The change in frequency of alleles at a locus that occurs by chance is termed as :

Explanation

Genetic drift is the change in frequency of an existing gene variant in the population due to random chance. Genetic drift may cause gene variants to disappear completely and thereby reduce genetic variation. Example: Consider a population of rabbits with brown fur and white fur, white fur being the dominant allele. Due to genetic drift, only the brown population might remain, with all the white ones eliminated. Migration is the seasonal movement of animals from one habitat to another in search of food, better conditions, or reproductive needs. Any change in the DNA sequence of a cell is called a mutation. Non-random mating occurs when the probability that two individuals in a population will mate is not the same for all possible combinations of genotypes.