WORLD (Enmaeya News) – November 4, 2025

An international team of scientists has uncovered new evidence explaining why women generally live longer than men.

Researchers from the Max Planck Institute for Evolutionary Anthropology, working with 15 global partners, analyzed lifespan data from 1,176 mammal and bird species. The study found that the difference between male and female longevity is rooted in evolution and influenced by genetics, mating strategies, and parenting roles.

The study found that female mammals typically live about 13 percent longer than males, while in many bird species, males outlive females by roughly five percent.

Sexual selection and reproductive strategies appear to play a key role: in species where males compete heavily for mates, such as many mammals, males die younger, whereas in monogamous species, particularly among birds, males often enjoy longer lives.

Genetics also contributes. Mammalian females carry two X chromosomes, which may protect them from harmful mutations, whereas males carry one X and one Y chromosome.

The pattern reverses in birds, where females are the heterogametic sex. Parental care further influences longevity, with the sex investing more in raising offspring, often females in mammals, tending to live longer.

Comparisons between wild and zoo populations show that even when environmental risks are minimized, lifespan differences persist, though they are somewhat reduced.

This mirrors human populations, where medical advances and improved living conditions narrow, but do not erase, the gap between men and women.

According to the researchers, these findings suggest that the lifespan gap is not just a product of modern life but a deeply embedded evolutionary trait, likely to continue far into the future.