| A | B |
|---|
| competition | the contest among organisms for the limited resources of an ecosystem |
| symbiosis | a long term relationship between different kinds of organisms |
| instinct | a behavior that an organism inherits |
| learned behavior | a behavior an organism learns from its parents |
| mutualism | a relationship where both organisms benefit |
| exotic | an imported or nonnative organism |
| extinct | no longer in existence |
| endangered | a population of organisms that is likely to become extinct if steps are not taken to save it |
| threatened | a population of organisms that is likely to become endangered if it is not protected |
