STL Science Center

STL Science Center

21 September 2011

Oh Canada!

As with many other findings of the early 20th Century, Dromaeosaurus was uncovered by Barnum Brown in Alberta, Canada's Dinosaur Provincial Park. Brown found a skull and mandible, hyoid bones, one first metacarpal and some metatarsals. Like in many other finds, this scant evidence became the holotype of an entirely new dinosaur. Skeptics abound when this happens, however, other skull and teeth fragments were found as the years progressed in both Canada and Montana, USA. In 1922 Brown co-authored a paper naming and describing Dromaeosaurus albertensis, which literally translates to "Running Lizard of Alberta," which is kind of catchy all on its own, with William Diller Matthew, a well known mammalian paleontologist who had been busy championing the idea that humans originated in Asia during much of his lifetime.

Time marched on and seven more species of Dromaeosaurus were named:
Dromaeosaurus laevifrons (Cope 1876) Matthew & Brown 1922; Dromaeosaurus? cristatus (Cope 1876) Matthew & Brown 1922; Dromaeosaurus? gracilis (Marsh 1888) Matthew & Brown 1922; Dromaeosaurus explanatus (Cope 1876) Kuhn 1939; Dromaeosaurus minutus (Marsh 1892) Russell 1972; Dromaeosaurus falculus (Cope 1876) Olshevsky 1979 and Dromaeosaurus mongoliensis (Barsbold 1983) Paul 1988.
What usually happens after a dinosaur naming fervor happened to the seven species of Dromaeosaurus as well. Today we recognize only one species of Dromaeosaurus, not to be confused with the multiple genera and species of Dromaeosaurids (11 subgroups with multiple genera and species) or Dromaeosaurines (3 genera with at least 3 species). In saying there is one species of Dromaeosaurus we are saying only one exists under the genus Dromaeosaurus. Despite being, for a long time, the best cranial evidence of any Dromaeosaurid, Dromaeosaurus skeletons, in part due to their lightweight nature, are relatively rare in their own home range, that being Alberta and Montana.

Small, lightweight bones have an unfortunate tendency to disappear while remains are being fossilized, however, the robust skull of Dromaeosaurus is often the major part of the animal found. and much can be determined by the strength and build of the jaws and other skull bones. Despite this "primitively" robust skull, as noted earlier, Dromaeosaurus owned and operated a very specific niche in the community as a small aggressive theropod hunter. Not bad for a little guy.

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