On Wed, 8 Nov 1995 10:42:38 -0500 you wrote:
[...]
SJ>Indeed, if "evolution by natural selection is not strictly
>universal", then what has become of the Darwinism that Dawkins
espouses:
>"It is the contention of the Darwinian world-view that...slow,
>gradual, cumulative natural selection is the ultimate explanation for
>our existence...
>...If there are versions of the evolution theory that
>deny slow gradualism, and deny the central role of natural selection,
>they may be true in particular cases.
>If mechanisms other than NS "may be true in particular cases" then
>NS is not "strictly universal".
Agreed. But Dawkins does say that NS has "the central role" in "the
evolution theory".
SJ>...But they cannot be the whole
>truth, for they deny the very heart of the evolution theory, which
>gives it the power to dissolve astronomical improbabilities and
>explain prodigies of apparent miracle." (Dawkins R., "The Blind
>Watchmaker", Penguin: London, 1991, p318)
BH>It's hard to say if Popper would agree about NS playing the
>"central role" in evolutionary theory. I would guess that he
>would say that this claim is possible but has not yet been
>firmly established.
Agreed. But this is fatal to Dawkins' "Blind Watchmaker" gene
selection model.
BH>If you want to find some individuals who do question the central
>role of NS you should try Michael Ho, Peter Saunders, Brian
>Goodwin, Stuart Kauffman and other self-organizationalists.
>They say rather forcefully that NS plays only a minor role
>in macroevolution, especially the origin of novelty.
Not to mention Gould who espouses Species Selection! But one
would question whether the above "self-organizationalists"
theories are "macroevolution". IMHO Dawkins is right, his
Blind Watchmaker model is the only naturalistic theory of
evolution, even in principle:
"Despite the enormous evidentiary problems faced by the blind
watchmaker model of evolution, the model's great virtue is that it
actually does address the main point at issue, which is how a vast
increase in biological complexity might have occurred over time. I
emphasize this virtue because, as we have seen, many popular proofs of
evolution that uncritical Darwinists find completely satisfactory do
not address the complexity question at all. For uncritical Darwinists
who accept the official stereotype, the issue is not complexity or
increase in genetic information, but simply variation. In their
simplistic view, variations in finch beaks constitute "evolution, and
hence illustrate a process capable of evolving a human being from a
bacterial ancestor, when compared to the standard straw-man
alternative that all species were created fixed and immutable a few
thousand years ago.
Dawkins's blind watchmaker model is infinitely preferable to such
oversimplifications, even if it has to make unsupported assumptions
about crucial factors like the frequency of helpful mutations.
Moreover, Dawkins has argued, without serious contradiction as far as
I am aware, that his kind of model is the only naturalistic theory
that can account for biological complexity even in principle. If
rival models of evolution cannot even in principle explain complexity,
Dawkins's blind watchmaker model deserves to be called the theory of
evolution. (Johnson P.E., "Reason in the Balance", InterVarsity
Press: Downers Grove IL, 1995, p83-84).
Unfortunately, it is not borne out by the fossil evidence:
"In the fossil record, paleontologists observe mass extinctions and
the subsequent sudden appearance of new kinds of organisms. They do
not observe new organs like bat wings in the process of gradual
formation, and they do not observe one kind of organism changing into
something fundamentally different through a step-by-step process.
If the fossil record is a reliable guide, "evolution" seems to be a
process in which new forms of life appeared abruptly, remained
fundamentally unchanged throughout their tenure on the earth and then
often became extinct-not because they were gradually supplanted by
improved descendants, but because they were in the wrong ecological
niche at the time of a mass extinction. That is evolution
Gould-style. Because it is derived primarily from observation, rather
than the more abstract theoretical need to account for complex
adaptations, I call it "empirical evolution" to distinguish it from
"blind watchmaker evolution."
The advantage of empirical evolution is that it squares pretty well
with observations. The disadvantage is that it does not explain the
main point that a theory of evolution needs to explain which is the
origin of adaptive complexity. Living organisms are packed with
complex parts that have to work together, and the genetic information
required to keep those parts working properly to serve the needs of
the organism must be enormous. Where did it come from? To stick with
Dawkins's chosen example, how did the bat get its wings, or its
echolocation (bat sonar) system, or its breathing apparatus, or any of
the myriad other complex things that bats need to have? Extinctions
might clear the way for surviving organisms to occupy new
environmental niches, but extinction events only kill, they do not
create."
(Johnson P.E., "Reason in the Balance", InterVarsity Press: Downers
Grove IL, 1995, pp86-87).
It seems that both Dawkins and Gould are both right - about each
others theory being wrong!
God bless.
Stephen
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