Researchers at Duke University in Durham, North Carolina, examined three centuries of historical data and discovered that women not only tend to outlive men during normal times, they’re also more likely to survive in crises like famines and epidemics. The research was published in Proceedings of the National Academy of Sciences.
The Duke researchers focused on times when mortality was very high historically. They looked at several groups of people whose life expectancy was 20 years or less – slaves in Trinidad and the United States in the early 1800s, famine victims throughout the world in the 18th, 19th, and 20th centuries, and people living in Iceland during measles epidemics in 1846 and 1882, for example. What they found was that most of the female advantage results from differences in mortality among infants: Baby girls survive difficult conditions better than baby boys.
Today, the average life expectancy for women is higher than for men in most areas of the world – by more than a decade in some countries. Some research suggests this is primarily due to biological advantages, and other studies stress the importance of social factors. The Duke researchers’ conclusion: Survival advantages in females result from complex interactions between biological, environmental, and social factors.