Across
- 2. living matter turned to stone
- 3. something you know is true and has happened
- 5. the bird Darwin noticed that had different varieties
- 8. periods are divided into ___
- 9. darwin was a keen observer of ____
- 11. some people believe all creatures are created by ___
- 12. eons are divided into ___
- 14. life on earth began from a ___ cell
- 18. largest division of geological time
- 19. fossils provide ____ of something that was once alive
- 20. the earth formed 4.5 ___ years ago
Down
- 1. the closest living relative of humans
- 4. we live in this eon
- 6. man who doubted that god created all beings
- 7. scientific name of humans
- 10. ___ tells us how life formed and changed over the years
- 13. all continents were one huge landmass called ___
- 15. the oldest object on earth are these type of rocks called ___
- 16. eras are subdivided into ____
- 17. when a species no longer exists