Large families and strong social ties may help female rhesus macaques live longer, by reducing their chances of dying by 2.3 percent in one year, reveals a new study.
Scientist from the University of Exeter found those with many close female relatives have better life expectancy.
However, the effect fades with age - suggesting older females learn how to "navigate the social landscape" and have less need for social ties.
Dr Lauren Brent from the University of Exeter in Devon, South West England said our study supports the idea that social ties promote survival.
This adds to a small but growing body of research that helps to explain why animals are social, Brent added.
The researchers used female relatives as a proxy for social ties.
More From This Section
Dr Brent added, "What was particularly interesting was that social ties didn't have survival benefits for older females.
The results suggested that older females manage this - behaving aggressively and spend a lot of time being groomed by others without offering much grooming in return or being the target of aggression themselves.
"Older females were still involved in society but seemed better able pick and choose their involvement. The experience and social skills females gain with age could mean they no longer need to rely on help from their friends to get by," Brent stated.
The team used a large dataset spanning 21 years and including 910 adult female rhesus macaques in Puerto Rico.
They found that each extra female relative reduced a prime-aged female macaque's chances of dying in one year by 2.3 percent.
Dr Brent said such research could be "hugely important in understanding humans".
"Just like these monkeys, we spend a lot of time navigating the social world," she said.
"Humans and macaques last shared a common ancestor about 25 million years ago, and we can take clues from these distant cousins about how humans might have existed in pre-industrial societies.