Why do we rarely see food chains with quinary (5th level) consumers?

Energy is passed up a food chain or web from lower to higher trophic levels. This loss of energy explains why there are rarely more than four trophic levels in a food chain or web. Sometimes there may be a fifth trophic level, but usually there's not enough energy left to support any additional levels.

Explanation: :) Hope it helps

well, that's easy; the answer's c, "it reduces contamination of the water and substrate of the estuary."

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explanation:

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