Alfred Wegener did not discover the theory of plate tectonics. He is credited with proposing the theory of continental drift, which was a precursor to plate tectonics.

Here's the breakdown:

* Alfred Wegener (1912): Proposed the theory of continental drift, suggesting that the continents were once joined together in a supercontinent called Pangaea and have since drifted apart. He provided evidence like the fit of the continents, fossil distribution, and geological similarities between continents.

* Plate Tectonics (1960s): The theory of plate tectonics developed later, building upon Wegener's work. It explains the movement of Earth's lithosphere (the rigid outer layer) through the interaction of tectonic plates.

So, while Wegener's work was crucial in laying the foundation, the theory of plate tectonics is a more comprehensive model that emerged in the 1960s.