Animals
How Bioluminescence Works in Animals: The Chemistry of Living Light
More than 76% of deep-sea animals produce their own light. Fireflies flash in coordinated sequences. A jellyfish discovered off the coast of Friday Harbor, Washington, gave biologists a tool that transformed cell biology, earned three scientists a Nobel Prize, and now glows inside cancer cells in laboratories around the world. Bioluminescence — light produced by a living organism — is one of evolution's most useful accidents, and its chemistry is surprisingly simple.