Adaptationism and Optimality

The debate over the relative importance of natural selection as compared
to other forces affecting the evolution of organisms is a long-standing
and central controversy in evolutionary biology. Adaptationism is the
view that natural selection is so important, and nonselective forces so
unimportant, that accurate explanations and predictions of the phenotypes
of organisms can be obtained by simplified models in which selection
is represented and nonselective forces are ignored. Adaptationists
and their critics disagree about this proposition concerning the history
of life, and they also disagree about the methodologies that are needed
to address this biological question. Many questions remain unresolved,
and the terms of the debate are still sometimes unclear.