History in Pictures

Moscow mandible, J. Fischer

The first images released to the public of Elasmotherium have been lost, for the most part. Named in 1808 (Fischer published the account in 1809), that is really a small matter, all things considered. The famed Moscow Mandible was illustrated many times, here by Johann Fischer in the 1809 description. At that time Fischer was the director of the Natural History Museum at Moscow University. The material is quite nice appearing, in this illustration at any rate. Mammal jaws are well known and researched and Fischer's description of this jaw element, which would go on to become the holotype of the genus, was about as typical as one would expect given the material and the time frame of its description. Completely regardless, this jaw and later material began painting a picture of one of the most interesting predecessors of the extant rhinoceroses. Fischer named the ancient mammal based on the teeth that he found in this jaw, making it even more important than if it were just a simple jaw. The name Elasmotherium is derived from the Greek elasmos (layered) and references the tree-ring like layering of enamel on the molars of the jaw. Those molars have large high crowns and are considered hypsodontid. Inferences made from hypsodont teeth include MacFadden (2000)'s statement that "as a general rule, extant herbivores with low-crowned teeth are predominantly browsers and species with high-crowned teeth are predominantly grazers." This is not a new inference, however, as the Russian paleontologist and contemporary/colleague of Darwin, Vladimir Onufryevich Kovalevsky, had proposed a connection between hypsodonty and grazing as early as 1873. The fragment -therium is derived from the Greek therion (beast), simply referencing the fact that this is an animal. The specific epithet of the type, sibiricum, is in reference to the Siberian origin of the jaw.

Heinrich Harder, 1920

Over the decades many things changed surrounding the knowledge of Elasmotherium, including the addition of many more complete, but still fragmentary, specimens of all three species of the genus. The shape of the body and the giant horn took shape. The horn, easily explaining some forms of unicorn legends (though of course these are probably not localized to any one region or type of animal), was enormous and, despite recognizable placement on the skull, was often illustrated in a much more unicorn-like posture. Newer images, we will see during the week, have become much more reminiscent of extant rhinoceroses but older images were significantly horse-like in appearance. This could be partially because of the then emerging knowledge of the relationships between horses and rhinoceroses or it could also be because the body simply appeared that way to earlier illustrators and scientists. Either way, the first full body illustrations were rather interesting because of the horse-rhinoceros cross over of the body shape.

Fischer, J. (1809). "21. Sur L'Elasmotherium et le Trogontothérium". "Memoires de la Société Impériale des Naturalistes de Moscou". Tome II. Moscou: Imprimerie de l'Université Impériale. p. 255. 

MacFadden, Bruce J. 2000. "Origin and evolution of the grazing guild in Cenozoic New World terrestrial mammals". In Sues, Hans-Dieter. Evolution of Herbivory in Terrestrial Vertebrates: Perspectives from the Fossil Record. Cambridge: Cambridge University Press. pp. 223–244