1. adaptation - inherited characteristic that increases an organism's chance of survival.
2. artificial selection - selection by humans for breeding of useful traits from the natural variation among different organisms.
3. common descent - principle that all living things were derived from common ancestors.
4. descent with modification - principle that each living species has descended, with changes, from other species over time.
5. evolution - change in a kind of organism over time; process by which modern organisms have descended from ancient organisms.
6. fitness - ability of an organism to survive and reproduce in its environment.
7. fossil - preserved remains or evidence of an ancient organism.
8. homologous structures - structures that have different mature forms in different organisms but develop from the same embryonic tissues.
9. natural selection - survival of the fittest - process by which individuals that are better suited to their environment survive and reproduce most successfully.
10. struggle for existence - competition among members of a species for food, living space, and the other necessities of life.
11. theory - well-tested explanation that unifies a broad range of observations.
12. vestigial organ - organ that serves no useful function in an organism.
2. artificial selection - selection by humans for breeding of useful traits from the natural variation among different organisms.
3. common descent - principle that all living things were derived from common ancestors.
4. descent with modification - principle that each living species has descended, with changes, from other species over time.
5. evolution - change in a kind of organism over time; process by which modern organisms have descended from ancient organisms.
6. fitness - ability of an organism to survive and reproduce in its environment.
7. fossil - preserved remains or evidence of an ancient organism.
8. homologous structures - structures that have different mature forms in different organisms but develop from the same embryonic tissues.
9. natural selection - survival of the fittest - process by which individuals that are better suited to their environment survive and reproduce most successfully.
10. struggle for existence - competition among members of a species for food, living space, and the other necessities of life.
11. theory - well-tested explanation that unifies a broad range of observations.
12. vestigial organ - organ that serves no useful function in an organism.