Wednesday 1 April 2020

A History of Thick Dinosaurs

Warning: This was written as an April Fools gag and is therefore filled with complete nonsense. 

One of the oldest and most well-known features of dinosaurs was their extraordinary thickness. This is because it is one of the most easily readable features of their skeleton. The thickness, in scientific terms called Robustus stultus, of a dinosaur can be easily determined by measuring the diameter of the caudopygidium bone of the hip. Contrary to popular belief, it was not the teeth that were the first discovered fragments of Iguanodon, but rather its caudopygidium. This fact was however kept secret by Gideon Mantell for over 30 years, as he believed that: “Nobody would have believed the Lord was capable of creating a magnificent beast of such robust girth and allow it to go extinct. What a waste of beauty.” (Mantell 1853). As he revealed the secret on his deathbed, Richard Owen declared that a reptile can only be considered a dinosaur if it has erect legs, five fused sacral vertebrae and its caudopygidum’s diameter measures at least 30 centimeters, famously defending this choice by saying: “I like big saurians and I may not lie”(Owen 1893). This discovery he also used to counteract the Darwinian notion of evolution being a survival of the fittest and instead proposing that it was a survival of the thickest. With this began the search for the dinosaur possessing the widest  Robustus stultus, culminating in the North American Bone Wars, during which O.C. Marsh and E.D. Cope fought tooth and nail to find the dinosaur with the widest caudopygidium bone (giving the war its name). Both claimed to have discovered the thickest dinosaurs, with Cope having named Camarasaurus supremus (the supremus referring to the 1 m thickness of the caudopygidium) and Marsh describing Stegosaurus (thought to have had a brain in each Gluteus maximus alone just to handle all that girth). But they were both deceived, for an even thicker dinosaur was found by Barnum Brown. Said dinosaur, Tyrannosaurus rex, was declared king of the dinosaurs not because of its height, but because it had the largest caudopygidium of any lifeform known at that point. Dinosaurs with an even bigger Robustus stultus have however been discovered since then, all curiously coming from Bad Segeberg.

With such a dynamic history, it should come to no surprise that the topic of dinosaur thickness has also found its way into paleoart. In this post I therefore want to present the ten most classic and accurate examples of dinosaur-thickness.

1.     Gorgosaurus, by Zdeněk Burian
Fig. 1
Here we see the Cretaceous tyrannosaurid Gorgosaurus attacking two Styracosaurus. There exist three different versions of this piece, one from 1948, one from 59 and this one here from 61. Each time Burian made sure to make the hindquarters of the theropod thicker and more defined than before in order to be as accurate to the caudopygidium bone as possible. With each iteration the Styracosaurus at the back also comes closer, presumably to admire the girth of those thunder thighs.

2.     Vulcanodon, by John Sibbick
Fig. 2.
Behold the pinnacle of thickness, which is Vulcanodon. As we can see here, the artist John Sibbick chose to depict this dinosaur according to the German motto “Wer schön sein will muss leiden” (He who wants to be beautiful has to suffer). Just look at that sad face. It reminds me of my header-image of the sprawling Heinrich Harder Diplodocus, which seems to smile through the joint-pain.

3.     Agathaumas by Charles R. Knight
Fig. 3.
Agathaumas is a totally real, valid genus of ceratopsian dinosaur discovered in 1872, here reconstructed by classic artist and bonsai-tree-collector Charles R. Knight. While Knight was at first often reluctant to give dinosaurs their proper girth, he was convinced by concept after subscribing to Owen’s “survival of the thickest” concept. Here we see him depict the then novel concept of dinosaurs not just being massive, but also possessing armored thickness in order to protect their hardly gained Robustus stultus.

4.     Gourmand, by Dougal Dixon
Fig. 4.
Ganeosaurus tardus, also called the Gourmand, is not a real dinosaur, but rather a thought-experiment of what a tyrannosaur might look like if it lived today. According to its creator, the thickness of dinosaurs was gradually increasing towards the end of the Cretaceous, so if they had not died out they may have perfected their Robustus stultus to an unprecedented degree. To make space for and maintain such a high thickness, however, the animal would have had to get rid of useless organs and been constantly eating protein-rich food. This is why the Gourmand has lost its forelimbs and is depicted here engaging in the highly nutritious act of eating ass.

5.     Gorgosaurus, again by Zdeněk Burian
Fig. 5.
Burian, it seems, was irresistible to the caudoypgidium-diameter of Gorgosaurus, which is why he produced more than one piece of the theropod, seen here attacking the ankylosaurid Scolosaurus (in an earlier sketch of this piece it is Edmontonia). What Burian depicted here is the most accepted hypothesis for the dinosaur’s extinction: Its haunch and belly were so girthy (likely to attract mates) that the animal had trouble bending down to feed or drink, just like me after the holidays. This makes Gorgosaurus a prime example of overspecialization. Look at that smug look on that Scolosaurus’ face. It knows that the fatass cannot reach it.

