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Re: book reviews, parsimony and some loose ends



In a message dated 96-10-25 13:42:52 EDT, mrowe@indiana.edu (Mickey P. Rowe)
writes:

> In any case, since there clearly are quadrupeds that grasp prey with
> their forelimbs, and since it's not that hard to imagine an ambush
> predator experiencing selection for bipedality in order to make the
> forelimbs more efficient grasping organs, I don't know why you'd
> have such a problem with "b" either.

If bipedality were so easily evolved, and for such seemingly trivial reasons,
then why aren't there more bipedal mammals than just humans and kangaroos
(and a few lightweight scansorial rodents)? I maintain that bipedality in
dinosaurs is an >abnormal vertebrate stance< necessitated by the evolution of
the forelimbs into wings, during which the forelimbs lost their portal
locomotor function. BADD theory simply says that bipedality happens from time
to time, that it happened to dinosaurs, and that this allowed(?) their
forelimbs to become wings (why wings?). BADD is irritatingly _ad hoc_ about
this, as it is about most other functional aspects of dinosaur evolution.