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Zones of the Open Ocean

Oceanographers divide the ocean into three broad zones, each with different species.
(Smithsonian Institution)

Oceanographers divide the ocean into three broad zones. Together, they could hide 20 Washington Monuments stacked on top of each other. Each zone has a different mix of species adapted to its light levels, pressures, and temperatures. About three-fourths of the ocean is deep, permanently dark, and cold. Learn more about these different zones.