| A | B |
|---|
| population | group of individuals that belong to the same species, live in the same area, and breed with ohters in the group |
| natural selection | process by which populations change in response to their environment as individuals better addapted to the environment leave more offspring |
| adaptation | process of becoming adapted to an environment: an anatomical structure, physiological process, or behavioral trait that improves an organism's likelihood of survival and reproduction |
| microevolution | change that occurs within a species over time |
| isolation | condition in which two populations of a species are separated so that they cannot interbreed. |
| species | group of organisms that look alike and are capable of producing fertile offspring in nature |
| extinct | term used to indicate species that have disappeared permanently |
| macroevolution | change that occurs among species over time as new species evolve and old species become extinct |
| fossil | preserved or mineralized remains or traces of an organism that lived long ago |
| homologous structures | structures that share a common ancestry |
| paleontologist | scientist who studies fossils |
| vestigial structures | structure reduced in size and function;considered to be evidence of an organism's evolutionary past |
| divergence | accumulation of differences between groups; can lead to the formation of new species |
| speciation | process by which new species are formed |
