Updated 24 March 2020
Fossils are the preserved remains, impressions, or traces of any once-living thing. There are many different ways fossils can form, and examples of fossils include, but are not limited to, bones, shells, exoskeletons, imprints, and organisms preserved in amber.
Usually, paleontologists consider a specimen true fossil if it is more than 10,000 years old. The oldest fossils in the fossil record, a term used by paleontologists to describe all the fossils ever found and any information learned from them, are about 3.48 billion years old.