Yes, You Can Judge a Man by the Length of His … Fingers

Can’t figure out whether the guy you’ve been dating is a keeper? Just look at his fingers.

According to a new study out of McGill University (check it out here), men with short index fingers and long ring fingers are, on average, nicer toward women.

Sounds crazy, right? Well, there is actually some interesting science behind this finding: What scientists call “digit ratio”—the length of the index finger divided by the length of the fourth, or ring, finger—is a good indicator of the amount of male hormones, including testosterone, that someone was exposed to in utero.

“When with women, men with smaller ratios were more likely to listen attentively, smile and laugh, compromise, or compliment the other person,” said lead author Debbie Moskowitz, a psychology professor at McGill. The men were also less quarrelsome with women than with men.

(And sorry, guys—just in case you were tempted to check out the fingers of your female dates, researchers say the “digit theory” doesn’t work for women’s hands.)