| A | B |
|---|
| species | a group of similar organisms that can mate with each other and produce fertile offspring |
| adaptation | a trait that helps an organism survive and reproduce |
| scientific theory | a well-tested concept that explains a wide range of observations |
| evolution | gradual change in a species over time |
| natural selection | the process by which individuals that are better adapted to their environment are morel ikely to survive and reproduce than other members of the same species |
| variation | any difference between individuals of the same species |
