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Re: semilunate carpal



In a message dated 8/8/01 1:54:56 PM EST, twilliams_alpha@hotmail.com writes:

<< Velociraptorines and birds share a common ancestor, and that ancestor used 
the predatory stroke (sensu Gauthier and Padian) - the lunging, 
forward-and-downward motion of the forelimb and the inward movement of the 
manus. >>

You don't know this any more than I know that the common ancestor had a wing. 
We have no direct fossil evidence of the common ancestor, so it could have 
been either birdlike or velociraptorlike or both or neither. You are 
inferring the appearance of the common ancestor via your acceptance of the 
ground-up hypothesis of bird origins. To me, the simple mechanical reasons 
for discarding the ground-up hypothesis are sufficient, so the birdlike 
nature of the common ancestor is the favored hypothesis over the 
velociraptorlike nature.