David Buss, a psychology professor at the University of Michigan, is an ambitious evolutionary psychologist. He's also intrigued by possible differences between men and women. You've heard evolutionary arguments of this sort before. Women and men face different problems and opportunities, because of the differences in how they reproduce. Women can have only one baby each nine months, plus recovery time.
Men can have many mo re.
Women face high physical costs during gestation, since they have to lug the fetus around and find and eat extra food to support it. Long ago, before baby bottles and formula, women also had to spend time and caloric energy nursing their babies for many months each. Males and females in other mammalian species differ in the same ways. Biologists have developed theories about how those differences might lead to differences in their sexual behavior. For example, a male who has an innate propensity to mate with many females during their fertile period may have many offspring who survive and inherit the same propensity to mate like crazy.