In the recordings, the program can listen for the frequency of wing-beats, which varies from species to species and even between males and females of some species, Keogh said. The team describes the new sensor in a paper currently under review by the Journal of Insect Behavior. Using frequency alone, the program can classify an insect with about 80 percent accuracy.
To make the system even more precise, the algorithm can also be programmed to factor in temperature, humidity and other environmental clues as well as behavioral quirks of various insects, like the time of day they are usually active and the height at which they like to bite.
Biodiversity in the insect world is massive and Keogh's team hopes to build a massive collection of identifiable species by enlisting the help of the public, including elementary schools, where each class could collect data on a single species. The researchers are also working to build the sensors out of Legos, which would make them easy to fix in the field and as cheap as a dollar each.
Potential applications are wide-ranging. In the wild, sensors could track bees to help scientists figure out how colony collapse disorder might be spreading. In orchards, the devices could detect when and where crop-eating insects appear so that farmers could immediately respond with targeted spraying.
In the fight against disease, sensors could be used to identify which of the 3,528 species of mosquitoes just flew through the door of a home so that researchers might know whether the kind that spread malaria are around. Only female mosquitoes bite, so the sensors could also be used to pick out and release only the males form a sterilized population -- a technique that has shown promise in causing population numbers to plunge.
In Mali, entomologist Tovi Lehmann hopes the system will help solve a longstanding mystery. Every year, malaria-carrying mosquitoes disappear during the dry season for up to seven months. But as soon as it rains, they show up instantly. Despite using large human search teams as well as dogs trained to sniff out mosquitoes, scientists still haven't figured out where the mosquitoes go when the rains stop.
If the sensors can be built to stand up to harsh conditions, they could reveal where the mosquitoes hide, possibly allowing for total eradication.
"At this point, we are testing a prototype," said Lehmann, of the Laboratory of Malaria and Vector Research at the National Institute of Allergy and Infectious Diseases in Rockville, Maryland. "The promise is great and I am very enthusiastic about it. They just need a little more work to make them field-ready."