Fewer offspring, longer life: The hidden rule of mammal aging

A large international study reveals that mammals tend to live longer when reproduction is suppressed. On average, lifespan increases by about 10 percent, though the reasons differ for males and females. Castrated males avoid the harmful effects of testosterone, while females gain longevity by sidestepping the intense physical demands of pregnancy and nursing. The results underscore a powerful biological trade-off between making offspring and staying alive longer.