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Re: Archaeopteryx flight
In a message dated 9/4/01 2:02:35 PM EST, dino.hunter@home.com writes:
<< Important point here, "hands-free". If they still used their hands while
climbing then they wouldn't need a reversed hallux. >>
Which, naturally, is why Dilophosaurus-grade theropods retained an opposable
pollex while in the process of acquiring the opposable hallux. 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). As
the forelimb became more winglike, the feet took over more of the climbing
functions that originally were shared by both sets of limbs.