What evolutionary mechanism is primarily responsible for random changes in allele frequencies within small, isolated populations due strictly to chance events rather than natural selection?
Answer and explanation
Correct answer: A. Genetic drift
- Step 1: Define stochastic evolutionary processes.
- Step 2: Genetic drift (including the bottleneck and founder effects) refers to random fluctuations in allele frequencies between generations resulting purely from chance sampling errors in small populations.
Answer
Genetic drift.
Why not the others: Gene flow involves migration between populations; mutation introduces new variants; sexual recombination shuffles alleles without changing population allele frequencies on its own.
Practise more Organisms, Evolution and Ecosystems.
Free questions with an explanation for every one, and full timed EmSAT Achieve (UAE) mock tests.
More Organisms, Evolution and Ecosystems questions
- In humans, hemophilia A is an X-linked recessive disorder. A carrier woman (XᴴXʰ) and an unaffected man (XᴴY) have children. What is the pro…
- In a population in Hardy-Weinberg equilibrium, the frequency of a recessive allele (q) is 0.20. What percentage of the population is expecte…
- Which part of the human nephron is primarily responsible for establishing a high hypertonic osmotic gradient in the renal medulla via a coun…
- According to Lindeman's efficiency rule in ecosystem ecology, approximately what fraction of energy is transferred from one trophic level to…
- What type of natural selection favors individuals with intermediate phenotypes while acting against extreme phenotypic variants at both ends…
- Which chamber of the human heart pumps oxygen-rich blood into the systemic aorta under high systolic pressure?