Given below are two statements.

Statement I : Changes in allelic frequencies occurring by chance in a population is know as genetic drift.

Statement II : Gene flow or gene migration is the only cause of genetic drift in a population.

In light of the above statements, choose the correct answer from the options given below.

Statement I is correct but statement II is incorrect.

• Statement I is true. Genetic drift refers to the random fluctuations in allelic frequencies that occur in a population over time due to chance events. These chance events can include factors such as random mating, chance deaths, or the random distribution of offspring.
• Statement II is false. Gene flow, also known as gene migration, involves the movement of genes between populations through the migration of individuals. Gene flow tends to reduce genetic differences between populations and increase genetic variation within populations. However, genetic drift is specifically caused by random chance events within a population, not by gene flow. In fact, gene flow tends to counteract the effects of genetic drift by introducing new alleles into populations and preventing genetic divergence.