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Re: New AVES definition refined (more testable?)
> PRIMARY DEFINITION of Class Aves sensu lato (proposed):
> Theropods possessing both [...]
And all descendants of the first theropod that had this combination? That
way you'd approach a PhyloCode-style apomorphy-based definition. :-)
> SUPPORTIVE CHARACTERS:
> (1) Enlarged sternum articulating with more than 2 pairs of ribs.
> note that sternal anterior margin is apparently often slotted for
> (and said coracoids sharply reflexed).
Why not simply "preserved, discovered and described sternum"? :-> That of
*Pelicanimimus*, the only known ornithomimosaurian one AFAIK, is said to be
pretty big, too.
> (4) Laterosphenoid head small, and snovial joint small or absent
What's that? I barely know what the laterosphenoid is :-)
> (6) Preacetabular blade of ilium dorsoventrally elongated (also in
> segnosaurians, but it is distinctively expanded laterally).
> (10) Often possess ossified uncinate processes.
Relatively often preserve uncinate processes. Just like Willo, crocs? and
> (12) Most Aves (but caenagnathiforms are primitive in this respect)
> have retroversion of pubes to varying degrees (retroversion in
> probably occurred in parallel--i.e. a mild case of convergence).
Well, the pubis of *Archaeopteryx* is vertical as in *Allosaurus*...
> (13) The fused distal carpal element has often fused to the
> (forming a carpometacarpus). Apparently arose at least twice in Class
> sensu lato.
Who out of (*Sapeornis* + Pygostylia), *Avimimus* and possibly
Alvarezsauridae has this?