Geologic Time Scale

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Across
  1. 2. Diversification within phyla
  2. 3. Major event 2.5 bya
  3. 7. Period with vast, swampy forests
  4. 10. Age of fishes
  5. 11. Subdivision of an era
  6. 12. The most successful eukaryotic lineage
  7. 13. Largest time division
  8. 15. Eon where life first appeared
  9. 16. Where geologic history is recorded
Down
  1. 1. 88% of Earth's history
  2. 4. Major event 1.5 bya
  3. 5. Second longest time decision
  4. 6. Major event 3.8 bya
  5. 7. Period of explosive radiation of life
  6. 8. Invasion of land
  7. 9. Eon where atmospheric oxygen and single celled eukaryotes appeared
  8. 11. Assembly of Pangaea
  9. 14. Smallest unit of time