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Re: ptero endothermy



I have no doubt that the long ilium could accept the loads you're talking 
about, Jim, but the ilium did not get any longer relative to the hind leg in 
the jump from nonvolant to volant -- or thereafter. What did happen was a 
reduction of the torso length with the first pterosaur and Sharovipteryx. 

Ironically, the giant winged ornithocheirids had the smallest pelves. 

dp



But that hypothesis doesn't impact the fact that the ilia can help
provide area to accept wingloads that reach the torso, and that longer
length, or larger diameter can reduce the attachment stresses.  This
would seem to be true no matter what the origin of the wings might be.

david peters wrote:
> 
> (jrc) Longer ilia can also mean more area to help accept the wingroot loads
> into the torso.
> 
> (dp) ????? Except that the longer ilia preceded the wings by thousands of 
> >generations. And the wings appeared only distal to the elbows at first.