Wasps trained to sniff out trouble
27 October 2005
Scientists have harnessed wasps' ability to pick out odours and trained them to react to a poison that affects peanuts and corn. Detecting explosives is next on the list. Could these insect sleuths replace the faithful sniffer dog?
Antenna picks up the trail...
In the wild, parasitic wasps use their amazing sense of smell to seek out the caterpillars in which they lay their eggs. Glen Rains and his team have used the wasps' ability to develop a detecting device they call the 'Wasp Hound'.
Dangerous to caterpillars - but harmless to humans - a parasitic wasp called Microplitis lays her egg inside an unfortunate host.
Image: Ralph Underwood/Agriculture and Agri-Food Canada
'We used the name Wasp Hound to indicate the similarities between dogs trained to detect odours and the wasps.'
Glen Rains, inventor of the Wasp Hound, University of Georgia, USA
Glen Rains, inventor of the Wasp Hound, University of Georgia, USA
The Wasp Hound is a cup-shaped device containing a fan, a Web camera and five lively wasps!
Odours waft to the wasps inside through a tiny pinhole.
Odours waft to the wasps inside through a tiny pinhole.
A cupful of sniffer wasps.
Image: Brad Haire/UGA CAES
How does the Wasp Hound work?
If the captive wasps smell the odour they have been trained to recognise, they will crowd around the pinhole. Each second, the camera takes four pictures of their movements inside the cup, and sends the information to a computer.
If the captive wasps smell the odour they have been trained to recognise, they will crowd around the pinhole. Each second, the camera takes four pictures of their movements inside the cup, and sends the information to a computer.
Software then analyses the pattern of dark wasps against the white interior of the cup and produces a graph to show the wasps' response. Within 30 seconds of the wasps picking up a scent, the Wasp Hound handler receives computer confirmation that they've found what the handler was looking for.
Image: Brad Haire/UGA CAES
How do you train a wasp?
Glen Rains trained his wasps to recognise a chemical called 3-octanone. It's a telltale marker of a toxic fungus that infects and ruins corn and peanut crops.
Glen Rains trained his wasps to recognise a chemical called 3-octanone. It's a telltale marker of a toxic fungus that infects and ruins corn and peanut crops.
The odour is passed over the wasps' antennae three times. Each time, they are given sugar water to eat for ten seconds. It only takes five to ten minutes to produce a fully-trained sniffer wasp, but each insect can only learn one odour.
The wasps were trained to sniff out a corn pest.
Image: Larry Rana/USDA
What else could the Wasp Hound be used for?
Not content with tracking toxic fungi, other wasps have also been trained to recognise chemicals including 2,4-DNT, which is used in some explosives.
Not content with tracking toxic fungi, other wasps have also been trained to recognise chemicals including 2,4-DNT, which is used in some explosives.
'We hope to explore some of the medical applications of detecting the chemicals in people's breath that indicate diseases such as lung cancer. We are also investigating forensic applications to detect illegal drugs and grave sites.'
Glen Rains
Glen Rains
Glen Rains, inventor of the Wasp Hound, University of Georgia, USA.
Image: Brad Haire/UGA CAES
Image: Merle Shepard/Coastal Research & Education Center, Charleston, USA
What's next for the Wasp Hound? 'We are hoping to develop a method to train several wasps at once. Currently, each wasp is trained separately, which can be very tedious. We also hope to develop better methods for observing and understanding the wasp's behaviour once it detects a target odour.' Glen Rains |
The wasps are beneficial to farmers so can just be released once their work is done.
They only live for two to three weeks.
They only live for two to three weeks.
Could wasps replace man's best friend?
'It takes eight weeks to train a dog to become an 'Explosives Search Dog'. During the eight weeks the dogs will be taught to search for, find and then indicate the presence of a range of explosive substances.
'It takes eight weeks to train a dog to become an 'Explosives Search Dog'. During the eight weeks the dogs will be taught to search for, find and then indicate the presence of a range of explosive substances.
'Training commences at about twelve months of age and the dogs will, in normal circumstances, work until they are nine years old, when they will retire and live with the handler as a pet.'
Alun Jenkins, Chief Instructor, Metropolitan Police Dog Training Establishment
Alun Jenkins, Chief Instructor, Metropolitan Police Dog Training Establishment
A sniffer dog at work.
Image: Andrew Boyers/AELTC
'My main concern about the Wasp Hound would be about how close the human operator would need to be to the explosive device. Dogs can roam quite long distances when searching, thereby creating a safe distance between any potential explosive device and the handler.'
Alun Jenkins
Alun Jenkins