|A reconstruction of Thescelosaurus assiniboiensis (top) and |
the positions of the bones within the skeleton (bottom)
The 66 million year old bones were first collected in 1968 in the remote Frenchman River Valley near Eastend, Saskatchewan, Canada. They consisted of two nearly complete legs, a partial ribcage and fragments of the tail and skull. Apart from some articulation of the joints in the legs, the specimen was rather drab and was stored away until Caleb Brown, a master's student at the University of Calgary, investigated the ancient bones for his thesis. He quickly realised that the bones were not from any documented species of Thescelosaurus.
The skeleton was far smaller than other specimens. While it could be argued that it was simply a juvenile form, details pertaining to its bone morphology suggest otherwise. 'It is small, but there are features in the cranium, the back end of the skull, and a few features in the pelvis that are quite distinct amongst all other known species of Thescelosaurus' said Tim Tokaryk, Head of Palaeontology at the Royal Saskatchewan Museum. It has been named Thescelosaurus assiniboiensis.
Tokaryk compared it to white tail deer in terms of size. 'That's pretty small for a dinosaur in general. I mean T. Rex, which this thing would have had to avoid, was quite large. We know there were small dinosaurs around at that time because we found fragments, we find teeth and such like that. But to find a partial skeleton of one individual, that makes it interesting and also makes it more useful to be able to identify it as a new species or a species in general.'