Across
- 1. Structures that are similar but aren't related organisms
- 4. Diversification of a group of organisms into forms filling different ecological niches
- 6. Occurs when populations are separated by geographic barriers, such as mountains or rivers
- 8. Difference in a physical trait
- 11. Preserved remains of ancient organisms
- 13. When organisms disappear from Earth
- 15. Use of selective breeding to produce organisms with certain desirable traits
- 18. Pattern of evolution where a species is stable for a long time then rapidly changes
- 19. Ability of an individual to survive and reproduce in a specific environment
- 20. Catastrophic events, mass extinction
- 21. Inhabitants of an area
Down
- 2. Another way of saying natural selection
- 3. Change over time
- 5. Ongoing geologic change that adds up over time
- 7. Body parts that have same function but not structure
- 9. Process by which evolution occurs
- 10. Gradual changes from small steps
- 12. Structures that have no current function
- 14. Inherited characteristic that increases an organisms chance of survival
- 16. Ability of a trait to be passed down
- 17. Formation of new species