The control of fire was not a single invention but a habit settling in by degrees: first using natural wildfires, then preserving embers, and finally producing flame at will. There is therefore no single answer to the question of when it began.

The best-documented early evidence comes from Wonderwerk Cave in South Africa, where burnt bone fragments and ash residues, dated to about one million years ago, were recovered from layers deep enough inside the cave to rule out natural fires. Hearths at Gesher Benot Ya'aqov in Israel are dated to 790,000 years ago; more extensive evidence comes from Zhoukoudian in China, around 400,000 years ago. In Europe, the 300,000-year-old wooden spears from Schöningen suggest fire was used to harden tools as well.

The effects of fire are far-reaching. Cooked food is easier to digest, releasing the energy budget needed for a smaller gut and a larger brain. Fire offered protection from predators; it extended the active day into the night, and made possible the long evening gatherings in which language, story and shared memory could take shape. Much of the eventual adaptation to colder climates — and the spread into Eurasia — is unimaginable without it.