Alfred Wegener came up with the idea in 1912 that continent are slowly drifting around the earth. However, at first his theory was rejected.
Wegener noticed that the continents looked as though they might fit together like puzzle pieces (he would later name the original supercontinent Pangea). He also noticed that there were matching geologic features and rocks on different continents, as well as matching fossils of land animals. These animals could not have migrated across the ocean.
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