15 : The Culmination Of Two Million Years Instant

For 99% of these two million years, progress was glacial. A hand-axe design might remain unchanged for a hundred millennia. However, the last 10,000 years triggered an exponential curve:

We stopped chasing food and began controlling it, leading to cities and civilizations. 15 : The Culmination of Two Million Years

By mastering fire, we "outsourced" our digestion, allowing more energy to fuel our growing brains. For 99% of these two million years, progress was glacial