When Men Behave Badly: The Hidden Roots of Sexual Deception, Harassment, and Assault

by David M. Buss

Another behavioral marker of the desire for sexual variety is seeking sex outside one’s primary and presumptively monogamous mateship. The famous sexologist Alfred Kinsey found that twice as many men as women had experienced at least one sexual infidelity while married—50 percent versus 26 percent.2 Although women have started to close the gap in recent years, all studies show a sex difference in infidelity rates of at least 10 percent, and most show a larger gap than that. Moreover, men who cheat do so with a larger number of sex partners. Men seeking sex on the side apparently are serial philanderers. Women are choosier even in this domain, typically having a single affair. And of those women, 70 percent cite love or emotional connection as the key reason for the affair, a finding that points less to women’s desire for sexual variety and more to the mate-switching function of infidelity—a topic we take up in Chapter 3. Men’s affairs are more motivated by sex with someone new.