From: LARRY KLAES (ljk4_at_msn.com)
Date: Thu Jan 02 2003 - 08:45:51 PST
----- Original Message -----
From: Bruce Moomaw
Sent: Thursday, January 02, 2003 6:02 AM
To: Europa Icepick
Subject: Musings on evolution
----- Original Message -----
From: "Bruce Moomaw" <moomaw_at_cwnet.com>
To: "Europa Icepick" <europa_at_klx.com>
Sent: Wednesday, January 01, 2003 12:56 PM
Subject: Re: Evidence of Bacteria on Europa?
>
>
> ----- Original Message -----
> From: "Gary McMurtry" <garym_at_iniki.soest.hawaii.edu>
> To: <europa_at_klx.com>
> Sent: Wednesday, January 01, 2003 11:06 AM
> Subject: Re: Evidence of Bacteria on Europa?
>
>
> >
> > Has anyone on this list read "Darwin's Black Box" by Michael Behe
> > (first published in 1996)? It argues quite strongly for intelligent
> > design of complex biochemical systems, like a bacteria's flagellum
> > (an impressive, complex 360 degree rotary engine based upon acid
> > reactions) or the blood clotting mechanism (protein feedback city).
> > Since much of our proposed exploration of Europa is to prove/disprove
> > the ubiquity or uniqueness of life, this work has bearing and must be
> > seriously considered. I'm wondering what Gould's response was to
> > this book?
> ______________
>
> It's gotten stinkeroo reviews from both "Nature" and "Science", but I
don't
> remember the details. I think I have both reviews stuffed in my photocopy
> file, and will dig them out and report later today.
_________________
I found both pieces -- although the "Science" piece is actually a review of
Robert T. Pennock's anthology "Intelligent Design Creationism and Its
Critics", which mentions one essay in that book that is a response to Behe.
First, the "Nature" review of Behe's own book (Sept. 19,1996) by Jerry A.
Coyne of the U. of Chicago. Quoting the most relevant passages:
"Behe's thesis is that organisms harbor molecular pathways so elaborate and
interconnected that they cannot be explained by gradual evolution from
simpler precursors. His examples of such pathways, desribed with admirable
clarity, include blood-clotting, the immune system and intracellular
transport. These share what he cals 'irreducible complexity'; they would
not function if any single component were remoed. Because Darwinism
requires that a pathway be useful at every stage of its evolution, Behe
claims that such irreducible pathways could not evolve in steps. Their
existence therefore implies conscious design and an intelligent creator...
"There is no doubt that the pathways dscribed by Behe are dautingly complex,
and their evolution will be hard to unravel...It is not valid, however, to
assume that, because one man cannot imagine such pathways, they could not
have existed...
"The answer to Behe's argument lies in realizing that biochemical pathways
did not evolve by the sequential addition of steps to pathways that became
functional only at the end. Instead, they have been rigged up with pieces
co-opted from other pathways, duplicated genes and early multifunctional
enzymes. Thrombin, for example, is one of the the key proteins in
blood-clotting, but also acts in cell division, and is related to the
digestive enzyme trypsin. Who knows which function came first? Behe makes
a few half-heareted attempts to build up such pathways, but quickly abandons
the enterprise and cries 'design'.
"Evolutionists will find two other problems with Behe's arguments. First,
there is ample evidence for the evolution of morphology and anatomy from
studies of paleontology, embryology, biogeography and vestigial organs.
Such evolution must, of course, be based on the evolution of molecules and
biochemical pathways. Second, we have plenty of direct evidence for the
evolution of molecules. This includes the remarkable congruence between
phylogenies based on anatomy and those based on DNA or protein sequence
(bats' hemoglobin, for examople, is far more similar to that of whales than
of birds), the relatedness of genes through gene duplication (including
those involved in the immune system and blood-clotting), and the existence
of vestigial 'pseudogenes' that were useful in ancestors. (Unlike most
mammals, humans cannot synthesize vitamin C; we still carry the gene for the
final step in the process, but deletions have rendered it non-functional.)
"Behe's response to these problems constitutes the major weakness of his
theory. He chews on the idea of morphological evolution, but cannot bring
himself to swallow it. He finds the idea of common descent of all organisms
'fairly convincing', and admits that microevolution occurs between species,
but sees no evidence for transitions between major forms. (How one can
admit common descent but deny macroevolution is one of the fascinating
questions Behe leaves unanswered.) Finally, in a tactic unique in the
creationist literature, he admits that BOTH evolution and creation might
occur at the molecular level. Such a hybrid theory, however, yields sterile
offspring, such as Behe's idea that the first 'designed' cell could include
the DNA for all future evolutionary change, including that producing eyes
and the immune system.
"Responding to observations of non-functional genes and inefficient
molecular processes, Behe theorizes that the Great Designer, like his
counterparts in Paris and Milan, has goals beyond functionality: 'Features
that strike us as odd in a design might have been placed there by the
designer for a reason -- for artistic reasons, for variety, to show off, for
some as-yet-undetectable practical purpose, or for some unguessable
reason -- or they might not.' One should add the 'puckish reason': to
confuse future biologists by making things look as though they evolved.
