CHAPTER 17 - Variation and Selection

• Variation is the differences between the individuals of the same species
• Continuous variation is a continuous range of phenotypes between two extremes
• Discontinuous variation is when there are distinct categories of phenotype
• Variation caused by gene is passed on to an organism's offspring
• Variation caused by the environment isn't passed on
• Causes of genetic variation

  Mutation is a random change in a gene which can produce new alleles which involves a change in the base sequence in DNA
• Natural selection is the process by which individuals with advantageous features are more likely to survive, reproduce and pass on their alleles to the next generation
• Selective breeding is the process of breeding organisms to produce offspring with desirable characteristics.