What is the primary evidence supporting the theory of plate tectonics?

The primary evidence supporting the theory of plate tectonics stems from the fit of continental coastlines and fossil evidence. This observation highlights how continents, particularly South America and Africa, appear to fit together like pieces of a puzzle, suggesting they were once joined.

Additionally, fossil evidence found on different continents supports this idea, showing that similar species existed on land masses that are now widely separated by oceans. For instance, fossils of the Mesosaurus, a freshwater reptile, have been discovered in both South America and Africa, indicating that these continents were once connected, allowing the species to inhabit both regions.

This convergence of geological shape and paleontological data coherently illustrates the movement of tectonic plates. It forms a compelling argument for continental drift as a key component of plate tectonics, reinforcing the connection between the movement of Earth's plates and the distribution of continents and life forms across the globe.