Deviation Actions

T-PEKC's avatar

Prenocephale prenes

Published:
By
136 Comments
25K Views
Reconstruction of Prenocephale prenes, showing different types of speculative behavior and hypothetic presence of filamentous integumentary structures in pachycephalosaurs. This is my first entry for “All Your Yesterdays” contest - nemo-ramjet.deviantart.com/art….

Prenocephale prenes is pachycephalosaurid ornithischian from the Nemegt formation (Mongolia). It was about 2.4 meters long and lived during the late Campanian, or early Maastricthian times (~ 72 million years ago). It was herbivorous animal. Here, it’s shown hiding from big predator, the theropod Alioramus remotus.

The filamentous integumentary structures depicted here are speculative, but similar integumentary structures, made of beta-keratin and located mostly in the dorsal part of the torso, are found in the ceratopsian Psittacosaurus (Ceratopsia is a sister clade of Pachycephalosauria), and in the heterodontosaur Tianyulong. Both of them being ornithischian dinosaurs (former being more derived, and the latter more basal ornithischian), leave open the possibility that such structures could have been more distributed among the members of the group, and even homologous to the feathers in theropods. Reconstructing Prenocephale with filaments is my way to support the idea (it’s only idea for now given the fossil material at hand and the lack of studies testing this hypothesis) that the presence of filamentous integumentary structures is a basal trait for Dinosauria.

Here, the filaments are located in between the scales, as similar arrangement of feathers and scales is known in some modern birds. This can be explained by Prum’s model for feathers evolution, in which feathers (or protofeather filaments) are homologous in the embryonic stage of animal’s development, and later form different types of integument, which sometimes can coexist.

The majority of the body is covered with scales, following the model seen in Triceratops – subrectangular scales on the ventral side of the body, and finer scales above them. Some of the scales are bigger, with oval form, and are circled by smaller scales, forming rosette-like pattern.

It’s known that at least some dinosaurs (Oryctodromeus and possibly its closest relatives) had an adaptations of digging and were able to live in dens. Similar adaptations are not known for pachycephalosaurids (as far as my knowledge goes), but many digging/denning animals have no obvious adaptations for such behavior/life style. Here, Prenocephale is using a den to hide from a predator. I won’t go as far as stating the burrow was made by the dinosaur, it may just use already existing one.

But denning is not its only protection. If some pachycephalosaurs really were able hide underground from time to time, then they could have gone even further by using mimicry. Because of the specific shape of their head - the dome structure, some of them could have used it to mimic the rocks around, thus increasing their chance to not be noticed by the predator.

References:

Mayr, G., D. S. Peters, G. Plodowski, O. Vogel. 2002. Bristle-like integumentary structures at the tail of the horned dinosaur Psittacosaurus.- Naturwissenschaften, 89, 361-365.

Paul, G. S. 2010. The Princeton field guide to dinosaurs.- Princeton University Press (for Prenocephale skeletal drawing; as obviously seen, neither his style, nor the pose of his skeletal drawing were used in any form in my artwork).

Prum, R. O. 2003. Are current critics of the theropod origin of birds science? Rebuttal to Feduccia (2002).- The Auk, 120, 2, 550-561.

Varricchio, D. J., A. J. Martin, Y. Katsura. 2007. First trace and body fossil evidence of a burrowing, denning dinosaur.- Proceedings of Royal Society Biological Sciences, 274, 1361-1368.

Xu, X., X. Zheng, H. You. 2009. A new feather type in a nonavian theropod and the early evolution of feathers.- Proc. Natl. Acad. Sci., 106, 3, 832-834.
Image details
Image size
7853x6902px 40 MB
© 2013 - 2021 T-PEKC
Comments136
Join the community to add your comment. Already a deviant? Log In
android65mar's avatar

Ilove the idea of burrowing dinosaurs- almost as if the top of it's skull is disguised as a rock. Exceptionally fine draughtsmanship.;P

kitxunei's avatar
This is great. A very interesting idea, and excellent drawing execution as well!
T-PEKC's avatar
Tim64's avatar
soooo cute, amazing art work:D (Big Grin) Nod 
T-PEKC's avatar
it kind of like the movie the big red 1
reptilian-bird's avatar
Love the concept! Beautiful little piece.
T-PEKC's avatar
Misfit-a-saurus's avatar
Cool piece, and an equally cool concept! I really like the top of his head mimicking the surrounding rocks. Plausible and creative!
grisador's avatar
Probably true ! A burrowing ornithomimid species is already known.
Why not ? :)
T-PEKC's avatar
A burrowing ornithomimid? This is news to me. Is it possible to link me to a paper or something, because my Google Scholar search gave no results?
T-PEKC's avatar
Just as I suspected, for some reason you have confused the ornithopod Oryctodromeus with being ornithomimid. A burrowing ornithomimid would have been pretty interesting find.

Here is link to the paper describing Oryctodromeusrspb.royalsocietypublishing.or…

Also, I mentioned this animal as an "excuse" to portray a denning pachycephalosaur in the description of my deviation: "It’s known that at least some dinosaurs (Oryctodromeus and possibly its closest relatives) had an adaptations of digging and were able to live in dens. Similar adaptations are not known for pachycephalosaurids (as far as my knowledge goes), but many digging/denning animals have no obvious adaptations for such behavior/life style. Here, Prenocephale is using a den to hide from a predator. I won’t go as far as stating the burrow was made by the dinosaur, it may just use already existing one."
grisador's avatar
Sorry my fault.


Although the Oryctodromeus; at least partly proves; dinosaurs can burrow Or use underground nests
T-PEKC's avatar
Yes, it indeed does! It also disproves that old idea that all non-avian dinosaurs went extinct because even the small ones could not hide in burrows like mammals. :)
grisador's avatar
Agreed & Indeed. :nod:


That leaves another question thought. Why all smaller dinosaurs went extinct either ?
Metabolism ? A disease only effects reptilian animals; like non avian dinosaurs ?
T-PEKC's avatar
I don't think metobolism was deciding factor for their extinction (they were fast growing, most probably endothermic animals). Disease is absolutely out of question - there is no such a selective disease that is spanning over different groups, but affecting only particular taxa. Also disease cannot explain why small non-avian paravians, enantiornithes and alvarezsaurids died out, while birds survived.


My bet is that the deciding factor was ecology and the role animals had in their habitat - non-avian dinosaurs, as dominant terrestrail animals, were at the top of the food-chains and thus they were probably overspecialized and couldn't adjust fast enough to the devastating changes. It is usually the dominant and most specialized groups that get hit hardest during mass extinctions. Taxa with more general diets seem to cope better with severe changes in the environment.
View all replies
AntoninJury's avatar
T-PEKC's avatar
Thanks! Looking back at it from the distance of time, the idea seems so speculative that I am not sure at all what I was thinking back then. But it was fun coming up with something that much out of the box. :lol:
LeahCK's avatar
Awesome concept, and so beautifully illustrated.
T-PEKC's avatar
LeahCK's avatar
You are welcome!
CuteKittyWiddy's avatar
Ooh. They hide underground while their...head ....crests? Look liek rocks? ouo
T-PEKC's avatar
It is only speculation and not very likely one at that. But it was fun to play with the idea.
Join the community to add your comment. Already a deviant? Log In