Variation

• Variation is all the differences in the characteristics of individuals in a population
• Genetic variation:

  • Hair colour
  • eye colour
• Environmental variation:

  • Hydrangeas -
  • The colour of Hydrangeas depends on the pH of the soil. (environmental)
• Some variation is caused by a combination of genes and the environment. e.g -

  • Height in humans (genes produce alleles which make them likely to grow tall. However, their diet must allow them to do so)
• Mutations are random changes to DNA
• Very rarely, mutation can lead to a new phenotype
• In the 1950s a virus spread to the uk and it killed over 99% of wild rabbits. However, a mutation occurred which made the surviving rabbits resistant to the virus ( A new phenotype - Beneficial Phenotype)