Be an eyewitness to the secret watery world that covers much of our planet and the incredible creatures that live in its depths.

THE EARTH, WITH ITS VAST EXPANSES of ocean, has not always looked the way it does today. Over millions of years the land masses have drifted across the face of the earth as new oceans opened up and old oceans have disappeared. Today's oceans only started to take shape in the last 200 million years of the earth's 4,500-million-year existence. But water in the form of vapour was present in the atmosphere of the early earth. As the earth cooled, water vapour condensed making storm clouds from which rain fell and eventually filled the oceans. As the oceans themselves changed, so too did life within the oceans. Simple organisms first appeared in the oceans 3,300 million years ago and were followed by more and more complex life forms. Some forms of life became extinct, but others still survive in the ocean today, more or less unchanged.

Oceans of the past

  Oceans today

Life in the oceans

Waves and weather

Sandy and muddy

Soft sea bed

Rocks underwater

On the rocks

The coral kingdom

Life on a coral reef

  Sea meadows

Predators and prey

Homes and hiding

Attack and defence

The jet set

  Moving along

 Ocean travellers

The twilight zone

The darkest depths

  On the bottom

 Vents and smokers

Diverse divers

Underwater machines

Ocean explorers

Wrecks on the sea bed

Harvesting fish

Ocean products

Oil and gas exploration

Oceans in peril

Did you know?

 The world's oceans

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  Glossary

   Index