"If one accepts Behe's idea that both evolution and creation can operate
together, and that the Designer's goals are unfathomable, then one confronts
an airtight theory that can't be proved wrong. I can imagine evidence that
would falsify evoluition (a hominid fossil in the Precambrian would do
nicely), but none that could falsify Behe's compound theory. Even if, after
immense effort, we are able to understand the evolution of a complex
biochemical pathway, Behe could simply claim that evidence for design
resides in the other unexplained pathways. Because we will never explain
everyhting, there will always be evidence for design. This regressive ad
hoc creationism may seem clever, but it is certainly not science...
"In the end, 'Darwin's Black Box' is a work of advocacy whose creationist
ancestry is revealed by both its rhetoric and its failure to deal honestly
with the evidence for evolution. There is the usual selective quotation of
evolutionists (including, to my horror, a remark of my own, both altered and
taken out of context), ridicule of scientists, and a folksy 'us-gainst-them'
style reflecting the populist roots of creationism. The book will no doubt
be widely cited by Biblical reationists, who will tout its message of design
while ignoring its timid acceptance of evolution and its view of the creator
as Cosmic Prankster."
As for the review of Pennock's book (which looks very much worth reading) by
Kevin Padian of UC-Berkeley in the March 29, 2002 "Science", there's the
following passage on one essay in it:
"As philosopher of science Philip Kitcher notes, some 'Intelligent Design'
supporters are foxes (they know many things) and some are hedgehogs (they
know only one thing, but it's important). If [creationist author Phillip E.
Johnson] is a fox, then Michael Behe is a hedgehog, because he has made much
of the notion that some biological structures are 'irreducibly complex' and
no intermediates from simpler functional forms are possible. As Kitcher
shows, Behe is saying that because science has yet to solve (or, in some
cases, even study) some problems, they are insoluble -- even though many
problems previously considred insoluble and gaps previously considered
unbridgeable have been solved and bridged. Moreover, evidence of scientific
ignorance is not evidence for creation, which Behe is unable to test in any
empirical sense. Kitcher is equally good at showing how Behe's and
Johnson's books are full of sophistries and cover-ups that deny the truly
impressive evidence of evolution, specific claims of which are explained and
vindicated in the chapter by Matthew Brauer and Daniel Brumbaugh."
Well. As these authors point out, the multiple blind alleys and pointless
dysfunctional mistakes that exist in all living things prove either that
they were designed by an omnipotent being who is a deceptive prankster (in
which case, as philosophers have pointed out, we don't know ANYTHING, since
He could have created the entire universe and us a split-second ago,
cramming us with false memories and it with false physical evidence of a
non-existent past) -- or by a non-omnipotent being or force who is trying to
form matter into more complex living forms but is constantly being
interfered with by other disorganizing and destructive material forces
(Tennyson's "lesser god" who doesn't have the power to completely mold the
world the way He wants to). This last possibility -- similar to theological
dualism, in which there are gods of both Good and Evil influencing the
universe -- is not one that can be completely ruled out. But, as the
authors above show, the trouble is that it's extremely hard -- and maybe
impossible -- to ever prove or disprove the idea, and certainly the current
scientific evidence is inadequate to do so. And science advances --
successfully, up to now -- by assuming that there ARE non-theistic
explanations of all natural processes and trying to find out what they are.
Personally, I have serious doubts on philosophical grounds about what might
be called "pure" or "naive Darwinism" -- both on ethical grounds (Darwinism
in its purely mechanistic form doesn't provide any philosophical
justification at all for behaving morally when you don't happen to feel like
it at the monent, as all of us very often do) and epistemological grounds
(if you assume that the human brain and mind were molded ENTIRELY by blind
outside physical forces, then -- once again -- you have absolutely no basis
on which to assume that your senses, memories and thought processes
themselves are usually correct in what they tell you about the nature of the
world, as opposed to their being total hallucinations and irrational mental
ravings). The Vatican, in its recent surprisingly sensible encyclical on
evolution, uses this same reasoning to argue that Darwinian evolution can
explain everything about living things EXCEPT the human moral sense, and I'm
inclined to agree -- on philosophical grounds, something else must have been
stirred into the mix.
But these arguments only apply to the details of the structure and nature of
the human (and animal) brain and the mind linked to it. (I suspect that
these problems are related to the phenomena of quantum physics -- the one
category of physical phenomena discovered thus far that are NOT purely
clockwork-mechanistic -- and that the biggest scientific surprise of this
century will be the revelation that quantum phenomena are not all as purely
random as current physics states, and tht the non-random ones are intimtely
linked with mental activities.) At any rate, Behe's argument seems totally
inadequate in disproving purely Darwinian evolution on more brutally direct
and obvious physical grounds.
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