Re: BADD BCF

[Robert.J.Meyerson@uwrf.edu (Rob Meyerson)]

>The first question I would ask is, does this surface serve as an airfoil in
>extant birds (it's hard to tell, because it's covered with feathers)? The
>second question is, do the patagial tensor muscles help draw the wing back
>during a wingbeat? My guess is that the patagium is one of those features
>that evolved as an adjunct to gliding or powered flight, because it seems t=
oo
>restrictive for a strictly climbing or grasping forelimb.

Yes to your first question.  As a part of my Ornithology class, I dissected=
 a pigeon.  When you remove the feathers, there is a noticable airfoil shape=
 to the wing.

No to your second question.  The patagial muscles are a separate entity from=
 the biceps, which do serve to draw the wing back.

>A most interesting anatomical feature, by the way. I wonder whether
>dromaeosaurids and other maniraptorans retained one.

Assuming BCF is correct, I would have to say no, since it would probably be=
 incorporated into the biceps.  The patagial muscles force the arm to be=
 held in a perminant V, a major disadvantage for any predator (you would=
 have to explain the loss of the patagium in BCF, by the way).

Rob

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