Why Aging Is a Biological Paradox That Dates Back to the Earliest Mammals of the Mesozoic Era

Blake de Pastino of the PBS series EONS explained that aging is a biological paradox, noting that it is an inherited trait dating back to the earliest mammals of the Mesozoic era.

As we get older, our bodies begin to deteriorate, our fertility declines, and, eventually, we die. But while we take it for granted, from an evolutionary perspective, aging is actually something of a paradox. Why would a process like this evolve in the first place, seeing as it is so detrimental to survival and reproduction, and comes with no obvious upsides?

de Pastino also introduced the longevity bottleneck hypothesis by Jao Pedro de Magalhães to explain why mammalian life spans and aging processes differ significantly from those of other vertebrate groups.

The Longevity Bottleneck Hypothesis,  as it’s known, essentially proposes that for our first 100 million years-plus, we mammals lived fast and died young. … We mammals spent the first  two-thirds of our history this way: as short-lived prey in a dangerous world. And the Longevity Bottleneck hypothesis argues that spending so much of our history like this changed how we age, in ways that we’re still constrained by today.