AP Biology Chapter 18 Vocabulary Crossword

4. speciation that happens through geographic separation (2 words)
10. modifications caused by the environment that can be inherited (2 words)
12. offspring of two closely related species (1 word)
13. shows how species diverge gradually over time (3 words)
18. heritable trait in an organism that aids in survival (1 word)
19. differences in breeding schedules (2 words)
21. groups of organisms that independently evolve similar forms (2 words)
22. speciation that happens in the same geographic area (2 words)
23. prezygotic barrier occurring when closely related species mate but differences in gametes prevent fertilization (2 words)
25. type of reproductive isolation that happens when a population of a species move habitats (2 words)

1. type of reproductive isolation that occurs when a specific behavior (or lack of one) prevents reproduction (2 words)
2. reproductive isolation that occurs after zygote formation (2 words)
3. reproductive isolation that occurs before zygote formation (2 words)
5. parallel structures in organisms that have a common ancestor (2 words)
6. gametes with extra chromosomes (1 word)
7. groups of organisms evolve in different directions from a common ancestor (2 words)
8. physical structure in an organism that has no apparent function (2 words)
9. rapid speciation that can happen when an event causes a population to be cut off from the rest of the species (2 words)
10. speciation when one species radiates out to form other species (2 words)
11. populations change over time (3 words)
14. cell having an extra chromosome or missing a chromosome (1 word)
15. formation of a new species (1 word)
16. speciation that occurs when a few members of a species move to a new geographical area (1 word)
17. genetic differences among individuals in a species (1 word)
20. reproduction of individuals with favored genetic traits that survive longer than others of the same species (2 words)
24. area where two closely related species interact (2 words)