Accounts ofhuman evolution tend to highlight a number ofsignificant characteristics as critical in defining humanity including bipedalism (Jolly 1970, Lovejoy 1981, Wheeler 1984), enlarged brains (Falk 1990, Foley 1996), hairlessness (Morris 1963, Schwartz and Rosenblum 1980), and language (pinker and Bloom 1990, Dunbar 1996). Less frequently, scholars have focused on the unique aspects of human sexuality. In this paper, I seek to demonstrate that sexual swellings are not the norm among alloprimates and that the prevailing absence ofestrus among female humans is better viewed as a derived trait which is no more unique than that of any other primate. As such, I would argue, current theories of the"loss" of human estrus should be reevaluated.
Wagener '06, Joshua S., ""Loss of Estrus" and Concealed Ovulation in Human Evolution: A Reevaluation." (2006). Honors Projects. Paper 17.