are very interesting, in that their tail is boneless and part of the arm. each boom is separated from each other, allowing them to move independently. when in flight, however, they are held together by setae, same thing on the wingtips. they are limited in movement, however, and are primarily controlled by the base of the boom.

SIZE AND HEIGHTS     from nose to tail, a normal elkinet is around the same lengths as their aircraft counterparts. however, that is not always the case; elkinets also have a pygmy version of them. pygmies are half the size of a normal elkinet, and come into the world of two way; being born by pygmy parents (Most common) or being born from a normal elkinet (very rare). the latter occurs when there is a lack of natural resources (water, food, etc.). this has, historically, happened on island and island continents, but in modern time it became prevalent in places of poverty. apart from the size, they're about the same as a normal elkinet. sometimes, especially with some of the smallest aircraft, pygmies can be smaller than humans.     with individuals, however, there are some variations in size much like us. some individuals of the same age and kind can vary a little bit. this is especially in females, since they tend to be slightly larger than males.

GENDER DIMOPHISM     female and male elkinets look almost identical, though there are some external giveaways to their gender.

-females: females, like said previously, are slightly larger than males. in addition they'll have some much fuller eyelashes, and often have a slightly more curved chest than the males (of which is mostly fat)

-males: the almost opposite, males are slightly smaller, with a flat chest and less full eyelashes (or in my drawing style no eyelashes).

[tumblr edit: later on, i would call males "toms" and females "sheplanes". also, yes, i know, typical "girl vs boy" anthropomorphisation. come complain to me..]

COLORS AND LIVERY     contrary to our aircraft, elkients do not have any obvious letters, numbers or symbols as part of their liveries. they only have colors, patterns and markings (seen on last image). at most they'll have markings that very, very vaguely look like said symbols. the closest thing to having those as part of their livery is if it's tatooed on, otherwise it is worn as some form of clothing or accessory.     while most of their livery is based on their real-world counterpart, they practically can have any kind of colors and liveries.

GENETICS & HYBRIDS

    all elkinets are part of the genus aeros, and because of how closely related different kinds are, there is indeed a possibility to get a hybrid. between different aircraft, hybrids can vary from uncommon to very rare. in all cases, hybrid elkinets are usually a mix-and-match thing, having certain physical attributes greatly resembling one parent than the other, the most common of which is being one parent' species and the other's colors/livery. sometimes, though, other body parts can be taken into account like head, body, tail, engines, etc etc...however, there is more at play than just having the parents be two separate species.     see, what comes out depends on the size difference between the parents. usually, the rule of thumb is that the smaller the mother is compared to the father, the more likely it is the baby will be the mother's species. here, i have a set of examples (disclaimer, I'm horrible at percentages):

if the mother's smaller than the father, it's the following statistics: -60%-90% chance of baby being mother's species -30%-5% chance to be father's species -10%-5% chance of baby being hybrid

if father's smaller than the mother, the statistics are swapped: -60%-90% chance of baby being father's species -30%-5% chance of baby being mother's species -10%-5% chance of baby being a hybrid

if both parents are close to or of exact same size, then it's different: -35%-40% chance of baby being father's species -35%-40% chance of baby being mother's species -30%-20% chance of baby being hybrid 

    of course, this is if the baby is conceived naturally. though, in the more modern age, parents can instead go to specialist to have their baby artificially conceived. the most common way of doing this is having a fertilized egg sit in an artificial "womb" until it developed into a more proper elkinet egg. these artificially conception creates the same chances of what comes out as if the parents were of same size. this method, however, is pretty costly and does require the two parents to go through paperwork and make sure that they're capable of taking care of the child.

ENGINES AND FLIGHT     just like real-world aircraft, elkinets are fully capable of flight. however, their flight is pretty different than our aircraft.

ENGINES: the elkinets fly primarily with their engines. the engines are near-identical to our non-living aircraft, having the near same mechanisms and what not, particularly the insides of it (fanblade, compressors, turbines, ect). however, the materials are actually partially-biological, having keratin make up at least 30% of those part. this makes elkinets (alongside all other aeronoids) one of the very few times a biomechanical organism has evolved naturally.     another thing that sets the elkinet's engines apart from normal aircraft is how resistant they are. things that would normal damage or strait up ruin an normal engine (water, debris, ect) have little to no effect on the elkinet's. their engines (if on the wings) are also firmly attached to the arms via cartilage, so it would take significant force or trauma for them to come off. however, the insides of the engines are also pretty sensitives, and they definitely would feel debris if it was caught up in there. thankfully the debris usually will comes out by itself with a few start-ups.

