In my last post, I began talking about three characteristics of the Tyrannosaurus from Prehistoric Planet that I knew were based on speculation. We have already discussed the fuzz on the head of Tyrannosaurus. Now we have two more features to consider.
My second comment about the Prehistoric Planet Tyrannosaurus is less a contradiction of the facts and more of a warning against the claim of accuracy. This problem has to do with its mouth. Notice anything missing? Here, check out this picture of the Daspletosaurus from Planet Dinosaur. Sure, it is not Tyrannosaurus, but it is a member of the family Tyrannosauridae, so it is a good substitute. Notice anything present in this image but absent in the image of the Prehistoric Planet Tyrannosaurus? Teeth!
Now, the Prehistoric Planet Tyrannosaurus has teeth. However, its teeth are not visible when its mouth is closed. Why? Because the Prehistoric Planet Tyrannosaurus has lips. These lips are large enough to cover up the teeth when the mouth is closed.
Lips on tyrannosaurs have been debated for a long time. My first exposure to the idea that Tyrannosaurus had lips was when I read the 1986 book The Dinosaur Heresies.[1] In that book, the author, Bob Bakker, argued that Tyrannosaurus likely had lips covering its teeth when the mouth was closed. At the time, he was presenting a “heretical” view, as most reconstructions of dinosaurs at the time showed them with little to no lips. So as a first note, the idea of Tyrannosaurus having lips is not a new idea, but one that is at least 30 years old.
The idea of lips on dinosaurs has gone back and fort. In 2017, scientists compared the skull of a Daspletosaurus to the skulls of alligators, crocodiles, and birds, and determined that, based on the location of grooves in the skull representing the location of nerves and blood vessels, Daspletosaurus had a skull covered with flat scales, a lot like a crocodilian.[2] Such an arrangement appears to preclude lips: crocodiles lack lips, so if the skin of the face of Daspletosaurus had crocodile-like skin, then it stands to reason that Daspletosaurus and Tyrannosaurus lacked lips.
Now, that 2017 article was in no ways definitive. Opinions still differ among paleontologists, and a more recent article on the topic has pointed out that there is simply not enough information to make a definitive call on the presence or absence of lips on theropods like Tyrannosaurus.[3] However, that means that a lipless Tyrannosaurus is as scientifically accurate as a lipped Tyrannosaurus. Thus, the Prehistoric Planet Tyrannosaurus should get no special accolades for having lips. It doesn’t represent the latest and most accurate in paleontology: it represents an old idea (that is at least as old as 1986) that the paleoartists of Prehistoric Planet decided to use on their Tyrannosaurus. The lips represent opinion rather than accuracy.
My last thing to say about the Tyrannosaurus on Prehistoric Planet has to do with its overall appearance. The Tyrannosaurus on Prehistoric Planet may appear to be a bit… chubby. The body, hips, and tail barely have any features to them. One smoothly blends into the other without any noticeable joints or bony protuberances.
The outward appearance of a dinosaur is an area where speculation and opinion will naturally reign supreme. How do we reconstruct the fleshy parts of Tyrannosaurus? Sure, we can look at the location of muscles and get an idea of the size of the muscles by the size of the muscle scars on the bones, but that is only part of the answer. What was the skin like, and I don’t mean just the surface of the skin. I mean, was the skin thick, supple, and healthy, or did it have a thin skin stretched tight over the muscles and skeleton?
That latter description, thin skin pulled tightly over the skeleton, will irk many paleoartists and paleontologists. Why? That is what “many” older reconstructions of dinosaurs looked like. Now, I put “many” in quotation marks, because while it is certainly true that some reconstructions of dinosaurs portray them as skin pulled tight over a skeleton, it is my observation that not all were like that. Nevertheless, this type of reconstruction is so reviled, it is called “shrink-wrapping.” Paleoartists and some paleontologists so despise shrink-wrapping that they actively argue against it. Notably, one of the more outspoken paleontologists against shrink-wrapping is Darren Naish,[4] who was also one of the consultants for Prehistoric Planet. Thus, it is no surprise that a Tyrannosaurus that actively avoids any hint of shrink-wrapping (i.e. is on the chubby side) would appear on Prehistoric Planet.
