Across
- 6. based on mating success
- 12. preserved remains of organisms
- 13. version of a gene
- 14. classification system
- 16. favoring average traits
- 17. similar structure from common ancestor
- 19. observable characteristic
- 21. shared origin of species
- 23. reduced unused structure
- 24. evolutionary history
- 25. change in populations over time
- 26. survival of better adapted organisms
Down
- 1. ability to survive and reproduce
- 2. formation of new species
- 3. physical trait expression
- 4. genetic makeup
- 5. favoring one extreme trait
- 7. differences within a population
- 8. environmental factor affecting survival
- 9. diagram of relationships
- 10. trait that improves survival
- 11. variety of living things
- 15. favoring both extremes
- 18. DNA change creating new traits
- 20. similar function different origin
- 22. loss of a species