Fireflies Make Light Through a Chemical Reaction Involving Luciferin

Green fluorescent protein, first isolated from the jellyfish Aequorea victoria, became a key tool for tracking molecules in living cells.

Single-celled dinoflagellates flash blue when disturbed, which makes breaking waves and swimmers' movements glow at night.

In the open ocean's deep waters, bioluminescence is so common that a majority of animals are thought to produce light.

Deep-sea anglerfish carry a light-producing lure, and its glow comes from symbiotic bacteria living inside it.