Sting Operation Targets Terror explains how wasps can be trained to detect explosives — or just about anything else:
Unlike dogs and electronic sensors currently in use, the wasps are disposable. They cost pennies and take minutes to train.
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They’ve built the Wasp Hound — a $60 odor-detection device made of a small PVC tube containing five wasps.
The Wasp Hound has a fan in 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 flashing light.
The wasps have been trained to detect a range of illegal or dangerous substances, including 2,4-DNT (a chemical in TNT); putricine, which is associated with decaying flesh; and molds that produce poisonous compounds called aflatoxins in foods like peanuts and milk.
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Research showed the wasps could be trained to detect other smells. All it involves, Lewis said, is feeding 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 voilà — trained insects. In this way, each insect can be trained to track a single scent.