Across
- 3. what period did the earth look like it is now
- 4. how many periods are in the Carboniferous period in the U.S.
- 7. how much C02 was there in the beginning of the earth
- 9. how old is the earth
- 10. how many periods are there in the Palaeozoic age
- 11. how many layers are in the earth
Down
- 1. how many dino types are there
- 2. what percent of fish did the meteor wipe out
- 4. what was the largest plant type called in the Triassic period
- 5. what continent did humans evolve from
- 6. what modern day country did the meteor hit that made the dinos extinct
- 8. what are bones of deceased animals called