Feline Obsession With Catnip And Silvervine May Help Keep Bugs Away

It's no secret that (most) cats are obsessed with catnip and a somewhat lesser-known plant called silvervine. The plant materials often provoke a euphoric response in cats, resulting in behaviors like playfulness, meowing, and rolling out. That latter activity — rolling on the silvervine and catnip — may have a secondary, and quite useful, benefit for cats.

Catnip refers to the leaves of the plant Nepeta cataria, which provoke a positive response from most cats. Silvervine, meanwhile, refers to the woody sticks from the plant Actinidia polygama and they produce a similar effect as catnip when presented to cats. Among the behaviors provoked by these substances is rubbing, particularly on the plant matter.

According to a new study out of Japan's Iwate University, this behavior may have evolved for a useful reason: to give the cats natural protection from mosquitoes. Key to the findings is the substance nepetalactol, a plant chemical that produces the euphoric response in cats.

This same substance has been found to have mosquito repellant effects, helping protect cats from these pests when they rub their fur against the plants. This behavior transfers some plant chemical nepetalactone to the fur, with the study noting cats that engaged in this behavior had fewer mosquitos landing on them compared to cats who weren't exposed to the substance.

Research project leader Professor Masao Miyazaki said:

From these results, we found that the cats' reaction to silver vine is chemical defense against mosquitoes, and perhaps against viruses and parasitic insects. This was the most significant finding of our study ... Why is this reaction limited to cats? Why don't non-feline animals react to the plant? To find answers, we want to identify the gene responsible for the reaction.