Male hawkmoths have evolved specialized genital structures that act as defensive tools against bats. When threatened or during close encounters, the insects can rub scales on their genitalia against parts of their abdomen to generate ultrasonic sounds. The sounds are thought to interfere with the acoustic cues bats use for hunting.
Research highlighted across outlets frames this as an evolutionary arms race in which hawkmoths repeatedly modify their genital anatomy for improved defense. One report emphasizes a specific mechanism—genital rubbing producing ultrasound—while another focuses on broader diversity, describing multiple evolved strategies hawkmoths use with their genitalia to generate bat-deterring ultrasound. Together, the coverage presents hawkmoth genital evolution as a recurring defensive solution shaped by pressure from bat echolocation.
