July 1, 2006 If rewarded with sugary water, wasps can be trained in minutes to follow specific smells. The olfactory sensors in their antennae can sense chemicals in the air in concentrations as tiny as a few parts per billion. Wasps could be cost-effective helpers in searching for explosives, toxic chemicals, and even fungi on crops.
Wasps are not man's best friend -- probably their worst. But when it comes to sniffing out trouble, scientists believe they may be better than dogs.
They ward off intruders, track down criminals, find bombs and detect toxic chemicals, but dogs could soon be replaced by wasps. They have the same sensitive odor detection as dogs and are now being trained to sniff out trouble.
"The advantages of a wasp over a dog is you can produce them by the thousands. They are real inexpensive, and you can train them in a matter of minutes," Joe Lewis, a research entomologist at University of Georgia in Athens, tells DBIS.
He and Biological and agricultural engineer Glen Rains are doing just that. Olfactory sensors on the wasps' antennae can smell chemicals in concentrations as tiny as a few parts per billion in the air.
"So far, they've been able to detect, to some level, any chemical that we've trained them to," Rains tells DBIS.
Training is simple and quick. The wasps are fed sugar water. At the same time they're introduced to a smell for 10 seconds. The process is repeated two more times.
Lewis says, "We can train a wasp within a matter of 10 to 15 minutes."
For example, a set of wasps is trained to detect the smell of coffee. When they are put into a simple container, a tiny web camera watches their actions. When the smell of orange is pumped into the pipe, nothing. But when it's coffee, the wasps crowd around the smell.
So far, Rains and Lewis have not found anything the wasps cannot be trained to detect. They can be trained to detect everything from drugs to human remains to fungi on crops. They could one day even be able to detect deadly diseases like cancer.
BACKGROUND: Scientists from the University of Georgia and the USDA Agricultural Research Service are training wasps to detect the telltale odors of concealed explosives, drugs and human remains, and possibly one day certain diseases like cancer. They are now investigating whether it is possible to train mosquitoes as living odor detectors as well, and plan to eventually study other insects with excellent sniffing ability, like honeybees and moths.
HOW IT WORKS: The Georgia scientists have built a device they call the Wasp Hound: an odor-detection device that costs around $60. It is made of a small PVC tube containing five wasps that can be trained to detect any target odor within minutes. The device has a fan at the top, which draws odors into the tube through a filter. If the wasps catch a whiff of whatever they've been trained to smell, they crowd around a hole in the filter. A web cam inside the tube is attached to a computer, which alerts the operator to the wasps' reaction with a beep or a flashing light. The Wasp Hound could be used by farmers to monitor crops for diseases and pests; to check for explosives in airport security applications; to help doctors monitor diseases, or even by defense forces searching for buried land mines.
ADVANTAGES: Unlike dogs and the electronic sensors more commonly used today, wasps are cheap and disposable. It costs pennies and takes minutes to train them: Feed them sugar water while introducing them to a target smell for 10 seconds; give them a 30-second break, repeat the process twice more, and they are completely trained to track that single scent.
ABOUT WASPS: Wasps have olfactory sensors on their antennae that they use to stay alive. For instance, one strain of wasp lays its eggs inside a specific variety of caterpillar. The insects are attracted to the caterpillars by chemicals released by plans as the caterpillars much on them -- a type of SOS signal from the plants. This is also how wasps attract mates. Wasps can sense chemicals in concentrations as tiny as a few parts per billion in the air ý the same range to which dogs and chemical sensors are sensitive. Some species can pick up scents at concentrations as low as one part in a thousand billion, which is a hundred thousand times weaker that the concentrations detectable by commercial "electronic noses."