Geologic Time
Across
- 3. This era, another word for "ancient life" came during a time when most organisms were simple marine animals
- 4. The era in which humans exist
- 6. The largest divison of time
- 7. The smallest division of time
Down
- 1. A subdivision of an era
- 2. This era ended in the extinction of dinosaurs
- 5. A subdivision of an eon