At 06:43 PM 09/10/01 -0700, Michael de Sosa wrote:
David M. wrote:
>Does this mean grasping feet (at least a reversed hallux) are necessary for
>vertical running?
Not in such birds as woodpeckers, which use the stiffened tail as a
brace. Some woodpeckers actually rotate the hallux outward so it is
directed laterally, not vertically, while climbing; the effect is rather
like a lineman climbing a pole with a safety belt, except that the bird's
feet correspond to the belt and the tail to the lineman's legs.
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Ronald I. Orenstein Phone: (905) 820-7886
International Wildlife Coalition Fax/Modem: (905) 569-0116
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