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Biology

Bioluminescent Communication and Counterillumination in Deep-Sea Fishes

Quick fact

Many deep-sea fish can adjust the intensity and color of their bioluminescence to exactly match the faint blue light filtering down from the surface, effectively erasing their silhouette from predators looking upward.

Why this is interesting

Imagine being in a world with no sunlight, where the only light comes from living creatures. For deep-sea fish, producing your own light isn't just a trick—it's a way to talk, find food, and even hide.