STL Science Center

STL Science Center

12 November 2013

Looking at Brains and Heads

There are quite a few studies of Alioramus out there to be read. There is a little for everyone in fact. There are studies on osteology of Alioramus specimens out there. The study referenced in this paper even questions the validity of A. altai based on the fact that it appears to represent a younger individual that may in fact only have ontogenetic differences separating it and A. remotus. Additionally, this paper makes note of, and reinforces, the point made here earlier that the jaw, unique amongst Tyrannosaurids, was probably not used in a typical tyrannosaur method of excising large chunks of food for swallowing. An alternative is not mentioned specifically, but instead it is proposed that that mode of feeding may in fact be present in adults of the genus; unfortunately only individuals deemed to be immature have been discovered.

A second paper of interest examines the braincase, via CT scanning, and describes the structure in a highly detailed manner. 21 characters from this structure were used in redefining the tyrannosaur phylogeny recently and all of these characters are addressed and discussed in this paper. It is certainly well worth the read if one has the time. Interest in a somewhat separate area of tyrannosaur phylogeny is represented in this PLOS ONE paper that expounds upon the hypothesis that the rise and fall of  tyrannosaur lines can be used to parallel the rise and fall of the Cretaceous oceans. Much of this paper discusses Larimidia (the western half of North America) and the Western Interior Seaway, but there is also mention of the Asian tyrannosaur families as well. Of these North American tyrannosaurs, those from Utah are most highly discussed and the parallels of the ocean habitats of the Cretaceous are drawn from these animals. Despite not being of particular central interest to this paper, Alioramus is a tyrannosaur and, supposedly at least, the same conclusions ought to be able to be drawn by studying Alioramus in a similar fashion.

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