Question

Which one of the following processes causes the 'Founder effect' in a population?

• A. Genetic drift
• B. Mutations
• C. Natural selection
• D. Genetic recombination

Hint:

The Founder effect and bottleneck effect are both examples of genetic drift occurring in small populations.

Answer 1

The Correct Option is A

Step 1: Understand the Founder effect.
The Founder effect occurs when a small group of individuals separates from a larger population and establishes a new population. Because the new population starts with only a few individuals, its genetic composition may differ significantly from the original population.

Step 2: Understand genetic drift.
Genetic drift refers to random changes in allele frequencies within a population, especially in small populations. These changes occur due to chance events rather than natural selection.

Step 3: Relate Founder effect with genetic drift.
The Founder effect is considered a special case of genetic drift because the new population is formed by a small random sample of the original population. As a result, some alleles may become more common while others may disappear entirely.

Step 4: Analyze mutations.
Mutations introduce new genetic variations into a population, but they are not specifically responsible for the Founder effect. Therefore, option (B) is incorrect.

Step 5: Analyze natural selection.
Natural selection acts on existing variation and favors beneficial traits. It is not the direct cause of the Founder effect. Hence, option (C) is incorrect.

Step 6: Analyze genetic recombination.
Genetic recombination creates new combinations of alleles during meiosis, but it does not cause the Founder effect. Therefore, option (D) is incorrect.

Step 7: Final conclusion.
Thus, the Founder effect is caused by genetic drift.
\[ \boxed{\text{Genetic drift}} \]
Hence, the correct answer is option (A).