Across
- 2. to explain how
- 4. most adapted to
- 5. they want
- 7. survive and
- 11. that in layers of
- 16. choose which
- 19. rocks are found at the
- 21. solidified remains or imprints of once-living organisms.
- 23. Remnants of once-useful
Down
- 1. law of superposition
- 3. in its environment.
- 6. to breed to get the
- 8. that helps an
- 9. are solidified remains
- 10. are known as
- 12. and reproduce
- 13. are found at the top and
- 14. environment will
- 15. imprints of once-living
- 17. occurs
- 18. adaptation is a
- 20. rock, younger
- 22. structures.