The Fast Track to a Big Brain (3rd of 5)
Channel: William H. Calvin
Date: 2017-01-20

The third in a series of lectures on human evolution, this one covering the period of brain enlargement between 2.4 million years ago and agriculture at 12,000 years ago. The brain tripled in size, perhaps because a brush-fire boom-and-bust in their meat supply created an amplifying feedback loop allowing traits to hitchhike.