On Sun, 9 Apr 2000, alexs wrote:

> An article in Medical Hypotheses some years ago
> proposed somthing along these lines, namely that
> the huge free radical buildup resulting from a
> near-scurvy existence encouraged large numbers
> of mutations. The rapid DNA alterations in primates
> led to high adaptability and "forking" of the
> genetic lines. Possibly the very existence
> of H. sapiens resulted from the "fortuitous" disabling
> of the GLO gene. Of course, Man's chronic misery
> over the eons due to this loss was the price to
> be paid.

It's an interesting article, from which I quote:

        About 165 million years ago, when Nature had the
        evolution of the more active and stressful mammals in
        view, an important morphological and physiological
        decision had to be made. The kidneys, while adequate as
        the site of ascorbic acid synthesis for the rather
        sluggish cold-blooded vertebrates, were inadequate for
        the increased ascorbic acid needs of the more highly
        stressed mammals. The successful solution of this problem
        was the transfer of the enzymes for the production of
        ascorbic acid from the relatively small
        biochemically-crowded kidney to the more spacious liver,
        which is the largest organ of the body. All present day
        mammals capable of synthesizing ascorbic acid are liver
        producers because any ancient form which did not make
        this transfer was so biochemically handicapped that they
        were eliminated by the forces of Evolution.

What do you suppose Stone means when he says that "Nature had the
evolution of the more active and stressful mammals in view"?
Also, in the same article, Stone has a chart showing that the
transition from kidney synthesis to liver synthesis occurred in
"more recent orders" of birds.  What does this have to do with
mammals?  Does he have evidence of early mammals that were kidney
synthesizers?  If so, he doesn't present it.

Finally, we have to consider the number of mutations that would
be needed to "transfer" the ascorbate synthesizing function from
kidney to liver, and the exquisite timing needed.  We need
mutations to shut the kidney synthesis down.  Well, that's not so
bad since we know that a mutation that disables one of the four
enzymes will accomplish that.  But then we also need the
mutations to *make* these enzymes in the liver, and we need them
all to be in place before kidney synthesis is shut down.  That's
pretty amazing.

Todd Moody
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