Natural Selection

2. when allele frequency is high in the mean range and decreases toward each extreme
5. evolution of one or more closely related species into different species
12. when 2 opposite, uncommon phenotypes are selected over the most common phenotype
13. elimination of a species from Earth
14. when members of isolated populations aren't able to reproduce or mate or produce viable offspring
15. process when 2 or more species evolve in responses to change in each other
16. collection of alleles
18. isolation due to barriers related to time
19. the process by which different kinds of living organisms are thought to have developed and diversified from earlier forms during the history of the earth
20. isolation due to differences of mating behavior
22. evolution towards similar characteristics in unrelated species
23. observable change in the allele frequencies of a population over a few generations
24. genetic drift that occurs after a small number of individuals colonize a new one
25. when certain traits enhance mating success

1. when one uncommon phenotype is selected over the most common phenotype
3. theory that says speciation occurs rapidly and is followed by long periods of small evolutionary changes
4. proportion of one allele compared with all the alleles for that trait in one gene pool
6. when intermediate phenotypes are selected over phenotypes at both extremes
7. change in allele frequencies
8. when a populaton's allele frequencies for a given trait do not change from generation to generation
9. isolation between populations due to physical barriers
10. physical movement of alleles from one population to another
11. evolution of 2 or more species from one ancestral species
17. when one species evolves and gives rise to descendant species that have different niches
21. genetic drift that results from an event that reduces the size of the population