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Re: Scientists Claim to Find Mechanism of Natural Selection



        Hmmm... natural selection... dinosaurs... relevant? I suppose, I
just hope I'm not encouraging a raging non-dino debate here...

Greg Claytor wrote:
>Reprinted from www.foxnews.com
        Oh, dear god, we have turned to the masters of sensationalist
television for science news... I wonder how many of the problems in the
quoted article are due to its being covered by "network" news. And the Jerry
Springer of network news at that! "When scientists attack?"

>"Evolution used to be about arguments. Whoever had the best argument
>won, because there was no way to study it," said David Gardiner
        Is it just me, or is this statement wrong?

>. By guiding the proteins,
>Hsp90 ensures their processes lead to normal development of their
>corresponding traits ? or their so-called expression ? in the body.
[...]
>When a body falls under stress, Hsp90 attends to the crisis and can
>start to neglect its normal role of ensuring the correct expression of
>new proteins.
[...]
>These deformities, Lindquist argues, are evidence of natural selection
>at work 
        [My short def:] Natural selection is the process (if it is indeed a
process and not a tautology) by which the genome of those individuals which
are better able to pass their genome into the next generation is found to be
more prevalent in the next generation, with the result that those phenotypic
characters which tend to contribute to the overall reproductive success
(including survival) of the individual (or its genome...) tend to become
more prevalent in the population.
        With that in mind, what does this new research have to do with any
of this. I see no "mechanism" for natural selection, nor do I see a need for
one.
        More importantly, how is the stress-induced misexpression of the
genotype "natural selection" in any sense of the phrase? Unless we are going
back to Lamarckism, whereby the phentotype (not the genotype) is inherited,
the abberations of which the authors speak WILL NOT be inherited by the
animal's offspring (unless science has completely changed since I took Bio 202).
        How can "these deformities" possibly be "evidence of natural
selection at work?" No selection is occurring. The abberant expression of
the genetic code seen in this experiment is a fantastic demonstration that
phenotypic variation can occur without changing the genetic code, but I
don't see how it possible shows that natural selection (as outlined above)
occurs.

>the problem does not appear to lie within the frogs?
>genetic codes, but in agents responsible for gene expression, [...]
>"What we?re seeing in the frogs is a developmental disruption,"
        Exactly!

>This variation surfaces when the body is under stress and gives rise to
>quirks of nature ? an elongated nose or a sixth toe or a third eye ?
>which either disappear from the species or persist if they prove
>favorable to survival.
        And HOW are they to persist if the genome has not been changed?

>If reducing the role of Hsp90 leads to the unmasking of
>deformities, then, she infers, a wide array of variation must already
>exist within each individual?s genetic code.
        Maybe Mickey, who has been so helpful in explaining molecular
biology to the list in the past, can touch on this. It sounds like these
folks have inadvertantly stumbled on/over/around the last couple decades of
biology.

>Could environmental hazards unleash a string of deformities
>among humans, perhaps even leading to a different form of ourselves?
        Dear lord, are we regressing all the way back to the '50s? Ooooh,
dear me, let's hope we all don't turn into Morlocks... or dinosaurs (there,
see, it all relates to dinosaurs... :) .

        Wagner

--------------------------------------------------------------------------------
     Jonathan R. Wagner, Dept. of Geosciences, TTU, Lubbock, TX 79409-1053
 "Only those whose life is short can truly believe that love is forever"-Lorien