According to the Hardy-Weinberg Theorem, which condition does NOT contribute to constant gene frequencies?

The Hardy-Weinberg Theorem is a principle that provides a framework for understanding how allele frequencies are maintained in a population under certain ideal conditions. The theorem outlines five key conditions that must be met for a population to remain in equilibrium, meaning the gene frequencies will not change over time. These conditions include a large population size, no net mutations, random mating, no migration, and no natural selection.

Natural selection is the process by which certain traits become more favorable and thus more common in a population over generations because they contribute to increased survival or reproductive success. This mechanism leads to changes in allele frequencies as advantageous traits are passed on more frequently than less advantageous ones. Therefore, natural selection disrupts the equilibrium and gene frequencies are not constant under its influence.

In contrast, a large population size minimizes the effects of genetic drift (random changes in allele frequencies), while the absence of mutations ensures that the existing alleles are not altered or replaced. Random mating ensures that allele combinations are produced randomly, maintaining the existing allele frequencies. Thus, each of these conditions contributes to the stability of gene frequencies, except for natural selection, which is inherently a driving force of change.