The only direct way we have of learning about dinosaurs is by studying fossils. Fossils are the remains of ancient animals and plants, the traces or impressions of living things from past geologic ages, or the traces of their activities. Fossils have been found on every continent on Earth, maybe even near where you live . Most fossils are excavated from sedimentary rock layers .
Sedimentary rock is rock that has formed from sediment, like sand, mud, small pieces of rocks.
Eventually, they are compressed into sedimentary rock. The layers that are farther down in the Earth are older than the top layers. A fossilized object has the same shape as the original object, but is chemically more like a rock. Paleontology is the branch of biology that studies the forms of life that existed in former geologic periods, chiefly by studying fossils. Fossils have the same shape that the original item had, but their color, density, and texture vary widely.