Researchers evaluated the connection between life expectancy and lifespan equality. The former is the average age of death in a population. The latter measures how many deaths occur at an older age. They found that life span equality increases with life expectancy.
“Life expectancy has increased dramatically and still does in many parts of the world,” Colchero said. “But this is not because we have slowed our rate of aging; the reason is that more and more infants, children and young people survive and this brings up the average life expectancy.”
The study shows the relationship between life expectancy and lifespan equality may be universal among primates. It also offers insight into what produces this pattern.
“We observe that not only humans, but also other primate species exposed to different environments, succeed in living longer by reducing infant and juvenile mortality. However, this relationship only holds if we reduce early mortality, and not by reducing the rate of aging,” Colchero said.
Still, the researcher says it’s possible that the aging rate could be reduced.
Colchero said, “medical science has advanced at an unprecedented pace, so maybe science might succeed in achieving what evolution could not.”