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Re: Evolutionary Theory (was: Topic of the Day #1)




On Sat, 14 Feb 1998, Rob Meyerson wrote:

> However, there is no guarantee on what the "end product" (there is no
>real ending in evolution, barring extinction) will look like.  It may
>turn out that environmental stresses will actually turn that mutation
>into a *detriment*. 

Evolution _is_ more directed than this (or "quasi-directed" as Dawkins
puts it).  This is true at least on the macro scale.  A seeing "end
product" on any "tape rewind" will develop a lens, a set of
photo-receptive sensors, and so on.  A swimming "end-product" will have a
body shape resistant to drag (thus we see a great deal of convergence to
the fish shape--this shape is not a stochastic end-product).  A flying
"end-product" must be able to push against air molecules to lift its own
weight. In any "tape rewinding" if incipient wings do this, then selection
(barring any genetic constraints) will refine the instruments.  It could
be said, then, that the particular trait creates its own environment of
selection.  Too often species are seen as randomized end products of
stochastic environmental--predominantly abiotic--forces.  This has more to
do with pop science than reality.