When you talk to a woman in line at the coffee shop, you may walk away thinking she likes you…probably more than she really does. In general, men tend to overestimate women’s interest in them, which explains why so many men who are shot down at the bar just keep on going. Some people blame the media for this, because it depicts men as sexual creatures always on the prowl. More likely, there’s an evolutionary reason that men are hypersensitive to a woman’s signs—whether smiling at you, laughing at your jokes, or even wearing a red dress. When it comes to evolution, reproduction is key. You are better off overestimating a woman’s interest than missing out on a chance to have more children. Embarrassment probably wasn’t a big concern for early humans. You don’t have to head down to the coffee shop to see this in action. It also works in the lab, which is what researchers did in a recent study. They paired men and women together for a few minutes of small talk. Afterwards, the volunteers secretly rated their partner in the study. All of the men overestimated their partner’s interest in them. Some men, however, were bigger offenders: men who admitted to being interested in casual sex or one-night stands; and men who rated themselves as more attractive. Men who were rated by the women as attractive were less likely to overestimate the woman’s interest. The authors think this has to do with the women actually being interested in them. It’s clear, says one of the authors of the study, that women need to be careful what signals they give off, because men will pick up on them like they’re wearing parabolic microphones. Of course, men should also take a step back the next time they think the woman ordering a cappuccino is hitting on them.