| A | B |
|---|
| adaptations | changes to a species that happen over a long time that help organisms to cope with their environmental pressures |
| natural selection | process by which organisms with beneficial traits survive and reproduce at a greater rate than those less suited to that environment |
| offspring | young, children, babies, progeny, descendents |
| ancestors | those from whom one is descended; forebears, parents, grandparents, etc. |
| behavioral adaptation | an action that helps the organism survive; includes how an organism gets food, how it escapes predators, etc. |
| Charles Darwin | scientist who studied nature and wrote the theory of natural selection |
| structural adaptation | a physical characteristic that helps the organism survive; includes camouflage, claws, sharp teeth, etc. |
| survival of the fittest | process of struggling to survive against environmental pressures |
| environmental pressures | aspects of the environment that make it hard for some organisms to survive; includes predators, weather conditions, limited resources, etc. |
| extinction | the process of a species dying out completely |
| overproduction | a species has more offspring than will survive to maturity |
| genetic variation | the individuals within a species are all genetically slightly different from each other |
| ectothermic (cold-blooded) | animals that depend on their environment for heat |
| endothermic (warm-blooded) | animals that make their own heat using energy from food |
| vertebrates | animals with backbones |
| invertebrates | animals without backbones |
