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For years, pilots flying into combat have jammed enemy radar to confuse or sneak up on their opponents - and it turns out moths do this too.

Hawkmoths in Borneo have been found to emit sonic pulses, generated by rubbing their genitals on their abdomens, in response to the high-frequency sounds created by bats.

Bats use this echolocation to pinpoint, with great precision, the location of its prey, but the pulses are thought to 'jam' these signals to confuse and disorientate the mammals.

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Hawkmoths in Borneo (left) create sonic pulses by rubbing their genitals on their abdomens. These pulses are designed to respond to high-frequency sounds created by bats (right). Bats use echolocation to pinpoint, with precision, the location of prey, but the pulses are thought to 'jam' these signals to confuse the mammals

'Bats and moths have been engaged in aerial warfare for nearly 65 million years,' explained assistant professor Jesse Barber from Boise State University.

'This arms race has produced a suite of counter-adaptations in moths, including bat-detecting ears.

'One set of defensive strategies involves the active production of sound; ultrasonic replies to bat attack have been shown to startle bats, warn the predators of bad taste and jam their biosonar.'

Professor Barber, alongside co-author Akito Kawahara from the University of Florida, have been studying this behaviour in Malaysia.

By tethering a hawkmoth to a wire, and releasing a bat into a controlled environment, the team were able to track the movements and sounds of both using cameras and high-definition microphones.

It was previously known that tiger moths exhibit a similar defensive strategy - using tymbals, a vibrating membrane located on the thorax - but this genital technique was the first time it was observed in hawkmoths.

Slow-motion videos revealed that males make the noise by grating modified scraper scales on the outside of the 'claspers' against the abdomen.

These claspers, or genital valves, are typically used to grab females during mating.

However, it is thought that females also produce ultrasound in response to an echolocation attack.

They appear to pull part of their genitalia towards their bodies, so the genital scales also rub against their abdomens.

The study is published in Biology Letters, a journal of the Royal Society, and footage of the moths and bats in action features on Sir David Attenborough's upcoming Conquest of the Skies series.

Male hawkmoth produces ultrasound with his GENITALS

Slow-motion videos reveal males make the noise by grating modified scraper scales on the outside of the 'claspers' against the abdomen (pictured bottom). While females appear to pull part of their genitalia towards their bodies, so the genital scales also rub against their abdomens. A recording of the signal is pictured top

'This is just the first step toward understanding a really interesting system,' Professor Kawahara said.

'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 are among the fastest and most proficient flying insects, and more than 1,400 species can be found worldwide.

Their long proboscis, or mouthpart, makes them important pollinators and many plants may only be pollinated by hawkmoths.

This recording shows the hawkmoth responding to playback of a bat echolocation attack. Hawkmoths are among the fastest and most proficient flying insects, and more than 1,400 species can be found worldwide

Female hawkmoth uses genitals to produce anti-bat ultrasound

'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,' Professor Kawahara continued.

'Hawkmoths have evolved different ways of avoiding bats - I can't even explain how amazing the system is, it is just fascinating.'

The Conquest of the Skies 3D series details the evolution of flight and also reveals how flies perform acrobatics in mid-air, how dragonflies use four wings, and how hummingbirds are able to fly sideways.

The series starts 7pm, New Year's Day, Sky 3D and in 2D on Sky 1.

'The story of evolutionary flight is one I've always wanted to tell in 3D,' said Sir David. 'It's a wonderful subject and a very exciting project but technically it is a huge challenge, especially in 3D.'

The Conquest of the Skies series details the evolution of flight and also reveals how flies perform acrobatics in mid-air, how dragonflies use four wings, and how hummingbirds fly sideways. Sir David Attenborough is pictured, hoisted 250ft (7.6 metres) in the air, while filming the bats in the Gomantong cave in Borneo