Scientists recently made a strange discovery — the smell of bananas drives male mice, well, bananas.
In a new study published in Science Advances, researchers from McGill University in Montreal, Quebec, found that the scent of bananas creates a stress response in male mice.
The researchers were originally studying how “proximity to pregnant and lactating female mice increased stress hormones in males,” according to Neuroscience News.
“The whole thing came as a surprise, since we were not looking for this in particular and found it by accident,” the study’s senior author, Jeffrey Mogil, told Live Science.
When a grad student noticed that the male mice “began acting weird” around the pregnant female mice in the lab, the researchers discovered that the female mice used “chemosignaling,” or the scent of their urine, to protect their children from predators and infanticide by male mice, Mogil said.
“The females are telling the males to stay away, otherwise be prepared for me to beat the crap out of you if you touch my pups.”
Strangely enough, the compound found in the female mice’s urine — n-pentyl acetate — is the same one that gives bananas their “distinctive smell,” per Live Science.
So the scientists bought banana oil from a local supermarket and put it inside the cages. The stress levels of the male mice then “increased significantly,” according to IFLScience.
“We were able to confirm that the smell of banana extract stressed the male mice just as much as the pregnant females,” Lucas Lima, a co-author of the study, said.