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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.