Across
- 2. An element that is used to date rocks or non-living things
- 6. Segment of Earth that helps life
- 10. Dinosaurs that use only two legs
- 11. This was when the oceans formed and the animals and plants appeared; first of three eras after precambrian
- 15. A scientist that studies fossils\
- 16. Lizard-hipped dinosaurs
- 19. Rock that change from pressure and heat from the Earth
- 21. This was the era of dinosaurs; second era after precambrian
- 22. Warm blooded vertebrates; feeds its young milk
- 24. A Supercontinent
- 26. Animals that have no backbone
- 28. Dinosaur dung that has been fossilized
- 29. Rocks that are formed from cooled magma
Down
- 1. Remain or traces of living things that have been preserved
- 3. Bird-hipped dinosaur
- 4. All the Water on the Earth
- 5. Dinosaurs that use all four legs
- 7. The rate of decay of a radioactive element
- 8. A Gradual change in living things over long periods of time
- 9. Rock that is formed from pressure and heat of the earth; also are the layers of the Earth
- 12. Outer crust and mantle of the Earth
- 13. Cold blooded vertebrates
- 14. Rocks that are found in the digestive system of dinosaurs
- 17. Animals that have a backbone
- 18. Scientist that study origin, history and structure of the Earth
- 19. A large amount of living things become extinct all at once
- 20. Gases that are surrounding the Earth
- 23. A theory that says the universe was created by a large explosion
- 25. This is the present; the last of three eras after precambrian
- 27. Used to date things as old as 50,000 years old; used to date living things