Better, Faster, Stronger: Human Evolution Is Accelerating

In the beginning, there was creationism, which assumed we had never evolved.

Then came the theory of evolution through random mutation and natural selection.

Then came a new hypothesis: Once our ancestors had developed agriculture and stable societies and no longer lived at nature's mercy, human evolution had ceased.

Now we're in the midst of the next mutation in evolutionary theory: Human evolution didn't slow as we advanced from nature to culture. It accelerated and changed. Culture, born of natural selection, became natural selection's driving force.

This is the message of a new study of the human genome. If true, it radically complicates the debate between nature and nurture. The question is no longer simply whether our genes are the source of civilization, but whether they're also its product.

The study, published this week in Proceedings of the Natural Academy of Sciences and based on DNA samples from around the world, concludes that human evolution has accelerated in the last 40,000 years and particularly in the last 10,000. One reason is that population growth has increased the temporal rate of mutations and selections. But in the case of humans, the authors note, "Rapid population growth has been coupled with vast changes in cultures and ecology … creating new opportunities for adaptation." Such "rapid cultural evolution" has "created vastly more opportunities for further genetic change, not fewer, as new avenues emerged for communication, social interactions, and creativity."