OLogy Paleontology is packed with mysteries about living things such as plants and animals that lived thousands, millions, and billions of years before the first modern humans. To solve these mysteries, paleontologists use fossils. Fossils are the remains or traces of ancient life that are usually buried in rocks. Examples include bones, teeth, shells, leaf impressions, nests, and footprints. This evidence reveals what our planet was like long ago.
Fossils also show how animals changed over time and how they are related to one another.
While fossils reveal what ancient living things looked like, they keep us guessing about their color, sounds, and most of their behavior. Most ancient living things never became fossils. When they died, scavengers ate them, they decayed, or they were worn away by wind and water until they disappeared. Some were destroyed by Earth's heat and pressure. Luckily for us, some living things were preserved as fossils.