Subject: [Tweeters] avian polydactyly question
Date: Sep 23 08:57:22 2008
From: Devorah Bennu - birdologist at yahoo.com


hey tweeties,

a pal who both keeps birds and who is a birder asked me about avian polydactyly after having encountered several instances of it (one in captivity at a local bird store and one as an wild rescued chick). i assume this condition exists in birds just as it does in humans, but i was curious if any of you have encountered this yourselves? since it is a dominant trait (in humans), i wonder what selective pressures keep it from becoming more common among birds? if you have any comments or thoughts about this, i would be interested to read them and to pass them along to my bird pal.

GrrlScientist
Devorah
http://scienceblogs.com/grrlscientist/
Roosting high up a tree somewhere in Central Park, NYC