Behavior: The Scent of a Man

That's because the vomeronasal organ, a pheromone-sensitive structure in the nose that's very active in mice, for example, is largely vestigial in humans. Although it now seems that pheromones are somehow involved in arousal, their role could still be minimal. Says Hamer: "They're certainly not as important as they are in the mouse, who can't rely on gawking at cheerleaders to get turned on." Still, there's no harm in taking a sniff next time you meet someone attractive--as long you do it discreetly.