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Re: Dinosaurs to birds
In a message dated 1/21/99 6:36:24 PM EST, Dwight.Stewart@VLSI.com writes:
<< Or (somewhat alternately): birds were sufficiently derived (in some way) to
survive the KT extinction. This is whether a bolide was the cause or just a
contributor. Some evolutionary adaptation that was present in Cretaceous
birds, but not present in Cretaceous non-avian dinosaurs gave birds an edge
(in this case). >>
Could also have been sheer luck. We have no good handle on bird diversity
during the Cretaceous, but if it was (as I think) quite high, then most of the
birds were killed off, too, and the post-Cretaceous bird radiation would have
stemmed from just a few (say 40-50) survivor lineages (out of, say, 500-1000).