Gene flow Knowledge-Based Download PDF

Questions

1. 1.

   In population genetics models, what primary factors directly determine the magnitude of allele frequency change per generation in a recipient population experiencing gene flow?

   • A) The proportion of migrants relative to the recipient population and the difference in allele frequencies between the two populations.
   • B) The total geographic distance between the populations and the baseline spontaneous mutation rate at the locus.
   • C) The absolute carrying capacity of the recipient habitat and the degree of phenotypic dominance of the arriving alleles.
   • D) The operational sex ratio of the donor population and the strength of stabilizing natural selection in the recipient population.
2. 2.

   How does gene flow typically affect the genetic diversity within a small recipient population that previously possessed limited genetic variation?

   • A) It eliminates neutral genetic variation by accelerating the rate of random allele fixation.
   • B) It converts all non-adaptive mutations into selectively favored alleles via assortative mating.
   • C) It increases genetic diversity by introducing new or previously lost alleles into the gene pool.
   • D) It permanently halts genetic change by fixing all loci at Hardy-Weinberg equilibrium.
3. 3.

   How can persistent, high levels of gene flow from a large mainland population most directly hinder the local adaptation of a small peripheral population inhabiting a distinct environment?

   • A) By introducing alleles favored on the mainland that counteract local natural selection and lower average population fitness.
   • B) By accelerating the effects of genetic drift and causing the random fixation of neutral alleles.
   • C) By completely suppressing the occurrence of spontaneous mutations within the peripheral population.
   • D) By rapidly establishing reproductive isolation and triggering ecological speciation between the populations.
4. 4.

   Which of the following conditions is strictly required for the physical movement of organisms between populations to be classified as evolutionary gene flow?

   • A) The migrating individuals must develop reproductive isolation from the resident population upon arrival.
   • B) The recipient population must experience a severe genetic bottleneck prior to the arrival of immigrants.
   • C) Natural selection must strongly favor the immigrant phenotypes over native phenotypes in the local environment.
   • D) The immigrant individuals or their gametes must successfully interbreed and transmit their alleles into the recipient gene pool.
5. 5.

   Which of the following statements best describes the primary evolutionary consequence of ongoing gene flow between two partially isolated populations of the same species?

   • A) It reduces genetic divergence and makes the allele frequencies of the two populations more similar.
   • B) It accelerates speciation by increasing the overall genetic differentiation between the two populations.
   • C) It prevents new mutations from arising in the gene pools of both populations.
   • D) It leads to the complete fixation of identical alleles across all loci through genetic drift.