Re: Is evolution more then mutation and selection?
- From: "Entertained by my own EIMC" <write_eimc@xxxxxxxxxxxxxx>
- Date: Mon, 1 Jan 2007 17:46:29 -0500 (EST)
<drosen0000@xxxxxxxxx> wrote in message
news:en3l2h$2ij0$1@xxxxxxxxxxxxxxxxxxxxxx
g wrote:
Glad you asked my (a layman's) opinion.
Once again, I respond from a position of trying to avoid words that mean
different things to different users and hearers.
It does not make sense to me that evolution is influenced ONLY by a
steady
uni-directional process of genes providing advantages which, over a long
period of time, float -- as it were -- the "best" genes to the top.
Let me list some reasons why:
1. First of all, what are "best" genes are not a constant.
This is why there is more than one species (also class,
phylum, kingdom) has evovled. This is also why some features often are
modified to have different functions in different species, or even
different developmental stages in the same species.
There has been no statement by any mainstream scientist,
including Darwin, that the "best genes are constant." Darwin explicitly
explains how variations in individuals have different fitness values in
different environments. I recommend rereading Darwin, as well as more
modern books on evolution (e.g., Dawkins, Gould). The shifts in fitness
value are an important part of evolutionary theory.
The standard theory seems to be that mutation is random with
respect to the fitness value of the corresponding variation. However,
there may be some functional direction in some mutations that many
mainstream scientists have ignored. After rereading Darwin (Dawkins,
Gould, etc.) I recommend the following book,
"Evolution in Four Dimensions," by Eva Jablonka and Marion J. Lamb (MIT
Press, 2006),
which explicitly describes mechanisms by which a sort of "fitness
direction" can be imposed on some mutations.
With people capable of reasonably proposing such mechanisms we can be fairly
sure that Nature has not just proposed but produced and preserved them.
Apropos which, another one of these people was Richard de C Studdert.
Moreover, the process of natural selection does (or so it seems to me)
contain (as if within itself) a constant-like subprinciple.
More specifically, one that makes animal evolution on any planet (or the
phylogeny of any fauna) prone to produce AEVASIVEly functioning phenotypes
by the fact that individuals whose respective phenotypes expresses an
ambiadvantageous [thus fitness-conferring/increasing and evolution-advancing
(i.e. functional complexity increasing)] mutation tend, on the whole, to be
selected-in ahead of siblings and other closely related and competitors
whose respective phenotypes expresses a likewise viable but
non-ambiadvantageous mutation.
P
.
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