[ExI] Evolution "for the Good of the Group"

[Jef Allbright]

Recommended, highly relevant to much discussion here, but not freely available.

<http://www.americanscientist.org/issues/feature/2008/5/evolution-for-the-good-of-the-group>

- Jef

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The process known as group selection was once accepted unthinkingly,
then was widely discredited; it's time for a more discriminating
assessment

David Sloan Wilson, Edward O. Wilson

The process known as group selection was once a central part of
evolutionary theory. It seemed obvious that evolution would often
favor traits that benefit groups—colonies, flocks, populations, entire
species—rather than individual organisms. For example, groups that
exercise restraint over their reproductive rate might be supposed to
have an advantage over those that overpopulate their territory and
quickly exhaust some critical resource. Later theorists recognized a
flaw in this reasoning: The evolution of traits that involve sharing
or cooperation could be undermined by "cheaters"—individuals who gain
the benefits of group membership without contributing to the common
welfare. After the 1960s, most biologists avoided explanations based
on group selection and tried to describe all evolutionary events in
terms of selection at the level of the individual. However, this
extreme view gives misleading interpretations of many important
biological phenomena. Now a more nuanced theory, generally known as
multilevel selection theory, acknowledges competing selective forces
within and between groups