For several million years, Earth swung between deep freezes and brief warm periods. Ice ages lasted almost 100,000 years at a time - shaping landscapes, species, and human evolution ❄️ Then, just 12,000 years ago, the ice began to melt. The world warmed, rainfall increased, and climates became more stable than they had been in a hundred thousand years. This warm window is the one we still live in today. Follow for more about the history of earth, the universe and humanity #BigHistory #STEMEducat