Question

Random genetic drift in a population probably results from

• A. Highly genetically variable individuals
• B. Interbreeding within this population
• C. Constant low mutation rate
• D. Large population size

Answer 1

The Correct Option is B

Random genetic drift refers to changes in the frequencies of alleles (gene variants) in a population that occur due to chance rather than natural selection. This process plays a more significant role in small populations where random events can disproportionately affect gene frequencies.

Let's evaluate the options provided:

1. Highly genetically variable individuals: While genetic variability is essential for evolution and adaptability, it is not directly related to genetic drift. Genetic drift can occur regardless of the variability within individuals.
2. Interbreeding within this population: Interbreeding, or reproduction among individuals within a small population, can lead to genetic drift. This is because reproduction is largely random, and certain alleles might increase or decrease in frequency by chance, causing variation in allele frequencies over time.
3. Constant low mutation rate: Mutation introduces new genetic material into a population but at low rates typically has minimal effect compared to genetic drift, especially in small populations. Moreover, drift is independent of mutation rates and is more about allele frequency changes due to random sampling.
4. Large population size: In large populations, genetic drift has less impact because the law of large numbers averages out random fluctuations, making significant allele frequency changes less likely due to chance alone.

From this analysis, the correct answer is "Interbreeding within this population." This creates a context where random mating and limited population size enhance the impact of genetic drift.