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From: "john flinn" <>
Subject: Re: [DNA] Toba bottleneck
Date: Wed, 4 Sep 2002 14:38:12 -0700
References: <14f.13839a3a.2aa7b804@aol.com>


To Grabt and all concerned;
With all due respect, I wish to clarify a misunderstanding many people have,
including Dr. Ambrose, and which is propagated by your explanation below.
Global tragedies such as Toba's erupuption can wipe out 95%, or so, of the
population. So 5% survive and carry on. Who are the 5% that survived? The
strongest, most fit of the species survived. Lest we forget, remember "The
survival of the fittest" , the basic tenet of the process of evolution? The
five % that survived were already evolved and conditioned to survive, or
they wouldn't have done so. But they were such a minority of the previous
population that we are (were) virtually unaware of their existence. So, when
they are the only ones left, we erroneously say; "Toba caused the sudden
spurt of evolution." The only thing Toba did was to cull out the weak
specimens, like Laban in the Bible, culled out the undesireable sheep from
his flock, or as modern stock breeders do, paying premium prices and stud
fees to get the best offspring. They are not causing rapid evolution, just
selective breeding. That's what mother was doing with the fiv% survivors.
Many of our scientists quote "the overuse of antibiotics cause bacteria to
mutate and evolve". Rubbish! The few bacteria already immune to the
antibiotic survive and propagate, giving the illusion of mutation, since
their genes were already evolved, and made them capable of withstanding the
onslaught of the antibiotic. Of course their offsprings will inherit their
immunity, and also be immune to that particular antibiotic. Okay?
Thanks for your time,
John Flinn

----- Original Message -----
From: <>
To: <>
Sent: Wednesday, September 04, 2002 12:24 PM
Subject: [DNA] Toba bottleneck


> In a message dated 9/4/02 11:26:41 AM Pacific Daylight Time,
> writes:
>
> > I have never heard of this explanation for the bottleneck before, and I
> > consider it highly unlikely. Please cite a source for Toba wiping out
the
> > human race.
>
> I don't know how likely it is but the theory was published in the June
1998
> issue of the Journal of Human Evolution.
>
> Late Pleistocene human population bottlenecks, volcanic winter, and
> differentiation of modern humans
> Stanley H. Ambrose
> Journal of Human Evolution, Vol. 34, No. 6, Jun 1998, pp. 623-651 (doi:
> 10.1006/jhev.1998.0219)
>
> Past Effects of Volcanic Eruptions
> Toba Bottleneck
>
> Approximately 71,000 years ago a horrific volcanic winter was brought on
by
> the eruption of Mount Toba in Sumatra. This volcanic winter followed by
the
> coldest 1,000 years of the Last Ice Age caused massive death and famine to
> modern human and animal populations throughout the world. The results of
the
> super-eruption of Toba may have also been a "bottleneck" in the evolution
of
> modern humans. A "bottleneck" is an abrupt decrease in population,
followed
> by rapid "differentiation" - or genetic divergence - of the surviving
> populations. Anthropologist Stanley Ambrose of the University of Illinois
> proposes that a volcanic winter reduced human populations to "levels low
> enough for evolutionary changes, which occur much faster in small
> populations, to produce rapid population differentiation," Ambrose said.
If,
> as he believes,the eruption of Mount Toba in Sumatra caused the
bottleneck,
> "then modern human races may have diverged abruptly, only 70,000 years
ago,"
> Ambrose wrote in the June (1998) issue of the Journal of Human Evolution.
>
> Grant
>
> "The nice part about living in a small town is that when you don't know
what
> you're doing, someone else does." -- Unknown,
>
>
>
>
>
>
>
>
>
>
>
> ==============================
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go to:
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