A 72-year-old in today’s Japan has the same odds of dying as a 30-year-old in the preindustrial world. That’s the startling conclusion of a new study that gauges just how far the death rate has fallen in industrialized countries in recent centuries.
“In other words,” the researchers write, ” … 72 is the new 30.”
Humans nowadays survive much longer than our closest living relatives, chimpanzees, which rarely live past 50. Even hunter-gatherers—who often lack the advanced nutrition, modern medicine, and other benefits of industrialized living—have twice the life expectancy at birth as wild chimpanzees.
So what’s changed in us since the days of our ape ancestors? Are we living so much longer mainly because of changes in our lifestyles or because of genetic mutations—in other words, evolution?
Scientists have discovered that the recent shift to modern living far outweighs evolutionary improvements that have built up over thousands of years. For example, most of the change in mortality rates occurred between now and about 1900—just 4 or so of the roughly 8,000 human generations that have ever lived, the study found.
These improvements are unsurprisingly most likely due to lifestyle changes, rather than to any species-wide genetic adaptations. Learn more here.