Natural Selection

2. A random change in a gene that results in a different trait
4. the reproductive organs do not match up
6. barriers that take effect before fertilization
9. heterozygous
11. differences in mating habits that prevent species from intermixing
12. different structures that have similar functions.
13. random event that severely decreases the population and leaves random survivors
15. Similar structure, different function
17. a diagram that depicts the lines of evolutionary descent of different species, organisms, or genes from a common ancestor.
18. homozygous recessive
21. barriers that take effect after fertilization.
22. no mutation, random mating, no gene flow, infinite population size, and no selection.
23. species mating at different times

1. ________happens because more babies are born than there are resources to support them
3. the maximum population size an ecosystem can support sustainably
5. infertile offspring is produced
7. Gametes cannot form a zygote
8. ____evolve, not individuals
10. zygote does not live to maturation
14. distantly related species, independently evolving similar traits due to similar environments or environmental pressures.
16. Naturalist who worked with tortoises in the Galapagos
19. a role an organism plays in a community
20. survival of the...
24. homozygous dominant