Across
- 2. Dinosaurs started to appear in this Period
- 4. Humans evolved and exist in this Period
- 6. The first land plants started to appear in this Period
- 8. The biggest extinction in the Earth's history
- 11. The name given to a time when there was not much complex life
- 14. These have been responsible for a couple of major extinctions
- 15. Dinosaurs became extinct at the end of this Period
- 17. This was the start of the Palaeozoic and a specific Period
Down
- 1. These allow new animals to become the dominant species on Earth
- 3. The Era in which we live currently
- 5. This is the Period where most of Britain's coal was formed from
- 7. This is how 'Billion years' should be shortened to
- 9. This is how 'Million years' should be shortened to
- 10. First land animals appear
- 12. 4.5 of these is equal to the Earth's age
- 13. This was a fossil which lived around 16Ma
- 16. This Period ended 420Ma