Control of Fire

The capability to maintain, transport, and eventually ignite fire on demand. It arrived in stages across hundreds of thousands of years: first tending wildfire embers, then carrying fire between camps, and finally starting it from nothing with friction or sparked stone. The ~1,000,000 BC date marks the earliest secure evidence of fire *use*; securely habitual control appears later, roughly 400,000–790,000 years ago.

Fire is the root node of nearly everything. Cooking effectively pre-digests food, unlocking enough calories to afford our enormous brains. Heat extended human range into cold climates, light extended the day, and flame became the first chemical laboratory — the path to pottery, charcoal, and every metal runs through it.

The first control was simply feeding a naturally-started fire; starting one from nothing came much later. The earliest reliable starting method was friction. A hardwood spindle spun rapidly against a softwood board grinds off hot dust that, past roughly 400 °C, coalesces into a glowing ember; the ember is dropped into dry tinder and coaxed with breath into flame. Percussion (flint against pyrite) came later and travels better in wet climates.

Cooking, warmth, and protection immediately; charcoal, pottery kilns, and all of metallurgy downstream. Almost every hard edge in this graph eventually traces back here.