Variation

• Differences in the characteristics of individuals in a population is called variation and may be due to differences in:

  • the genes they have inherited
  • the conditions in which they have developed
  • a combination of the above
• There is usually extensive genetic variation within a population of a species
• All variants arise from mutations and most have no effect on the phenotype, some influence phenotype, very few determine phenotype
• Mutations occur continuously.
• Very rarely a mutation will lead to a new phenotype. If the new phenotype s suited to an environmental change it can lead to a relatively rapid change in the species