Re: Respiratory Conchae

["Scott Hartman" <scott_hartman@hotmail.com>]

One other point that needs to be raised about RT research:  We really are 
not sure how strong the correlation between RTs and endothermy should be in 
non-mammals.  RTs are all about water conservation, and while water 
conservation is obviously important to all animals, it is particularily 
important in mammals.  I'm sure most of the listers already know about the 
uric acid vs. urea dicotomy, so rather than pissing into the wind (sorry, 
couldn't resist) on that subject, I'll point out the results:  Birds, often 
one with substantially higher BMRs than eutherian mammals, usually have much 
smaller and simpler RTs than said mammals.  Despite this rather obvious fact 
(you can see examples in many papers by Ruben et al.), no one has bothered 
to test the effect of RT loss or damage on avians.  As a result we can't 
quantify the importance of RTs in non-mammals.  We don't even know how RT 
surface area scales (if it does) animal mass.  We don't really know piss 
about RTs in the larger evolutionary view.
   RTs may be important in non-mammals, since it appears that many 
dinosaurs may have had attachments for RTs or their equivalents.  But how 
important, no one can really say for now.

Just my two cents...

Scott
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