How do fish sleep?: Quick Facts

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The Information Architects of Encyclopaedia Britannica

Last updated

Oct. 26, 2026

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A variety of brightly colored tropical fish swim among coral formations in the clear water of a Belizean Caribbean reef.

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Topics

fish Why Is Sleep Important?How do fish reproduce?How Much Sleep Do You Need?Does Eating Turkey Make You Sleepy?Do fish drink water?Do snakes sleep?How do fish breathe?Why do bats sleep upside down?Do whales sleep?Why are fish high in mercury?