One of Stephen Jones' signature quotes:
"I, for one, in spite of all the benefits drawn from genetics and the
mathematical theory of selection, am still at a loss to understand why it is
of selective advantage for the eels of Comacchio to travel perilously to the
Sargasso sea, or why Ascaris has to migrate all around the host's body
instead of comfortably settling in the intestine where it belongs; or what
was the survival value of a multiple stomach for a cow when a horse, also
vegetarian and of comparable size, does very well with a simple stomach;
or why certain insects had to develop those admirable mimicries and
protective colorations when the common cabbage butterfly is far more
abundant with its conspicuous white wings. One cannot reject these and
innumerable similar questions as incompetent; if the selectionist explanation
works well in some cases, a selectionist explanation cannot be refused in
others." (von Bertalanffy L., "Chance or Law," in Koestler A. & Smythies
J.R., ed., "Beyond Reductionism: New Perspectives in the Life Sciences,"
[1969], Hutchinson: London, 1972, reprint, p.65)
Chris
This is easy. Selection only works on variations. If different but still
advantageous variations occur in different animals, they will each be
selected for. Also, the environments and diets and other aspects of cows
and horses, have been different. The mere fact that they are both vegetarian
is only *one* fact to be taken into account. If one lives mainly on dry grass
and the other on green alfalfa, they will have different digestive needs,
despite the rather abstract fact that both dry grass and green alfalfa are
vegetarian foods. *Exactly* why one went one way and the other another
would have to be determined by a detailed examination of each case, but
the point I'm making is simply that they *are* different cases, and von
Bertalanffy treats them as if they should be the same because there is some
slight similarity between them. If we take this route, we could say,
Why are any species even slightly different from any
other species? After all, all species we know of live on
the exact same planet, and they all ingest nutrients.
One cannot reject these and innumerable similar
questions as incompetent; if the selectionist
explanation works well in some cases, a selectionist
explanation cannot be refused in others.
Frankly, I would not have expected von Bertalanffy, author of a classic book
on general systems theory, to make such a novice's blunder. But Jones
caught him, fair and square.
I would add that selectionism only explains what we see out of
the totality of variations that would have occurred had there not
*been* any selection. This is such a small portion of that totality,
that only a special calculation could get to within a few orders of
magnitude of the correct value, even if we knew early conditions
of the first form(s) of life. Selection does not explain the origination
of any trait, but rather the fact that that trait (or a precursor to it)
is still around for us to explain.
This is not a causal explanation of why the trait exists but rather
why it was *allowed* to come into existence and stay in
existence. Other, conflicting traits and other variations of the trait
that may have occurred were selected away, leaving only the one,
of those available, that "worked" the best.
But, which ones were available and at which times and places, is
a matter of chance. *Perhaps* the horse would be better off
*now* to have taken the cow's route, but if the correct variations
did not happen to occur, or did not occur at the right time(s) and
places(s), then the horse has to make do with whatever variations
on its existing digestive system actually *do* occur. Perhaps an
increase in stomach acid, or some new enzymes, or whatever. The
point is that not everything that might be good for a species may
happen to begin to occur when it's needed. Perhaps the cow's
stomach system is the result of a fairly major mutation that
happened to be of some value, and which evolved over time (via
other, smaller, variations) to the system cows use today (anyone
here know about the evolutionary history of the bovine digestive
system?).
Variation is the real "driving force" in evolution, because, without
it, there is nothing to select. Variation does not need selection, but
selection *does* need variation. Selection is like irregularities in
land guiding the flow of water, and the variations are like the
water itself, water that, on perfectly flat land, would simply spread
out in all directions evenly (see remarks on similes below).
I'm sad to say that naive or conceptually incautious evolutionists
have themselves been largely to blame for this fundamental
misconception of the nature of naturalistic evolution. Even my
own simile, above, is misleading, because it suggests that the
variations are guided along channels by some sort of barriers
corresponding to the banks of streams and rivers. This is not how
process works, so let's try another metaphor. Imagine that each
organism's genome has but two genes, and that these genes can be
gradated so that they can be indicated on an X_Y grid by two
numbers. Imagine that the offspring of each genome either occur
exactly where the parent genome occurs, or only a small distance
away, because the two genes can only vary a small amount for
each generation. Then, imagine also that there are certain parts of
the grid where the organisms that have these genomes are not
allowed to exist. If their x and y values land them in one of these
areas, there is a small but bright flash of blue light and a Zzzzt!
sound, and it disappears from the grid. This zapping effect is
selection at work. But, whether a particular genome's offspring
ends up in these forbidden areas or not depends on the variations
that occur, and how close to one of the boundaries the parent(s)
are.
