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Lecture 8: Intelligent Design
Ills of Neo-Darwinism
As we discussed in the previous lecture, Neo-Darwinist Theory (NDT) placed Darwin's
variations
and natural selection in the genome. That is, it isn't the species that evolves,
its the genes, with numerous examples drawn from fruit fly research, microbiology, etc, where
specific traits are attributed to single mutations of a gene.
The extreme view of this shift in focus is to say
that a human is just a gene's way of replicating itself, as exemplified in the book
"The Selfish Gene". The advantage, for Neo-Darwinism, is that the gene is a finite
collection of DNA, and by concentrating evolution into the gene, one has a conceptually
bounded cellular machine that meets all the requirements of a mechanistic worldview. In a
sense, it condensed all the history of life into the history of the genetic code, it
converted biology into physics. What more could be asked of a theory?
There are a number of problems with Neo-Darwinism, however, both in detail and
in broad brush. The devil is in the details, and it is these that have plagued the theory,
and have only gotten worse with experiment and time. Here's a sampling of the sorts of
issues that have gotten in the way of the theory. Non-genetic material turns out to have
inheritable effects. Genes can be turned on and off by their environment, and those changes
can be inherited too. The majority of the DNA in most higher animals, including man, is
"junk DNA", which is never expressed as proteins. Differentiation, the process by which
a single fertilized egg becomes a fully functioning living organism, appears not to be
controlled solely by genes. In other words, genes are not the driver of your fate, the
captain of your soul.
But more importantly is the broad brush, genes don't vary the way Darwin wanted them to. Certainly the
variation among Galapagos finches (which is NOT speciation, but adaption), could not
account for the evolution of fishes to frogs. Nor could any experiments detect such
major genetic changes, whether natural or induced by gene altering drugs and radiation.
Rather, the gene was shown to be highly conserved, with error rates between 1:billion
and 1:trillion during replication. This error rate is actually necessary, because computer
models show that higher error rates result in debilitating death of the host population.
So using those error rates, one can ask how long it would
take for, say, monkey cytochrome-C DNA to turn into human cytochrome-C DNA. The answer is,
billions of years, far longer than paleontologists have to offer us. And that is assuming
you know where you are going and each mutation advances you in the right direction. It also
assumes that viable intermediate states are possible, and that each mutation was such an
improvement it took hold in the breeding population. As Spetner describes in his book,
"Not by Chance", the above scenario, when all the statistics are put in, demonstrates that
macroevolution is off by orders of magnitude, by factors of billions to trillions or more.
The computer program by Richard Dawkins, a fanatic evolutionist, demonstrates this aptly by
taking 40 iterations of *directed evolution* to reproduce a short phrase "METHINKS IT IS LIKE
A WEASEL". When one plugs in actual numbers for the differences between species, and assume
5 or 10 years per iteration, one sees that even with direction, the timescales are too large,
and if it were by chance, the time required is nearly infinite.
Thus we would have to assume, from the data alone, that something else was making evolution
happen faster than random chance. Note that Spetner is not saying that change or evolution
is not occurring, only that it cannot occur fast enough.
Michael Behe, in his book "Darwin's Black Box", points out that Darwin himself claimed
that if someone were to find an organ that could not develop by gradual steps, but was
too complex to have evolved, then his theory would be proven wrong. Darwin then goes on to
suggest a "possible scenario" for the evolution of the complex eye from a light sensitive
patch of skin, thereby demonstrating,
he thought, the power of evolutionary theory. Actually, he was setting a precedent for what
some have called "evolutionary just-so" stories, like the story of how the elephant got his
trunk. Behe argues that Darwin put a lot of faith in his "black box" of light sensitive skin,
but when molecular biology started to unravel just exactly how the receptors in the eye work,
it turned out to be a Rube Goldberg nightmare of proteins and inhibitors involving 10 separate
steps to make a nerve cell fire. Nor was this the exception, this was the rule. The clotting
of blood requires almost as many steps.
Well why is that a problem? Because if a single step is missing, the whole system doesn't
work. And as atomic physicists can tell you from theory, three-body reactions are just a
whole lot more rare than two-body reactions. As for four-body reactions forget it. And these
are 10-body events, requiring that all 10 pieces show up at the right sequence and time.
Behe calls them "irreducibly complex", examples of systems that cannot have evolved.
A simple explanation of
Last modified, February 8, 2002, RbS