A study has found prairie voles are less stressed and more comfortable when living in close quarters and in close proximity to family and friends. The study is part of a bigger study conducted by Duke University researchers who look into the physiological effects of isolation and crowding in various species, including humans.
Prairie voles are known to be monogamous partners. Their social traits somehow mimic that of humans'. In the study, the researchers monitored the animals' stress levels as they live in varying degrees of isolation and congestion. The team used an enclosure system to group the prairie voles into smaller or larger groups. They tested the feces to track animals' level of corticosterone, the stress hormone.
Radio collars were also used in the study to track movement. The team has found that when the voles lived in congestion with peers, they also bumped into one another more often. But based on their fecal tests, these prairie voles are not stressed out by the collisions with their peers during congestion.
Amazingly, the prairie voles that lived in congestion had the lowest stress levels. The team went further and tripled the amount of voles living in one area, and notably the stress levels reduced all the more by 20 percent.
"Crowding usually forces territorial animals to compete more fiercely for limited supplies of things like food, mates and prime sleeping or nesting spots," said study author and Duke University postdoctoral researcher Dimitri Blondel.
Prairie voles form bonds that last a lifetime. When they live in isolation, they are probably stressed out by thinking how they may be able to find a mate. The animal's population also rises and falls dramatically. This could also be influencing the voles' perception and reaction to crowding.
Due to their "snackable" size, the prairie voles a predator's favorite. When voles sense the decreasing numbers of peers living nearby, it could be a warning sign to them that a predator is on the hunt, which causes the corticosterone to shoot up.
Blondel likened the situation to being stranded on a deserted street during the night. "You might have a higher stress level than if you were in a crowd of 20 people walking down the street," Blondel added. The findings were published in the General and Comparative Endocrinology journal.
