If you've ever worried that an animal could smell your fear, you could be right. You might still be right even if that animal was a fellow human, like your boss or your date.
According to New York Times science columnist Natalie Angier, animals can smell fear in each other. But that doesn't mean they react the way we'd think. The Eurasian roller, a small bird found in Spain, was found to stay away from its nest upon smelling its terrified young's vomit. Lab rats placed downwind of their murine companions imitated any rat they could smell being electrically shocked. And minnows, despite not having noses, know to flee when they sense the pheromones emitted by the skin of an injured compatriot.
Humans aren't immune, either. Test subjects, upon sniffing swabs placed under the armpits of movie-goers, could immediately tell who had seen the scarier film. They labelled the scent as not only stronger, but more "aggressive."
So next time your heart skips a beat at a horror movie, fear not. You can tell if your date is a fellow wimp just by taking a whiff.