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Re: dinosaur anatomy



JSeward123@aol.com wrote:
> In "Science," (8-30-96, p.1204), it was revealed that Dromaeosaurus
lacked
> nasal turbinates. What about Archaeopteryx? Has it been posssible to see
if he
> had them?

Perhaps others will supply more complete information on this topic, but I
recall that the _Discover_ magazine report on respiratory turbinals in
extant birds and mammals (but apparently not indicated in the fossil
specimens of those dinosaur skulls studied) indicated that the Oregon team
had concluded that evidence for respiratory turbinals (and hence,
endothermy)  in prehistoric birds dated back no earlier than 70 million
years ago.  I find it most perplexing to conceive of feathered, flying
birds evolving and radiating for over 80 million years, and yet having (in
the opinion of these researchers) ectothermic metabolisms for all this
time.  This was what I found most unconvincing in the conclusions of these
papers.

Ralph Miller III <gbabcock@best.com>