Africa       Antarctica       Asia       Australia
Europe       North America       South America
The earth's surface, or the crust, is always changing very slowly. About 275 million years ago, the world map looked very different. All the land was joined together in one supercontinent which scientists call Pangaea.
About 180 million years ago, Pangaea began to break up into pieces, pulled apart by the moving plates of the crust. As these plates have shifted, they have pushed up great mountain ranges and created deep valleys. As volcanoes have erupted, new mountains and islands have formed.
About 65 million years ago, the continents began to look more as they do today. Australia, Antarctica and South America had drifted away from Africa. As North America began to break away from Eurasia, the rift in the North Atlantic grew. A plate bearing India was moving toward Asia, and eventually collided, creating the Himalayas.
Today's map shows that all the continents that once made up Pangaea are now separated by great bodies of water. Today, there are seven major continents: North America, South America, Australia, Europe, Asia, Africa and Antarctica. There are four major oceans: Atlantic, Pacific, Indian and Arctic.