Once we turn 30, our odds of dying doubles every eight years. The formula that churns out that grim statistic is known as the Gompertz–Makeham law, named after the pair of nineteenth-century actuaries who worked it out, and those odds have remained about the same even as modern medicine has advanced.
Humans aren’t the only ones whose mortality can be summed up by the equation. Although that key age will differ if you’re a mosquito or a horse, nearly all animals see their likelihood of death rise sharply as they get older.
But it’s becoming clear that the Gompertz–Makeham law is not universal. A handful of remarkable creatures don’t appear to age—that is, they show no signs of deterioration as they advance in years. Though they will still perish one day from starvation or predation or freak accidents, their abilities to combat disease and produce offspring endure right up to the end.
How these species manage to dodge the aging process has long baffled scientists, but some are finally beginning to divulge their anti-aging secrets. They are also revealing that there’s more than one way to escape senescence.
