Sawfly larvae protect themselves by secreting cocktails of unpleasant, volatile chemicals intended to repel predators, particularly ants. Researchers can assess the effectiveness of these defense by staging meetups, so-called bioassays, between prey and predator. But entomologist Jean-Luc Boevé and informatics engineer Rudi Giot have taken a different approach, translating the secretions' chemical composition into sounds, and measuring how humans react.