The theory of continental drift suggests that the positions of the continents have changed over time. Alfred Wegener proposed this theory in the early 20th century, and he collected diverse pieces of evidence to support his theory. Some of the key evidences of continental drift theory are:
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Geological fit: The coastlines of South America and West Africa seem to match up, and the terrains of separate continents conform as well.
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Fossil evidence: Scientists have found fossils of similar types of plants and animals in rocks of similar age on the shores of different continents. This suggests that the continents were once joined.
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Glacial evidence: Indications of widespread glaciation from 380 to 250 million years ago are evident in Antarctica, southern South America, southern Africa, Madagascar, India, and Australia. These areas were once part of a single landmass.
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Paleomagnetic evidence: Rocks on either side of a mid-ocean ridge show a symmetrical pattern of magnetic polarity reversals. This indicates that the rocks were formed at the same time and have moved away from each other.
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Seafloor spreading: The age of the seafloor increases with distance from the mid-ocean ridge, indicating that new seafloor is being created at the ridge and moving away from it.
These evidences, along with others, led to the development of the theory of plate tectonics, which explains how the Earths lithosphere is divided into plates that move and interact with each other.
