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Symbiosis: Mutualism, Commensalism, and Parasitism

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State

Symbiosis is a close, long-term relationship between two species: mutualism when both benefit, commensalism when one benefits and the other is unaffected, parasitism when one benefits at the other's expense.

Show

A tapeworm consuming a host's nutrients is parasitism; a bird nesting harmlessly in a tree is commensalism.

Watch for

Symbiosis names any close relationship — it does not specify which outcome applies.