Speciation

6. form of reproductive isolation in which two populations are separated by geographic barriers such as rivers, mountains, or bodies of water, leading to the formation of two separate subspecies.
7. number of times that an allele occurs in a gene pool compared with the number of alleles in that pool for the same gene.
8. separation of a species or population so that they no longer interbreed and evolve into two separate species.
9. form of natural selection in which individuals near the center of a distribution curve have higher fitness than individuals at either end of the curve.
10. formation of a new species.
11. a group of similar organisms that can breed and produce fertile offspring.

1. form of reproductive isolation in which two populations develop differences in courtship rituals or other behaviors that prevent them from breeding.
2. form of natural selection in which individuals at one end of a distribution curve have higher fitness than individuals in the middle or at the other end of the curve.
3. when individuals select mates based on heritable traits.
4. natural selection in which individuals at the upper and lower ends of the curve have higher fitness than individuals near the middle of the curve.
5. a change in the ratio of alleles following a dramatic reduction in the size of a population.
6. random change in allele frequency caused by a series of chance occurrences that cause an allele to become common in a population.