Extinction of larger animals led to the human brain doubling in size around 30,000 years ago

The extinction of large animals led to the human brain growing, a new study reveals. When humans first emerged in Africa 2.6 million years ago the average animal size was more than 1,000 pounds, making them easy prey. Throughout the Pleistocene era, creatures' sizes decreased by 90 percent, which forced our ancient ancestors to developing cunning and bold methods to capture their next meal. As they shifted to hunting small, swift prey animals, humans developed higher cognitive abilities and experienced a growth of brain volume from 650cc to 1,500cc. When humans first emerged in Africa 2.6 million years ago the average animal size was more than 1,000 pounds, making them easy prey Previous research shows that early humans survived by hunting large game, which provided them with the necessary fat and sources of energy to survive.