Re: extinction

[Scott <HORTON@BCRSSU.AGR.CA>]

>Disease is an especially interesting one; since, as you say, you have
>not yet read _Hereses_ you will be unaware that there are documented
>cases in recent times of just such a disease-driven extinction event,
>although somewhat minor in scope.  (I don't have the book with me, else
>I would cite.)

  I finished reading _THE_DINOSAUR_HERESIES_ since I originally posted that
note. I don't recall him documenting any disease-driven extinctions, but I'll
look at the book again. I was unconvinced by Bakker's arguments on extinction,
despite finding the remainder of his book very convincing re: warm-bloodedness,
etc.

>The point Bakker makes is not that a single dread killer disease wiped
>out fauna and flora (not just dinosaurs) worldwide but rather that as
>sea levels fell and several land bridges appeared where there were none
>earlier, diseases to which native populations had built up millions of
>years' worth of immunity would be suddenly released on populations not
>immune to them as various populations intermingled across bridges.

  Why would this wipe out pterosaurs and sea reptiles at the same time, and
not mammals and birds?

>One
>similar instance I can recall is the diseases Columbus et al. carried
>with them to the New World.

  This did not wipe out the majority of animals in the New World! It did
not even wipe out the majority of the one species that these diseases did
affect: Homo sapiens. Even the worst disease in history that I can think of
(the Black Plague of the middle ages) had no extinction effect.