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Re: Dinosaurs to birds



In a message dated 1/23/99 1:56:13 PM EST, jbois@umd5.umd.edu writes:

<< But speciations, extinctions (often the flip side of the speciation coin),
 adaptive radiations, morphologies are all _directional_ not chaotic or
 random. >>

No, speciation occurs randomly. The directionality comes later, the result of
differential culling through extinction of less well-adapted individuals. If
there were no random component to speciation, species diversity would be far
less than it is.