All of the above factors contribute to the reduction of gene pools in small populations. Small populations have less genetic variation and are more susceptible to genetic drift, which can lead to the fixation of harmful or neutral alleles. Inbreeding can also increase the frequency of deleterious alleles and reduce the fitness of the population. Bottleneck events, which occur when a population is drastically reduced in size, can result in a loss of genetic diversity if only a small subset of alleles are passed on to future generations. Overall, smaller populations have less genetic variation and are more vulnerable to the negative effects of genetic drift, inbreeding, and bottlenecks.
