I just finished reading _Defeating Darwinism_, a book which I found
absolutely fascinating. Incidentally, it contains a very eloquent essay
by Keith.
On Wed, 18 Apr 2001 22:31:15 -0500 kbmill@ksu.edu (Keith B Miller)
writes:
> But these transition are well documented in the fossil record.
One of the questions I had while reading the book was a statement by
Jonathan Wells (pp 137-138): "First, Darwin maintained that major
differences evolve from minor ones. Yet the fossil record shows that all
of the major animal groups appeared at approximately the same time,
without any fossil evidence that they diverged from a common ancestor.
These original groups have since diversified into many subgroups, so the
major differences among animals appeared before the minor ones.
Paleontologists James Valentine and Douglas Erwin call this a 'seeming
paradox,' since in this respect Darwin's theory 'does not accord with the
primary evidence.' "
It doesn't seem to me that this paradox can be completely resolved by
diffusing the "Cambrian Explosion" back into the pre-Cambrian. Valentine
and Erwin made their statement in 1987. Is Wells using outdated
information, or does he see a pattern which is not generally
acknowledged?
A second question along this same line is whether forms which appear to
be transitional are truly so. The book _Of Pandas and People_ shows
silhouettes of three skulls: a Tasmanian wolf, a North American wolf, and
a dog. The cranial-cavity size increases as you go from the Tasmanian
wolf to the dog, suggesting a transitional relationship. However, we
know the Tasmanian wolf was a marsupial, while the other two are
placental mammals. Convergent evolution can produce forms which look
transitional but which we know are not, based upon soft-part anatomy,
which of course is rarely fossilized. Is this factor just generally
ignored by those inferring evolutionary relationships?
Bill Payne
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