Summary: Conflict between the sexes and cooperation
within a sex can alter classic predictions
of mating systems theory
Suzanne H. Alonzo
Department of Ecology and Evolutionary Biology, Yale University,
PO Box 208106, New Haven, CT 06520-8106, USA
Question: How does the inclusion of conflict between the sexes alter classic predictions of
mating systems theory?
Mathematical method: A game theoretical model of male and female behaviour was used
to examine how interactions between the sexes alter the expected distribution of males and
females among reproductive sites.
Assumptions: Male and female fitness are affected by the abundance of resources in a site,
interactions within and between the sexes, expected survival, and reproductive success.
I examine the possibility that interactions with males decrease female survival. Individuals are
assumed to adopt the evolutionarily stable distribution strategy based on expected fitness.
Predictions: The inclusion of conflict between the sexes alters classic predictions of mating
system theory. When the frequency of males in a site affects female survival, neither males nor
females are predicted to exhibit resource matching. Furthermore, conflict between the sexes can
be masked by the effect of resources and even accentuated by positive interactions among