Sex, Time, and Power: How Women's Sexuality Shaped Human Evolution

Long ago, due to the narrowness of her bipedal pelvis and the increasing size of her infants’ heads, the human female began to experience high childbirth death rates, precipitating a crisis for the species. Natural selection adapted her to this unique environmental stress by drastically reconfiguring her hormonal reproductive cycle. Her estrus disappeared and menses mysteriously entrained with the periodicity of the moon. Women formulated the concept of a month, which in turn allowed them to make the connection between sex and pregnancy. Upon learning the majestic secret of time these ancestral females then gained the power to refuse sex when they were ovulating. Men were forced to confront women who possessed a mind of their own.

Women taught men about time and the men used this knowledge to become the planet’s most fearsome predator. Unfortunately, they also discovered that they were mortal. Men, then invented religions to soften the certainty of death. Subsequently, they belatedly grasped the function of sex. The possibility of achieving a kind of immortality through heirs drove men to construct patriarchal cultures whose purpose was to control women’s reproductive choices.

Leonard Shlain explores how these archaic insights about sex, time and power dramatically altered all subsequent human cultures, from the nature of courtship to the institution of marriage to the evolution of language. Along the way, the author also offers innovative and provocative theories concerning the human origins of menstrual harmony among closeknit women, homosexuality, superstition, masturbation, early menopause, circumcision, left-handedness, baldness, color blindness, sadism, and orgasms. His book also addresses the reasons why humans have the deepest capacity to love each other over the longest periods of time compared to any other animal. Sex, Time and Power is a compelling book that challenges accepted views of human sexuality and is sure to stimulate new thinking about old matters.

According to Shlain, bipedalism, narrow pelvises, and enormous fetal heads precipitated a crisis for our species. Mothers faced a grave death threat in childbirth. To compensate, women lost estrus and its urgency to copulate, but gained veto power over sex. Drastic reconfiguration of their reproductive cycle, particularly the new feature of heavy menses, allowed women to discover the dimension of time and with it the insight that sex caused pregnancy. Men used foresight to become the planet's most dangerous predator but they suffered terror when they learned they were doomed to die. Inventing religions and afterlives to ameliorate the knowledge of death, men then learned the part they played in impregnation. The concept of paternity drove men to create patriarchal cultures designed to control women's reproductive choice. But the insights, first discovered by women, also created the conditions for two people to love each other more deeply and longer than any other animal.

Throughout Sex, Time, and Power, Shlain offers carefully reasoned and certain to be controversial discussions on subjects such as menses, orgasm, masturbation, menopause, circumcision, male aggression, the evolution of language, homosexuality, and the origin of marriage. Written in a lively and accessible style, Sex, Time, and Power is certain to generate heated debate in the media and among readers interested in human evolution and the history of sexuality.