1. Genetic Equilibrium Allele frequency in a gene pool is not changing
Hardy Weinberg
Disruption of Equilibrium = Change

2. 1. Natural Selection

3. Types of Natural Selection
Directional Selection - extreme phenotype has higher fitness
Peppered Moth

4. Stabilizing Selection - intermediate phenotype has a higher fitness

5. Disruptive Selection - intermediate phenotypes are of lower fitness than extreme phenotypes

6. 2. Mutation Neutral mutation – no impact on survival or reproduction
Beneficial mutation – increase in survival or reproduction

7. 3. Gene Flow/Migration Individuals enter or leave a population
emigrate = lose alleles
immigrate = gain alleles

8. 4. Genetic Drift
Unpredictable changes in allele frequency due to small population size
Population bottleneck –reduction of a population
Founder Effect – individuals leave a population and establish a new one

9. 5. Nonrandom Mating Choosing a mate
Sexual Selection – ability to attract a mate

10. Coevolution
Change of two or more species in close association with each other
Predators and prey
Parasites and hosts
Plant eating animals and plants

11. Convergent Evolution
Environment selects similar phenotypes although ancestral types were different
Sharks and dolphins

12. Divergent Evolution
Two or more related populations or species become more and more different
Response in differing habitats
Result in new species

13. Adaptive Radiation
Many related species evolve from a single ancestral species

14. Artificial Selection
Intentional breeding for specific traits

15. Rates of Evolutionary Change
Rapid rates of evolution occur when conditions favor new traits
Otherwise evolution is slow
Based on many factors
Mutation rate, lifespan of organism

16. Rate of Speciation

17. Patterns of Evolutionary Change
Novel features evolved infrequently
Most changes are modifications
Organisms have increased in size and complexity
Predations rates increased = evolution of better defenses

19. Why don’t horses have wheels?

20. Explain why variations in a population are seen as a bell shaped curve.
Agenda Tuesday May 31st
Patterns and Mechanism notes
Peppered moth thing

22. Describe convergent evolution.
Agenda for Wednesday June 1st
Finish notes
Finish peppered moth
Evidence of Evol.