| A | B |
|---|
| Evolution | The theory that species change over time |
| Imprint | A type of fossil in which a film of carbon remains after the other elements of the organism has decayed |
| Mold | Impression of the track or shape of an organism |
| Cast | Sediment fills the crevises of an organism and creates a cast of its structure |
| Half-life | The amount of time radioactive material takes to decay |
| Geologic Time Scale | A scale that outlines history of life on earth |
| Homologous Structures | Structurs that are embrylogically similar |
| Vestigal Organs | seemingly functionless parts |
