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Continental Drift 1

#1: Fact or Fiction?

In 1912, when the German Meteorologist and Geophysicist, Alfred Wegener first proposed that the continents had started off as one huge land mass, that drifted apart, most people thought he was crazy. In fact he was almost correct, although he had it just a little bit wrong.

The Proposal

Wegener was the first scientist to publish a scientific paper stating that the world had originally had only one continent. He wasn't the first person to think like this, just the first one who was brave enough to announce it to the world. Several people had noticed that the continents could fit together like pieces of a jigsaw puzzle. This was particularly noticeable with the West coast of Africa and the East coast of South America. If you could remove the 4,000 miles of ocean that lay between them they would fit together perfectly. There were other things that pointed to the fact they had once been joined.

Mountain ridges on one continent could be matched to mountain ridges on the other. The mountains had the same structure and the same type of rocks. When you fit the two continents together, the ends of the mountain ranges lined up.

They also knew that fossils belonging to the same animals and plants could be found on different continents, separated by thousands of miles of ocean.

Wegener, being a meteorologist, also noticed that fossils found in some areas could not possibly have survived the climatic conditions there. For instance, some of the fossils found on Antarctica, could never have survived the cold conditions there. Those animals and plants must have originally been much nearer the equator.

What Wegener proposed was that the continents had once belonged to a single landmass, which he called Pangaea. He then said that something had caused them to split apart and drift through the oceans, until they came to rest in the positions we know.

The Reaction

The scientific community was perfectly willing to believe that the continents had once been joined together, but they were not willing to believe that they had drifted through the ocean. After all, everyone knows they go right down to the earth's crust, so in order for them to drift, they must have somehow floated on or through the crust.

Instead, they preferred the theory that somehow the ocean floor kept rising and falling, causing it to reach above sea level at times, forming bridges of land. The animals could walk across these bridges from continent to continent. The theory was that the continents hadn't moved, but that the land joining them had long since sunk below the oceans. This preferred theory wasn't very believable either. It didn't explain why the continents could fit together like a jigsaw, or why mountain ranges stopped on one side of the ocean only to start again on the other side.

Further Investigations and Discoveries

By the time Wegener died in 1930, most scientists still refused to believe his Pangaea theory. Following the two world wars, and the advances in underwater technology that came with them, some important discoveries were made. These underwater investigations and their discoveries proved that Wegener had gotten the theory more than half right. The answer to how the continents had moved could be found beneath the waves on the ocean floor.

Conclusion

It is now an accepted fact that the continents once began as a single landmass that slowly separated and became the continents that we know today. In fact, most people today think that it is fairly incredible that just 40 years ago scientists thought this idea was crazy.

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