Evolution Crossword

123456789101112131415161718192021
Across
  1. 2. The movement of alleles between populations
  2. 7. An organism that lives on or in a host and causes harm
  3. 10. An early stage of development before birth or hatching
  4. 12. Preserved remains or traces of ancient organisms
  5. 13. The gradual change in populations over generations
  6. 14. A trait that improves survival or reproduction
  7. 16. A change in DNA that introduces variation into a population
  8. 17. Differences between individuals in a population
  9. 19. A barrier that prevents populations from interbreeding
  10. 20. A source of new genetic variation in populations
Down
  1. 1. An adaptation that helps an organism avoid detection
  2. 3. The disappearance of a species
  3. 4. The formation of a new species
  4. 5. Structures with the same underlying anatomy but different functions
  5. 6. The study of genes and heredity
  6. 8. The process by which advantageous traits become more common
  7. 9. The five-digit limb pattern shared by most mammals
  8. 11. A type of fossil showing features of ancestral and later groups
  9. 14. Structures with similar functions but different underlying anatomy
  10. 15. An organism that hunts other organisms
  11. 18. A different version of a gene
  12. 21. An earlier species from which other species evolved