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Re: Faunal list (Was Re: Selective Extinction)

Chris Campbell wrote:
> Jonathon Woolf wrote:
> <Snip>
> > And one more factor that needs to be considered: in the Permian,
> > Triassic, and Cretaceous extinctions, among land vertebrates there was a
> > metabolic pattern to the survivors.  100% ectotherms like lizards and
> > crocs survived, though greatly diminished.  Highly endothermic animals
> > like mammals and birds survived, again with heavy losses.  Animals with
> > in-between metabolisms, like dinosaurs and dicynodont therapsids, got
> > the chop.  Again, that seems to be consistent with some sort of massive
> > climatic disruption.  Not a disruption of food supply -- endotherms need
> > more food than ectotherms -- but to something else.  And it had to be
> > global in its effects, because the extinctions are global.
> One small point here (well, a rather large one, actually): who says the
> extinctions were global?  We always hear that and say it, but as Donald
> Archibald points out in his article on the subject in the Padian/Currie
> encyclopedia we don't know that.  He mentions that out of 26 KT sites
> around the world some 26 are from the Western Interior of North
> America.  That's a really bad sample there; in fact, I'd say that and
> conclusions dealing with any sort of simultaneous extinction event are
> pretty suspect based on the lack of data globally.  We don't know
> extinctions were global or simulatneous, and this seems to be one of the
> most common errors made in extinction theories.

Maybe the majority of _land vertebrate_ sites are Western North America,
but it's by no means true that all K-T sites are WNA.  There are known
K-T strata in India -- the Deccan Traps.  There are known K-T strata in
Mongolia -- Keith Rigby claimed Paleocene dinosaurs from Mongolia a few
years ago.  There are plenty of marine K-T strata all along the Western
European coast -- Peter Ward has studied extinction patterns in
ammonites extensively in those European marine beds.  There's even some
good K-T strata in upland Italy -- remember that Alvarez first found the
famous iridium anomaly in clay samples from near Gubbio, Italy.  

> > Matter a'fact, it occurs to me that some sort of "reverse El Nino," a
> > massive cooling of tropical waters,  could have precisely those sorts of
> > effects.
> And, interestingly, this is entirely consistent with the regression
> theory and entirely inconsistent with the impact theory (which would
> presumably result in boiled/superheated waters).  It also accounts for
> the froggies and sharks, who are the real buggers for the impact
> theory.

Which is one reason I have strong doubts about the
apocalyptic-asteroid-impact theory.

-- JSW