Re: Dimorphic Dilophosaurs

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

Steve  Brusatte wrote:
> I was recently allerted of a paper discussing sexual dimorphism in 
> Dilophosaurus.  Could anybody give me a ref, and, if possible, an abstract 
> or short summary (because I have a hard time finding many of these papers 
> in the middle of Illinois farm country).<

To which Jordan Mallon replied:
> Might this have anything to do with the whole _D. wetherilli_/_D.
breedorum_ "controversy"?  I understand many people consider them to be 
sexual dimorphs.<

Alow me to step in here. While HP Greg Paul suggests sexual dimorphism in 
his excelent book, PDW, I must disagree. While I may by no means be a Ph.D., 
I do have some experience with this animal. In fact, a project that I 
undertook was trying to compare potential sexual dimorphism in _Coelophysis 
bauri_ and _Syntarsus rhodesiensis_ to _D. wetherilli_. I measured, 
compared, looked at many actual specimens, ploted charts, ran ratios. And I 
wrote a paper for my paleo class. My conclusion; all variation seen within 
_D. wetherilli_ can be explained by individual variation and ontogeny. The 
plot is a straight line, unlike what was found by Raath in _S. 
rhodesiensis_. There is no evidence that I have seen that _D. wetherilli_ 
exhibits sexual dimorphism (though, I must say, I think it would be cool if 
it did). So, there you have it. Although I may not usually have much to 
contribute to some of the topics on this list, this is one thing that I do 
have some knowledge about. If anyone wants a copy of my paper, by the way, 
feel free to contact me, and I'll e-mail them a copy.
Peace,
Rob

Student of Geology
Northern Arizona University
P.O. Box 20840
Flagstaff, Az. 86011
AIM: TarryAGoat
"A _Coelophysis_ with feathers?"

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