Re: Wilkinson's new pterosaur paper

[Michael Habib <mhabib5@jhmi.edu>]

> The two wing configurations 1) wingtip to elbow and 2) wingtip to 
> thigh are fundamentally different. The first has its origin distally, 
> like a bird. The other proximally, like a flying squirrel. You cannot 
> have one AND the other in the same clade.

I'm not sure I understand you.  The question, as I see it, is what the 
inboard wing looked like.  The outboard wing is obviously a narrow 
chord structure in those species for whom we have impressions, but the 
inboard wing isn't known for certain.  Now, I agree with the assertion 
that most were probably free of the hind limb, especially in 
large-bodied pterosaurs, but that is not at all certain.

I don't quite understand what you mean by "wingtip to elbow".  The wing 
has to attach somewhere proximally.  I suspect that it attached near 
the anterior edge of the ilium in most large pterosaurs, and perhaps to 
the thigh in some others (and perhaps the ankle in a few 
forest-dwelling taxa).  I see no reason why multiple attach points 
cannot exist in the same clade.  It would simply mean "sliding" the 
proximal insertion point developmentally.  Hardly seems impossible, or 
even improbable.

Cheers,

--Mike H.


Michael Habib, M.S.
PhD. Candidate
Center for Functional Anatomy and Evolution
Johns Hopkins School of Medicine
1830 E. Monument Street
Baltimore, MD 21205
(443) 280 0181
habib@jhmi.edu