7.4.A—Explain how random occurrences affect the genetic makeup of a population

Explain how random occurrences affect the genetic makeup of a population.

• Evolution is also driven by random occurrences.
  • i. Mutation is a random process that adds new genetic variation t o a population.
  • ii. Genetic drift is a change in allele frequencies attributable to a nons elective process occurring in small populations. iii.The bottleneck effect is a type of genetic drift that occur s when a population size is reduced to a small number of individuals for at least one generation. iv.The founder effect is a type of genetic drift that occur s when a population is separated from other members of the population. The frequency of genes and traits will shift based on the genes in this new founder population.
  • v. Migration can result in gene flow (the addition or remov al of alleles from a population).