Dc. Geary, SEXUAL SELECTION, THE DIVISION-OF-LABOR, AND THE EVOLUTION OF SEX-DIFFERENCES - RESPONSE, Behavioral and brain sciences, 21(3), 1998, pp. 444-448
Sexual selection traditionally involves male-male competition and fema
le choice, but in some species, including humans, sexual selection can
also involve female-female competition and male choice. The degree to
which one aspect of sexual selection or another is manifest in human
populations will be influenced by a host of social and ecological vari
ables, including the operational sex ratio. These variables are discus
sed in connection with the relative contribution of sexual selection a
nd the division of labor to the evolution of human sex differences.