As illustrated in the movie Finding Nemo, clownfish and sea anemones have a mutual symbiotic relationship. The latter Wikipedia article states that “The territorial [clown] fish protects the anemone from anemone-eating fish, and in turn the stinging tentacles of the anemone protect the clownfish from its predators. A special mucus on the clownfish protects it from the stinging tentacles”. Of course, as also demonstrated in Nemo, mutualism breaks down when uninvited barracudas join the party

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