Scientists recently discovered something about male mice that are completely bananas: the distinctive smell of a banana stresses them out.
Researchers at McGill University in Montreal, Quebec, learned about this aversion to unusual fruit while analyzing stress hormones in male mice when males were close to pregnant or lactating females. Scientists reported in a new study that hormonal changes in men were triggered by the presence of a compound called n-pentyl acetate in women’s urine. It also happens to be the compound that gives bananas their distinctive scent.
“It was all a surprise because we weren’t looking for this in particular and we found it by accident,” said Jeffrey Mogil, lead author of the study and a professor in the psychology department at McGill University. “Pregnant women were in our lab to do another experiment, and one of our undergraduate students noticed that men started acting weird,” Mogil told Live Science.
In the paper, the researchers wrote that “male mice, especially virgin males, are known to engage in infanticide aggression to advance their genetic fitness.” As a way to keep these potential predators at bay, pregnant and lactating females rely on chemo-signaling or emit chemical responses through their bodies to send messages to males to keep them away from their offspring.
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“Rodents and many mammals other than humans depend on their sense of smell,” Mogil said. “Urine odor marking is well known, but what we’ve found here is a new message that has never been described before in mammals. We’ve seen that many olfactory messages are sent from male to female, but there There are fewer examples of women who send them to males Most of these messages have to do with sexual behavior, but in this case, sex has nothing to do with it, females tell males to stay otherwise, be prepared for me to be beaten, and let my puppies touch you. ”
After observing that men’s stress levels were rising in response to women’s urine chemicals, Mogil and his team wondered if n-pentyl acetate from a different source would trigger a similar answer. They bought banana oil at a local supermarket and added the liquid to the cotton balls, which they then placed inside the cages of the male mice. The presence of the odor increased the levels of stress in males in a measurable way, as urine had done in previous experiments, and the researchers suspect that this hormonal peak is directly related to the stress felt when s ‘faces a possible fight.
Exposure to urine or banana oil also had an analgesic or analgesic effect, decreasing men’s sensitivity to pain, the study authors reported. Measured over time, the researchers learned that pain resistance in male mice developed as early as five minutes after smelling n-pentyl acetate and decreased 60 minutes after smelling it.
The study authors also found that stress-induced analgesia levels were significantly higher in virgin male mice, suggesting that unrelated males were greater threats to puppy survival than puppies. pairs. The findings provide insight into the invisible channels of communication that animals use to talk to each other, Mogil told Live Science.
“Mammals are sending more messages to each other than we initially thought,” he said. “We are discovering that their communications are much richer than we give them credit for.”
The findings were published in the journal on May 20 Advances in Science.
Originally published in Live Science.