| A | B |
|---|
| evolution | change in a kind of organism over time |
| theory | well-tested explanation that unifies a broad range of observation |
| fossil | preserved remains is evidence of an ancient organism |
| artificial selection | selection by humans for breeding of useful traits from the natural variation among different organsism |
| struggle for existence | competition among members of a species for food, living space, and the other neccessities of life |
| fitness | ability of an organsism to survive and reproduce in its enviroment |
| adaptation | inherited characteristics that increse an organism's chance of survival |
| survival of the fittest | process by which individuals that are better suited to their environment survive and reproduce most sucessfully - also called natural selection |
| natural selection | process by which individuals that are better suited to their to their envirment survive and reproduce most successfully |
| descent with modification | principles that each living species has descended, with changes,from other species over time |
| common descent | principles that all living things were derived from common ancestors |
| homologous structure | structures that have different mature forms in diffrent organsisms |
| vestigial organ | organs that serve no purpose in the body of an organsism |