To make the image simple at first, just imagine that everything to
the right of 10 on the X axis is "forbidden" territory. Then, if an
organism's genome has an x_value of 5, and variations only occur
in increments/decrements of 1, its offspring will be okay. But, if
the parent genome(s) are at 10 already, then it is possible that
some of their offspring will be at 11. Zap!
Notice that, in this way of looking at it, selection has nothing to
do, directly, with variation. It limits what variations may occur
only by limiting the locations of *existing* genomes on the grid.
Thus, there won't very likely be any genomes that appear with an
x_value of 30, because that's way too far from the *existing*
genomes' range of variation. Thus, current variation is limited by
*past* selection, but not by current selection. The *next*
generation's variations will be limited by what happens to *this*
generation's genomes.
But, variation itself is not under any direct influence from
selection, which occurs after the fact (except when/if it occurs
*during* the DNA_replication process when a variation already
produced somehow might corrupt the rest of the reproduction
process and "kill" the offspring genome even before it was
completed).
Naturalistic (i.e., Darwinian, loosely) evolutionists need to get
away from "explaining" things in terms of selection, even though
there is a certain "intuitive" tug to explain things that way.
Selection *does*, given suitable variations, explain why full_
fledged, fully developed traits of a certain sort are present:
Alternative, less_developed ones are constantly being selected out
during evolution to fit a niche. But, at each step of the way, it is
the variation process that provides the raw material to select on,
and if it does not happen to produce one set of variations that will
be allowed to continue, the result will be that *other* variations
will be allowed to continue, thus producing a different organism,
or the organism will go extinct or move to another suitable niche,
if the local selection "pressure" is too great.
Again, *variation* drives evolution. Selection *limits* evolution
so that it can only occur along certain fitness pathways.
Of course, things are complicated in the real world by the fact that
the "forbidden" zones are constantly changing, but the principle
still applies. Variations come spewing out and local requirements
for survival and reproduction "zap" the one's that land in the
"wrong" places on the "grid" (environment, internal viability,
reproductive capability, etc.).
Because these requirements are based on physics, chemistry,
metabolic requirements, local environmental factors, and so on,
and because these are lawful factors, they provide the substitute
for the intelligence lacking in the variation process. In effect, the
causal orderliness of the requirements for survival are
"intelligence," because they select according to consistent
"standards," standards that allow (some) orderly variations to
survive but none that are too disorderly to function or to maintain
themselves or to reproduce. In effect, the organisms we actually
see *are* designed (in a metaphorical sense) by the systematic
nature of the selection process. The "system" is not intelligent, but
it is causally ordered, and it does systematically cull out
disorderly genomes (often even before they develop a full
organism to carry them around) and many that are orderly but not
fit for the environment that they happen to be in. The result is that
organisms *must* have a certain kind of orderliness in order to survive at
all.
Scientifically naive people interpret that orderliness as intelligent
design because they don't see it in the context of the vast universe of
*other* variations that would have occurred if all variations survived and
were reproduced, nearly *all* of which would be genomes that could not even
generate a phenotype, let alone reproduce on their own. Perhaps one
trillionth of one trillionth of one trillionth of all variations would have
recognizable order, or allow for phenotypes. Maybe more, maybe less. I
don't really know, and I'm not about to undertake the years of study and
calculation that would be required to develop a sound calculation to
determine this. The point is that we only see orderly organisms because
only sufficiently orderly organisms have ever been allowed to reproduce to
provide a basis for further variations, only a tiny percentage of which
will be both orderly *and* improvements. Order and lack of improvement
would be more common, but, by far the vast majority would be disorderly and
harmful. Even neutral variations would lead to disorder in future
generations for the most part.
I'm using the word "order" rather loosely here, because there is ultimately
no such thing as true disorder. But there can be disorder relative to a
perspective on order, such as that that we humans tend to develop. And
there can be basic biological functional order that allows for the use of
energy, etc., even if the local environment does not happen to "reward" it
with the option of surviving and reproducing. "Disorder," from this
perspective, would be genomes or phenotypes that could not even live as
DNA-based organisms, or that could not live in the kinds of environments we
consider to be environments for living organisms on Earth. If an organism
is born with its eyes lodged in its digestive tract, we would consider this
to be disorderly by an Earth-bound biological perspective. An organism that
can't see and that can't eat or poop because of where its eyes are will not
live long.
