Seeing%20is%20Believing:%20Evolution%20in%20your%20Classroom

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Seeing is Believing Evolution in your Classroom

• Anne Royer Jay Sobel

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(No Transcript)
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pre test here
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review the necessary requirements

• 3 necessities for evolution by natural selection
• phenotypically variable population
• relationship between a trait and fitness
• genetic basis to trait (heritable)
• other necessities specific to classroom
• something that reproduces quickly enough to see
  several generations in one semester or year
• organisms that are easy to obtain and maintain
• at least 2 selective environments
• easy to measure traits with simple tools
• others generated by teachers

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Phenotypic Variation
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Relationship between Trait and Fitness (Selection)
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Genetic Basis to Trait (Heritability)
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Artificial Selection

• Human imposed selection
• Test for Heritability
• R h2S
• response to selection heritability x selection
  strength
• Used for plant and animal breeding for thousands
  of years

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Connecting Artificial Selection to Natural
Selection

• Selection imposed by environment
• could include abiotic sources like climate,
  soils, etc.
• biotic sources like mutualists or predators
• Strength of selection imposed may be strong or
  weak (unlike artificial selection), but lots of
  time involved