BIO 258 Notes
WEEK #7.
NATURAL SELECTION
- Adaptation. (Futuyma ch. 12; Minkoff ch. 10; E17).
- Structural adaptations
- Biochemical adaptations
- Color & pattern adaptations:
camouflage, industrial melanism, mimicry
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- Selection for single-gene traits
(Futuyma ch. 13; Minkoff Ch. 11; E18).
- Survivorship & fitness coefficients
- Selection against dominants
- Selection against recessives
- Selection agaiunst heterozygotes
- other possibilities
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- Selection for quantitative traits (Futuyma ch. 14; E19)
- Forms of selection:
- Stabilizing (centripetal) selection (e.g., Bumpus' sparrows)
- Disruptive (centrifugal) selection
- Directional selection
examples: Aristelliger, corn, mice, humans
- Agents of selection:
- Artificial selection (by human agency)
- Natural selection (by natural agency)
- by predators
- by pathogens, parasites, & other diseases
- by starvation
- by environmental (climatic) extremes (of temperature, etc.)
- other physical agents: fire, landslides, etc.
- sexual selection
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- Persistence of variability (Minkoff Ch. 12; E20)
- Importance of maintaining variability
- Forces that erode variability
- Maintaining variability cytologically
- Maintaining variability ecologically:
polymorphism; maintaining balanced polymorphism
- Measuring genetic variability in populations; electrophoresis
- Neutral gene theory, etc.
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BIO 258 Syllabus
revised March 2003 (4)