VARIATION

• VARIATION:

  • DIFFERENCE in the CHARACTERISTICS of an INDIVIDUAL in a POPULATION
• 3 MAIN CAUSES OF VARIATION:

  • GENETICS (inherited ALLELES e.g. EYE colour)
  • ENVIRONMENT (e.g. HEIGHT)
  • A COMBINATION of GENETICS and ENVIRONMENT (e.g. people may have the ALLELES to grow TALL, but their DIET must consist of enough CALCIUM for their BONES to GROW)
• GENETIC VARIATION:

  • Massive amount in any POPULATION of a SPECIES
  • Due to MUTATIONS (random CHANGES in DNA)
• MOST MUTATIONS:

  • Have NO effect on PHENOTYPE
• SOME MUTATIONS:

  • INFLUENCE the PHENOTYPE
• A SMALL NUMBER OF MUTATIONS:

  • DEFINE the PHENOTYPE
• RARELY, MUTATIONS

  • Lead to a NEW PHENOTYPE
  • Beneficial if the ENVIRONMENT changes
  • Can lead to a RAPID change in the SPECIES