RE: Rauhut's Thesis

[rbi <rbi@dana.ucc.nau.edu>]

>===== Original Message From rob_redwing@hotmail.com =====
>>I dont quite understand what your saying.  The crest in D. wetherilli and
>>"D." sinensis are formed by the same bones.<
>Yes. And those are the bones that it would make sense to use, if forming two
>lateral ridges, regardless of anything else. But, the morphology is very
>different between the two (see my earlier message). These results seem to be
>more the result of pressures selecting for two lateral ridges than of common
>ancestry (which HP Headden has expounded on).
>
>>Monolophosaurus has a crest that incorporates additional bones with quite a
>>different morphology.<
>Yes. But, its only singular, and more of a ridge than a crest. I'm not sure
>if this animal is very useful for comparisons in this case.

AAHHHH!!!  Your missing my point.  First, that differences are to be expected
between species and genera, therefore I am not surprised by the differences in
D. wetherilli and "D." sinensis.  The point about Monolophosaurus is that it
IS different, and therefore is a clear example of convergence, whereas the two
species of Dilophosaurus are not.

We can go on arguing this forever, but that is useless.  What I am putting
forth is just a hypothesis, that is all.  I think nothing can be settled until
a detailed description of "Dilophosaurus" sinensis is done, and we all can at
the very least examine accurate illustrations and photos of the whole skeleton
and individual cranial elements.

Regards,
Randall Irmis