History of sex

The social construction of sexual behavior—its taboos, regulation, and social and political impact—has had a profound effect on the various cultures of the world since prehistoric times.

The work of Swiss jurist Johann Bachofen made a major impact on the study of the history of sexuality. Many authors, notably Lewis Henry Morgan and Friedrich Engels, were influenced by Bachofen, and criticized Bachofen's ideas on the subject, which were almost entirely drawn from a close reading of ancient mythology. In his 1861 book Mother Right: An Investigation of the Religious and Juridical Character of Matriarchy in the Ancient World Bachofen writes that in the beginning human sexuality was chaotic and promiscuous. This "aphroditic" stage was replaced by a matriarchal "demeteric" stage, which resulted from the mother being the only reliable way of establishing descendants. Only upon the switch to male-enforced monogamy was paternity certainty possible, giving rise to patriarchy - the ultimate "apolloan" stage of humanity. While the views of Bachofen are not based on empirical evidence, they are important because of the impact they made on thinkers to come, especially in the field of cultural anthropology. Modern explanations of the origins of human sexuality are based in evolutionary biology, and specifically the field of human behavioral ecology. Evolutionary biology shows that the human genotype, like that of all other organisms, is the result of those ancestors who reproduced with greater frequency than others. The resultant sexual behavior adaptations are thus not an "attempt" on the part of the individual to maximize reproduction in a given situation - natural selection does not "see" into the future. Instead, current behavior is probably the result of selective forces that occurred in the Pleistocene. For example, a man trying to have sex with many women all while avoiding parental investment is not doing so because he wants to "increase his fitness", but because the psychological framework that evolved and thrived in the Pleistocene never went away.

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