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Re: K-T Theories
> I went to Dr. Bakker's lecture last Friday here in Portland, Or. He promotes
> the disease theory of the K-T boundary.
There is a letter to the editor in Nature (7 April, 1994) by Victor
Buckwold concerning viral-induced extinctions. He is
specificly discussing phytoplankton-infecting viruses, but I
think his point is relevant to dinosaurs as well:
"Viruses are obligate parasites, and their survival depends on the
survival of the host. If a virulent virus reduced the population of its
host, the virus population would similarly be reduced until a balance
(steady state) was achieved...A virulent virus can only emiminate a host
population if the virus can also live in another host which it does not
Eventually, the virus has reduced the population density of the
host organism to levels where the hosts do not come into contact
frequently, thus preventing continued rampant spread of the virus.
Precluding a second host organism which is not killed by the virus
(and which would have to have a similar geographical range as the
dinosaurs) it seems unlikely that a virus alone could cause actual
extinction of a species, much less a genera, and much much less the
And anyway, dinos weren't the only organisms that became extinct at
the K/T. The K/T extinctions seem too complex to be attributable to a virus.