[Campbell Biology P.546] Distinguish genetic drift from gene flow in terms of a how they occ... | Practice Question

Distinguish genetic drift from gene flow in terms of a how they occur and b their implications for future genetic variation in a population.

  • A: Genetic drift occurs due to random chance events, reducing genetic variation, while gene flow involves allele transfer between populations, often increasing variation within a population and reducing differences between populations.
  • B: Genetic drift increases genetic variation through mutation, while gene flow consistently reduces it.
  • C: Gene flow is always adaptive, whereas genetic drift is always maladaptive.
  • D: Both genetic drift and gene flow are mechanisms that consistently lead to adaptive evolution.

Explanation

Genetic drift is a random process, especially significant in small populations, causing allele frequencies to fluctuate unpredictably and potentially leading to a loss of genetic variation. Gene flow, on the other hand, is the movement of alleles between populations e.g., via migration of individuals or gametes . It tends to make populations more similar genetically and can introduce new alleles, thus increasing variation within a population while reducing differentiation between populations.