The sea bed, or benthic zone, is inhabited by animals and plants that either live permanently on, burrow within, or are closely associated with the bottom of the ocean. Species found here are dictated more by the substrate - rock, sand, mud or coral, for example - than by the depth of water overhead. Many are specially adapted to living on the substrate and some to high pressure as the continental shelves gives way to the abyssal plains in deeper waters.

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