This is yet another little essay. Although ID theory is not testable in the
ordinary way because it makes no predictions of empirical (i.e.,
real-world) facts that should be the case if it is true and not the case if
it is not, one of the primary claims of ID's *supporters* is that
macroevolution does not or cannot occur. *This* claim *does* have empirical
implications. No matter how hard we search, we should not observe
macroevolution or find strong indirect evidence supporting it. Further, the
claim that macroevolution *does* occur has its own implications,
implications that can be (and in many cases have been) tested. If
ID-supporter claims are true, the macroevolution idea should flunk
definitive tests. What I suggest below is that it passes such tests, and
that the no-macroevolution claim does not pass such tests.
Introduction
Although ID theory itself does not imply that macroevolution does not
occur, one of the claims used in support of ID theory (to keep it from
appearing too blatantly superfluous) is that macroevolution cannot occur.
In principle, it could just be claimed that it occurs or can occur *so*
rarely as to make *it* superfluous, but, in practice, ID folk seem to claim
that it does not occur at all, and that it doesn't because it can't. If it
were accepted that NET (naturalistic evolutionary theory) macroevolution
occurs as frequently as evolutionists are wont to claim, then, on obvious
grounds of parsimony, most of ID theory claims would be superfluous.
Thus, while the denial of macroevolution is not itself a part of ID theory,
ID supporters effectively have to make this claim to keep from seeming
sillier than they already appear (for the most part). Therefore, if a
nearly conclusive case is made for macroevolution, then, even though ID
theory is not really testable, ID theory will not have anything to
recommend it over NET. Obviously, if a designer is clearly not needed for
the phenomena to be explained by it, then it becomes merely an arbitrary
assertion.
The Denial of Macroevolution
The idea is that there is some "barrier" or "attraction" around existing
"median" species genomes such that any variation beyond a certain point is
impossible (or vanishingly unlikely).
But, immediately, there is a problem. Though evolution slows (on average)
as variations move from a well-adapted "median" genome, there seems to be
on *actual* limit to the number of microevolutionary steps that can occur
cumulatively to allow a population of one species to evolve into a new species.
Of course, the more serious problem is the fact that new species *have*
been observed to evolve from existing species. Jeffrey Jay Lowder, for
example, says,
Finally, Noebel claims that evolutionists simply assume that evolution is a
fact despite the lack of observational or fossil evidence for
macroevolution (pp. 269_270). Nothing could be further from the truth.
First, evolutionists do not "assume" evolution is a fact; they infer
evolution from the evidence! The evidence for evolution . . . comes from a
wide variety of disciplines, including biochemical and genetic studies,
comparative developmental biology, patterns of biogeography, comparative
morphology, anatomy, and the fossil record. Second, macroevolution has been
observed. Although on the evolutionary hypothesis we would expect observed
instances of macroevolution to be rare, nonetheless we have observed
instances of macroevolution in both plants and animals. The observed
instances of speciation include the macroevolution of two new species of
goatsbeard, a species of fireweed, a species of beetle, a species of worm,
the Faeroe Island house mouse, and five new species of cichlid fishes. And
third, the fossil record does contain transitional fossils. Some of the
most notable examples include "the transitions from reptile to mammal, from
land animal to early whale, and from early ape to
human." (http://www.infidels.org/library/modern/jeff_lowder/noebel.html)
Thus, not only does macroevolution, by any reasonable definition, occur, it
occurs often enough to be fairly readily observed by humans. The
counter-examples mentioned above and others indicate that the ID-dependence
on the claimed non-occurrence of macroevolution is shaky at best.
The solution? Expand the definition of "macroevolution" so that the span
between one species and any species that is a macroevlutionary "distance"
away from it cannot be bridged even by evolving through *multiple*
intermediate species.
The tactic here is to progressively keep asserting that macroevolution is
not observed by making the required observations progressively more difficult.
However, once it is proved that one species can evolve into another, there
cannot be any reasonable basis for claiming that *that* species cannot
evolve into yet *another* species, in much the same way as is suggested by
cladistics, genetics, fossils, animal and plant breeding, and so on. That
is, once the "boundary" between biologically "adjacent" species is crossed,
there is no stopping macroevolution. This boundary is more conceptual than
real, anyway; there are *no* fixed "types" of organisms that do not and
cannot change in time. There is no fixed genome that can never vary beyond
a certain amount. This is a kind of lame holdover from the Platonic theory
of forms, of fixed and perfect "ideas" that are reflected poorly and
imperfectly in the objects we observe perceptually.
