Adaptationism's Lessons (was Re: Evolution, "adaptation")
Bryant (mycol1@unm.edu)
29 Aug 1996 20:37:39 -0600
This new thread is an attempt to clarify some confusing issues about
adaptationism and Gould's attacks of it. After reading some of my
exchanges with Lenny, I went back and re-read Gould & Lewontin's 1979
essay, "The Spandrels of San Marco and the Panglossian Paradigm: A
Critique of the Adaptationist Programme" (Proc. R. Soc. London, series B,
205: 581-598).
I am now thoroughly convinced that the main thrust of the argument in
that essay is the assertion that adaptationists see wide-spread "perfection"
(current utility/optimality) everywhere. This is simply untrue.
Dawkins, one of the "hyper-"adaptationists Gould so dislikes, has
repeatedly emphasized the role of time lags in evolution.
Helena Cronin (author of the adaptationist _Ant and Peacock_, Cambridge,
1991), summarizes evolutionists' thinking on the matter thusly:
"Organisms inherit adaptations not to their own environments but those of
previous generations--and the two may be crucially different." So much
for current utility and optimality.
Mocking the adaptationist program, Gould & Lewontin quote Voltaire's Dr.
Pangloss, who said "Things cannot be other than they are...
Everything is made for the best purpose. Our noses were made to carry
spectacles..." ...and so on. This is simply not an accurate
characterization of most neo-Darwinians' position (adaptationism).
As Cronin says more articulately than I could, the problem is that
critics "are conflating the claim that natural selection is the only
[creative] evolutionary force with the claim that all characteristics of
organisms must be adaptive" (p. 86).
Bryant
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