RE: Large UK "velociraptorine teeth"

["Tim Williams" <twilliams_alpha@hotmail.com>]

Ralph Miller wrote:

> If this large theropod was indeed a dromaeosaur, and if it was a
> contemporary of Liaoning dromaeosaurs, then this suggests (to me) that
> dromaeosaurs must have originated much earlier than 125 million years ago 
> to
> have produced such diversity.

This is supported by the discovery of putative dromaeosaurid teeth from the 
Late Jurassic (e.g., Guimarota).  Also, the sister taxon relationship 
between deinonychosaurs and birds, combined with the presence of an 
undoubted bird (_Archaeopteryx_) in the Late Jurassic, shows that the 
Deinonychosauria and Aves had split before then.  (Unless, as some folks 
suggest, deinonychosaurs are actually more derived than _Archaeopteryx_).

The range of adult body sizes across the dromaeosaur clade is certainly 
impressive.  Still, it pales in comparison to the range we see in the 
deinonychosaurs' sister group!


Tim

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