Flight takes more than wings. We need the right kind of air, the perfect materials cooked up over billions of years, and cosmic forces that are just right for us to leave the ground without tumbling off into space. Big History reveals how planet Earth is the perfect planet for flight.

Behind that cup of coffee or tea is a global story that goes back to the collision that created the Moon and the evolution of plant and animal life. The key is the molecule that gives your morning cup its kick: caffeine, the most popular drug in history. This is the story of how a plant poison became our drug of choice, and stimulated revolutions around the planet.