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Chapter 22-23 - Coggle Diagram

- - - - Origins of Species: Descent with modifications by natural selection explains three broad observations
        
        Linked Coggle
    - - Natural selection increase frequency of adaptations that are favorable in environment **
        
        Adaptive evolution: A process in which traits that enhance survival or reproduction increase in frequency
      - Ways natural selection can alter frequency distribution
        
        Directional Selection: Favors individuals at one extreme end of phenotypic range
        
        Disruptive selection: Favors individuals at both extremes of the phenotypic range
        
        Stabilizing selection: Favors intermediate variants and acts against extreme phenotypes
  - - - Inferences from Observations
        
        Inferences #1: Individuals with traits for increased survival tend to produce more offspring
        
        Inferences #2: The difficulty for a species to survive and reproduce will lead to the accumulation of favorable traits over generations
  - - - Heterozygote advantage: occurs when heterozygote have huher fitness that both kind of homozygotes
- - - - Independent assortment: Random distribution of chromosomes into gametes during meiosis
      - Fertilization: Random combination of gametes
      - Rossing over: Exchange of genetic material between homologous chromosomes during meiosis
- - - - "Same structure, different functions"
    - - "Structure still present, but not necessary for survival"
  - - - Certain strains, called methicillin-resistant S. aureus are pathogens which is very fatal since they grow immune to drugs rapidly
    - - Herbivores often have adaptations to help feed efficiently on their primary food source