Costs and Benefits of Female Mate Choice: Is There a Lek Paradox?

Abstract

Mate choice in noneconomic mating systems has been considered paradoxical because, relative to economic systems, females were thought to have "highly developed" preferences, despite males' having little to offer. Efforts to resolve this paradox have generally searched for genetic benefits of choice through either "good genes" or "runaway" coevolution. In this paper, we emphasize natural selection acting directly on females and their offspring. We argue that, although females are expected to pay lower costs in noneconomic mating systems, this need not translate into examining fewer males or spending less time in this activity. Furthermore, various direct (nongenetic) benefits may accrue. In species in which males offer benefits that are more variable, such as territories or parental care, females should evolve toward greater investment in mate choice, especially when these resources cannot be shared among females. Any tendency for females to be more selective in noneconomic mating systems, despite lower benefits, can probably be explained if the much lower costs of search, and thus net benefits, are considered. Therefore, there may be no lek paradox.