What is the theory of plate tectonics?
Plate tectonics is the theory that Earth’s outer layer is made up of plates, which have moved throughout Earth’s history. The theory delves into how and why mountains, volcanoes, earthquakes and other events moved continents that are now widely spread, and how animal life was dispersed accordingly. You can find more information here: http://www.pbs.org/wgbh/aso/tryit/tecton…
