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Re: PAGATIA DO NOT MEAN VOLANT ANCESTRY
In a message dated 8/23/98 3:07:49 PM, PTJN@aol.com wrote:
<<The fossil record shows that the fused carpometacarpus evolved after powered
flight (Archaeopteryx, Eoalulavis and Confuciusornis for example). Given the
way the Patagialis muscles and the carpometacarpus function together, my
personal feeling is that the propatagia probably did as well--although I'm
still trying to work the sequencing out in my own mind.>>
Incredible. Just when I thought brooding-came-first had run out of ways to
explain the evolution of the wing, along comes the above. Made me run back to
my copy of "Dinosaurs of the Flaming Cliffs," where there is a highly accurate
full life restoration of Oviraptor on its nest by Mick Ellison (p. 306)
wherein the animal is placed on the eggs EXACTLY as the fossil dictates (right
down to the supinated hand). Mark Orsen and I, in our Dinofest '98 paper,
have used this illustration, which shows a naked, scaly skinned Oviraptor, as
a way to show how extensively the eggs are exposed without feathers. Now I
have gone back to note the possible role of the propatagium, and voila.
Here's the point: if primary (hand) and secondary (forerarm) feathers
existed on Oviraptor, they would have covered all of the eggs EXCEPT -- those
that would be covered by a propatagium. Cool.
Now I'm wondering: If even the propatagium can be explained by a need for
theropods to cover their nests, what bird-wing feature doesn't have a possible
origin among brooding theropods?