Final answer:
Natural selection can disrupt Hardy-Weinberg equilibrium through processes like genetic drift, the bottleneck effect, the founder effect, gene flow, mutations, and nonrandom mating, ultimately facilitating microevolution.
Step-by-step explanation:
Natural selection can cause Hardy-Weinberg (HW) disequilibrium at nuclear loci in various ways. One significant factor is the genetic drift, which tends to be more pronounced in small and isolated populations. Events like the bottleneck effect and the founder effect can reduce genetic variation within a population, which is the basis for natural selection. Moreover, gene flow, mutations, and nonrandom mating can all lead to changes in a population's allele frequencies, hence causing deviations from HW equilibrium. These deviations from equilibrium can result in the microevolution of a population.