Re: Patagium attachment Was: Re: Pterosaur.net

["jrc" <jrccea@bellsouth.net>]

I'm not aware of any preserved membrane for which the trailing edge of the 
membrane in the vicinity of the elbow is located more than about 45% of  the 
length of the humerus behind the elbow.  As Mike points out, that has no 
implications whatever for the extent of the hindlimb attachment, which may 
be quite variable between species, and even possibly non-existant in some 
(I'm not pushing that latter scenario -- just pointing out that the fossil 
materials don't yet exclude it).  Personally, I suspect that hindlimb 
attachments may have been quite variable both between species and across the 
eons -- but, I do not see any current evidence for broad wings.  The narrow 
wing implies a fairly tight radius for the trailing edge of the wing 
membrane in the vicinity of the elbow as the membrane fillets into the 
hindlimb and also weakly implies that the fillet was not normally heavily 
loaded.
JimC

----- Original Message ----- 
From: "Mike Habib" <habib@jhmi.edu>
To: <davidpeters@att.net>
Cc: "Mark Witton" <Mark.Witton@port.ac.uk>; "jrc" <jrccea@bellsouth.net>; 
<dinosaur@usc.edu>; "Mike Hanson" <mhanson54@comcast.net>
Sent: Tuesday, January 19, 2010 11:50 AM
Subject: Re: Patagium attachment Was: Re: Pterosaur.net


> On Jan 19, 2010, at 10:27 AM, David Peters wrote:
>
> > It would probably help in understanding. Jim, if this model wing of 
> > yours is a deep wing attached to the ankles or a shallow wing  attached 
> > at mid thigh. I'm guessing the former because you  mentioned, "Increasing 
> > the inner wing tension of the retracted wings  during a dive by use of 
> > hindlimb positioning..."
>
> Just worth noting here that a wing can be attached to the ankles and 
> still be primarily narrow in its chord through most of its length. 
> Therefore presuming a broad or narrow overall wing, based only on 
> attachment, is a error.  The outboard wing in every well preserved 
> brachiopatagium is narrow.  At the same time, several specimens seem  to 
> show some hindlimb attachment - the most simple explanation is  therefore 
> that the attachment was broad but the wing was narrow.
>
> Cheers,
>
> --Mike
>
>
> Michael Habib
> Assistant Professor of Biology
> Chatham University
> Woodland Road, Pittsburgh PA  15232
> Buhl Hall, Room 226A
> mhabib@chatham.edu
> (443) 280-0181
>
>
>
> >