Large ground squirrels known as yellow-bellied marmots tend to live longer the less social and more isolated they are, according to new research published in the Proceedings of the Royal Society B.
This study comes researchers at the University of California, Los Angeles, who analyzed 66 adult female marmots from 2002 to 2015 at the Rocky Mountain Biological Laboratory in western Colorado. They watched the mammals from afar for six hours a day between mid-April through mid-September and then recorded when they were playing, sitting next to each other, touching, or grooming.
As with most squirrel species, marmots have a wide range of predators. Foxes, coyotes, and bears eat them, and the rodents only have a 50 percent chance to live through their first year of life. However, the ones that make it past that time typically live to between five and seven years. Some have even been known to live twice that long.
When studying the creatures, researchers measured and analyzed their social interactions in comparison to their lifespans. They found that less social marmots lived, on average, over two years longer than social ones.
This is an odd trend, and researchers are not sure how to explain it. They postulate that social interactions could raise a marmot’s risk of getting sick from parasites and fleas, or it could lead to competition for food in times where resources are scarce.
This finding is interesting because, unlike marmots, humans need social interaction. Past research has shown that humans who are social live much longer than those who are not. In fact, people who are less social tend to have the same lifespan as heavy smokers. Similar effects have been found in highly social primates as well.
While scientists are not sure what to make of the marmots, they believe there could be a price to pay for being too social. The study only focused on one species, but scientists plan to expand their research to look at the way such interaction affects other animals.