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What are fossils and where did they come from? Fossils are the preserved, hardened remnants (leftovers) of animals and plants that existed long ago. Many people are interested in dinosaur fossils, because they no longer exist. Dinosaurs were inhabitants of Earth for about 200 million years, but they became extinct before humans existed. They left behind parts of their bones, such as skeleton and teeth. They also left footprints in the mud, which had hardened into rock. Dinosaur fossils are not the only type of fossil. Plants, shells, wood, clams, reptiles, and more organisms have left fossils, too. These fossils have been found all over the world!
There are two types of fossils that give scientists clues about prehistoric life through being preserved in soil: molds and casts. Molds are rocks that have formed from mud around the shape of a plant or animal that leaves an empty area called a mold. A cast is formed when minerals or mud fill in the inside of a structure and it is the same shape and size of the living organism.
The third type of fossil shows evidence of ancient life are animal bones. These bones are often preserved, or saved, in sedimentary rocks because they change into different rocks and maintain their inside contents.
Fossils can give people special information, such as an animal’s diet, size, and how they’ve adapted, Scientists who study fossils are called paleontologists.
Paleontologists study the history of life and continue to search for information by digging up fossils and studying them in their laboratories. As more plants and animals become extinct, future paleontologists will discover information about these creatures.