Trivers-Willard hypothesis

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In evolutionary biology, the Trivers-Willard hypothesis proposes that parents should invest more in the sex that gives them the greatest reproductive payoff (grandchildren) with increasing or "marginal" investment. The hypothesis was used to explain why Red Deer mothers would produce more sons when they are in good condition, and more daughers when in poor condition.

Dominance also affects the sex of their offspring, with dominant females birthing more sons and non-dominant females birthing more daughters.

See also

• Evolution
  • Natural selection
  • Sexual selection
  • Kin selection
• Inclusive fitness
  • Parental investment
  • Parent-offspring conflict
  • Trivers-Willard hypothesis
  • Reciprocal altruism
• Group selection
• Life-history theory

Also, applications to the study of human behavior:

• Dual inheritance theory
• Evolutionary psychology
  • Evolutionary developmental psychology
  • Evolutionary educational psychology
• Human behavioral ecology
• List of publications on evolution and human behavior

References

• Trivers, R.L., & Willard, D.E. (1973). Natural selection of parental ability to vary the sex ratio of offspring. Science, 179, 90-92.

Further reading

• Google Scholar

• Keller, M.C., Nesse, R.M., & Hofferth, S. (2001). The Trivers-Willard hypothesis of parental investment: No effect in the contemporary United States. Evolution and Human Behavior, 22, 343-360. Full text

• Quinlan, R., Quinlan, M. & Flinn, M. (2005). Local Resource Enhancement & Sex-biased Breastfeeding in a Caribbean Community. Current Anthropology, 46, 3, 471-480. Full text