Variation

• Variation


  All the differences in the characteristics of individuals in a population
• Causes of variation


  • Alleles inherited
  • Environmental factors
  • Combination of genes and environment
• Genetic variation


  • Examples: hair color, eye color
• Environmental variation


  • Examples: flower color, language
• Variation from genes and environment


  • Example: height in humans
• Mutation


  Random changes to DNA
• Most mutations have no effect on the phenotype
• Some mutations can influence the phenotype
• A small number of mutations determine the phenotype
• Beneficial mutation


  A mutation that leads to a new phenotype that is advantageous in a changed environment