Todd Greene wrote:
>And this is all beside the primary point, which is
>that there is nothing other than the "microevolutionary"
>processes involved in genetic inheritance in a species
>population, and interactions with other species
>in an ecosystem, that has been yet found to be
>needed to account for evolutionary change.
You will find many evolutionary biologists
disagreeing with you. They would contend that
standard neo-Darwinian theory does not, in
fact, explain macroevolutionary change, because
the former treats types of variation that are
causally insufficient to modify (for instance)
animal morphology in the ways required by the
theory of common descent.
Here's an example, from a new book I highly
"...the evolutionary theory [neo-Darwinism] that
grew up before the advent of regulatory molecular
biology dealt with the problem of the origin of
novel morphological structures in two ways. The
first has been to treat the mechanisms generating
novel morphological structures as a black box.
New forms were considered to arise 'because'
the environment changed. But while changes in
Precambrian or Ordovician weather, continental
shifts, or temperature may have contributed crucial
selective forces, they do not generate heads or
appendicular forms; only genes do that. The
second mode of classical argument was that
organismal evolution is the product of minute
changes in genes and gene products, which
occur as point mutations and which accumulate
little by little, providing the opportunity for
selection and ultimately reproductive isolation.
The major forms this argument has taken have
focused on stepwise, adaptive changes in
protein sequence, but this is probably largely
irrelevant to the evolution of any salient features
of animal morphology (see, e.g., Miklos 1993)."
[from Eric H. Davidson, _Genomic Regulatory
Systems: Development and Evolution_ (New York:
Academic Press, 2001), pp. 19-20]
The molecular geneticist Susan Lindquist at
the University of Chicago tends to begin her
recent major papers with statements to the
effect that "the problem of macroevolution is
unsolved." Such statements are common in
the evolutionary literature. They would not be
so if your argument, namely, that our present
knowledge of microevolution is sufficient to
explain macroevolution, were true.
The Discovery Institute
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