Across
- 3. Era known as the Age of Mammals
- 5. sudden, violent events, that shaped the Earth
- 8. gradual, continual processes that shaped the Earth
- 9. First organisms to appear, all single celled
- 10. Rock dating method which uses radioactive isotopes
- 12. Fossil type that provides indirect evidence (footprints)
- 15. Era known for evolution of fishes
- 16. Time it takes for half of the parent material to decay
Down
- 1. Era known as the age of reptiles
- 2. Longest unit of geologic time
- 4. Period in Mesozoic where flowering plants evolved
- 6. Rock dating Method used by comparing rock layers
- 7. Eon known for hellish landscape and harsh air
- 11. Explosion of organisms in the fossil record
- 13. Fossilized tree sap, which can trap organisms
- 14. Supercontinent during the time of the dinosaurs
- 17. any preserved evidence of an organism