| A | B |
|---|
| Evolution | the theory that species change over time |
| Imprint | a type of fossil in which a film of carbon remains after the other elements of an organism have decayed |
| Mold | a type of fossil where an impression of a shape or track of an organism has survived |
| Cast | forms when sediments fill the cavity left by a fossil mold |
| Half-life | the period of time it takes for one-half of the radioactive material to decay |
| Homologous structures | structures that are embrologically similar but have different functions |
| Vestigial organs | seemingly function-less parts |
| Natural selection | the process where organisms with favorable variations survive and reproduce at a higher rate |
| Adaption | an inherited variation that increases an organism's chance of survival in a particular enviroment |
| Adaptive radiation | an evolutionary pattern where many related species evolved from a single ancestral species |
| Divergent evolution | the process of two or more related species becoming more and more similar |
| Convergent evolution | unrelated species becoming more and more similar in appearance as they adapt to the same kind of enviroment |
| Coevolution | the joint change of two or more species in close interaction |
