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Archiver > GENEALOGY-DNA > 2002-09 > 1031194767


From: "Bonner, Gregg" <>
Subject: RE: [DNA] Toba bottleneck
Date: Wed, 4 Sep 2002 22:59:28 -0400


I think "survival of the fittest" nowadays is just a catch phrase which is
used by American High School science teachers who otherwise know nothing
about the subject matter. Generally, 'survival' even in the broader sense
(fit or not) has little to do with evolution. For example, let's take "A"
and "B", where "A" is super-fit, and can expect to live 1000 years. On the
other hand, a single point mutation leads to "B", which is terribly weak,
and on the border of death always, and can expect to live only 100 years.
Yet this mutation leads also to a condition whereby "B" (and his mate) can
have 5 children, whereas "A" (and his mate) can only have 2. I will not
bother with the specific math except to say that "B" will outcompete "A" to
oblivion (virtual comparative extinction), in spite of being unfit, and not
doing a good job of survival. So fitness only comes into play inasmuch as
you are not very fit if you are dead, and survival only comes into play
inasmuch as it is difficult to have children when you are dead. This much
should be obvious, for otherwise death would not have been SELECTED FOR by
mother nature.

Consider the American human population as a whole. Imagine the
sub-population that is routinely having 5 children. Now imagine the
sub-population that is having 2 children. Is the group having more children
a more fit group? Is it the group with greater survival? Nevertheless,
2->4->8->16, but 5->25->125->625. So it would seem that America could be
inherited precisely by the MOST unfit.

So to address the bottleneck issue, my understanding is that if a global
thermonuclear war were to ensue such that everyone fired all they had to
kill as many people as possible, still nobody would have enough to launch
one at Papua New Guinea, or better, Antarctica. So those would survive, yet
not by their fitness.

And finally, about antibiotics, I must agree with the original sentiment.
What is the alternative - not prescribe them? What is the point of having
them if you can not use them? To say that they lead to resistant bacteria is
to claim that antibiotics are mutagenic, otherwise the mutation is naturally
occurring, and not the result of the drug. I think the original argument was
that to knock down some bacteria was harmful because THEY held other, more
harmful bacteria in check. Now this sentiment has transmogrified into
nonsense. I say use them for all they are worth, and when they are no longer
worth anything, find others. The alternative to this is to not use them, and
what good would this do? 'I am sorry, Mrs. Jenkins, we can't cure your
daughter's meningitis because we fear she will begin to harbor
super-meningitis.'

Cheers,

Gregg









-----Original Message-----
From: [mailto:]
Sent: Wednesday, September 04, 2002 9:16 PM
To:
Subject: Re: [DNA] Toba bottleneck


In a message dated 9/4/02 3:18:12 PM Pacific Daylight Time,
writes:

> . 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."

Hi John,

I don't think there is anything special about the survivors. No human can be

conditioned to survive a volcano. There was something special about the
geography. When Mt. Saint Helens blew its top the weakness on the volcano
and
the air currents dictated where the ash fell. With Toba did the same thing
in
a mega way the same conditions dictated who lived and who died. About 10
million years ago a mega volcano in the area that is now Yellowstone Park
dumped up to 6 feet of ash in Eastern Nebraska. It killed animals in
between,
not because they had a genetic flaw, defect, or weakness, but simply because

they were in the wrong place.

I really don't know if Toba was the cause of death for humans. I understand
evolution and I know that many factors, including mass extinction,
contribute
to modern human evolution.

Grant Johnston, Chico, CA


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