Evolution of Human Sexuality

In 1895 Breuer and Freud published a book titled Studies in Hysteria that paved the way for a century of psychoanalytic explanations of human behavior. The theme of the explanations is that expressed or repressed sexuality, aggression underlie and direct all human behavior. Indeed, even the most creative acts are viewed as resulting from disguised sexual intentions in the form of sublimation. Although, psychoanalytic theory has largely failed to meet research support, it seems to have stumbled onto a key principle of today’s zeitgeist, evolutionary psychology. Evolutionary psychology supports the idea that sex does permeate most every aspect of our lives. A man does not buy the expensive sports car only because he wants to drive fast. A woman does not dye her hair or buy a snug fitting dress because she wants to look good for herself. Even someone cramming for college entrance exams might be trying to bring his or her grades up for reasons other than college admissions. Entrance into a better school leads to increased income and consequently better access to a mate.

Supporting this perspective, psychologist David Buss theorized that virtually all male violence has a sexual basis. This point was compellingly detailed by authors Malcolm Potts and Thomas Hayden who cogently argue that most wars can be traced to innate sexual competition. This evolutionary perspective of violence is based on both direct and indirect sexual jealousy. Direct sexual jealousy usually involves a male guarding his mate, whereas indirect jealousy extends to encounters that are tangential to the love relationship. For example, the rage a man feels when slighted is abstractly sexual, as it may result in his losing prestige or social standing. Since all men are potential sexual competitors, loss of face typically leads to a diminution in a man’s access to females. Indeed, many evolutionary psychologists opine that homicidal jealousy is an evolutionary adaption since killing a direct or indirect sexual competitor was an efficient solution during human evolution. Why not? There were no jails, lawsuits or any consequences save for revenge by the slain man’s kin. Killing one’s sexual competitor smoothed the path towards passing one’s genes to future generations. In short, evolution may have made it more adaptive to kill than be cuckolded. The need to take an evolutionary view of sex is emphasized by Dobzhansky, who said “nothing in biology makes sense except in the light of evolution. By logical extension it follows that nothing in sexuality makes sense except in light of evolution. Psychologists who attempt to understand and treat couples in distress must at least make an attempt to understand human social behavior in terms of our evolutionary past.