Researchers have confirmed what porn producers already know: men tend to get turned on by images depicting an environment in which sperm competition is clearly at play (though few, we imagine, think of it in quite these terms). Images and videos showing one woman with multiple males are far more popular on the Internet and in commercial pornography than those depicting one male with multiple females.14 A quick peek at the online offerings at Adult Video Universe lists over nine hundred titles in the Gangbang genre, but only twenty-seven listed under Reverse Gangbang. You do the math. Why would the males in a species that's been wearing the shackles of monogamy for 1.9 million years be sexually excited by scenes of groups of men ejaculating with one or two women?