Our big brains evolved not because we were great thinkers, but great runners. The article in the NYTimes adds an interesting twist to the question of how we evolved from our primate ancestors. My interest in anthropology is no more unusual than that of metaphysics in general—what is the nature of reality, or who we are and how we got here.
Our australopithecine ancestors (Google ” Lucy” for further info) found themselves in a progressively changing environment. Tectonic shifts in the African continent, climate change resulted in diminishing jungles. Their protective trees gave way to open savannas with grasslands. They rose up on two legs to survey their landscape. That position enabled them to look at their surroundings, utilize both hands for carrying objects and tool making, and to move relatively long distances in open savannas in order to “run down” and consume swifter prey. This ability to do long distance jogging provided them with the protein infusion, animal protein (sorry to our vegan friends) that promoted brain development.
Our less simian ancestors that came after “Lucy” such as homo habilis and homo erectus evoled this larger brain capacity. But protein was needed to fuel the metabolically active central nervous system characteristic of our lineage and our ancestry.
This process of natural selection would further promote bipedalism, long- distance movement and associated brain development.
This theory fits in well with recent studies demonstrating neurogenesis in adults by virtue of aerobic exercise. In all likelihood it was the younger australopithecines who did the long distance running/hunting. Excessive training was unnecessary. Running was for day to day survival not gold medals. But just perhaps the secondary gain of all this aerobics was the enlargement and improved function of our cerebral cortex.
Of course modern research has demonstrated that excessive aerobics over a period of time is not only not conducive to longevity, but quite the opposite, it is associated with reduced life spans. So once again the “secret” to life is moderation. Exercise was and is important to our collective and individual health. Extreme exercise is not. Our ancestors were successful joggers, not marathon winners.