Earth History

5. traits that help organisms survive in a given environment
6. older layers of rock lie under younger rock layers
11. age of an object or event compared to another object or event
14. Earth's rigid outer shell
15. Selection, process of which organisms are best suited to a particular environment
16. organisms so similar that they are able to mate and produce fertile offspring
17. lithosphere broken up into sections

1. body part that does not see to play a role in body functions
2. body parts that have similar function but not similar structure
3. Fossil, fossil of an organism that existed for a short period of time
4. actual age of a rock or fossil
7. body parts of different organisms that have similar structure but not similar function
8. long chains of underwater mountains
9. two oceanic plates move apart to form new oceanic crust
10. branch of life science that names and groups organisms
12. no more of a species living on Earth
13. cylinder of ice removed from an ice sheet
18. process by which species change over time