Natural Selection

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Across
  1. 3. _____ & effect
  2. 6. Characteristics for survival
  3. 7. What would you call a great great grandfather?
Down
  1. 1. How do snow rabbits hide from predators?
  2. 2. To produce and pass out
  3. 4. Building block for genes and chromosones
  4. 5. Gene carrier, XX and XY