Baboons that have closer friendships tend to live longer than than those that do not.
Researchers from the Department of Biological Sciences at Notre Dame examined a rich data set outlining the social relationships of wild baboons to see how social interactions influenced their life spans.
"We can tell individual baboons apart by distinct features of their appearance, such as their fur color, the shape of their tail, or how they move. We especially focused on grooming interactions, which are a sign of social support in baboons. Baboons spend more time grooming their 'friends', and baboons with stronger grooming connections seem to live longer," said Elizabeth Archie, Clare Booth Luce Assistant Professor in the Department of Biological Sciences at Notre Dame.
The analysis suggested females who were socially connected to both adult males and other females lived longer to those who had weaker ties. In the future the researchers hope to conduct the same study on males.
"Doing so is difficult because one of the key differences in the lives of male versus female baboons," Archie said, "Specifically, female baboons live in the same social group for their whole lives, so when they disappear from the group, we can be pretty certain that they died. This fact allows us to measure female life spans very accurately. However, male baboons often move repeatedly from one social group to another over the course of their adult life. Hence, if a male baboon disappears from the group, we can't be certain if he died or just moved away, which makes it difficult to measure male life spans."
Multiple studies have implied social relationships have a strong influence on life span in humans, but findings involving other animals have been rare. The lack of research in this field was primarily related to the lack of data available that followed the same individuals over extended periods of time. This new study looked at data from the Amboseli Baboon Research Project, which was collected on a year-round basis since 1984. The findings could be good news for both baboons and their fellow species.
"I think the results are applicable to humans," Archie said. "Specifically, there have been a handful of studies that have shown that an animal's social connections can predict their longevity, including research on rats, dolphins and baboons. Our results help confirm this phenomenon in mammals and suggest it might be widely shared across several social species."
"In addition, we see very strong evidence that social relationships predict human lifespan. Across a range of circumstances, people who receive more social support tend to live longer than people who are socially isolated. Our results suggest that this phenomenon might be part of our shared biological history with other mammals," she concluded.
The findings were published Sept. 9th in the Proceedings of the Royal Society B.
