1. Study of Microevolution
Population Genetics
Study of Microevolution

2. Gene Pools
A population’s gene pool is the total of all genes in the population at any one time. 
Population - a localized group of individuals of the same species. 
Species - a group of populations whose individuals have the ability to breed and produce fertile offspring. 

3. The Gene Pool Different species do NOT exchange genes by interbreeding
Different species that interbreed often produce sterile or less viable offspring e.g. Mule

4. The Hardy-Weinberg Theorem
Idealized mathematical model of gene pools.
Predicts a relationship between
-allele frequencies in the gamete pool
-genotype frequencies in the next generation
Used to describe a non-evolving population. 
 Natural populations are NOT expected to actually be in Hardy-Weinberg equilibrium.

5. Assumptions of the H-W Theorem
Organism is diploid
Generations are nonoverlapping
Large population size
No net mutations
Reproduction is sexual
6. Random mating
7. No migration
8. No natural selection

6. Causes of microevolution : (changes in gene pools)
                       
1. Natural selection
2. Genetic drift
3. Mutation
4. Gene Flow

7. Sickle Cell and Malaria
English Peppered Moth
Sickle Cell and Malaria 7 7

8. Gene Flow genetic exchange due to the migration of fertile individuals or gametes between populations.

9. Mutations The original source of variation.
Beneficial mutations are favored by natural selection and so increase in frequency in the gene pool
Mutations can be transmitted in gametes to offspring, and immediately affect the composition of the gene pool.

10. Why is genetic variation important?
survival
global
warming
variation
EXTINCTION!!
no variation

11. the alteration of the gene pool of a small population due to chance
Genetic drift
the alteration of the gene pool of a small population due to chance
may cause genetic drift:                   
Founder effect
Bottleneck effect