"The courtship chamber was placed on top of an identical chamber, with the chambers separated by muslin gauze," reports geneticist Yael Grosjean in a Methods section fit for a paperback romance. Then the "perfumed" portion of the experiment began. An aphrodisiac scent was presented on the other side of the muslin gauze. Scientists watched to see whether the subject, a male fruit fly, would be compelled to start courting his partner. To ensure that the female wouldn't influence the results with her responses, she had been recently frozen to death.