Download Patterns_of_Evolution_1_Notes

Patterns of Evolution Notes Part 1
Name: ___________________________
Honors Biology
A. Mechanisms of Evolution
How might variation occur in a single population?
I.
Genetic Variation
1. Mutations
Some mutations are not inherited (do not get passed on)
Example:
Some mutations are inherited (do get passed on)
Example:
Example:
2. Sex (gene shuffling)
How does sex maintain genetic diversity?
How might variation occur between different populations?
II. Gene Flow (Migration): any movement of genes (genetic info) from one population to another.
How might gene flow happen?
Example:
Example:
III. Genetic Drift: Individuals in a population survive and reproduce due to _____________
chance. NOT because they are more “fit,” as in ____________ _____________.



Genetic drift _________________ diversity within a population
Genetic drift impacts the diversity of ______________
populations.
Genetic drift can create a “_________________ effect” or
“_______________ effect.”
1. Bottleneck Effect: A random event dramatically decreases the population size (and,
therefore, _______________ ______________) for at least one generation.
Example:
Example:
2. Founder Effect:
A few members of an original population colonize a new population.
 The founders may not accurately represent the _______________ makeup of the original
population.
 Genetic diversity may _________________.
Example:
Example:
IV. Natural Selection
1. Stabilizing Selection in your own words:
Example:
Example:
2. Directional Selection in your own words:
“Natural Selection at work”
Example:
Example:
3. Disruptive Selection in your own words:
Example: