| A | B |
|---|
| fossil record | all fossils ever discovered on Earth |
| mold | impression of an organism in a rock |
| cast | fossil copy of an organism in a rock |
| trace fossil | preserved evidence of the activity of an organism |
| geologic time scale | chart that divides Earth's history |
| extinction | when all organisms of a species die |
| biological evolution | change over time in a population of related organisms |
| naturalist | person who studies plants and animals by observing them |
| variation | a slight difference in an inherited trait of individual members of a species |
| natural selection | process by which populations of organisms with variations that help them survive in their environments live longer, compete better, and reproduce more |
| adaptation | inherited trait that increases an organism's chance of surviving and reproducing |
| camouflage | adaptation that enables a species to blend in with its environment |
| mimicry | resemblance of one species to another species |
| selective breeding | breeding of organisms for desired characteristics |
