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Re: Physiological Adaptations of the Dinosauria (long)



Allow me to interject for a moment here:
Because (to my knowledge) ?D. sinensis has the largest nasolacrimal
crest among coelophysoids (with the possible exception of D. wetherilli)<
From what I have seen (pictures and drawings) of _D. sinensis_, the crests
are apx. the same size as that of _D. wetherilli_ (a little bigger, but negligible). However, they appear to be much thicker than _D. wetherilli_, and I would think that you would want thin vanes if you were going to be using this structure as a radiator. But if we were going to discuss crest vs. total skull size, I would think that _Syntarsus kayentakatae_ would have the largest proprtional crest, being apx. 40% of the length and 21% of the height of the skull, plus having an antobrital fenestra almost as long and twice as tall. And, this is almost contra your argument, but most coelophysoids have >huge< antorbital fenestrae, covering in some cases almost 45% of the length of the skull.

which when acting as a radiator panel for the superior nasal artery,<
In coelophysoids that had crests, most of the crest was composed of the lacrimal, or even a seprate bone, as posited by Welles (1984), so positioning might be questionable for this function.

would give it a higher condensation rate than, say, a similarly-sized E. baldwini.<
This is a hypothetical _Eucoelophysis_ that you speak of, right? Because _E. baldwini_ wasn't similarly-sized.

If you took a measurement of the istopic ratio for the crest itself and the base of the antorbital fossa, it should indicate how much heat was being lost, and whether condensation was really possible in this animal.<
I don't follow here. Both of the areas mentioned here are what you propose for heat exchangers, so you have no neutral ground. You'd also need to take a sample from some place like the illium or the scapula to see if there was a difference.
Peace,
Rob


Student of Geology
Northern Arizona University
P.O. Box 20840
Flagstaff, Az. 86011
AIM: TarryAGoat
"A _Coelophysis_ with feathers?"

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