Biologist Benjamin Mayne certainly generated a lot of media attention with his research showing that the natural human lifespan is 38 years. If he's right, then the implications are huge — for starters, we would have to rethink our entire health care system. That system is based on the (perhaps unrealistic) assumption that deaths not attributable to accident or violence are due to disease, and that all diseases can be conquered with enough medical research.
What if, instead, we're programmed to die before we're even old enough for a midlife crisis?
Not so fast. The 38-year limit comes from a system Mayne and his colleagues created to apply across vertebrates, from the live-fast-die-young forest shrew (2.1 years) to the slow-lane Greenland shark (400 years).