FLIGHT IN GENERAL: elkinets take off by having their engines at near-full power and either launching themselves into the air or getting a brief running start. once they've got air, engines go into full power and they fly off.      regardless of what aircraft they are or the type of engines they got, all elkinets fly at the subsonic speeds of 200-210 mph (dependent on respective aircraft/engine types). since elkinets have no flaps or speed brakes, they usual stop/slow down by positioning themselves so that they reduce their speed (Much like what birds do when they come to land). elkinets will even deploy reverse thrust if they need to further slow down.     like that famous saying from Issacs newton goes "what goes up must come down", and that stays true for the elkinets. for one, flying itself can burn alot of calories, especially if the engines are constantly running. another thing that limits the amount of time in the air is the fact that they have to hold their arms / wings strait out. while they have evolved to hold their arms out for long periods, they cant hold them out forever.     in addition to normal flight, all elkinets are capable of gliding as well. and, depending on engine placement, they can also hover in the air even if they aren't vtol aircraft themselves. this, like with birds and the above stated, takes up lots of energy.

DEVELOPENT & LIFE CYCLE     like practical any organism, elkinets have a life cycle and different life stages. typically, elkinet on average live for roughly 110-120 years, and have weird developmental stages too. although they reach a certain point where growth is suddenly slowed, elkinets never really stop growing. some of the largest elkinets are also some of the oldest. there are considered five different life stages

EGG (0-3 months): five months after conception's, the mother will give birth to an egg. the egg, while varying in color and sizes depended on species, will always be of the same shape. elkinet eggs are soft and leathery like a lizards, and create their own heat. however the egg must be protected and kept an eye on at all times, should the egg ever hatch or get damaged. the parents can either place the egg in a special nursery, or take the egg wherever they go. the gender of the child can be told two to three weeks prior to hatching via ultrasound.

INFANT (hatchling/hatchlet), 3 months-4 years: when first hatched, the infants eye are closed for the first five days. infants lack the tomnium when first born, an only gain them once two years of age. in the meantime, they are fed bland, pureed food (Not unlike our baby food), or if one to go the all-natural route, pre-chewed food.     infant elkinets begin "walking" at age 5-8 months. or, more accurately, hopping. they start by bunny-hopping, that is lopping on all fours not unlike that of a rabbit. eventually, they'll begin to clumsily hop on two legs like a drunk kangaroo, and later at age 3, begin to walk normally. infants, before they're able to start talking, will make various chirps and hisses (which is said to be very much like that of a cheetah cub, caracal or baby racoon). they are also, obviously, incapable of flight since they lack the parts nessisarly to fly.

CHILD (aeroling), 4-14 years: at this age, not only are they talking and eating solid foods, but they've also developed the engine parts that allow them to fly. however, the engine are still very weak; at most they can glide short distances, so they need to exercise them in order to be able to properly developed flight. it's also at this age that they're put into the education system.

TEEN (Middling), 14-27: the midway point from child to adult. at exactly 16-17 they're considered sexually mature, however it is considered that the age of 22 is the appropriate age of consent. at this point, they're fully capable of flight, and at 19 they're considered old enough to work, go to collage or join the military.

ADULT (30-90): at this point, the growth is heavily slowed, but not stopped. apart from that, this is your typical adult stages you'd expect.

ELDERLY (100-130+): the final stages, elkinets begin to loose their flying abilities as their engines begin to weaken. any form of bright colors they had become darker and duller, and their health complications begin to rise. most elkinets will end up with mobility issues and will inevitable be unable to walk. usually these complications strikes larger aircraft earlier than the smaller ones

now, in some freak circumstances an elkinet's growth does not slow down much, if at all. it's very rare, and this most commonly happen in the pygmy elkinets. while this does sound cool, it only leads to a shorter lifespan.

MISC TRIVIA  here, i have some various info and facts about the elkinets that don't entirely fit into the different points.

-elkinets, and practically all other aeronoids can survives slightly more hotter /colder temperatures than we do. they've only go into hypothermia (cold) when their body temperature hits 89.6 F, and hyperthermia (hot) when it hits 105.8 F. both those temperatures would kill us humans without immediate help. however they obviously try to avoid those dangers and will stay cool / warm when they can.

-elkinets will also wear clothing and accessories, not just for the above reasons but also for other reasons like vanity or rules and regulations.

-elkinets do indeed have vehicles. not surprisingly, most of them are aerial-base, but there are a plethora of land and water ones too. most of these vehicles, however, don't go as fast as you think. with the flying vehicles, they only go slightly faster than the fastest elkinets, if not the same speed as them. they're primarily used for long-distance travel and heavy transport.

-adult elkinets still do make animalistic noise, though unlike when they're young these noises are more akin to large carnivorans, such as growls, roars, screeches, and yowls. however, the noises aren't part of their actual language, they're more of sounds that display certain emotions. 

-while capable of eating thing us humans can eat, there are also some foods they only they're capable of eating. holly berries are a good example, as they've been domesticating them for years for things like pastry filling, candy and rum (which, funny enough, made them less poisonous to humans).

-elkinets prefer to sleep on the bellies as it's more comfortable as apposed to sleeping on their backs

-elkinets usually do not naturally have any armaments to them whatsoever (missiles, guns, ect). those are usually part of armored suites worn by the military.

anyways, that's this post for now.