The order we see in living organisms is due to their *simplicity* in
certain respects. They have distinguishable features, in other words,
features that we can see again and again, that can be studied and named. A
really severely disorderly organism would be a contradiction in terms,
because it would not be an organism at all. It would not have a digestive
system, it would not have metabolism, it would not have *any* of the
distinctive features of living things. A severely disorderly "tree" would
not have leaves, because the genes that would normally lead to the
development of leaves would be too broken up (too *disordered*) to function
as genes at all. It would have *no* tree features except for being made out
of matter, and even bare matter forces *some* order (each element has its
own structure, it interacts with other elements in certain fixed ways and
not in others, etc.).
There is ultimately, as I said, no getting away from order. But *life* as
such requires a certain orderliness as well, above and beyond that of mere
matter. Survival and reproduction in strenuous environments require yet
another "layer" of order of a certain type, to the exclusion of order of
different types. It is unfortunate that the naive cannot see the difference
between evolved order and genuinely intelligent design, but the differences
permeate life at every level, in residues of evolutionary history, in the
cumbersome excess complexity of cells, in the migration routes of organisms
that have extended their migration distances as continents drifted apart
(and now the distances are too great for a small adjustment to get them out
of it), and in the incredibly hodge-podgy nature of all large genomes (and
probably all small ones as well). None of these are conclusive against
design, but they *do* count against it, and they *do* count *for*
naturalistic, opportunistic, catch-as-catch-can evolution. We can predict,
on the basis of evolutionary theory that organisms that have evolved
through a long period of time through a wide range of environments and
survival requirements will have these "design" flaws. We cannot predict, on
the basis of the design premise (especially the *intelligent* design
premise) that these things would be found. In fact, if we did not know
better from empirical observation, and if we thought life was designed,
we'd guess that life would be much different from what it turns out to be,
because we'd guess that the designers would be intelligent enough, good
enough biological engineers, not to design a kludge like the human wrist or
the nerve pathways from the retinal cells in the human eye (the nerves go
*in front* of the light-sensitive rods and cones, thus blocking some of the
light). Things like the wrist *do* have evolutionary explanations, but no
design explanations, unless you count "Well, that's just the way the
designers chose to do it; who are we to question why the designers did
things the way they did?" This last, of course, is not an explanation *at
all*. It's the *evasion* of explanation. It's the assertion that what we
*do* know (that other organisms have properly-built eyes, for example)
should be *set aside* in deference to the mindless "Well, that's just the
way they did it" excuse. It is a demand on the part of ID theorists that we
ignore the *facts* of biological reality in favor of a belief in designers
whose minds are not known and who, judging from their work, are *idiots*.
Naturalistic evolution gives us a means of *understanding* why these crazy
facts *are* facts, because it gives us a means of showing how they arose
out of the accidents of history. These and many other facts make *sense*
naturalistically, but they *don't* make sense in *intelligent* design
terms. That's why ID theorists do *not* have an ID *explanation* for these
facts. That's why they are forced to hem and haw and claim, totally without
evidence, that their designer must have reasons of which we do not know.
They are, in effect, using the *failure* of their theory to "justify" a
bizarre *extension* of it. Now the designers are intelligent, but *we* have
no means of understanding their intelligence. On what grounds then, can
they be said to *be* intelligent?
In short, ID theory demands that we are to subvert our ability to
understand physical reality and even to think logically in favor of a
nearly mindless acceptance of a belief in a gang of unknown idiots.
This epistemological subservience to blind faith is the real horror. "Junk
your knowledge of physics, chemistry, geology, and genetics! Throw out your
knowledge of the history of life on Earth! Ignore the many facts of life
that make sense in naturalistic terms but yield nothing but excuses and
emptiness in intelligent design terms. Don't think, *believe!* Don't
question the human wrist, take it on faith that the designers knew what
they were doing; it doesn't work well, but who are *we* to question the
wisdom of the great and wonderful designers?" Etc., etc., etc.
(Sorry. Sometimes I get carried away by the endlessness of the evasions and
nonsense and anti-science coming from the ID camp.)
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