What is a fossil?

Fossils are the remains, relics or remains of paleontology preserved in paleostrata. Fossils can be divided into four categories: solid fossils, trace fossils, die-casting fossils and molecular fossils. Generally speaking, the biological boundary was ten thousand years ago. The creatures 10,000 years ago were paleontology, and those 10,000 years later were living creatures. Due to natural disasters, such as volcanic eruptions, mudslides and other natural disasters, they were buried instantly and isolated for oxidation.

The remains, relics or biological traces of animals or plants belonging to paleogeological times preserved in the earth's crust are called fossils.

In the long geological age, countless creatures lived on the earth, and many of their dead bodies or traces left by life were buried by the sediment at that time.

In the following years, the organic matter in these biological remains was completely decomposed, and the hard parts, such as shells, bones, branches and leaves, together with the surrounding sediments, were petrified into stones, but their original forms and structures (even some subtle internal structures) still existed; Similarly, the traces left by those creatures when they are alive can be preserved in this way.

Reference: Baidu Encyclopedia-Fossil Web page link