Across
- 4. Able to "fit in" well
- 8. The best adapted live to reproduce
- 12. Differences in one species
- 13. A group with children who can mate
- 15. Age based on layers
Down
- 1. What remains of a nonliving organism
- 2. Proposed the modern theory of #1
- 3. An explanation to observations
- 5. Change in a cell, leads to #11
- 6. A species' change over time
- 7. Slow change
- 9. All of #3 collected by scientists
- 10. None left
- 11. Arms of a plant connect organisms
- 14. A DNA trait that is passed down