Cyborg crickets could chirp at the smell of survivors

To the right: Could Modified insects be joining rescue workers in the search for survivors in the future?(Image: KPA/Zuma / Rex Features)

IF you're trapped under rubble after an earthquake, wondering if you'll see daylight again, the last thing you need is an insect buzzing around your face. But that insect could save your life, if a scheme funded by the Pentagon comes off.

The project aims to co-opt the way some insects communicate to give early warning of chemical attacks on the battlefield - the equivalent of the "canary in a coal mine". The researchers behind it say the technology could be put to good use in civilian life, from locating disaster victims to monitoring for pollution and gas leaks, or acting as smoke detectors.

Pentagon-backed researchers have already created insect cyborgs by implanting them with electrodes to control their wing muscles. The latest plan is to create living communication networks by implanting a package of electronics in crickets, cicadas or katydids - all of which communicate via wing-beats. The implants will cause the insects in these OrthopterNets to modulate their calls in the presence of certain chemicals.

"We could do this by adjusting the muscle tension or some other parameter that affects the sound-producing movements. The insect itself might not even notice the modulation," says Ben Epstein of OpCoast, who came up with the idea during a visit to China, where he heard cicadas changing calls in response to each other. The firm, which is based in Point Pleasant Beach, New Jersey, has been awarded a six-month contract to develop a mobile communications network for insects.

As well as a biochemical sensor and a device for modulating the wing muscles, the electronics package would contain an acoustic sensor designed to respond to the altered calls of other insects. This should ensure the "alarm" signal is passed quickly across the network and is ultimately picked up by ground-based transceivers.

The Pentagon's priority is for the insects to detect chemical and biological agents on the battlefield, but Epstein says they could be modified to respond to the scent of humans and thus be used to find survivors of earthquakes and other disasters.

The real challenge will be to miniaturise the electronics. "Given a big enough insect it wouldn't be a problem," says Epstein. But the company is looking at ubiquitous species such as crickets, which tend to be smaller. Each network is likely to use hundreds or thousands of insects, though they could be spread far apart: some katydids can be heard a kilometre away.

Are OrthopterNets feasible? "I don't see why not," says Peter Barnard, director of science at the Royal Entomological Society in London. "Although insects might appear to be limited by the anatomy of their sound-producing organs, we know that they can produce different signals for different purposes." Since there is already evidence of modulation within quite broad bandwidths of frequencies for communication, it might be possible to modify and exploit these abilities, he says.

Originally posted in New scientist