Re: An introduction

In article <JbnRf.56362$Jd.7221@xxxxxxxxxxxxxxxxxxxxxxxxxx>,
John Harshman <jharshman.diespamdie@xxxxxxxxxxx> wrote:

forcythe@xxxxxxx wrote:

Scientifically why is evolutionary theory treated almost exclusively as
Darwinism or Neo-Darwinism and its unyielding focus on natural
selection and an oversimplified concept of mutation via genetic
mutation? Both sides of the debate are often guilty of this error, and
it makes the whole discussion pretty useless.

Agreed for the first part. But it only makes a part of the discussion
useless.

Clearly natural
selection is very important as the "bottom line" so to speak,
determining in the end the differential advancement of existing
variation, but it speaks little to the source of variation.

Of course. It speaks nothing to the source of variation, which is mutation.

Genetic mutation is the "raw source" of variation, but alone is not a
strong enough force to explain the variation required for the evolution
we observe. Means for that genetic variation to spread and affect the
variety of phenotypic variation it may cause within populations is
necessary, and itself is a stronger force of evolution than mutation.
Here I'm thinking primarily of drift (and to a lesser extent
migration), too often ignored and necessary for the model to stand.


Let's not
forget the other forces of evolution that are at play. Phenotypic
mutation is not due to genetic mutation alone.

Phenotypic mutation is not a technical term, to my knowledge. Phenotypic
differences may or may not be related to genetic differences. But those
that aren't related to genetic differences can only rarely have any
significance to evolution.

Perhaps I was speaking a bit too casually there. I was trying to
distinguish between the sort of mutation that Darwin was able to
observe, referring to it as phenotypic mutation, and the genetic
mutations that the Neo-Darwinian synthesis draws upon to account for
it.

Genetic material is obviously the medium for inheritance and selection,
but mutation is not the only way that significant phenotype-altering
changes occur within the genome.

I see that Dr. Wilkes has elaborated further on additional types of
interaction between phenotypic change and genetic change that goes
beyond my area of intimate familiarity. Part of why I'm here is to
dust off my evolutionary theory and avoid its atrophy into something "I
once kept up with."


There are much stronger
forces at work to change genomes than mutation.

If there are, I don't know about them, or any evidence for their
existence. Can you explain?


For example, the ability for drift along with your basic meiosis to
shift the frequency and combination of genes in a population has a much
stronger and swifter effect than the introduction of new genes through
genetic mutation alone. New genes via mutation are necessary, but not
sufficient.

Well, if this doesn't get my urge to post off my chest, I hope to take
part in the conversations to come. I look forward to the assaults from
all sides that typify this debate.

You will not be disappointed, though you might not get any replies from
creationists.

That has been another beef as I've lurked and watched the debate, but
not one that I figured I could affect in any significant way :(

~N

.

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