Sapiens: A Brief History of Humankind

by Yuval Noah Harari

Species that evolved from a common ancestor are bunched together under the heading ‘genus’ (plural genera).

In Homo sapiens, the brain accounts for about 2–3 per cent of total body weight, but it consumes 25 per cent of the body’s energy when the body is at rest. By comparison, the brains of other apes require only 8 per cent of rest-time energy.

And, indeed, compared to other animals, humans are born prematurely, when many of their vital systems are still underdeveloped.

In addition, since humans are born underdeveloped, they can be educated and socialised to a far greater extent than any other animal.

Some scholars believe there is a direct link between the advent of cooking, the shortening of the human intestinal tract, and the growth of the human brain.

The real difference between us and chimpanzees is the mythical glue that binds together large numbers of individuals, families and groups. This glue has made us the masters of creation.

The human collective knows far more today than did the ancient bands. But at the individual level, ancient foragers were the most knowledgeable and skilful people in history.