Human Evolution Enters Exciting New Phase
If you could escape the human time scale for a moment, and regard evolution from the perspective of deep time, in which the last 10,000 years are a short chapter in a long saga, you’d say: Things are pretty wild right now. In the most massive study of genetic variation yet, published in Nature, researchers estimated the age of more than one million variants, or changes to our DNA code, found across human populations. The vast majority proved to be quite young. The chronologies tell a story of evolutionary dynamics in recent human history, a period characterized by both narrow reproductive bottlenecks and sudden, enormous population growth.
The evolutionary dynamics of these features resulted in a flood of new genetic variation, accumulating so fast that natural selection hasn’t caught up yet. As a species, we are freshly bursting with the raw material of evolution.