>In my copy of Origin of Species, natural selection was only one part
>of Darwin's thesis. The other part was that changes ("descent with
>modification") took place gradually over long periods of time. (It
>is this that introduces the notion of "randomness" in evolution).<
Actually, the randomness (in the senses of probabilistic behavior and
of humanly unpredictable events) come from both natural selection and
descent with modification. Natural selection introduces
unpredictability because the environments can vary unpredictably (at
least beyond the capability of most organisms to predict).
Variations include climate change, catastrophes (meteors, volcanos,
etc.), and the evolution of other organisms. The modification in
descent with modification introduces unpredictability because the
occurence of mutations is probabilistic. The interaction between the
two (what mutation happens to interact with what environment) is thus
highly unpredictable without omniscience.
>Basically, I can easily believe Gould's contention that random
>changes tend (in many situations) to be wiped out by natural
>selection and it is the change in the environment that causes an
>evolutionary change to be favored -- not billions of years of a
>"random walk".<
Gould claimed that the vagaries of natural selection made things
random. In fact, his (over IMO)emphasis on the randomness of the
course of evolution led to disagreements with several other workers.
Gould's claims about the extreme variation seen in the Cambrian
explosion appear to be overestimates; ironically, they also appear to
be a major basis for the claims by ID and YEC advocates that the
Cambrian explosion is an example of miraculous creation.
>If there is an elegant way in which God can cause a given outcome it
>could well be something as basic as this: Man is not an accident;
>he is a natural and inevitable result of the environmental
>conditions on this planet as they developed with time. The
>environment and physical laws overrule the randomness,
just as physical laws overpower randomness in other scientific fields.<
Certainly from Genesis we can see that the creation of mankind was
God's intention and thus inevitable. Chaotic (in the mathematical
sense, i.e. deterministic but extremely sensitive to initial
conditions) aspects of the environment and evolution are compatible
with the idea that God set things up just right so that we would
evolve. However, their mathematical intractability probably makes it
impossible to distinguish scientifically between such a model (closer
to the robust formational approach)and a model of God frequently
causing one of multiple possibilities to occur (sort of intermediate,
if these possibilities are all in accord with natural law) or even
subtle miraculous tweaking to bring about a result (an ID model).
Dr. David Campbell
Old Seashells
University of Alabama
Biodiversity & Systematics
Dept. Biological Sciences
Box 870345
Tuscaloosa, AL 35487 USA
bivalve@mail.davidson.alumlink.com
That is Uncle Joe, taken in the masonic regalia of a Grand Exalted
Periwinkle of the Mystic Order of Whelks-P.G. Wodehouse, Romance at
Droitgate Spa
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