I’m overloaded with work and deadlines, and unable to complete anything new. So please enjoy this classic Tet Zoo article from the archives, originally published at ver 2 back in 2008 (an archived version is here)…
When Tyrannosaurus rex was named by Henry Osborn in 1905, it was described alongside a second gigantic theropod, the armour-plated, Ceratosaurus-like Dynamosaurus imperiosus, collected in 1900 near the Cheyenne River, Wyoming. Unlike T. rex, Dynamosaurus possessed irregularly shaped bony plates on its back and sides. These later turned out to be from an ankylosaurid (probably Ankylosaurus), and in fact small craters on the scutes look like T. rex tooth marks, suggesting that the scutes were part of the tyrannosaur’s stomach contents* (Carpenter 2004, Breithaupt et al. 2008a, b). Osborn later realised that Dynamosaurus was synonymous with T. rex, but continued to think that the animal possessed armour plates (Osborn 1917).
* Ankylosaurid armour may well have helped protect these animals from tyrannosaurid predators, but the awesome bite strengths reconstructed for T. rex suggest that the biggest tyrants might still have been able to do serious, fatal damage to an ankylosaurid. Scott Hartman once depicted this in a reconstruction titled ‘Armor? What armor?’.
In 1960 the Dynamosaurus specimen was (together with parts of three other T. rex specimens) sold to the then British Museum (Natural History), and here it was mounted in the museum’s old dinosaur gallery in a rather ‘modern’ pose: that is, with its body and tail near-horizontal and its tail well up off the ground. Those who’ve commented on this have usually noted that the museum’s Barney Newman deliberately chose to depict the animal in this way. Indeed, Newman (1970) explained how correct articulation of the vertebrae meant that the animal simply had to be arranged like this.
Newman was not, actually, the first person to depict a tyrant dinosaur in a horizontal-bodied posture. Erwin S. Christman illustrated the T. rex back and tail in horizontal pose for Osborn’s 1917 paper on theropods (Osborn 1917), and one might conclude from this that Christman (and perhaps Osborn too) actually advocated a wholly ‘modern’ posture for tyrant dinosaurs. In, however, an earlier paper, Osborn (1913) had drawn attention to Christman’s on-going work on reconstructing the life postures of theropods, and it seems from words used here that Christman imagined theropods to walk with their backs held diagonally, their tails sloping down to the ground. Various dinosaur reconstructions supervised by Osborn during the 1920s are depicted this way too, so I think that Osborn regarded bipedal dinosaurs as ‘diagonal-bodied’, not ‘horizontal-bodied’.
Newman (1970) noted that Ned Colbert had depicted other large theropods (Allosaurus and Gorgosaurus) in horizontal postures in his 1965 book The Age of Reptiles, and I think that what Newman was referring to here are Margaret Colbert’s life reconstructions of these animals. They indeed show horizontal-bodied big theropods in a book of 1965.
So, was Newman’s tyrannosaur mount as far-sighted and innovative as might appear? It soon entered the ‘mainstream’ literature. Halstead (1975), for example, illustrated T. rex in the postures depicted by Newman, also repeating Newman’s idea that tyrannosaurs might have used their short didactyl forelimbs as props when raising themselves from a resting posture. But Newman’s ideas weren’t entirely modern. He thought that the tail must have swung far to the side with each step, and that these dinosaurs must have walked with an “ungainly waddling” rather “than the formerly postulated majestic striding” (p. 123). Modern work has not supported this idea, which never seemed reasonable anyway.
What interests me in particular is Alan Charig’s claim that the BM(NH) T. rex “was mounted with its body in a far too horizontal position: this was done because it would otherwise have been too tall for the Gallery. Newman, who made the mount, has attempted to rationalise this (1970) by stating that the posture was much more bird-like than is suggested by earlier mounts” (Charig 1972, p. 137). Charig and Newman were at loggerheads, and this exchange on the posture of the BM(NH) T. rex “did nothing to improve relations between the two” (Moody & Naish 2010). But, personal spats aside, this must mean that Charig regarded Newman’s re-posed T. rex to be too horizontal, that Charig wanted it to be more upright. Maybe not bolt upright like a standing kangaroo, but more diagonally posed, at least.
Whatever the true explanation behind the posture of the London T. rex, I remain upset that I never got to see it. And I’ve decided that I want this article to serve as a repository for images of that now lost mount, so I’ll be adding additional pictures of it here, as I find them. Thanks if you know of any that aren’t already shared here.
For previous Tet Zoo articles on tyrannosauroids and related issues, see…
Naish and Barrett's Dinosaurs: How They Lived and Evolved, November 2016
Ornithoscelida Rises: A New Family Tree for Dinosaurs, March 2017
The Second Edition of Naish and Barrett’s Dinosaurs: How They Lived and Evolved, November 2018
Dr Angela Milner and the Discovery of Baryonyx, August 2021
Two New Spinosaurid Dinosaurs from the English Cretaceous, September 2021
The Third Edition of Naish and Barrett's Dinosaurs: How They Lived and Evolved, February 2024
Refs - -
Breithaupt, B. H., Southwell, E. H. & Matthews, N. A. 2008a. The ‘powerful imperial lizard’ Dynamosaurus imperiosus: the world’s first Tyrannosaurus rex comes to London. In Moody, D., Buffetaut, E., Martill, D. & Naish, D. (eds) Dinosaurs and Other Extinct Saurians: A Historical Perspective. The Geological Society of London (London), pp. 22-23.
Breithaupt, B. H., Southwell, E. H. & Matthews, N. A. 2008b. Wyoming’s Dynamosaurus imperiosus and other discoveries of Tyrannosaurus rex in the Rocky Mountain West. In Larson, P. & Carpenter, K. (eds). Tyrannosaurus rex: the Tyrant King. Indiana University Press (Bloomington and Indianapolis), pp. 57-61.
Carpenter, K. 2004. Redescription of Ankylosaurus magniventris Brown 1908 (Ankylosauridae) from the Upper Cretaceous of the Western Interior of North America. Canadian Journal of Earth Sciences 41, 961-986.
Charig, A. J. 1972. The evolution of the archosaur pelvis and hind-limb: an explanation in functional terms. In Joysey, K. A. & Kemp, T. S. (eds) Studies in Vertebrate Evolution. Oliver & Boyd (Edinburgh), pp. 121-155.
Colbert, E. H. 1965. The Age of Reptiles. Weidenfeld and Nicolson, London.
Halstead, L. B. 1975. The Evolution and Ecology of the Dinosaurs. Peter Lowe, London.
Moody, R. T. J. & Naish, D. 2010. Alan Jack Charig (1927-1997): an overview of his academic accomplishments and role in the world of fossil reptile research. In Moody, R. T. J., Buffetaut, E., Naish, D. & Martill, D. M. (eds) Dinosaurs and Other Extinct Saurians: A Historical Perspective. Geological Society, London, Special Publications 343, pp. 89-109.
Newman, B. H. 1970. Stance and gait in the flesh-eating dinosaur Tyrannosaurus. Biological Journal of the Linnean Society 2, 119-123.
Osborn, H. F. 1913. Tyrannosaurus, restoration and model of the skeleton. Bulletin of the American Museum of Natural History 32, 91-92.
Osborn, H. F. 1917. Skeletal adaptations of Ornitholestes, Struthiomimus, Tyrannosaurus. Bulletin of the American Museum of Natural History 32, 133-150.