From: Chris Cogan <ccogan@telepath.com>
>Further, though I do not consider myself to be a Darwinist, except in a
>very broad sense, certainly *my* views have been received with skepticism
>by some on this list. You seem to regard Darwinism as the only form of
>purely naturalistic evolutionary theory there is. Evolution as ongoing
>naturalistic variation coupled with ongoing natural selection might be
>broadly considered to be Darwinism, I suppose, but Darwin certainly had no
>currently acceptable idea as to the genetic mechanisms involved because
>genetics was still "dormant" (and did not get permanently established until
>1900).
Could you please clarify what you mean by Darwinism, and in what respect you
disagree with it, as there seems to be a great deal of confusion about this
term.
I think that few people use the term to mean Darwin's understanding of the
process of evolution, because we know now that Darwin got some things wrong,
and, used in this sense, no-one is a Darwinist.
For the record, I use Darwinism to mean the theory that evolution occurred
by purely natural (non-intelligent) processes, and that the processes which
are responsible for the evolution of complexity are random variation and
natural selection.
This definition of Darwinism implies gradualism, in the sense that large
increases in complexity cannot occur in a single generation. However, it's
important to note that we're talking here about genotypic complexity,
because most random variation occurs at the genotypic level, and a small
change in the genotype can result in a big increase in phenotypic
complexity. For example, an organism may have a complex gene which is
unexpressed and a simple mutation may "switch on" this gene. Also (Cliff
please note), the merging of two organisms by symbiosis (as is thought to
have occurred in the evolution of the eukaryotic cell) is not a violation of
gradualism, because it does not involve the creation of new complexity, but
simply the combination of existing complexity from two organisms into one.
Richard Wein (Tich)
This archive was generated by hypermail 2b29 : Sat Aug 26 2000 - 05:46:09 EDT