According to a newly published study, moles use stereo smelling to locate their prey, the first example of a creature employing the technique.
While it has long been known that humans and other mammals see and hear in stereo, the new study is the first to suggest that mammals may also have the ability to stereo sniff.
The study, published in the February 5 edition of the journal Nature Communications, details evidence that the common mole (Scalopus aquaticus), smells in stereo in order to hunt its prey. The species of mole is the same one that is commonly thought of as a destructive pest throughout the eastern United States, Canada, and Mexico.
The findings are so groundbreaking that even Kenneth Catania, the leader of the research project, thought they had made a mistake.
“I came at this as a skeptic,” the Stevenson Professor of Biological Sciences at Vanderbilt University said. “I thought the moles’ nostrils were too close together to effectively detect odor gradients.”
Despite his pessimistic first thoughts, Catania pushed on and discovered that moles do, in fact, use stereo sniffing to locate prey. He believes this research could have a big impact on the olfactory studies of other mammals. “The fact that moles use stereo odor cues to locate food suggests other mammals that rely heavily on their sense of smell, like dogs and pigs might also have this ability,” Catania said.
Catania has previously worked with a relative of the common mole, the star-nosed mole. About ten years ago the neuroscientist studied the incredibly sensitive sense of touch of the star-nosed mole. This type of mole is famous for using protuberances of its nose to locate food as it burrows through the Earth. Catania began his research with the common mole as a way to compare the two species of moles’ ability to locate prey.
According to Catania, at first the discovery seemed to raise more questions than answers.
“I expected the common mole, which is virtually blind and doesn’t have a very good sense of touch, to be a lot worse than the star-nosed mole,” he said. “So I was quite surprised when they turned out to be very good at locating prey. At the time, I figured that they must be using their sense of smell, but I didn’t pursue the matter.”
Just a year ago, Catania began researching the common moles sense of smell more extensively. Again, he was surprised at the animal’s incredible ability to locate prey using its sense of smell.
“It was amazing. They found the food in less than five seconds and went directly to the right food well almost every time,” he said. “They have a hyper-sensitive sense of smell.”
Catania was ultimately able to discover that the moles utilize stereo sniffing, meaning they are able to directly locate prey using their sense of smell. He compared the mole’s sense of smell of the barn owl that can locate prey underneath snow by using their extremely sensitive ears