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Re: Terrestriality is a bias



In a message dated 6/11/00 9:45:28 PM EST, ornstn@home.com writes:

<< One of the problems we have in trying to assess this whole issue is that 
we 
 have no real modern analogue to an arboreal bird ancestor - that is, a 
 primitively flightless arboreal biped >>

Don't think the ultimate bird-theropod ancestor was obligatorily bipedal; it 
was likely a semi-erect climbing quadruped. Bipedality evolved >along with< 
the evolution of the forelimb into the wing, and whenever a theropod lineage 
split off into terrestrial cursoriality, the forelimb was useless for 
locomotion and simply vestigialized.