| A | B |
|---|
| Trait | A distinguishing quality that can be passed from one generation to another. |
| Selective Breeding | The breeding of organisms that have certain desired traits. |
| Natural Selection | The process by which organisms with favorable traits survive and reproduce at a higher rate than other organisms without favorable traits. |
| Mutation | A change in the order of bases in an organism's DNA; deletion, insertion, or substitution. |
| Generation Time | The period of time between the birth of one generation and the birth of the next generation. |
| Speciation | The process by which two populations of the same species become so different that they can no longer interbreed. |
| Adaptation | A characteristic that helps an organism survive inits environment. |
| Species | A group of organisms that can mate with one another and produce fertile offspring; the most specific of the seven levels of classification. |
| Evolution | The process by which populations accumulate inherited changes over time; change over time. |
| Fossil | The solidified remains or imprints of a once-living organism. |
| Fossil Record | A historical sequence of life indicated by fossils found in layers of the Earth's crust. |
| Vestigial Structure | The remnant of a once-useful anatomical structure. |
