The smaller a population, the greater the potential effect of genetic drift on gene frequencies. Genetic drift is an evolutionary term which refers to the random changes in a population's allele frequencies. These changes happen by chance due to the random selection of alleles from the genetic pool in each generation. Genetic drift can lead to either loss of some alleles or the fixation of others (100% frequency). The effect of genetic drift is stronger in smaller populations. This is because, the larger the population, the larger the sample size and the slower the result of genetic drift.
