The Island With No Predators

Two islands. One difference.

Both islands start with the same grass and the same 90 grazers, all equally fast. Only the left island has predators.

Nothing is scripted. Every baby inherits its parent's top speed with a tiny random change, and the island decides who survives.

• Grazers. Colour shows top speed: blue is slower, yellow is like their ancestors, red is faster.
• Predators. They hunt grazers. Faster grazers get away more often.
• Grass. Green is lush, sandy is eaten. It grows back slowly.