| A | B |
|---|
| fossils | the remains of plants or animals that lives in a previous geologic time |
| paleontology | the study of fossils |
| fossilization | the ways in which fossils are formed |
| mummification | when plants or animals die in very dry conditions, before they can decay. |
| freezing | when low temperatures in frozen soil and ice preserve organisms |
| amber | hardened tree sap |
| petrification | when minerals replace the organic materials in an organism |
| trace fossils | fossilized evidence of past animal movement like tracks or footprints |
| index fossils | fossils that occur only in rock layers of a particular geologic age |
| imprints | carbonized imprints of leaves stems flowers and fish. |
| molds and casts | When remains decay and leave an empty space |
| coprolites | fossilized dung or waste materials |
| gastroliths | fossilized stones from dinosaur stomachs. |
