Rauhut's Thesis (my thoughts on some parts)

["Rob Gay" <rob_redwing@hotmail.com>]

In response to several things about Rauhut's thesis (which I would like a
copy of, btw, whomever offered)

> Welles (1976, 1984) and later Welles & Madsen (2000) to surmise that
*Dilophosaurus* had a mobile premaxilla, which is certainly possible, though
in agreement with Rowe (1989) I would say that the mobile premaxilla does
not make the jaw "weak" but can in fact imply great structural capability.<
While the idea of a mobile premax is certainly very cool, to say the least,
at least in _Dilophosaurus_, it is not likely (nor in any coelophysoid
dinosaur, IMNSHO). Internally, the premax is firmly braced to the maxilla by
a very large ridge of bone, that would seem to entirely preclude movement in
the snout.


> I can't judge that, but these characters sound pretty weak, IMHO.<
I would agree. Putting an animal that is apparently disputed to be
dinosaurian or not into a fairly well established group on the basis of two
characters sounds pretty weak to myself as well. However, I am not very
familiar (yet!) with this beast, so I may have something more to say on this
later.

On the placement of _Dilophosaurus_ and _Segisaurus_:
I actually agree with his placement of _Dilophosaurus_ outside of the usual
coelophysid tree. In fact, this agrees nicely with my (albeit limited)
analysis that put _Dilophosaurus_ as a sister taxa to this group. I also
find it interesting that _Segisaurus_ ends up as a basal coelophysid...but
maybe that's me just being me.

> <I'm already waiting that Dryptosaurus becomes a ceratosaur...><
Wait and see, coelophysoids are actually the closest ancestor to
birds...oy...someone help, it's getting late.
Peace,
Rob

Student of Geology
Northern Arizona University
Biological Science Tech
Manti-La Sal National Forest
AIM: TarryAGoat
http://www.geocities.com/elvisimposter/dinopics.html
http://www.cafepress.com/RobsDinos
"A _Coelophysis_ with feathers?"

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