The "Wasp Hound" is a device that utilizes trained wasps to detect explosives and other odors. Joe Lewis, research entomologist with the USDA Agriculture Research Service and the Wasp Hound's lead inventor, discusses the device.
MELISSA BLOCK, host: The next generation of bomb or drug-detecting technology could be the      wasp. Scientists are training wasps to detect specific odors.  They train      the insects by exposing them to a target odor and then giving them sugar      water so they associate the smell with their treat.  The researchers have      developed a device called the Wasp Hound.  The wasps are put inside a      plastic cylinder with a vent hole at one end, a fan that pulls air in and      a tiny Web camera inside hooked up to a computer to monitor the wasps'      reaction.  If they detect what they've been trained to smell, they'll      converge around the air hole `like pigs to a trough,' says one of the      inventors, Joe Lewis, who's a research entomologist.  He says the wasps      have been trained to pick up a wide range of smells.</s>Mr. JOE LEWIS (US Department of Agriculture): 24DNT, which is a      breakdown product of TNT; cadaverine, which is a chemical that's      associated with decaying flesh.  For forensic purposes, we've shown that      they show odors associated with marijuana.  In other words, we have found      that they have a very broad sense of detection capabilities; essentially      it's unlimited.</s>MELISSA BLOCK, host: How long does it take to train these wasps to detect these new      smells?</s>Mr. JOE LEWIS (US Department of Agriculture): Well, very quickly.  You can train them in as short a time      as, say, five minutes, because the training protocol is to let them taste      sugar water while they smell an odor.  And you do that for 10 seconds and      repeat it three times with a small break in between, and they've learned      it.</s>MELISSA BLOCK, host: Have you ever found a wasp that just really couldn't learn?</s>Mr. JOE LEWIS (US Department of Agriculture): They all learn.  We have found that some are quick learners      and respond more aggressively than others.</s>MELISSA BLOCK, host: I guess you're working against one fact of nature here, which is      that wasps have a very short life span.  You're not going to have these      detectors with you for that long.</s>Mr. JOE LEWIS (US Department of Agriculture): That is true.  You know, there are advantages and      disadvantages of this compared to, say, a dog.  The advantage is that you      can produce them by the thousands or more, and you can train them quickly      and you can use them in a rather disposable manner.  The disadvantage is      that they don't live long, a couple of weeks.  And we have to deal with      shortcoming, but we can produce them very inexpensively and train them      very quickly.</s>MELISSA BLOCK, host: Mm-hmm.  And you can't rub their bellies.</s>Mr. JOE LEWIS (US Department of Agriculture): Well, it would be a very tedious process.</s>Mr. JOE LEWIS (US Department of Agriculture): And you can't carry them around on a leash.</s>MELISSA BLOCK, host: Is there, do you think, some broader lesson here about insects,      about the power of smell?</s>Mr. JOE LEWIS (US Department of Agriculture): Oh, yes.  There once was a staying `The deeper the well, the      sweeter the honey.'  Indeed, there was a time--and let me say, early in      my profession that if I had talked about insects having this capability,      I would have been laughed out of my profession.</s>MELISSA BLOCK, host: Is that right?</s>Mr. JOE LEWIS (US Department of Agriculture): But as we move along and find what we're seeing, that      learning in this highly sophisticated ability to integrate taste and      smell and to quickly link and utilize these type things is a much      primitive ability than we had imagined.  In their world and on their      territory, they are as sophisticated as we are.  And they've been around      a long, long time.</s>MELISSA BLOCK, host: I'll never look at them quite the same way.</s>Mr. JOE LEWIS (US Department of Agriculture): Each day, I find that I look at them with much greater      respect. In many ways, all these things are rather sacred.</s>MELISSA BLOCK, host: Joe Lewis, thanks very much.</s>Mr. JOE LEWIS (US Department of Agriculture): Yeah.  Well, thank you, Melissa.</s>MELISSA BLOCK, host: Joe Lewis is a research entomologist with the US Department of      Agriculture in Tifton, Georgia.</s>ROBERT SIEGEL (Host): This is NPR, National Public Radio.