The Cleanup Crew

The next day, Polly flew high with the vultures. They went up in slow circles on the warm air. Her small green body looked funny next to their huge wings, but they made room for her. Her round glasses flashed in the sun.

Vultures are the news service of the Serengeti. Each bird can see a meal from kilometres away. But the real trick is this: they also watch each other. When one bird goes down, the others see it and follow. News travels across the whole plain without a sound.

The smallest workers are in the grass. Dung beetles roll balls of dung much heavier than their own bodies. At night, a beetle climbs on top of its ball and looks at the Milky Way. The stars show it how to roll in a straight line. Scientists proved this.

By evening Polly understood. Nothing on this plain is wasted. Everything has a job. The grass feeds the herds. The herds feed the hunters. Everything left feeds someone smaller. Polly flew home slowly, in no hurry at all.