Re: Is evolution more then mutation and selection?

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. For example,
when Earth had little oxygen in its atmosphere, some of the best
morphological "survival" traits some of us take for granted as being
desirable today could have meant certain and instant death;

2. What is a desirable gene-induced trait even here and now, is a dependent
variable. For example, what serves to keep a polar bear from freezing in
sub-zero weather would cause death in a part of the globe which is hot. In
fact, even the slightly warmer temperatures nearer to the North Pole today
are causing polar bears stress. Not only is
the disappearance of much of the ice up there making it more difficult for
polar bears to move about to access certain food sources they need but,
also, polar bears are being observed to be heat stressed during warmer
weather.
Hence we cannot say that the genes which provide advantage in one
geographical area provide advantage in all geographical areas. And there
are other kinds of geographical differences which can vary the invironmental
"demands" upon a gene pool than just temperature.

3. Not only to "invironmental demands" vary from place to place at a single
moment in Earth time; they also vary in a single Earth locale over time.
Not only are there seasonal cycles. There also are Earthwide cycles
relating to longer term changes in the Earth's path around the sun and in
Earth's tilt in respect to its magnetic polarity and the angle of the sun's
rays on various parts of Earth.

4. For a species to change, it must have a sufficient number of genes in
its gene pool to enable SOME survivors to remain after a change. If NONE of
a species has any genetic capacity to survive, and ALL members succumb to a
change, then there are no survivors around to carry on by reproducing.
Mutations are a means whereby some atypical genes can be introduced into a
species and, sometimes, can make the difference between total anhililation
of a species and reduction down to a core of individuals having a gene that
can survive a particular kind of change, and then multiply and repopulate.

5. Change can be slow or fast. A fast geographical change, such as a
volcanic eruption so large that it blankets a large portion of the earth
with debris that blocks the sun's rays, can render "invironmental demands"
which many species may have zero survivors. Large estraterrestrial bodies
striking Earth can cause sudden and drastic "invironmental demands" which
may decimate some populations directly by physical trauma, or may reduce
food supplies to a minimum, or cause some species to be wiped out (whether
quickly or slowly) entirely.

6. A particular disease, resulting from a mutation of a particular pathogen
can be catastrophic to one species or many. In this case, populations of
isolated areas, such as islands, which would have no survivors if that
disease were to get among them, may survive NOT because they had any genes
AT THAT TIME which would provide any of their members ability to survive.
The *survivors* in such a case are NOT survivors on grounds of genetic
advantage. In such cases survival is based upon a totally different basis
than survival of the "fittest." Just as we would be foolish to try to
figure out what is "fittest" about lottery winners, we must face the fact
that some
survival is what could be called survival by means of factors having little
or nothing to do with genes.

7. What is advantageous (among things that ARE gene based) is a variable
among species and among some sub-groups within a species. For example, what
is good for a fish, or neither good nor bad for a fish, but neutral in its
impact on a certain species of fish, may be very bad for a particular
mammal. For example, if an island sinks beneath the sea, some mammal
species on that island may be unable to swim to a habitat they could survive
in. And some fish species might also be impacted by the sinking of the
island, because they may have developed in a way that is dependent upon
something that lives on the island, which provides a certain food source
they will no longer have after the island is awash.

8. Because of some of these variables, it does NOT seem to me (a layman) to
make sense that we should define
the current nature (at this place we call here, TODAY, and at this time we
call now, TODAY) as being a product of ONLY survival of the "fittest,"
UNLESS we define fittest simply to mean those characteristics which AT ONE
PLACE, AT ONE POINT IN TIME enabled or simply ALLOWED certain genotypes
and phenotypes (and morphologies) to get to be around long enough to
reproduce... thus continuing the chain of "life."

9. To this layman it seems that too many individuals (some of them even
claiming to be scholars) are prone to
attribute "survival" to one or two, or a handful of, characteristics which
they assume to be established on Earth now, on grounds that they had some
quality a million years ago which was advantageous then and therefore is
advantageous now. Nothing in what really goes on supports such a simplistic
notion. And, just ONE of the many problems with such a notion is that what
was advantageous a million years ago would necessarily be advantageous now,
or a million years later than what we now call now.

10. This is a very important point, too, I think: No species can get to
another place in an evolutionary chain of events without going from where it
is morphologically at any given time. For example, it seems perfectly
reasonable to me to envision a link in a continuous chain of reproductions
in which a fish species we now find COULD have gone from where it was then
to being stressed in such a way that members of that species LINK could have
made their way, say, up onto a beach to get food, while their cousins
perished for lack of food. But the CURRENT SPECIES LINK having quite
successfully adapted to some OTHER variables of invironmental demands, could
very well have move away in morphology from where THAT FORMER "species
link in the chain of reproductions was, and would perish now if it had to.

11. If we humans wish to assign certain characteristics to nature as suit
our fancies, our egos, or our evident desire to put things as simply as they
can be put... then the very least we can do -- if we EVER would hope to "get
it right" is to list all the exceptions to some of our most simplistic
notions that simply are neither general in all places and times at a single
freeze frame moment in the continuous FLOW of survival, nor consistent from
place to place, nor from time to time, nor from species to species.

I am not trying to foment any original theory here. All I am trying to do
is point out some rather simple and extant issues that make sense to me, and
which it seems to me some other lay people, and maybe even some people who
admire their own scholarship seem to me to overlook, as well. This is not
an indictment on my part. It is merely an attempt to make sense of some
things that others say (or preach) which do not seem to this layman to fit
some of
the natural realities.

And often, it appears to this layman, some of the problem lies in reliance
of some thinkers on words that SUGGEST things that are not in accordance
with what is going on in nature that all of us are aware of, if we think
about it and quit trying to impress one another with nomenclature that (even
if it only plants false suggestions in our subconscious minds) lead us to
think along certain paths that skew away from what actually goes on in
nature.

g


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