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symbiosis
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A clown anemonefish, Amphiprion percula, with bright orange and white stripes, swims among the pale tentacles of a sea anemone in Tulamben, Bali, Indonesia.
Examine commensalism among fish species such as shrimp, the neon goby, and moray eels
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Lynn Margulis
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Endosymbiosis
lichen
interspecific association
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Biology LibreTexts - Symbiosis (Oct. 28, 2026)
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A clown anemonefish, Amphiprion percula, with bright orange and white stripes, swims among the pale tentacles of a sea anemone in Tulamben, Bali, Indonesia.
symbiosis Clownfish (Amphiprion) amid sea anemones (Heteractis magnifica), Great Barrier Reef, Australia. The two species protect each other from predators in mutual symbiosis.

symbiosis

biology
Also known as: symbiont
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Encyclopaedia Britannica's editors oversee subject areas in which they have extensive knowledge, whether from years of experience gained by working on that content or via study for an advanced degree....
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symbiosis, any of several living arrangements between members of two different species, including mutualism, commensalism, and parasitism. Both positive (beneficial) and negative (unfavourable to harmful) associations are therefore included, and the members are called symbionts.

Any association between two species populations that live together is symbiotic, whether the species benefit, harm, or have no effect on one another.

The Editors of Encyclopaedia Britannica This article was most recently revised and updated by Adam Augustyn.