Survey
* Your assessment is very important for improving the workof artificial intelligence, which forms the content of this project
Download FOSSILS
Transcript
Earth Science Grade 8 Animal Dies Scavengers eat most of the flesh Bacteria eats away at the rest Sediments cover the remains Groundwater starts to filter through Rock is deposited into the bones one cell at a time. A fossil is made! Eat away the flesh Change to sediments Eats the rest Cover the remains (groundwater) passes through Replaces the bone cells • Once living material or traces of living material that has become preserved in rock • Minerals fill in the space held by the original substance • Examples: trees, bones, shells • When leaves or soft bodies materials buried • Examples: film of carbon left behind • Hole left behind when groundwater dissolves a shell or bone Cast • When minerals fill in the mold • Fossils that show how the organism lived • Examples: footprints, tail marks, eggs, nests, burrows Borrows Nest of Eggs • Used to show specific units of time • The best index fossils lived for a short period, but were wide spread
