Paleontology is the study of plants and animals that lived millions of years ago. The history of life on earth is revealed by fossils, the rare remains of ancient organisms found in rocks worldwide.  Detailed graphics, diagrams and video images help us understand the fossil record, how fossils are formed, the six time periods of the Paleozoic Era, possible causes of the Permian Extinction, the formation of Pangea, the three time periods, plants and animals of the Mesozoic Era and the Cenozoic Era, extinction of the dinosaurs, the formation of the Great Lakes and the Rocky Mountains, and early humans in the Neogene Period,