A dive into the deep sea is like a trip to outer space. The descent into darkness reveals twinkling lights. Sunlight cannot penetrate to these depths. Instead, this light show comes from the animals that live here. Scientists call it bioluminescence—when living organisms create their own light using a chemical reaction.

Bioluminescence is relatively rare on land, where fireflies, glow worms, and fungi are the most familiar examples. But MBARI researchers have learned bioluminescence is common among deep-sea animals. About three-quarters of life in the water column can produce bioluminescence. The MBARI team is working to decipher the secret language of light in the ocean’s depths.