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