Variation

• A wide range of variation in phenotypes due to genetic and environmental factors
• Sources of Variation:

  • Mutation
  • Random fertilisation of gametes
  • Crossing over
  • Independent Segregation
• Variation leads to natural selection e.g. through predetation, disease and competition
• Organisms with phenotypes providing selective advantage are more likely to survive and pass on alleles, changing allele frequency in a gene pool