Re: thoughts on Pterasaur feet

[Adam Yates <zooamy@zoo.latrobe.edu.au>]

On Tue, 1 Apr 1997, Bettyc wrote:

> Bettyc wrote:
> I think this means a separate structure entirely-and without any
> evidence of a large membrane at this long toe linking it to the wing,
> likely there wasn't one.  I think it was it's own structure that echoed
> the shape of the wing, perhaps with a (vestigal?) membrane of skinflap
> as depicted as in Reichel's reconstruction.
> -- 

Interesting thought, perhaps it was a non functionalgenetic  consequence of 
digit 
elongation in the forelimb. Much like the enlarged but unused tibial 
sesamoid of Pandas (the homologous forelimb bone, the radial sesamoid, is 
enlarged for use as a "thumb" - see Gould's "The pandas thumb"). For this 
to be true though, the didgits would have to be homologous ie, both 
fourth and fifth, unfortunately I don't think this is the case.

cheers 

Adam Yates