At any given time, there are "types" of a sort, because selection weeds out
less-functional intermediates that would vie for the same ecological niche.
But, this is a localized and fluid phenomenon; the "types" *do* in fact
change over time; they are not rigidly fixed.
Further, even if it was in fact true that we did not observe speciation,
the existence of macroevolution, without positive evidence of the inability
of a species to evolve into another species, and *with* the various forms
of indirect evidence of speciation (such as the variety of
currently-existing species, fossils, and what is known of the molecular
process of DNA replication) would all support the proposition that
macroevolution does and has often occurred. Given this, the only way that
the no-macroevolution claim could be viably supported would be strong
*positive* evidence against macroevolution (i.e., *for* an extremely
limited range of cumulative microevolution).
Since: a) no evidence of such an uncrossable barrier has been found, and,
b) microevolutionary steps *are* empirically cumulative, the presumption
has to be that microevolution can occur sufficiently many times in a
cumulative fashion to allow the development of new species, and even new
species many times removed from the ancestor species (i.e., man from
primitive autocatalyzing sets of molecules).
Of course, this last is not a proof that macroevolution occurs. It is
purely an Occam's Razor argument for *presuming* (until and unless evidence
indicates otherwise) that macroevolution is merely multiple steps of
microevolution occurring cumulatively.
Information Theory
Each new genome, in general, contains new information relative to any other
genome. Even the *deletion* of information from an information-pattern can
produce new information, in terms of the meaning of the information. To see
this, delete the word "not" from the following sentence:
We find the defendant not guilty.
What this means, in genetic terms, is that even the deletion of information
may produce significant morphological and or physiological changes in the
resulting organism. In fact, at least in principle, deletion of genetic
material could produce a new species with blatantly different morphological
characteristics. If the information deleted caused *other* genetic
information to be ignored morphologically, then deleting that first piece
of information could even result in the presence of a new morphological
feature.
Thus, the claim of some that new information is not produced by genetic
variation is simply false. In the case of organisms that reproduce by
sexual means (recombining DNA from both parents), the resulting offspring
almost *always* contains a *new* and unique genome. Mutations also add
information, or modify existing information. Thus, even where the
*quantity* of information remains constant or is reduced, there is often
new information.
But, even where information is measured only in terms of compressibility,
new information can and does appear in offspring genomes. That is,
complexity, as measured by any means of compressing that we have so far
found, will be greater in some offspring genomes than in the parent genome,
even without replication-by-DNA-recombination.
Is the "meaning" meaning of "information" relevant? Yes, because the
replication process involves a translating process in which the
"informational meaning" of genetic material is translated into actual
morphological/physiological features of the organism. One piece of genetic
material, for example, may "mean": make the hair red. Thus, if the
information for making hair red is present but is blocked in expression by
other information that means: "ignore the 'make the hair red' information,"
we will have *more* information in compressibility terms and yet be able to
obtain red hair by *removing* the "ignore . . . " information.
The idea that the information content of a genome is essentially constant
and merely varies slightly from one member of a species to another assumes
that the effective meaning of the information in any given string of base
pairs remains constant. In some cases, it does. But, in others, especially
*short* ones, the meaning may be contextual, and only determinable in the
context of much other information, information that may be different from
organism to organism of the species. Genetic information is only
*partially* "plug-and-play" because of this contextuality. This means, for
example, that two species may have *nearly* all genetic material in common,
but have a small percentage that is different and that determines how a
large portion of the identical genetic material is used.
Finally, genetic comparison of species indicates that some species differ
genetically from earlier species only in terms of a finite number of small
genetic changes, so the conclusion that the later species evolved from a
population of the earlier species, while not thus *proved*, is such an
obviously good one that we should reject it only on the basis of strong
positive evidence against it.
Conclusions and Basic Claims
1. Macroevolution does occur, as an observable phenomenon.
2. Cumulative steps of microevolution do occur.
3. There is no evidence of non-selective and rigid barriers to the
occurrence of multiple cumulative steps of microevolution.
4. We may presume that macroevolution simply *is* multiple cumulative steps
of microevolution, until and unless there is real positive evidence for the
claim of the severe limitedness of cumulative microevolutionary steps.
5. Unless something better in the way of evidence is found against
macroevolution than has so far been offered by ID supporters (such as
Johnson, Behe, et al.), macroevolution stands as, by *far*, the best
explanation for apparent speciation (i.e., that it really *is* speciation).
6. ID remains superfluous. It serves no scientific function better than
NET. This is true even of non-theistic ID, but it is *especially* true of
theistic ID.
Chris Cogan
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