Bioluminescing Dinoflagellate

A photograph of a bright blue-speckeled dinoflagellate bioluminescing at night.
E. Widder, ORCA,

Sunset? Time to glow! A biological clock triggers bioluminescence in the dinoflagellate Pyrocystis fusiformis. At dusk, cells produce the chemicals responsible for its light. Hear from marine scientists about what it's like to encounter bioluminescent animals in the deep sea