Sexual Attractiveness: A Comparative Approach to Morphological, Behavioral and Neurophysiological Aspects of Sexual Signaling in Women and Nonhuman Primate Females

Objective and MethodsThis review focuses on comparative data in nonhuman primates and humans in relation to signaling secondary sex characteristics (SSC), sexual behavior, and neurophysiology of sexuality during the female cycle.ResultsIn monkeys and apes no clear distinction can be drawn between sex as a reproductive, social, or a pleasurable activity. Although female sexual behavior is not limited to a specific phase of the menstrual cycle, changes in body morphology and in behavior and psychology (for example, in feeding, risk taking, and mood) can occur across the cycle. In human and nonhuman primates, homologous biological mechanisms including specific areas of the brain, sex steroids, and receptors are involved in regulating female sexuality. Important aspects of this regulation include the interaction between the subcortical reward system and the social brain network and its projection to the prefrontal cortex. In humans, females advertise SSC permanently after the onset of puberty, but without significant changes across the cycle, whereas in other primate species, female sexual signaling can vary significantly across cycle stages and in fertile and non-fertile phases of the life cycle.ConclusionA great deal is now known about the regulation of female sexuality in primates and the use of sexual signals in terms of their variable expression and their information content for males. Human research has also elucidated the cultural mechanisms through which women communicate about their sexuality, including clothes and make-up. A full understanding of female sexuality in humans, therefore, requires knowledge of culture-biology interactions.