When and how did the brains of our hominin ancestors become human minds?
When and why did our capacity for language, art, music and dance evolve?
This pathbreaking book proposes that it was the need for early humans to
live in ever-larger social groups over greater distances--the ability to
"think big"--that drove the enlargement of the human brain and the
development of the human mind. This social brain hypothesis, put forward
by evolutionary psychologists such as Robin Dunbar, can be tested
against archaeological and fossil evidence.
The conclusions here--the fruits of over seven years of research--build
on the insight that modern humans live in effective social groups of
about 150 (so-called "Dunbar's number"), some three times the size of
those of apes and our early ancestors. We live in a world dominated by
social networking. Yet our virtual contact lists, whether on Facebook or
Twitter, are on average no bigger than Dunbar's number.