Dinosaurs lived on earth for 160 millons years ago. Suddenly all the Dinosaurs extinct 65 millons years ago. The bodies of some Dinosaurs were covered by sand and dirt, after they were extinct. The bones were hidden for millon's of years, water and minerals seep through the sand and slowly turned the bones into stones. Heavy wind and rain wash away part of the sand and dirt. Then part of the dinosaur can be seen. A scientist than finds the fossil of a Dinosaur and carefully, digs it out of the stone to take to a museum and study.
