Biology Chapter 15

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Across
  1. 4. Darwin brought these birds back from the Galapagos
  2. 7. English mathematician
  3. 9. cumulative changes in groups of organisms
  4. 11. when a small sample of a population settles in a location separated from the rest of the population
  5. 12. operates to eliminate extreme expressions of a trait
  6. 13. there are ___ basic principles for natural selection
  7. 15. a measure of the relative contribution that an individual trait makes to the next generation
  8. 16. structures that are reduced forms of functional structures in other organisms
  9. 19. when a population declines to a very low number and then rebounds
  10. 20. a process that splits a population into two groups
  11. 21. another type of morphological adaptation to make one species look like another
Down
  1. 1. study of the distribution of plants and animals around the world
  2. 2. an early, pre-birth stage of an organism
  3. 3. morphological adaptations that allow them to blend in with their environments
  4. 5. anatomically similar structures inherited from common ancestors
  5. 6. are newly evolved features
  6. 8. any change in the allelic frequencies in a population that results from change
  7. 10. a random change in genetic material
  8. 14. developed the theory of evolution
  9. 15. a ___ can provide a record of species that lived long ago
  10. 17. German physician
  11. 18. primitive features