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Earth History & Evol
| Term | Definition |
|---|---|
| Fossil | The preserved remains/traces of an organism that lived in the past. |
| Relative Age | "older" or "younger" comparing ages |
| Absolute Age | The number of years since the rock was formed. |
| Uniformitarianism | The slow change of Earth over time. |
| Continental Drift | States that all continents used to be a part of a huge landmass, but broke apart and drifted to other locations. |
| Pangaea | A supercontinent that existed during the late Paleozoic and early Mesozoic eras. |
| Extinct | No longer existing. |
| Unconformity | A buried surface separating two rocks of different ages. |
| Law of Superposition | "in a series of stratified sedimentary rocks the lowest stratum is the oldest" |
| Index Fossil | A fossil that is useful for dating and correlating the strata in which it is found. |
| Natural Selection | Organisms better adapted to their environment will live longer. |
| Evolution | The process of a species adapting/diversifying over time. |
| Adaptation | A change or the process of change by which an organism or species becomes better suited to its environment. |
| Anatomy | The bodily structure of an organism. |
| Intrusion | The action or process of forcing a body of igneous rock between or through existing formations, without reaching the surface. |
| Unconformity | A surface of contact between two groups of unconformable strata. |
| Mechanical Weathering | The process of breaking big rocks into little ones. |
| Chemical Weathering | The process of breaking rocks due to a chemical reaction. |
| Variation | A different or distinct form or version of something. |
| Geologic Time Scale | A system of chronological dating that relates geological stratigraphy (the study of the Earth's layers) to time. |
| Radioactive Decay | The process by which an unstable atomic nucleus loses energy. |