Re: Aves and Mononykus

[dbensen <dbensen@gotnet.net>]

What are alvarezsaurids if they're not flightless birds?  If they're
ornithomimes, it seems they've gone through an awful lot of derivation to arrive
at a point that's pretty much the same what they started from.  (In other words,
they _look_ a lot like ornithomimes).
Generally, species split off from each other, and then evolve in different
directions, so as to avoid competition.  I guess to argue that view, one would
have to know what the alvarezsaurids used their arms for, to see if they really
did occupy a different niche from the ornithomimes.

Also.  There were alvarezsaurids in South America, right?  Were there any
ornithomimes there?

Dan