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Re: New Ruben et al. dinosaur physiology reference

On Tue, Jul 08, 2003 at 01:40:35PM -0400, Thomas R. Holtz, Jr. scripsit:
> The URL for the issue is:
> http://www.journals.uchicago.edu/PBZ/journal/contents/v76n2.html
> Physiological and Biochemical Zoology 76(2):141-164. 2003.  INVITED
> Respiratory and Reproductive Paleophysiology of Dinosaurs and Early
> Birds
> John A. Ruben, Terry D. Jones, Nicholas R. Geist,
> Studies such as these demonstrate that although dinosaurs and early
> birds were likely to have been homeothermic, the absence of nasal
> respiratory turbinates in these animals indicates that they were
> likely to have maintained reptile-like (ectothermic) metabolic rates 

Is there -- in light of the extant tachymetabolic automatic endotherms
with minimal or no nasal respirator turbinates -- something supporting
this conclusion, or is it (for those with access to the paper) being
taken as an extremely conservative position to strengthen claims of
territoriality and mobility?

I'm bothered by it becuase nasal turbinates are primarily a mechanism
for moisture retention and heat exchange, and it's hard to see them as
the only way to do that, particularly given the probable basal nature of
the dinosaurian uniflow airsack and lung system, so I'm seeing this as
an unjustifiably strong conclusion.

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