RE: Rauhut's Thesis

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

> Just because two genuses have very similar cranial ornamentation doesn't
> mean that the ornamentation is convergent.<
But it doesn't mean its not either.


> They could have a common ancestor with a dual crest, and therefore, the
> item is homologous.<
Possible, but cannot be tested at the moment.

> There is a particular gene that codes for a crest.  It is on in a species
> 1.  It gets turned off when 1 evolves species 2.  It then gets turned on
> again when species 2 evolves species 3.  Osteologically, this could be a
> convergent crest.<
This seems like a complicated process of reversals. I believe that the more
parsimonious answer would be that the crests evolved seperately, as opposed
to switching a gene off and on and off and on. I'm going to have to agree
with HP Mortimer on this one.

> >So, clear conclusion:
 >"Dilophosaurus" _sinensis_ is (IMNSHO) a ceratosaur, possibly a
 >coelophysoid, but not congeneric with _Dilophosaurus_.

Yes, yes it is.<
Now I'm confused. Are you saying it is a coelophysoid, or it is congeneric
with _Dilophosaurus_?
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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