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Today many scientists use a six-kingdom system for classifying living things. In the past, scientists recognized only two kingdoms, plant and animal. Even today, not all scientists agree on how many kingdoms there should be. Why do you think classification changes? What tools coulf have helped increase the number of kingdoms in the past? Do you think the classification groups could change again? Why or why not?
Possible Answer: Classification changes as new discoveries are made about exsisting organisms or as new organisms are identified. The microscope is one tool that probably changed the way scientists classified organisms. Classification could probably change again as new information is found.