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Re: Reversed Hallux in Theropods: a query



In a message dated 95-11-24 19:04:20 EST, ornstn@inforamp.net (Ronald
Orenstein) writes:

>Yet these species are almost if not entirely terrestrial.
>So are some species of woodpecker.  Yes, surely these birds evolved from
>arboreal ancestors, but they are perfectly able to get about on the ground.

Heh, heh! I was exaggerating for effect, of course! Clearly, all dino-birds
and birds with big, retroverted halluces could get around on the ground! But
in a lineage that _adapts_ to a ground-dwelling existence, no longer uses the
big hallux for perching, and finds no other uses for it (such as grasping
prey, as in eagles), the hallux fairly quickly becomes relatively smaller.
Well, perhaps the best way to put this in the case of known theropods is that
the rest of the foot _got bigger_, leaving the hallux behind.