Women tend to live longer than men. There are traditional explanations: Men smoke more. They drink more. They tend to engage in riskier behavior.
But the fact that this lifespan gap holds true regardless of country or century indicates something deeper is also at play. A growing body of evidence suggests that women’s relative longevity may derive, in part, from having double X chromosomes, a redundancy that protects them against harmful mutations.
That theory was further bolstered … with the publication of the most sweeping analysis to date of the lifespan differences between males and females in more than 1,000 mammal and bird species.
In men, “if there’s any deleterious mutations or any mutations that will reduce the lifespan, you don’t have a backup,” said Fernando Colchero, who is … with the Max Planck Institute.
Related on the SLP
For their study, Colchero [and] colleagues collected data on the lifespans of 528 mammal species and 648 bird species kept in zoos. The team found that most other mammals are like humans, with the females of nearly three-fourths of mammal species outliving their male counterparts.