I agree that many prior reconstructions of dinosaurs tend to skimp on the skin. However, without knowing exactly how thick dinosaur skin was, any reconstruction, whether shrink-wrapping or chubbifying, will necessarily be speculative. It is also perhaps worth noting that the thickness and tightness of the skin can vary from one part of the animal to the next. Going back to the 2017 article about the face of Daspletosaurus, their reconstruction of the Daspletosaurus face was based in part on crocodilian faces, which have thin skin held tight to the skull. In other words, the heads of crocodiles are shrink-wrapped. True, the rest of the body is not, but that only highlights that reconstructing the skin of dead animals is complex and difficult, if not impossible to do (and that shrink-wrapping is not an abomination to science).
The truth is, I kind of appreciate that the Prehistoric Planet Tyrannosaurus is done differently, portraying it with thicker, more supple skin. Sure, it looks a little chubby to me, but I appreciate that it was deliberately made to show the opposite of shrink-wrapping. However, I also can’t help but see the Tyrannosaurus as a statement about shrink-wrapping. I can’t help but hear Naish telling the artists working on Prehistoric Planet, “Let’s get it right this time. Let’s avoid all shrink-wrapping,” and all of them giving a big, enthusiastic thumbs up. And then they went slightly overboard, making a chunky Tyrannosaurus rather than simply a not-shrink-wrapped Tyrannosaurus. But hey, that’s my opinion, but then again, the Tyrannosaurus represents the opinion of Naish and the paleoartists working on Prehistoric Planet to begin with.
That is my final takeaway. It is not necessarily that the Tyrannosaurus from Prehistoric Planet is inaccurate (except perhaps for the fuzz), it is just that there are features that represent opinion rather than accuracy. In truth, it is probably closer to a real Tyrannosaurus than your average reconstruction. Nevertheless, it has its issues. Fuzz is put on the Tyrannosaurus in spite of the fact that no such integument has ever been found on a Tyrannosaurus or any of its closest relatives. Lips were put on the Tyrannosaurus when the evidence for such lips are, at best, ambiguous. Finally, the Tyrannosaurus is a lot fatter and rounder than many other reconstructions, and this has more to do with personal preference of appearance than with any actual research about the rotundness of Tyrannosaurus.
Just be aware: whenever you see a reconstruction of a dinosaur, you are not seeing the dinosaur itself. Rather, you are seeing a paleoartist’s opinion of what that dinosaur looked like.
Thoughts from Steven
[1]Bakker, Robert (1986) The Dinosaur Heresies: New Theories Unlocking the Mystery of the Dinosaurs and Their Extinction Zebra Books, New York, New York, pg. 142-144
[2]Carr, Thomas; David Varricchio; Jay Sedlmayr; Eric Roberts; Jason Moore (2017) “A new tyrannosaur with evidence for anagenesis and crocodile-like facial sensory system” Scientific Reports 7:44942
[3]Bouabdellah, Florian; Emily Lessner; Julien Benoit (2022) “The rostral neurovascular system of Tyrannosaurus rex” Palaeontologia Electronica 25.1.a3. As an interesting aside, this article cites a non-academic 2018 article written by Greg Paul (“Nonornithischian dinosaurs did too have lips, probably big lips, here’s why” Prehistoric Times 127: 44-49) as a representation of the “theropods have lips” side. Two things to note: Greg Paul, a paleoartist, one again makes an appearance, and two, the debate about lips has been carried out of academic circles into a debate among the general public.
[4]onway, John; C. M. Kosemen; Darren Naish (2012) All Yesterdays: Unique and Speculative Views of Dinosaurs and Other Prehistoric Animals, Irregular Books, Location 530-555
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