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Re: Extinction scenarios



TomHopp@aol.com wrote:

<lots o' interesting stuff snipped>

>     Secondly, any organism that has perfected its ability to kill its host, by
> killing one hundred percent of its victims, does not prevail.  Rather, it
> becomes extinct itself, due to the inability to be spread from one host to the
> next (remember, the first host is dead).  There is, therefore, a selective
> pressure for inefficient killers to remain inefficient. Witness influenza and
> the common cold, which are still very much with us, while bubonic plague, a
> greater killer, is nearly extinct.

A small question: what about something like rabies?  I don't think I've
ever heard of a natural immunity to rabies -- if a species is vulnerable
to it, which most mammals are, then any individual of that species can
get it.  And rabies has the nasty habit of making its hosts very
contagious before it kills them.

Or what about something like Brucellosis?  That doesn't harm the host
directly at all, it just vastly reduces reproductive success.

-- Jon W.