| A | B |
|---|
| Darwin | Used observations from Galapagos Islands to describe change over time |
| theory | well-tested explanation for observations or experimental results |
| evolution | Biological change over time & process of descent with modification |
| gene | sequence of DNA that codes for a specific trait |
| homologous structures | structures that are similar in different organisms from common ancestor |
| adaptation | inherited behavior or structure that helps an organism survive & be fit |
| trait | a specific characteristic that an organism can pass to offspring by genes |
| natural selection | process by which organisms best adapted to environment survive/are fit |
| artificial selection | When humans choose to breed organisms with desired traits |
| variation | Differences within a species-helps species survive into the future |
| biodiversity | Total number of extant species on Earth |
| extinction | a species that has died out & has no living members |
| endangered species | A species in danger of becoming extinct in the near future |
| threatened species | A species that could become endangered in the next few years |
| descent with modification | species changing and forming over time due to isolation & mutations |
| vestigial organs | inherited body parts that are no longer necessary |
| isolation | geographic separation of members of a breeding population or species |
| environmental change | changes (fast or slow) in the physical world |
| gradualism | periods of slow, steady change (biologically or environmentally) |
| punctuated equilibrium | periods of rapid, massive change (biologically or environmentally) |
| fossil | Preserved remains or traces of a long-dead organism |
| competition | struggle among organisms for food, water, shelter, space & mates |
| niche | how and where an organism lives an interacts with its environment |
| speciation | new species formed due to isolation, mutations & environmental change |
| habitat | Place that allows an organism to live & get resources |
| Galapagos Islands | Site of many of the observations leading to Darwin’s evolution theory |
| theory of evolution | explanation of descent from a common ancestor with modifications |
| species | organisms so similar that can reproduce & have fertile offspring |
| population | members of the same species living in the same area |
| extant | opposite of extinct; still alive |
