Re: was: Pterosaur.net now: pteroid

[David Marjanovic <david.marjanovic@gmx.at>]

>  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.