Re: CROCODYLOMORPH ENDOTHERMY

[ornstn@inforamp.net (Ronald Orenstein)]

>>> Besides, how could they have out-competed therapsids (largely considered
to be
>> endotherms) if thecodonts were ectotherms?
>> 
>
>Exactly my point!  Gosh it's nice when people just spontaneously see 
>things your way!  :-)
>
>> Rob

I'm not convinced this is necessarily valid.  Large ectotherms can do quite
nicely vs mammals under some circumstances- giant monitors and
pristichampsid (?) crocs seem to have taken over the large-predator niche in
Australia despite the presence of marsupial carnivores up to the size of
Thylacinus and Thylacoleo.  Pythons seem to do OK in an endotherm-dominated
world, too.

And, of course, we don't know if the therapsids were endotherms, and many of
the big ones (eg gorgonopsians) died during the Permian mass extinction -
perhaps making way for the thecodonts?
--
Ronald I. Orenstein                           Phone: (905) 820-7886 (home)
International Wildlife Coalition              Fax/Modem: (905) 569-0116 (home)
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