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Unformatted text preview: Directional Selection In directional selection the population consistently shifts toward a phenotype that is favored at the expense of others. This differs from stabilizing selection where extremes are reduced at both ends of the variation continuum. Directional selection is typically a response to a changing environmental condition or to a new environment. Some examples of directional selection include: Peppered moth mentioned earlier is a dimorphic population where the shift has been to the dark form in response to pollution Resistance to pesticides is common in many organisms Most induced selection or artificial selection is directional. We narrow the population for some characteristic....
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This note was uploaded on 12/29/2011 for the course BIO 151 taught by Professor Edwards during the Spring '10 term at SUNY Stony Brook.
- Spring '10