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Military and police dogs can help neutralize threats or help sniff them out, and that's what the Navy is investing in - a dog's sense of smell. For years, the military has tried to replicate it. The Navy's funding focuses on training dogs to recognize improvised explosive devices or IEDs, which is difficult, as Jimmy Jenkins reports from member station KJZZ.
JIMMY JENKINS, BYLINE: Rohan is a small, black-and-brown shelter dog with perky ears and earnest eyes. He's at the Canine Science Lab on the campus of Arizona State University, getting ready for his test.
NATHAN HALL: All right. So he stuck his nose in. That's triggering the start of a trial. Now he had an itch, so that trial got canceled.
JENKINS: Researcher Nathan Hall is watching as Rohan puts his pointy black nose into a machine that can present thousands of scent mixtures - everything from vanilla to ammonium nitrate. It's called an olfactometer.
HALL: Now he's triggering the new trial. Odor is being presented.
JENKINS: As Rohan keeps his nose in the olfactometer, a computer directs scents to an odor port where he can sniff them. If he smells the target odor, he keeps his nose in. If he doesn't, he takes his nose out.
HALL: He's keeping his nose in, and he gets food for that. That was a correct hit. That was a hit response. The odor was there. He made the correct indication.
JENKINS: Hall is part of a team studying how to train dogs to identify a wide variety of ingredients that could be used to make bombs. Clive Wynne directs the study which is funded by the Office of Naval Research.
CLIVE WYNNE: So we're now asking dogs not just to find a needle in a haystack. Now the problem is more like saying to the dog, we need you to find any sharp object in the haystack.
JENKINS: The dogs not only have to detect whether explosive ingredients are present. They also have to determine if the agents they smell could combine to form an explosive mixture. Wynne says history shows that some of those ingredients don't seem dangerous at all.
WYNNE: I grew up in Britain, and when I was a child, there was a series of terrorist attacks on Britain. And I only recently learned that the critical explosive fuel was confectioner's sugar. Now, would there be a purpose in training dogs to find confectioner's sugar - obviously not.
JENKINS: But Wynne says that dogs need to learn that when combined with other elements, even sugar could be used in a bomb.
WYNNE: We want the dogs to grasp the concept of - this might go bang, and we do that not by showing the dog one explosive and one not explosive smell but by showing the dog thousands of different explosive smells and thousands of different nonexplosive smells.
JENKINS: It's a much different approach than just teaching dogs to detect explosives like TNT or C4. Joong Kim is a program manager with the Office of Naval Research. He says dogs used by the Marines are having a difficult time finding roadside bombs in Iraq and Afghanistan.
JOONG KIM: Their components can be in a different ratio, different quality, and that does seem to have some effect on performance of the canine.
JENKINS: Kim says the big problem is that IEDs are just that - improvised and completely inconsistent.
KIM: That variation is actually the challenging part of being able to identify and locate those threats.
JENKINS: Back at the lab, Rohan takes a break from the trials to check out my microphone. Lab director Clive Wynne says Rohan's nose is over a thousand times more powerful than a human's nose.
WYNNE: United States defense research agencies spent billions of dollars over the last 15 years trying to create a technological replacement for the nose of the dog. And at the end of all that, they just had to admit, no, we cannot get close.
JENKINS: Wynne thinks his team can develop bomb-sniffing dogs that can detect IEDs at a fraction of that price. All it takes is patience and a little positive reinforcement.
Good boy, Rohan. Good Boy.
For NPR News, I'm Jimmy Jenkins in Phoenix.
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