Are Within-sex Mating Strategy Phenotypes an Evolutionary Stable Strategy?

Humans have been found to display considerable variety in their pursuit of mating strategies, varying in their preference for short-term mating encounters versus established long-term relationships. While we know that differences in mating strategy exist between the two sexes (as predicted by parental investment theory), it has recently been shown that each sex may further exhibit two mating phenotypes. Here we explore the possibility that the presence of two phenotypes may be frequency dependent, thus comprising an Evolutionary Stable Strategy (ESS). We suggest that the presence of these phenotypes reflects a compromise between male preference for promiscuity and a female preference in favour of long-term mating by males.