Humans are the only species to live in every environmental niche in the world — from the icesheets to the deserts, rainforests to savannahs. As individuals we are rather puny, but when we are socially connected, we are the most dominant species on the planet.
New evidence from stone tools in southern Africa shows these social connections were stronger and wider than we had thought among our ancestors who lived around 65,000 years ago, shortly before the large “out of Africa” migration in which they began to spread across the world.
