How moths evolved to fool their enemies’ sonar

A study published in the Proceedings of the National Academy of Sciences (PNAS)  has shed light on the methods used by luna moths to avoid detection from the sonar cries of bats, their main predators.

The researchers, headed by Akito Kawahara of the Florida Museum of Natural History used high-speed infrared videography to show how luna moths spin their hindtails as they fly, in order to deflect echolocation (sonar) attacks by bats and confuse them.

The research team found that luna moths with tails were 47% more likely to survive an attack than moths without tails. Bats targeted the tail during 55% of the interactions, suggesting the moths may lure bats to the tails to make an attack more survivable.

“When you pit long-tailed moths against bats, bats can’t find the moths. They go to the tail instead of the head,” Kawahara said.

Studying the interaction between long-tailed moths and their predators might lead researchers to developing more effective sonar technologies for military use. However, even without military implications, the findings provide fascinating insight into the evolution of luna moths in the face of sonar, one of the most intriguing predatory methods that exists.

“Most people focus on the beautiful things that are around us during the day, but there’s spectacular diversity in the places we cannot easily see, like in the soil, in the deep ocean, or in the night sky –places we really don’t really often think about,” Kawahara said.

“Understanding nocturnal animal interactions is essential at a time when human activities are having major impacts on the natural world.”