The human brain got so big because life was tough in ancient Africa

Coping with harsh conditions, rather than social challenges, was chiefly responsible for boosting the size of our brains, a new study has found. The research found'ecological' challenges like finding food and lighting fires boosted the capacity of our ancestors to think ahead. The finding may settle a decades-long debate on the origins of human intelligence and our social relationships, scientists said. The human brain got so big because life was tough on the African savannah around two million years ago, according to new research. The human brain has tripled in size compared to the white matter of our ancestor Australopithecus afarensis, which roamed the Earth more than 3 million years ago.