The Joys of the Ornithomimids
A number of team members at Everything Dinosaur are involved in proof reading information to be used in a forthcoming dinosaur themed event. One of the dinosaurs featured is an Ornithomimus (pronounced or-ni-tho-mime-us) and we have been asked to check the anatomical description. This has led to some lively debate amongst us. We were divided on how best to describe the forelimbs of Ornithomimus, the name means “bird mimic”. With many advanced Ornithomimids from Late Cretaceous North America and Asia, the length of the limbs did vary between genera.
For instance, when looking at overall body proportions the hind legs are long in Ornithomimus, but not as long in proportion to the body of Struthiomimus; for example. Scientists are confident that these animals were cursorial and fast runners too, but when comparing body sizes between Ornithomimids confusion can arise, particularly when assessing length and size of forelimbs.
With Ornithomimus, at least three species co-existed together in North America. Slight differences in skull shape have proved to be the main diagnostic feature helping to distinguish O. antiquus from O. edmontonicus for example. Despite being very well known, (at least in the public’s perception), taxonomic relationships between various genera are still not well understood – hence our debate this morning.