Extinction and Evolution

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Across
  1. 2. Any differences in a characteristic within a species
  2. 4. Examples include wings on an ostrich and hip bones in whales
  3. 7. How well-adapted an individual is for survival and reproduction.
  4. 11. This causes dolphins, sharks, and ichthyosaurs to look similar
  5. 12. When individuals struggle against each other for survival
  6. 13. The man who first proposed descent with modification
  7. 15. Large-scale environmental changes that cause many species to die off in a short time.
  8. 16. Examples include the wings of a butterfly and wings of a bird.
  9. 18. Often stated as "survival of the fittest"
Down
  1. 1. The process that moved wolves into dogs.
  2. 3. Any feature that helps an individual survive in its environment.
  3. 5. Archaeopteryx is a famous example of this.
  4. 6. This has led to showy peacock feathers and big horns on bison for fighting.
  5. 8. A human's arm, a whale's front fin, and a bat's wing are all____.
  6. 9. Change in a species over time.
  7. 10. There is no coming back from this.
  8. 14. More of this variety leads to a higher chance of survival
  9. 17. this molecule is the code for all living things.