Question

In random mating population in equilibrium, which of the following brings about a change in gene frequency in a nondirectional manner?

• A. Mutations
• B. Random drift
• C. Selection
• D. Migration

Answer 1

Answer: (B)

Random drift

Random drift is a non-directional factor. In actual practice, gene frequencies due to random drift may approach limits, i.e.; 1 and 0.

This would simply be possible only when a new population arises due to a very small sample leading to the fixation of one allele at the cost of another.

In this manner, the changes in gene frequency can be brought about without the existence of any directional force, i.e; mutation, selection and migration and this change has been called random genetic drift.

Thus, Random drift brings about a change in gene frequency in a non-directional manner in a random mating population at equilibrium. Thus, Option b is correct.