Re: john disects your message!:mutations and reproduction

Steve Clark (ssclark@facstaff.wisc.edu)
Fri, 20 Jun 1997 14:09:12 -0500

At 07:26 PM 6/19/97 -0500, John Queen wrote:
>---I think this discussion goes to the very heart of evolution. Without
>natural selection and random mutations evolution is a sinking ship.
>Natural selection is a theory or idea that will only 'float' if the ideas
>and theories of random mutaions are feasible. The evidence for natural
>selection is the fossil record which is not really evidence for the
>mechanistic aspects of natural selection. In addition, the fossil record
>reveals patterns that natural selection has a hard time explaining. So
>the only real evidence for natural selection is that random mutations can
>contribute to the complexity of a genome thus enabling a selection. This
>in itsself has only be theorized. The evidence for these types of
>mutations is once again the fossil record and the explanation that natural
>selection would pick out the most suited genomes.

There are different types of "evidence" and each has its own level of
convincibility. One works with what is available.

As Mike Behe pointed out in his book, and as John has pointed out in his
recent posts, most of the evidence for evolution is circumstantial and one
would like to see direct mechanistic explanations. The fact that we only
recently began to realize the molecular complexity of cells and tissues
increases the challenge to evolution to explain the origin of these things.
However, we currently have very little understanding of the basic mechanism
by which cells organize themselves, let alone how they gather together to
form functional organs, such as an ear or an eye. Therefore, it is not at
all surprising that we also have very little understanding of any molecular
mechanism that may be responsible for explaining the putative evolutionary
origin of a nucleus (however, there are very sugestive observations
regarding an evolutionary orgin of mitochondria). The whole field of
molecular cell biology is fairly recent and there are very interesting
experiments underway to learn how nuclei assemble, etc. This information
regarding basic molecular cellular processes would seem to be necessary in
order to even ask the simplest questions about molecular mechanisms of
evolution.

I'd be very careful to use the lack of data as proof against the existence
of something.

> I think that much more attention needs to be placed on these two concepts.
> Often textbooks point to the fossils and the pictures without discussing
>the concepts in a manner that is acceptable. Similarities in structures is
>not enough evidence(for me) to except the thought that the two structures
>came from one another over millions of years.
> I appreciate Steves comments because I think he sees where I am coming
>from despite my inability to put into concepts into words. I think that
>evolution relies on these two concepts and that neither are very clear or
>feasible. Thanks for your comments Jim.

I agree with what John writes here. I'd like to see introductory texts do a
better job describing what is and what is not known about evolution, and to
point out the inherent weakness of observations that are consistent with an
hypothesis--that is that such observations are seldom consistent with only
one hypothesis.

This is called good science.

Steve
_________________________________________________________
Steven S. Clark, Ph.D . Phone: 608/263-9137
Associate Professor FAX: 608/263-4226
Dept. of Human Oncology and Email: ssclark@facstaff.wisc.edu
UW Comprehensive Cancer Center
CSC K4-432
600 Highland Ave.
Madison, WI 53792

"It is the glory of God to conceal a matter, but the glory of kings to
search out a matter." Proverbs
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