| A | B |
|---|
| species | a group of organisms with members that reproduce among themselves intheir natural environment |
| evolution | changes in the hereditary features of a species over time |
| natural selection | organisms with traits best suited to their environment are more likely to survive and reproduce |
| variation | an inherited trait that makes an individiual different from other members of the same species |
| adaptation | any adaptation that makes an organism better suited to its environment |
| gradualism | the model that describes evolution as a slow change of one species to another, new species |
| punctuated equilibrium | rapid evolution can come about by the mutation of just a few genes, resulting in the appearance of a new species |
| Lamarck | believed that organisms evolved by "acquired characteristics" |
| Darwin | believed that organisms evolve through natural selection |
| Homologous Structures | body parts that are similar in origin and structure |
| Vestigial Structures | Remnants of structures that were functional in ancestral forms, but in modern forms are smaller and serve no function. |
| embryology | the study of development in organisms |
| DNA | the molecule that controls heredity |
| sedimentary rock | a rock type formed from particles of preexisting rocks |
| relative dating | determining the age of a fossil using its location in the earth |
| radiometric dating | determining the age of a fossil using radioactive elements within the fossil |
| radioactive element | gives off radiation due to an unstable nucleus |