6.     Triceratops, by Jean Zallinger
Fig. 6.
Tired of all the talk about thick dinosaurs, American paleontologist Roy Chapman Andrews wanted to instead explore the origin of human thickness. For this, however, the dolt did not go to Africa, but to Mongolia instead in search for the missing link between human- and baboon-butts. He was to be disappointed, as he instead found many more thick dinosaurs. Instead of admitting his failure to find the missing link, he made a career out of being a dinosaur-expert, pretending to have always been searching for dinosaur bones in Mongolia. He went on to write several dino books aimed at children, one of which, In the Days of the Dinosaurs was illustrated by Jean Zallinger, who had an extraordinary fondness of plus-size ceratopsians it seems.

7.     Tyrannosaurus, by Rudolph Zallinger
Fig. 7.
Rudy here was the husband of the famous Jean Zallinger, though his only notable work is a very obscure mural called The Age of Reptiles. Why it is so unknown is hard to say, as it is notable for most detailedly depicting the accurate amount of thickness of the mighty Tyrannosaurus. Perhaps he was simply ahead of his time.

8.     Parasaurolophus, by John Conway
Fig. 8.
Here we have John Conway once and for all proving that dinosaurs can also be thick in modern paleoart. It was made for the book Thick Yesterdays in which the author attempted to counteract the ongoing trend of slimming down dinosaurs in paleoart. The overall motto was: “Real dinosaurs have curves”. His co-author Nemo Ramjet produced even thicker dinosaurs, which I cannot show here for censorship reasons. Think of the children!

9.     Euoplocephalus, by Gregory S. Paul
Fig. 9.
Much like Knight, Paul was into more slim dinosaurs, but even he could not resist the attraction of a thick ankylosaur. “I regret nothing”, were his last words before he lumped this genus into the same as Nodosaurus and reclassified all of Thyreophora as a subgroup of glyptodonts. 

10.  Iguanodon, by Benjamin Waterhouse Hawkins
Fig. 10.
Here we have the original and to this day still most scientifically accurate reconstruction of Iguanodon. Hawkins took great care to accurately model how the fat-rolls would bend and stretch as the animal lied on its belly. This was actually a very dangerous act, as Owen cautioned the artist to not sculpt the fat too accurately, as the prude Victorian society of the time was not yet ready for such a brash display of thickness. Hawkins did not listen and got away with it in the British Crystal Palace. However, when he tried doing the same in the planned Paleozoic Museum of the New Yorker Central Park, the even pruder society of 19th century America would not have it and all his models were demolished with sledge-hammers by famous creationist mobster William Magear Tweed. They were just not ready for the thickness yet. 

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Literary Sources:

  • Andrews, Roy Chapman: In the Days of the Dinosaurs, New York 1959.
  • Conway, John/Kosemen, C.M./Naish, Darren: All Yesterdays. Unique and Speculative Views of Dinosaurs and Other Prehistoric Animals, UK 2012.
  • Dixon, Dougal: The New Dinosaurs. An Alternative Evolution, London 1988.
  • Mantell, Gideon: May the Lord forgive me for what I am about to do, London 1853.
  • Norman, David: The Illustrated Encyclopedia of Dinosaurs, London 1985.
  • Owen, Richard: On the thickness of fossil reptiles, London 1893.
  • Schalansky, Judith: Die Verlorenen Welten des Zdeněk Burian, Berlin 2013 (Naturkunden 8).
  • Volpe, Rosemary: The Age of Reptiles. The Art and Science of Rudolph Zallinger’s Great Dinosaur Mural at Yale, New Haven 2007.
  • White, Steve: Dinosaur Art. The World’s Greatest Paleoart, London 2012.

Online Sources:

Image Sources:
  • Fig. 1: Schalansky 2013, p. 134-135.
  • Fig. 2: Norman 1985, p. 92.
  • Fig. 3: Wikimedia
  • Fig. 4: Dixon 1988, p. 75.
  • Fig. 5: Schalansky 2013, p. 138-139.
  • Fig. 6: Andrews 1959, p. 57.
  • Fig. 7: Volpe 2007, foldout.
  • Fig. 8: Conway 2012, p. 51.
  • Fig. 9: White 2012, p. 39.
  • Fig. 10: Tetrapod Zoology


  1. This comment has been removed by the author.

  2. Brilliant article. I had to look up Agathaumas since the genus was new to me, and can't help sharing this charming sketch by none other than E.D. Cope:

    The poor individual seems to suffer from hyperthyroidism, resulting in a pronounced goitre and the loss of most of its thickness.

  3. That "Gourmand" is like a snake with legs.

    It is the stuff of nightmares.