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LET'S EXPLORE The living world

What lives in the oceans?

Animals living in shallow coastal watersAnimals living in shallow coastal watersMore than two-thirds of the Earth’s surface is covered by the oceans. The oceans are home to a wide variety of life, from microscopic plants to giant whales. Most ocean creatures, however, live in shallow waters near the coast, particularly on the sea bed. In the rest of the ocean, especially below a depth of about 1000 metres (3300 feet) where it is always cold and dark, there are very few living things to be found.

The sunlit surface waters of the oceanThe sunlit surface waters of the ocean

Surface waters

The richest variety of life in the oceans is found near the water’s surface. Here, sunlight allows microscopic plants, called plankton, to live. The plankton float in surface waters. They are eaten by tiny animals, another kind of plankton, that drift in the ocean currents. These include fish larvae (baby fish that have just hatched out). Fish and squid feed on them.

Only the living surface of coral is coloured—the layers of dead skeletons underneath are white. The living layer of tiny coral polyps feed on plankton that drift by in the current.

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