RE: Archaeopteryx flight

["Tim Williams" <twilliams_alpha@hotmail.com>]

Tracy Ford wrote:

> Important point here, "hands-free". If they still used their hands while
> climbing then they wouldn't need a reversed hallux.

Depends what you mean by "need".  Some opposability in the pedal digits 
would have been an aid in clambering among branches, insofar as it must have 
helped the prehensile manus in the theropod's quadrupedal locomotion among 
branches.  The abilities suggested by the pes of _Archaeopteryx_ and 
_Microraptor_ probably did not qualify as true perching - but it was on the 
path toward it.


Dinogeorge wrote:

> In
> ceratosaurs, the hallux is not as distal and not as retroverted as in >the 
> more derived tetanuran theropods--in which the pollex is no longer 
> >opposable and the hand had completely lost its fourth digit (metacarpal 
> included).

No longer opposable!!  Hang on (excuse the appalling pun).  What *specific* 
features of the pollex of tetanurans make it *less* capable of converging on 
the palm or the other two manus digits?


Tim


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