Wegener?s first idea was that the continents fit like a giant jigsaw puzzle. He noticed similar characteristics along the coastline of the South Atlantic. Scientists challenged this idea and said that the shorelines were modified by erosional processes. The best example of this idea by Wegener could be looked at South America and Africa. It looks as if South America could just slide right into place with Africa. Some overlap is present but that is due to streams depositing sediment along the coasts.
Wegener also found that fossils match across seas. He found that the same fossil organisms were found in rocks from both South America and Africa and began to look further into this idea. Wegener found that most paleontologists agreed that some land connection was needed to explain how identical fossils were found across different continents. One example of this thought was the fossil of Mesosaurus. Fossils were found in South America and Africa but nowhere else. If Mesosaurus could travel from continent to continent then the fossil should be found in other continents.
Another thought that backed up Wegener was the thought that rock types and structures match. He believed that if the continents were once together then the rocks found in a certain region in one continent should line up to a certain region in