When men and women are subjected to harsh conditions, it’s the women who live longer.
James Vaupel at the University of Southern Denmark in Odense and his colleagues studied seven populations that endured famine, epidemics or enslavement. The researchers found that during crises, girls and women lived longer than their male counterparts. For example, in Ireland during the Great Famine, which lasted from 1845 to 1849, life expectancy dropped from around 38 years for both sexes to about 19 years for men and 22 years for women.
The team traced much of the effect to infancy: newborn girls were more resilient than newborn boys. The minimal behavioural differences between male and female infants suggest that the difference in survival at that age is biological, the authors say.