New research has shown that female mammals, including humans, live an average of 12% longer than males. The reasons for this difference in lifespan lie not only in genetics but also in evolutionary reproductive strategies and parental behavior.
Researchers from the Max Planck Institute for Evolutionary Anthropology in Germany analyzed data from 1,176 species of mammals and birds and confirmed that female mammals live longer than males—by an average of 12%. These differences persist regardless of country or historical period, although improvements in living conditions and medicine partially narrow the gap.
Scientists link the longer lifespan of females to genetic characteristics. In mammals, females have two X chromosomes, which offers protection against certain harmful mutations, while males have only one X and one Y chromosome. Conversely, in birds, the situation is reversed: females are the heterogametic sex, and in most cases, males live longer.
Beyond genetics, evolutionary reproductive strategies play a critical role. Male mammals often develop exaggerated mating displays, engage in intense competition for females, and are less involved in raising offspring, which reduces their lifespan. In monogamous species, differences in longevity are less pronounced.
Scientists also note the influence of parental behavior: the sex that actively participates in raising the offspring generally lives longer. Even in zoo environments, where predators and natural dangers are absent, the differences between males and females persist, which confirms the evolutionary nature of this phenomenon.
The study’s conclusion is simple: the longevity of women and female mammals is linked to a combination of genetics, reproductive strategies, and parental role, and not solely to external environmental factors.
