Dr. Kevin Daly is allergic to moths.
“I’m not a bug lover at all,” admits the 46-year-old professor in his fourth-floor office one recent morning. Which wouldn’t be that odd — except Daly makes a decent living studying moths. Not just studying moths, but training them. He’s got a whole lab full of them. He breeds them, cares for them, studies the neural activity of their olfactory system. All of which requires inordinate amounts of time in the company of bugs. He is serious about moths. So what does he do when he sees one at home? “Like most people, I usually kill it.”
Daly is an enigma. On the one hand, his boyish antics got him kicked out of Catholic school in the sixth grade. On the other, his desire to learn led him to earn a Ph.D. in ethology and evolutionary psychology and ultimately to become a tenured biology professor at West Virginia University. He admits to being hyperactive, but as he leans back in his chair, speaking softly and dressed in a blue T-shirt, dark shorts and no shoes, that assertion can be hard to believe.
But when you’re with Daly, belief is something you just have to leave at the door.
His office, tucked away amid the Appalachian Mountains, is dotted with photos of mushrooms. An issue of National Geographic — with the cover story “Inside Animal Minds” — rests on his desk. A coffee mug with a picture of President Obama’s birth certificate sits on top of a nearby cabinet.
He enjoyed riding motorcycles, but after being hit twice he finally decided to quit. He’s now taken up mountain biking and power walking around his suburban neighborhood for hours on end to release excess energy — kind of like a moth in flight.
Daly wasn’t always interested in moths. He started a little higher on the evolutionary scale, studying primates at the Jane Goodall Institute, but didn’t feel scientifically satisfied. While attending the University of Arizona, some friends brought him out to a desert museum where they were performing experiments on how moths react to certain odors. “The scientific gears instantly started going,” he recalls, and he never looked back.
It turns out male moths will do just about anything to get closer to moths of the fairer sex. As a graduate student, Daly learned to extract pheromone from females and put it in a wind tunnel. The male moths instinctively flew upwind to get to the source of the scent. His next logical question: Could he train the moths to fly upwind to other bouquets?
Daly discovered moths could learn to respond to novel odors when that odor was paired with food. Like Pavlov’s dogs, the moths start feeding behaviors (in this case a surprisingly long "tongue" extends from the moth’s head) when the odor they learned is released. Daly could train moths to respond selectively to odors that predict the presence of food. And perhaps more remarkably, he found he could train them in as little as a single attempt. Some would even remember it for the rest of their lives.
While this sounds like a great parlor trick, it actually has practical implementations. Forensic entomologists, for example, can aid police in determining when a murder occurred based on the evolving odor profile the corpse releases. Hence, as corpses decay, they attract different species of insects at different times. “A dead animal is a bouquet just like Chanel No. 5,” Daly quips.
Daly knew there were certain types of chemicals he could train moths to sniff out. The U.S. Department of Defense decided to fund his research so he could determine whether odors of military interest — chemical compounds commonly found in explosives — can be detected by insects.
So Daly asked what seemed like an obvious question: Can you train a moth to sniff out a bomb?
Daly and his colleagues got to work building a handheld bomb detector, using bathroom plumbing parts they found at Lowe’s. In MacGyver-like fashion, they broke open a computer, grabbed the fan, and mounted it to their new device. That fan drew air over 10 moths mounted inside the device. (Imagine a shoulder-mounted missile launcher, but instead of rockets in the chamber, there are moths.)
Above: The MacGyver-like bomb detector that holds 10 moths.
Below: The schematics for a slimmer version that holds one moth.
They trained half the moths to respond to the dynamite, and the other half were trained to ignore that odor. This way they could be sure to weed out any inaccuracies from false-positive responses. If all 10 responded, you knew it wasn’t what they were looking for.
They tinkered with several odors that would be of interest to drug officials. They even had samples of cocaine in the lab, which the moths failed to pick up. But, Daly says, “I don’t think they’d have any trouble detecting marijuana.”
He opens a PowerPoint presentation on his computer of a recent talk he gave at Wake Forest University. The five-hour car ride to the lecture, with moth larvae riding shotgun, was hellish on his allergies. He shows me an animation of the brain activity of Manduca sexta, one of the world’s largest hawk moths, as if it’s the most exciting movie he’s ever seen.
When I ask about recent studies involving bees, he notes with a dry mix of competiveness and humor, “Bees can’t smell bombs.”
In the end Daly was indeed able to train moths to sniff out bomb odors. The only problem? They’re nowhere near as good at it as dogs. Plus, can you imagine cops roaming airports with PVC pipes stuffed with moths? Well, neither did the Department of Defense.
But don’t feel bad for Daly. It was just his opening act — a prelude to a more ambitious task.
Daly, a father of two, hopes to leave a legacy to the world of science. And he realizes there’s a bigger picture to his research than just moths. Indeed, he tells of a university-wide interdisciplinary project involving departments like physics and pharmaceutical sciences. Their goal? To build an electronic nose.
Sure, it could be used as a prosthetic for patients who can’t smell. But the device could have even larger implications. An electronic nose — trained to sniff certain chemical compounds — could be used to detect land mines, chemical spills, even spoiled food. Like dogs that use olfactory cues, it may even be able to detect certain forms of cancer. “Understanding how olfactory systems work is the first step in replicating what they do.” The National Institutes of Health has now come knocking.
And just like the moths he studies, Daly moves on.