>Again, it appears to me that we are no further forward regarding the
>matter of the missing transitional forms than was Charles Darwin. As I
>suggested in my last communication, I believe the very concept of an
>'intermediate' is flawed - and the fact that undisputed examples are
>missing from the geologic column (where they should be found in
>abundance!) comes as no surprise. Can you really imagine that a fin on
>the way to becoming a leg offers an advantage to a fish - a creature so
>perfectly tailored to its environment?
This statement reveals a gross misunderstanding that is too often expounded
by critics of the theory of evolution. The critics only seem to understand
one part of the theory of natural selection. The part that they seem to
grasp is that significant phenotypic deviance in an organism may often be
deleterious (i.e., negative selection). However, this represents an
incomplete rendering of the theory. It must be kept in mind that such
changes in phenotype can only be deleterious or advantageous depending on
the context of the particular environment in which the organism finds
itself. Thus, while a significant phenotypic deviation from the norm may
be lethal to most organisms found in their normal environment, the same
change may be advantageous to an organism in a different environment (i.e.,
positive selection). In other words, the critics envision negative
selection and stop there. Of course this truncated view of evolution would
cause the critic conceptual difficulty with the theory.
The theory of evolution posits that the ENVIRONMENTAL CONTEXT determines
whether a phenotypic change will be useful or not, or indeed whether the
common phenotype of an organism continues to be useful. Since Vernon does
not know the environment in which his fish exists, he cannot be confident
that a fin on its way to becoming a leg did not offer an advantage.
Cheers,
Steve
++++++++++++++++++++++++++++++++++++++++++++++++
Steven S. Clark, Ph.D. Ph: 608-263-9137
Associate Professor FAX: 263-4226
Dept. of Human Oncology ssclark@facstaff.wisc.edu
University of Wisconsin
School of Medicine
600 Highland Ave
Madison, WI 53792
http://www1.bocklabs.wisc.edu/profiles/Clark,Steven.html