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Re: Respiratory Conchae

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...

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