A small marine amphipod has recently been discovered that carries another organism on its back. The "backpack" organism tastes bad. If a fish ingests the pair, it immediately spits them back out. If the amphipod is alone, however, it is readily eaten and swallowed. There is no apparent benefit in this relationship for the "backpack" organism, which appears to be neither helped nor harmed. This is therefore a case of

Question

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The relationship between the amphipod and the organism on its back is an example of commensalism because the backpack organism is neither helped nor harmed by the amphipod's presence, while the amphipod benefits from being unpalatable to predators when it carries the backpack organism.

A Small Marine Amphipod Has Recently Been Discovered That Carries