Across
- 3. hollow area in sediment in the shape of an organism
- 5. trait that increases an organism's ability to survive
- 7. lava that hardens on the surface and forms igneous rock
- 8. preserved remains or traces of living things
- 9. well tested concept that explains a wide range of observations from the evidence collected
- 11. solid copy of the shape of an organism
- 13. any difference between individuals of the same species
- 15. scientist who studies fossils
- 18. change in living things over time
- 19. age of the rock compared to other rocks
Down
- 1. gap in the geological record
- 2. type of fossil in which mimerals replace all or part on the organism
- 4. no longer exists
- 6. process by which individuals that are better adapted to their environment are more likely to survive and reproduce
- 10. small changes that add up to major changes over a long period of time
- 12. type of fossil that provides evidence of the activities of ancient organisms
- 14. break in the earth's crust
- 16. is the number of years since the rock formed
- 17. group of similar organisms that can mate with each other and produce fertile offspring