> Whether evolution moves towards greater complexity
> is another matter. If the authors maintain that it is an
> established fact that evolution does not move towards increasing
> complexity then I think they are just wrong. My own reading
> indicates that the jury is still out on this question.
What criteria would one use in determining whether, for example,
the earliest vertebrates were less complex than modern organisms?
Are the early creatures' cells supposed to be less complex? Their
skeletons? Their behavior? Isn't it obvious that a level of organic
complexity was established in the Cambrian boom which has not been
surpassed, save for human cultural evolution? Since that mysterious
formative period, there have only been variations on a theme. Obvious
though it is, this view is not promulgated, presumably because it
conflicts with the popular view that evolution is progressive.
> As Terry pointed out, Gould gives a convincing argument that a
> move towards increasing complexity is almost guaranteed during
> the early stages of evolution. Whether this trend continues
> after that is still open.
This seems only trivially true; for surely one must concede that
abiogenesis and its first ramifications must involve an increase
in complexity. And surely subsequent events may go either way.
One might argue that well-developed ecosystems freeze out evolutionary
novelty, as competition is too fierce, and niches are too well-filled,
to allow truly novel mutants to survive their first awkward stages
and gain a foothold.
-- Cliff Lundberg ~ San Francisco ~ cliff@noevalley.com