rationalskepticism.org

Men are more violent when there are more women around

More men inevitably means more testosterone-fuelled violence, right? Wrong, according to a comprehensive analysis exploring how a surplus of men or women affect crime rates across the US.

In areas where men outnumber women, there were lower rates of murders and assaults as well as fewer sex-related crimes, such as rapes, sex offences and prostitution. Conversely, higher rates of these crimes occurred in areas where there were more women than men.
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According to Schacht, when women are in short supply, men must be more dutiful to win and retain a partner. With an abundance of women, men are spoilt for choice and adopt more promiscuous behaviour that brings them into conflict with other men, and more likely to commit sex-related offences.

“When women are rare they become a valued resource and this gives them more bargaining power over what they expect from a relationship,” says Schacht. “But when women are abundant, men become less committed to single partners and more interested in pursuing multiple relationships,” he says. “This brings men into conflict with each other in response to their more uncommitted, promiscuous mating orientation.”

The upshot, says Schacht, is that men alter their behaviour to suit conditions of “supply and demand”. “In some situations they will be much better behaved, and in others they will be much more prone to nasty behaviour,” he says.