Hawkmoths Interfere Bats' Sonars With Ultrasound From Genitalia

Hawkmoths have evolved a unique way to combat one of their most feared predators, bats. How, you ask, does the moth combat its 65-million-year-old enemy? Simple, by jamming a bat's echolocation with high-frequency sounds from their genitalia.

"This is just the first step toward understanding a really interesting system," said Akito Kawahara from the Florida Museum of Natural History on the University of Florida campus. "Echolocation research has been focused on porpoises, whales and dolphins. We know some insects produce the sounds, but this discovery in an unrelated animal making ultrasound, potentially to jam the echolocation of bats, is exciting."

Hawkmoths aren't the first type of moth discovered to use ultrasound. Tiger moths do it too, only they use tymbals, a membrane on the thorax. Hawkmoths, however, create ultra sound through their genitals.

The researchers involved in the project propose that the high-frequency sounds are used to warn other one another of predators, and to confuse bats, which use sonar to hunt.

"We think hawkmoths are a primary food source for bats because none appear to be chemically defended, which is why they have evolved anti-bat ultrasound strategies," Kawahara stated. "Hawkmoths have evolved different ways of avoiding bats - I can't even explain how amazing the system is, it is just fascinating."

"So much work has been focused on animals that are active during the day, but there are a lot of really interesting things happening at night, and we just don't know a lot about what is actually going on - because we can't hear or see it. The fascinating part is that there are a lot of new discoveries to be made. It's a totally unknown, unexplored system."

The potential applications in real life include research in radar-jamming systems for defense and military purposes, as well search-and-rescue disaster scenarios. 

You can read the full published study detailing the findings in the journal Biology Letters.