Past research had suggested that information about the local dating pool can influence one’s behavior — exposure to attractive members of one’s own sex can reduce one’s feelings about one’s own attractiveness.

“It’s our belief that religious behavior is linked to several different psychological mechanisms, but one plausible function of religious sanctions on sexuality is to maintain and defend a low-promiscuity, monogamous lifestyle,” said researcher Douglas Kenrick at Arizona State University. “For that lifestyle, an abundance of attractive competitors is a threat.”

“Our guess at this point is that seeing attractive members of one’s sex makes it less likely that you will be able to play a fast and loose mating strategy, because the competition is likely to be too tough,” Li said…

“We are proposing a new way to look at religion — as a strategy to advance evolutionary goals,” Li said.