Engage Learning Magazine Geologic Timeline & Types of Fossils | Page 2

Depending on how a fossil forms, paleontologists sort and classify them. In a petrified fossil an organism’s tissue is replaced by minerals. A footprint is a trace fossil. 26 ENGAGE An organism trapped in amber, peat or tar is a preserved fossil. A silhouette of an organism is a carbon film. @engagelearningmag An organism that leaves an outline