Long-lived naked mole-rats are eusocial: like ants and bees, they live in colonies led by a queen that is the only female that reproduces. Naked mole-rats are extremely long-lived in comparison to other similarly sized mammals, and this tendency towards greater longevity shows up in many other eusocial species. It crosses evolutionary clades and ecological niches, which might lead one to ask what exactly it is about eusociality that promotes longevity. Here, researchers offer a hypothesis based on modeling.
Animals such as bees, ants, wasps, termites, and naked mole-rats live in colonies in which a single queen is the only female reproductive, an arrangement known as eusociality. Eusocial animals are known for their remarkably long lifespans. It has been argued that longevity becomes selected when queens are shielded from "external mortality". While such protection may contribute, we find a deeper reason: the eusocial reproduction strategy itself inherently creates selection for long lifespans.
Lifespans typically reflect two processes: the baseline risk of death and the rate at which this risk increases with age. Each is a parameter in the Gompertz mortality equation. We show that the mathematical properties of eusocial reproduction lead to slowly-growing, older populations where selection acts more strongly on the rate at which risk increases than on the baseline risk. In addition, we show that channeling reproduction through a single female also selects for longevity, which we term the "queen effect". Thus, the dynamics of eusocial reproduction select for longer lifespan. More broadly, these results show that reproductive structure and population growth dynamics can fundamentally shape selection on lifespan, with implications outside eusocial systems as well.
Link: https://doi.org/10.1101/2025.03.25.645350
View the full article at FightAging
