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Re: was: Pterosaur.net now: pteroid



 Especially since it is a former centralia

One centrale, two centralia.

(Same, BTW, for _gastrale_. "Gastralium" is wrong.)

 Remember the rest of the wing is creating drag that is trying to
 overextend the elbow. That is a constant force while flying. The
 propatagium is the only thing that prevents that from happening, as
 in birds and bats. It's a passive organ.

Apart from the usual muscles, mammalian elbows cannot be disarticulated by overextension without breaking bone.

 Mark, think of this in mechanical terms.

 1. That fragile tip of the pteroid ain't gonna hold up if you put
 lateral stresses on it. It can only survive longitudinal stresses. 2.
 It's extremely difficult to put a kink in the middle of an object
 being pulled from both ends. It keeps rebounding to a straight line.
 That kink would be right at the tip of the pteroid. 3. There's no
 muscle strong enough to pull the pteroid ventrally with such a short
 lever arm originating at the articulation no matter what bone you'd
 like to articulate it on.

Someone should quantify these things.