Continental Drift

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Continental Drift
And
Plate Tectonics

The evidence which gave rise to the theory of continental drift -- more correctly called plate tectonics -- includes the following:
· The coasts of the continents surrounding the Atlantic Ocean could fit together like a jigsaw puzzle.
· Living animals in widely separated lands are similar.
· Fossil plants and animals in India, South Africa, Australia, Antarctica and South America are similar to each other and different from plants and animals found in other parts of the world at the same time.
· There are numerous geological similarities between eastern South America and western Africa.
· Paleomagnetism tells us how far from the poles rocks were when they formed, by looking at the angle of their magnetic field. Apparent contradictions can only be explained if we assume the continents have moved over time.

In 1620, Francis Bacon noted that the west coast of Africa and the east coast of South America looked as if they would fit together. In 1912, Alfred Wegener published a theory to explain why the Earth looked like a huge jigsaw.
He suggested that a very long time ago all the land that covered the Earth had been joined together into one huge continent. He suggested that millions of years ago, a supercontinent, which he named Pangaea, had somehow broken up. The different parts had then drifted into the present day positions.
His evidence for this was drawn for several sources, covering geology, biology, geography and other sciences.
He was able to show that fossils of a small reptile called Mesosaurus were found only in South Africa and Brazil. The chance of this reptile crossing the ocean was very small and, even if it did, why did it stop in these two places? To Wegener it seemed that the only sensible explanation was that South Africa and Brazil had been joined together at the time when Mesosaurus lived.

He also noted that the rocks in South Africa and southeas...