Genetic drift operates only in

Options

A. Larger population
B. Mendelian population
C. Island population
D. Smaller populations

Answer

**Step-by-Step Solution:**

1. **Understanding Genetic Drift**: Genetic drift is a mechanism of evolution that refers to random changes in allele frequencies within a population. It occurs due to chance events that affect which alleles are passed on to the next generation.

2. **Key Characteristics of Genetic Drift**: Genetic drift is particularly influenced by sampling error, meaning that the alleles that are passed on to the next generation may not be representative of the entire gene pool of the current generation.

3. **Impact on Allele Frequencies**: Over time, genetic drift can lead to significant changes in allele frequencies. This can result in the loss of genetic variation, as certain alleles may disappear completely from the population, while others, even if they are rare, may become more common.

4. **Population Size and Genetic Drift**: While genetic drift can occur in populations of all sizes, its effects are much more pronounced in smaller populations. In larger populations, the impact of random sampling errors is minimized because the larger number of individuals tends to buffer against drastic changes in allele frequencies.

5. **Conclusion**: Based on the understanding of genetic drift and its relationship with population size, it can be concluded that genetic drift operates most significantly in smaller populations.

**Final Answer**: Genetic drift operates primarily in smaller populations.

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