A better formulation of the question is: Does selection *occur*? Selection
is not a "thing," like a rock. It's a type of event or a set of events, any
one of which may count as selection.
*Does* selection occur? Yes, any time an organism is killed before it
either reproduces or contributes all it might otherwise to reproduction.
Any time the initial genotype is corrupted in such a way that the organism
never really develops. Any time a variation occurs during DNA replication
such that the rest of the DNA replication process is corrupted so that even
the first cells of the new organism are nonviable. Any time a flood or
volcano wipes out a species (in fact, any time a species goes extinct at
all). Any time the organism is healthy but is genetically basically viable
but is in an environment that provides insufficient resources for it to
reproduce. Any time an organism that depends on sexual recombination for
reproduction is unable to find a mate.
Even mathematically *random* selection is still selection, so that, even if
a certain percentage of a population of a species is killed off in such a
way that the distribution of "natural selection" and "designed selection"
together is effectively mathematically random, it is still selection. And,
in this case, there will tend to be a genetic distribution that reflects
this randomness.
Genetic drift is *also* selection. It increases the prevalence of some
genes relative to others, thus selecting against the others. If the drift
continues long enough in one direction, some genes may be lost altogether.
Genetic drift selects for certain genes at the expense of others. The
genotypes that *had* the genes do not get fully reproduced; they are
progressively selected out. For whatever reason, some of their genetic
material is not "fit" enough to ensure that it survives the replication
process itself.
If selection did *not* occur, if *every* genotype that ever existed was
always somehow able to reproduce (at a rate equal, say, to that of its
closest naturally viable ancestor), the entire galaxy would now *be* a mass
of strands of nonviable DNA and the weirdest organisms you can imagine
(assuming it could be kept from collapsing into a huge black hole).
Exponential population growth over 3.8 billion years would require some
God-like being to keep providing more matter, just for the DNA strands.
Selection occurs, all the time, for almost every species, even humans. For
example, my own genes will almost certainly be selected out, because I do
not plan ever to have children. Is this "natural" selection? It doesn't
matter; it's still selection, and much the same happens to non-human
organisms fairly frequently, but without planning, and as "naturally" as we
can imagine.
Why would anyone, such as Stephen Jones, declare absolutely that selection
doesn't occur?
Why, having thought of such a notion, would a person not pause for a moment
and check out the idea in the light of potential counter-examples?
Why is this kind of blatant lack of critical thought applied to one's own
views so *hugely* prevalent in the ID-theory crowd? Why don't Jones,
Johnson, Behe, Dembski, Thaxton, Schutzenberger, Bertvan, and the rest ever
notice just how bad their facts and reasoning are?
Is there anything that can be done for these people? Probably not; their
meme-systems are almost perfect closed at the core, so that information
only gets in at a remote distance from the core, and is processed solely
(or nearly so) to find ways to support the central system of memes. Faith
is supported by faith in faith, faith in faith is supported by *severely*
selective processing of incoming information. Logic is used almost strictly
as an instrument to construct arguments to support one's views or attack
opposing ones, or for trivial, mundane purposes, not to examine the core
ideas themselves. The egotism of faith is supported by the faith in faith
(if one's *own* faith can't be trusted, maybe faith *isn't* such a hot
thing, so, naturally, one's faith must be trusted if faith is already
accepted as a valid "method" (it's really a non-method)). The egotism
itself supports the belief in one's own infallibility ("Look at all the
truths I established by faith"), and this supports the belief that one need
not critically examine one's own ideas or arguments, because one believes
one is *so* automatically reliable that such examination of one's own ideas
would just be a waste of time (and the idea that it would be a waste of
time is itself attractive precisely because it helps protect the egotism,
etc.). Etc., etc., etc.
Thus, the idea that "selection" is a metaphor arrives at the door of
Stephen's mind, fresh from some book. He concludes that this means that
selection does not exist; it's only a metaphor (he does not ask *what* it's
a metaphor for). Having concluded this, and being egotistically "sure" that
his own instant conclusions are true, and having a good "feeling" about it,
he is ready to start declaring that selection does not exist. It is not
necessary to consider whether it is compatible with empirical facts of
which he knows, such as the extinctions of species, the fact that some
organisms obviously cannot live in certain environments, the fact that, in
many cases, the slow prey will get caught and "selected" out much more
often than otherwise similar but much faster prey, etc. This would be too
empirical for him; playing a little game with a few beads is about as
empirical as he will get.
Why harp on the deficiencies of Stephen Jones' way of thinking? Because it
is a somewhat purified version of what *many* ID theorists (and people
generally, for that matter) do, and the mechanisms and results are worth
knowing about so they can be detected and avoided, especially in one's
*own* thinking.
However, to get back to the topic of evolution for a moment, Stephen has
touched on an interesting point. That is that, *if* selection did not
occur, or did not occur systematically enough to account for the general
distribution of life as we see it (as opposed to a galaxy-full of DNA and
wacky organisms piled everywhere throughout all available space), *then*
the lack of such post-selection *combined* with the rather narrow
distribution of life that we have on Earth, would suggest that something
was doing some *pre-*selecting. This something, if it existed, could be a
designer, though, even then, we'd have to eliminate such things as strong
predispositions for certain kinds of chemical reactions to occur rather
than other ones under various conditions, etc.
Thus, *if* there were no selection, it would serve as one key fact in an
argument for design.
Perhaps that's Stephen's real reasoning. I don't know; perhaps he'll
explain his position on this more fully. But, consider that, *if* a person
already firmly believed in design, then, obviously, one might want to
eliminate natural selection (or natural exclusion, to be more verbally
precise), and attribute the existing distribution of life to the designer's
*pre-*selecting of genetic material. This is, in this case, backwards
reasoning, because the very point at issue is whether there is a designer,
so it does no good to *presume* that natural selection does not occur. This
is something that one must prove, and not with such a pitiful method as
pointing out that the terminology is metaphorical, and that there is
nothing sitting around consciously choosing which organisms will die and
which won't, etc. We already know that; that's not what the idea of natural
selection is about. I *really* wish it had been called something like
"natural exclusion," but it wasn't.
Also, virtually naturalistic evolutionists are Platonistic/Rationalistic
enough to reify such a concept anyway; that's something that is *much* more
prevalent among theists (particularly Christian theists). We know that it's
a general term for the occurrence of a genome or gene or organism being
excluded from further reproduction (or from reproducing as much as it might
have otherwise). We don't think of it as some sort of "thing," like a rock,
or even a *process* (though that is much closer). It's *any* event that, in
context, prevents something from being reproduced.
Thus, it even includes the exclusion of a gene via genetic drift; the gene
is not "fit" enough to ensure that the reproductive process transfers it on
to the new genotypes reliably. It may be a perfectly good gene, but in a
bad location (in the genome), or it may have some chemical characteristic
that leaves it unreproduced more often than alternative alleles, etc.
I hope this answers any burning questions people may have had left after my
first post on this topic. And, I hope that it will encourage people to be a
little less hasty in accepting ideas merely because there is something
intuitive about them, or because the terminology used to identify a class
of facts is metaphorical in some way.
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