You may lose your ability to drive or do math in your head after you've downed too many shots. But one skill that doesn't go away is the ability to detect narcissists and psychopaths—at least if you're a women between ages 18 and 26, according to a new study in Personality and Individual Differences.

For the study, University of Liverpool researchers showed 96 women photos of faces. The faces were manipulated to demonstrate varying levels of resemblance to men who scored high for "dark triad" traits—narcissism, psychopathy, and Machiavellianism—on personality tests. Lead author Dr. Gayle Brewer told Broadly that while it's not known which features (if any) correlate with these qualities, people are somehow pretty good at telling who possesses them.

These women were no exception: They judged the psychopathic, Machiavellian, and narcissistic men as more dangerous than the rest, and they were less likely to consider them as short-term partners. This capacity stayed intact whether the women were given alcohol, a placebo, or nothing at all. 

Brewer told Broadly that this sixth sense for psychopaths could be an adaptation that helps women protect themselves. "From an evolutionary perspective, we may be able to pick up that someone is more threatening, less likely to be trusted, or that our psychological or physical safety is at risk," she explained. 

Yet psychopaths have more sexual partners than the rest of the population, according to another study in Personality and Individual Differences. So, while we might be good at detecting psychopaths and narcissists, whether we decide to sleep with them is a different question entirely.