Evolution doesn’t always mean progress, Evans told me. It means change. And life can change for better or worse. Today, the human body is changing in ways that have nothing to do with the “survival of the fittest.” Instead, we’re adopting and passing down traits that are detrimental to our health. This concept, called dysevolution, was made popular by Harvard biologist Daniel Lieberman, and it explains why our backs ache, feet hurt, and bones are growing more brittle. Dysevolution also helps explain why we’re breathing so poorly. To understand how this all happened, and why, Evans told me, we need to go back in time. Way back. To before Homo sapiens were even sapiens. Strangely, sadly, the same adaptations that would allow our ancestors to outwit, outmaneuver, and outlive other animals—a mastery of fire and processing food, an enormous brain, and the ability to communicate in a vast range of sounds—would obstruct our mouths and throats and make it much harder for us to breathe. This recessed growth would, much later, make us prone to choke on our own bodies when we slept: to snore.* None of this mattered to the early humans, of course. For tens of thousands of years, our ancestors would use their wildly developed heads to breathe just fine. Armed with a nose, a voice, and a supersized brain, humans took over the world.
In the world that we live in today, evolution is no longer that of survival of the fittest. Just like how pets that are “cuter” get to pass on their traits, many of the traits that might affect our health are also passed down. In this book, Nestor first talks about how evolution, and our traits that allowed us to out-survive and outdo other animals also cause us trouble in our modern bodies.
