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Re: (Hopefully not much more) cladobabble



On Fri, 21 Nov 1997 Dinogeorge@aol.com wrote:

> Speaking of which, we should explore the consequences for dinosaur-bird
> taxonomy >if< the recent paper in _Science_ on the numbering of the modern
> avian wing digits is II-IV rather than I-III is >true<. It would mean, for
> example, that modern birds lie on a different branch of the dinosaur family
> tree than _Archaeopteryx_, dromaeosaurids, and most if not all known
> theropods.

Would it really? I would think a more likely scenario is that all
tetanurines (including birds) had digits II-IV. The most basal neotheropod
would have had four digits. Ceratosaurs would be a definite monophyletic
group, sharing a reduced digit IV. Tetanurines would have lost digit I,
not IV, and thus not be derived from a ceratosaur-like ancestor.
Any problems with this?

Of course, I think it's more likely that the embryology studies are in
error.

--T. Mike Keesey
tkeese1@gl.umbc.edu
http://umbc.edu/~tkeese1 -- Dinosaur Web Pages