MARY LOUISE KELLY, HOST:
Even if you don't own a cat, you've probably seen one flip out over catnip. They roll around on it, rub it on their faces. Then they will sit there in quiet repose, generally acting like they're high. And they kind of are.
ARI SHAPIRO, HOST:
Japanese researchers studied why that happens with a plant called silver vine, native to China and Japan. Professor Masao Miyazaki of Japan's Iwate University says the silver vine plant is unrelated to catnip.
MASAO MIYAZAKI: But the two plant emit very similar structural compound.
KELLY: His team isolated that compound from silver vine, which closely resembles the active chemical in catnip, and found that when sniffed through the nose, the chemical taps into a cat's opioid reward system. Voila - you have a stoned cat.
SHAPIRO: They visited the zoo, too, and found that big cats, like jaguars, lynx and leopards, acted just like kitties when exposed to the chemical.
KELLY: But Miyazaki suspected there might be something more to the attraction.
MIYAZAKI: We think that the response should have other benefit in the cat rather than only getting a euphoria.
KELLY: A tangible benefit, not just euphoria. Well, prior work had suggested these catnip compounds can repel insects. So the scientists tempted house cats to roll and rub against silver vine leaves.
SHAPIRO: And then they unleashed mosquitoes and found that significantly fewer of the biting insects pestered cats who had rubbed against the leaves. The details are in the journal Science Advances.
KELLY: Dr. Mikel Delgado of the University of California at Davis was not involved in the work. She says the finding is intriguing - with a caveat.
MIKEL DELGADO: I would never attribute any type of intention to the cats, that they understand that they are preventing mosquitos like we do when we apply mosquito repellent.
SHAPIRO: Still, she says, even if cats just sniff catnip or silver vine because it makes them feel good, that doesn't negate any unintentional fringe benefits.
DELGADO: Behaviors that are beneficial often feel good, right? Like, mating and eating are things that we do to survive as a species. They also happen to feel good. So there's definitely some overlap between things that benefit you as a species and things that feel good.
KELLY: Now, does this mean we can use catnip as cat mosquito repellent? Not quite, says Delgado.
DELGADO: But it is a nice explanation of a strange behavior that we didn't fully understand before.
SHAPIRO: So that's one strange cat behavior explained - only about a billion more to go.
KELLY: (Laughter).
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