Re: Theories on the extinction of dinosaurs

[John Bois <jbois@umd5.umd.edu>]

On Fri, 19 Nov 1999 Philidor11@aol.com wrote:

> Is it possible that this is one of those insoluble mysteries?  

Yes.  Absolutely.  But for me that is not the point.  Let me use a similar
"mystery" as an example.  I forget who it was who claimed that the lack of
viviparity in birds _needed_ an explanation; that the inability to
provide a plausible hypothesis for this phenomenon was an embarrassement
for evolutionary theory.  Now, I don't know how those particular
explanations are coming along, but I feel dinosaur extinction is
analagous.  We (you, us) have not yet provided a model which the majority
buys into.  For many (most) paleontologists, the bolide by itself doesn't
cut it.  And for me, _all_ physical causative agents are problematical:
dinosaurs were living things which had survived plenty of similar
challenges and survived.  Plenty of other, similar living things survived
the K/T.  What, then, was the targeting mechanism such that, among
vertebrates, non-avian dinosaurs were _selected_ against?  Providing a
plausible explanation for this (even as an hypothesis) is a
challenge we must face.