Re: Rauhut's Thesis

["Mickey Mortimer" <Mickey_Mortimer11@msn.com>]

Rob Gay wrote-


> What is the relationship of _Monolophosaurus_ to ceratosaurs anyways?

The same as Allosaurus to ceratosaurs.  Monolophosaurus has been placed in
the Carnosauria by all phylogenetic analyses so far (Holtz 1996, 2000;
Sereno 1994, 1996, 1999; Rauhut 2000).

Randall Irmis wrote-

> I'd have to disagree with you here.  If D. sinensis is indeed a
ceratosaur,
> then I would have a hard time beleiving that the crest is convergent.

But it's not neccessarily a ceratosaur.  The opisthocoelous cervicals are
unlike coelophysoids and Dilophosaurus, only a single pair of cervical
pleurocoels is mentioned, the anterior dorsals are opisthocoelous, the
scapula is reported to be narrow and long, the femoral head is not
downturned, etc..  Of course further examination could show ceratosaurian,
or at least non-tetanurine characters, as the description was very short.
Can anyone find any synapomorphies that would help pin down its position?
Regarding the crest, Syntarsus kayentakatae has a very similar crest to
Dilophosaurus as well, but it seen as a coelophysid.  If these taxa can
separately evolve such similar crests, why not Dilophosaurus and "D."
sinensis?

Mickey Mortimer