Female rhesus monkeys prioritize friends and family as they age and “actively reduce” their social networks, according to a new study.
The findings, published in the journal PNAS, also suggest that older women are not shunned in their later lives, but that their changes in social circle are driven by themselves.
Having fewer friends in later life is considered harmful, even among humans, due to concerns about social isolation and loneliness in older adults.
But recent studies have suggested that this narrowing of social networks in humans could be proactive and provide benefits in some way.
Researchers at the University of Exeter in the UK have found that macaques also become increasingly selective and focus on long-standing relatives and friendships in later life.
“This pattern of shrinking social networks with age is common in humans. Our study offers the most conclusive evidence to date that social selectivity is not unique to humans, and therefore may have deeper evolutionary underpinnings,” study co-author Lauren Brent said in a statement.
In the research, the scientists studied eight years of data on more than 200 macaques, assessing how each individual’s social life has changed.
They found strong evidence of women’s social selectivity ruling out other explanations such as the death of partners.
“There are many possible reasons why macaques become more socially selective as they age,” said Erin Siracusa, another study author.
“For example, the benefits of social interactions could change over time. Young macaques could benefit from a large social group that can help them explore and find potential mates,” explained Dr Siracusa.
While the women in the study narrowed their network as they aged, the scientists also found that they remained actively engaged in their social world.
“Elderly females remained actively engaged in their social world and spent similar amounts of time grooming, grooming, and sitting near other females.
“So, the social decline wasn’t caused by a lack of interest or an ability to engage,” he added.
For older macaques, researchers suspect it may be easier and safer to stick with existing family and friends for a variety of reasons, including to minimize conflict and reduce disease transmission as their immune systems decline. with age.
“New relationships also require more mental effort, so while we don’t see any decrease in time spent socializing, older macaques could conserve mental energy by reducing their network,” Dr. Siracusa said.
‘Taken together, our results provide rare empirical evidence for social selectivity in non-humans, suggesting that patterns of increasing selectivity with age may be deeply rooted in primate evolution,’ the scientists wrote in the study.