a hypothesis of female mate selection arguing that certain features of male behavior and body structure reflect genetic variations that are correlated with positive survival attributes such as health and strength and that females choose males with such features, thereby enhancing their offspring’s chances of survival. Compare runaway selection. [proposed in 1982 by British evolutionary biologist William D. Hamilton (1936–2000) and U.S. behavioral ecologist Marlene Zuk (1956– )]