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“Our findings support the theory that, rather than slowing down death, more people are living much longer due to a reduction in mortality at younger ages,” said José Manuel Aburto from Oxford’s Leverhulme Centre for Demographic Science, who analysed age-specific birth and death data spanning centuries and continents.

“We compared birth and death data from humans and non-human primates and found this general pattern of mortality was the same in all of them,” said Aburto. “This suggests that biological, rather than environmental factors, ultimately control longevity.

“The statistics confirmed, individuals live longer as health and living conditions improve which leads to increasing longevity across an entire population. Nevertheless, a steep rise in death rates, as years advance into old age, is clear to see in all species.”

All the datasets examined by Aburto’s teams revealed the same general pattern of mortality: a high risk of death in infancy which rapidly declines in the immature and teenage years, remains low until early adulthood, and then continually rises in advancing age.

“Our findings confirm that, in historical populations, life expectancy was low because many people died young,” said Aburto. “But as medical, social, and environmental improvements continued, life expectancy increased.

“More and more people get to live much longer now. However, the trajectory towards death in old age has not changed,” he added. “This study suggests evolutionary biology trumps everything and, so far, medical advances have been unable to beat these biological constraints.”