Sperm Wars

October 2, 1996
The major force in the shaping of human sexuality, claims British biologist Baker in this highly unorthodox study, is "sperm warfare," the competition among sperm from two or more men competing inside a woman to fertilize the egg. In this theory, biological imperatives shaped by evolution dictate sexual behavior. Male sexual behavior is driven by each man's need to prevent his female sexual partner from exposing his sperm to competition; or, failing that, to give his sperm the best chance of winning. A woman's sexual behavior, meanwhile, reflects her urge to maneuver her partner or to influence which male's sperm will have the best chance of succeeding. Baker views infidelity, group sex, partner-swapping, even rape and prostitution as risky strategies that nevertheless may enhance an individual's reproductive success compared with long-term monogamy. Men, he says, pursue four reproductive strategies: bisexuality, pursuit or avoidance of sperm warfare and a balancing of this pursuit/avoidance. Just which strategy a male is programmed to adopt will depend largely on his rate of sperm production. Baker's treatise unfolds as a series of graphic, fictional sex scenes, each followed by interpretive commentary. Its reliance on evolutionary biology to explain human behavior is reductionist, much in the manner of the writings of "selfish gene" proponent Richard Dawkins, but it is also challenging, intellectually provocative and likely to raise considerable and deserved debate.