Adaptationism

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Adaptationism is a set of methods in the evolutionary sciences for distinguishing the products of adaptation from traits that arise through other processes. It is employed in fields such as ethology and evolutionary psychology that are concerned with identifying adaptations. George Williams' Adaptation and Natural Selection was highly influential in its development, defining some of the heuristics, such as complex functional design, used to identify adaptations.

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[edit] Debate

Adaptationism is sometimes characterized by critics as an unsubstantiated assumption that all or most traits are optimal adaptations. Critics (most notably Richard Lewontin and Stephen Jay Gould) contend that the adaptationists (John Maynard Smith, W.D. Hamilton and Richard Dawkins being frequent examples) have over-emphasized the power of natural selection to shape individual traits to an evolutionary optimum, and ignored the role of developmental constraints, and other factors to explain extant morphological and behavioural traits.

Adaptationists are accused by their critics of using ad-hoc "just-so stories" to make their theories unfalsifiable. The critics, in turn, have often been accused of attacking straw men, rather than the actual views of supposed adaptationists.

Adaptationist researchers respond by asserting that they, too, follow George Williams' depiction of adaptation as an "onerous concept" that should only be applied in light of strong evidence. This evidence can be generally characterized as the successful prediction of novel phenomena based on the hypothesis that design details of adaptations should fit a complex evolved design to respond to a specific set of selection pressures. In evolutionary psychology, researchers such as David Buss contend that the bulk of research findings that were uniquely predicted through adaptationist hypothesizing comprise evidence of the methods' validity.

The debate has occasionally been colored by a political subtext, with the Marxist-leaning Lewontin and Gould accusing sociobiologists of employing adaptationist fallacies in supporting socially regressive views of biological determinism. The history of this debate, and others related to it, are covered in detail by Cronin (1992) and Segerstråle (2000). Adaptationists such as Steven Pinker have also suggested that the debate has a strong ad hominem component. Some suggest that the controversy over the relative importance of various factors would be a quiet debate over subtleties if the critics were less prone to caricaturing their opponents[citation needed].

[edit] References

  • Cronin, H. (1992). The Ant and the Peacock: Altruism and Sexual Selection from Darwin to Today. Cambridge: Cambridge University Press. ISBN 0-521-32937-X. 
  • Gould, S.J.; Lewontin, R.C. (1979). "The spandrels of San Marco and the Panglossian paradigm: A critique of the adaptationist programme". Proceedings of the Royal Society of London B 205 (1161): 581-598. ISSN 0080-4649. 
  • Lewontin, R.C. (1979). "Sociobiology as an adaptationist program". Behavioral Science 24: 5-14. doi:10.1002/bs.3830240103. 
  • Lewontin, R.C. (1993). Biology as Ideology: The Doctrine of DNA. New York: Harper Collins. ISBN 0-06-097519-9. 
  • Maynard Smith, J. (1988). Did Darwin get it right? Essays on games, sex and evolution. London: Penguin books. ISBN 0-14-023013-0. 
  • Orzack, S.H.; & Sober, E.R., eds. (2001). Adaptationism and Optimality. Cambridge: Cambridge University Press. ISBN 0-521-59166-X. 
  • Segerstråle, U. (2000). Defenders of the Truth: The Battle for Science in the Sociobiology Debate and Beyond. Oxford: Oxford University Press. ISBN 0-19-850505-1. 
  • Sober, E. (1998). "Six Sayings about Adaptationism", in D. Hull and M. Ruse (eds): The Philosophy of Biology. Oxford: Oxford University Press. ISBN 0-19-875213-x. 

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