Are modern humans the equivalent of super-runners? Natural selection is a kind of selective breeding experiment. Some scientists argue that as the human species evolved, we developed a shared genome that reflects the survival advantage of being able, and willing, to exert ourselves. Maybe everything we know about how movement affects the human brain—from the runner’s high to our ability to get hooked on exercise and the psychological benefits of being active—is proof that, whether or not we have a closet full of sneakers, humans are all, at some level, genetic super-runners.
