The fossil of Mesosaurus proves the hypothesis of "continental drift". This can be defined as the gradual movement of continents across earth's surface by the movement of tectonic plates. This fossil is an example of the other fossils that are found on separate continents and no where else, this suggests that the continents were once joined. The distance between South America and Africa is not less, it is physiologically not possible for Mesosaurus to swim between two continents. This proves that once the continents were joined and as a result of continental drift they are separated.