Saturday, 6 August 2011

Wynne-Edwards regarded groups as a third level of selection - not second.

What exactly got rejected when group selection got rejected in the 1960s? The abridged history that is now standard suggests that Vero C. Wynne-Edwards (1962) specified a previously amorphous reasoning for the good of species or groups and thereby paved the way to its explicit rejection.
“It was this vague good-for-the-species formulation that Wynne-Edwards tried to put on more solid ground with his 1962 book Animal Dispersion in Relation to Social Behaviour.” (Segerstrale 2000, p. 55)

I recently came across the following statement by Wynne-Edwards, which made me pause and wonder whether something got lost by potting history:
1.5. Social evolution and group-selection
It is part of our Darwinian heritage to accept the view that natural selection operates largely or entirely at two levels, discriminating on the one hand in favour of individuals that are better adapted and consequently leave more surviving progeny than their fellows; and on the other hand between one species and another where their interests overlap and conflict, and where one proves more efficient in making a living than the other. Selection at the individual level is often designated as intraspecific, and that at the higher level interspecific. The latter covers a broad range of relationships; it is frequently concerned not so much with ecological overlap between closely allied species in the same genus as with the mutually conflicting needs of two independent predators seeking the same prey, or two unrelated contestants for the same micro-habitat.
Neither of these two categories of selection would be at all effective in eliciting the kind of social adaptations that concern us here." (Wynne-Edwards 1962, p. 18).

Apparently, Wynne-Edwards took two levels of selection, individual and species, as well established within Darwinism and thought he introduced a third level in between. In retrospective, of course, that does not matter because all higher levels of selection got degraded in the 1960s.

P.S.: Mark E. Borrello (2010) provides a nuanced account recommended to anybody interested in this history of the group selection controversy.

References
  • Borrello ME (2010) Evolutionary Restraints. University of Chicago Press, Chicago
  •  Segerstrale U (2000) Defenders of the truth. Oxford University Press, Oxford
  •  Wynne-Edwards VC (1962) Animal Dispersion. Oliver and Boyd, Edinbourgh

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