Natural Selection

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Across
  1. 2. The black substance that covered trees in England.
  2. 4. What covered the trees before the factories came.
  3. 7. A "Selective ____" is created when an environment changes.
  4. 9. Natural selection takes many of these to happen.
  5. 10. A tiny "typo" in an organism's DNA.
Down
  1. 1. The insect used as a classic example of selection.
  2. 3. A trait that helps an organism survive in its home.
  3. 5. The "filter" that selects which traits work best.
  4. 6. An organism's ability to survive and have babies.
  5. 8. The variety of traits found in nature.