Moths create own ultrasonic noises in response to bat sonar

Nature : Bats are well known for using ultrasound to locate insects when hunting. Tiger moths are known to use their own ultrasound to try to jam the bats’ sonar. And now three species of hawkmoths have also been revealed to create ultrasound pulses in response to those of bats. Jesse Barber of Boise State University in Idaho and Akito Kawahara of the University of Florida in Gainesville went to Borneo, where they captured male and female members of several species of hawkmoths. They tied the moths into rigs of fishing line harnesses and directed recordings of bat ultrasound at them. Three of the species responded with ultrasound clicks of their own. High-speed video revealed that the males rubbed their grasper limbs—used for holding onto their partners during mating—against their abdomens. The females appeared to rub their genitals against their abdomens. Barber and Kawahara are not sure if the hawkmoths’ ultrasound is used as a warning or as a jamming system. But because both moth species have independently developed similar features, they serve as an example of evolutionary convergence .