Drifting Continents Did Pangea Exist The Theory of

Drifting Continents Did Pangea Exist?

The Theory of Continental Drift • In 1912, a German scientist named Alfred Wegener proposed that at one time the continents were joined together as one landmass, but over time they have drifted slowly to their current location. • His hypothesis is called the continental drift theory.

Pangaea • Greek for "all earth. " • “Supercontinent” that existed over 250 million years ago. • The name was given to all of the present continents that were once joined in a single landmass.

• Wegener’s first piece of evidence was that he noticed that the continents fit together like a puzzle.

Evidence from Landforms • Mountain ranges in South Africa line up with mountain ranges in Argentina, South America. • Mountain ranges in North America also match up with mountain ranges in Africa and Europe.

• European coal fields (rock similarities) match up with similar fields in North America

Evidence from Fossils • A fossil is any trace of an ancient organism that has been preserved in rock. • Glossopteris fossils have been found in rocks in Africa, South America, Australia, India, and Antarctica. • Fossils of the animals Mesosaurus and Lystrosaurus have been found in places now separated by oceans.

Evidence from Climate • Fossils of tropical plants have been found too far south to have survived. • Glacier markings on rocks showed evidence that the continents were further South where it was colder and glaciers could survive.

Rejection!! • Even with the evidence, most scientists rejected Alfred Wegener’s theory for about a half a century, because he couldn’t explain how the continents drifted apart.