1. Genetic Drift

2. Drawn to Scale
High Chair
Flat Tire

3. Genetic Drift
Target: I will be able to define genetic drift, explain how founder and bottleneck effects result in genetic drift
Genetic Drift: Chance events (not Natural Selection) that change the genetic composition of a population
These random events change the allele frequencies over time.
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4. They reduce the amount of genetic variation in the population
Can cause fixation of one allele (One allele occurring over and over)
Genetic Drift

5. Two types of Genetic Drift:
1. Founder Effect: The loss of genetic variation when a new colony is formed by a very small number of individuals (founders) from a larger population.
Example: Polydactyly (extra fingers/toes) in the Old Order Amish of Pennsylvania

6. Gene Disorders Hit Amish Hard

7. 2. Bottleneck Effect: The dramatic loss of genetic variation due to environmental effects or human activities.

8. Ex: Earthquakes, fires, droughts, over hunting, destroying habits
Summary:

9. Two Types of Drift Founder Effect Bottleneck Effect
Draw a real life example for each type of genetic drift, and the effects on the resulting populations
*Use a minimum of 4 colors
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