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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.
Also
> note that sternal anterior margin is apparently often slotted for
coracoids
> (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).

Dorsoventrally? Really?

>      (10) Often possess ossified uncinate processes.

Relatively often preserve uncinate processes. Just like Willo, crocs? and
*Sphenodon*.

>      (12) Most Aves (but caenagnathiforms are primitive in this respect)
> have retroversion of pubes to varying degrees (retroversion in
segnosaurians
> 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
metacarpals
> (forming a carpometacarpus).  Apparently arose at least twice in Class
Aves
> sensu lato.

Who out of (*Sapeornis* + Pygostylia), *Avimimus* and possibly
Alvarezsauridae has this?