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Re: Revised *classification* of Aves



Ken Kinman wrote-

> And since most birds do not "manuraptor" their food, it is
> certainly a totally inappropriate name for the entire Class anyway.  What
> was once called Aves is virtually identical to the cladistic Avialae
(which
> begins at Rahonavis or Archaeopterygidae; i.e. node 6 or 7 in Order
> Archaeopterygiformes below).

Appropriateness of names is irrelevant, blah blah blah...
Avialae _could_ contain more than just Aves, Rahonavis and Microraptor (both
of which might be avians).  It may include Sinornithosaurus, troodontids,
alvarezsaurids and/or Avimimus.

> Plesion Alvarezsaurus is joining segnosauria as being preliminarily
> ejected from Class Aves.  If there is any really good evidence that it
> belongs in Class Aves, I would like to hear of it.  Alvarezsaurus appears
to
> be an ornithomime-segnosaurian "grade" form, along with Coelurus.

Okay, that's it.   WHY?
NO ONE has EVER placed Alvarezsaurus close to ANYTHING except for
Patagonykus and mononykines.  Bonaparte (1991) didn't, but other
alvarezsaurids weren't recognized yet.  He just put it in Alvarezsauria
among theropods, not knowing what it was related to specifically.  Why won't
you believe the following list of characters connecting Alvarezsaurus to
Patagonykus and Mononykinae?

- short and low cervical neural spines (Novas, 1996)
- rudimentary cervical epipophyses (Novas, 1997)
- procoelous sacral vertebrae (Novas, 1996)
- posterior sacral centra transversely compressed (Novas, 1996)
- procoelous caudal vertebrae (Chiappe et al., 1996)
- first caudal centrum keeled ventrally (Chiappe et al., 1998)
- elongate proximal chevrons (Novas, 1996)
- stout, robust manual ungual I, with quadrangular articular surface (Novas,
1996)
- m. cuppedicus fossa of ilium absent (Novas, 1996)
- supracetabular crest ends above acetabulum (Novas, 1996)
- brevis shelf caudolaterally oriented and medial flange ventrally curved
(Novas, 1996)
- pubic peduncle anteroventrally projected (Novas, 1996)
- slender pubic peduncle (Novas, 1996)

Sure some have problems, but in general the list seems good to me.  As far
as I know, EVERYONE (and I mean everyone, Holtz, Norell, Sereno, Martin,
Chiappe, etc.) agrees the clade is monophyletic.

> 2  Parvicursoridae
> 3  Mononykidae

Dividing these is pointless.  They are very similar, and nobody's tried to
see where Shuvuuia or the other mononykines fit compared to them.

>         B  Iberomesornithidae
>        15  Enantiornithidae
>         B  Gobipterygidae

Already commented on the futility of dividing "enantiornithines" at this
point.

Mickey Mortimer