Microevolution

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Microevolution

• Changes within a species

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Microevolution

• Change in the gene pool of a population
• Change in the relative frequency of a population
• Evolution on the smallest scale
• Leads to MACROevolution

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Causes of Microevolution

• Genetic Drift
• Changes in gene pool of a small pop. due to
  random chance
• Bottleneck effect
• Founder effect
• Gene Flow
• Change in gene pool due to migration of fertile
  individuals

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• Mutation
• Introduction of a new allele
• Nonrandom Mating
• Mates not randomly selected
• Sexual selection
• Natural Selection
• Differential reproductive success
• Some phenotypes are selected against

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Case Study - beetle

• Population group of organisms that interbreed

Tree of Life
Insects
Beetles
Species
6
Sample of Beetle Genes
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Mechanisms

• Mutations
• Some green genes mutated to brown
• Migrations
• Beetles with brown genes migrated to the area

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• Genetic Drift
• Random chance caused there to be more brown than
  green genes
• Natural Selection
• Brown beetles escaped predation and survived to
  reproduce