A new study, published in Ecology and Evolution , shows that social living is associated with longer lifespan, but also that the benefits of sociality level off once animals move beyond living in pairs.
The researchers behind the study combined large databases of life-history traits, using records of maximum lifespan for each species alongside information on body mass and social organisation. Species were broadly grouped as solitary, pair-living, or group-living.
Lead author of the study is population biologist and Associate Professor Owen R. Jones from Department of Biology at University of Southern Denmark. Co-authors are Kevin Healy from National University of Ireland, Galway and Julia A. Jones, who was at University of Southern Denmark, when the work was done. The study can be found here .
Across mammals, both pair-living and group-living species live longer than solitary ones. However, there is little difference between species with populations organized around a single breeding pair and those living in groups of multiple breeding adults.
According to lead author Owen R. Jones, social organisation should be seen as an added layer on top of well-known patterns like body size. “Bigger animals live longer than small,” he says, “but being social seems to pull species upward from the average lifespan expected for their body size.”
Bigger animals live longer because they generally face lower predation risk, allowing natural selection to favor allocation of more resources to maintenance and repair, thereby extending their lifespans.
The study’s findings point to a balance of benefits and costs associated with living with others. One major advantage is protection against predators.
“The big one is defence against predation,” Jones says, “Social species – whether pairs or groups – benefit from increased vigilance. If you watch deer in a field, there’s almost always at least one individual with its head up, scanning for danger. There is also the dilution effect, where the chance of being caught decreases when there are multiple targets.”
But group-living also comes with downsides. Chief among them is a higher risk of infectious diseases spreading between individuals – a cost that may offset the longevity benefits of multi-adult social structures.
“The larger the group is, the higher risk of pathogen transmission,” he says.
This trade-off may help explain why group-living species do not show further increases in lifespan compared with pair-living species.
The study also explored other factors, such as whether animals are active during the day or night, but found only weak or uncertain effects on lifespan compared with body size and social organisation.
The longevity data used in the analysis come from maximum recorded ages for each species, based on a mix of observations from wild populations and animals under human care.
By showing that social behavior is linked to lifespan across species, the study highlights how behavior, physiology and evolution are deeply intertwined.
“We often think of ageing as pure biology at the cellular level,” Jones says. “But we show that behavior and social life matter too. Over evolutionary time, living together changes how species allocate energy to maintenance, disease resistance and reproduction – and those changes become built into their physiology.”
In their article, the authors conclude, that their results “contribute to a growing understanding of sociality as a key life-history trait that, alongside body size and ecological specialisations, shapes the extraordinary diversity of ageing and longevity strategies across mammals”.
The findings may also resonate beyond mammals.
“In humans, social connections are strongly linked to health and longevity,” Jones says. “Understanding how social organisation shapes lifespan in other animals helps us understand ageing as not just a medical phenomenon.”
“Social Organisation Predicts Lifespan in Mammals”, Ecology and Evolution. Owen R. Jones, Kevin Healy, Julia A. Jones. April 13, 2026. https://onlinelibrary.wiley.com/doi/epdf/10.1002/ece3.73587
Ecology and Evolution
Data/statistical analysis
Animals
Social Organisation Predicts Lifespan in Mammals
13-Apr-2026