Across
- 4. non-living
- 6. population of average traits
- 8. difference in cells
- 10. living
- 11. reproductive success
- 13. make own food
- 14. gradual variation
- 15. important species
Down
- 1. one species is harmed
- 2. eat food
- 3. one species is unaffected
- 5. both species benefit
- 7. variety of life
- 9. one side of population reproduces
- 12. change in the DNA sequence