Which of the following is NOT a condition of Hardy-Weinberg Equilibrium?

Hardy-Weinberg Equilibrium is a fundamental principle used in population genetics to describe a population that is not evolving. For a population to be in Hardy-Weinberg Equilibrium, several specific conditions must be met. These include the absence of mutations, migration (both immigration and emigration), natural selection, and a very large population size to minimize the effects of genetic drift.

The condition concerning "No reproductive barriers" is not one of the standard conditions for Hardy-Weinberg Equilibrium. Reproductive barriers, which can include prezygotic and postzygotic mechanisms that prevent successfully producing fertile offspring, do not inherently conflict with the assumptions of Hardy-Weinberg Equilibrium. In fact, populations can still maintain Hardy-Weinberg conditions in the presence of reproductive barriers, provided that the remaining conditions are met.

Thus, the presence of reproductive barriers can affect the gene flow and genetic structure of populations but does not directly violate any of the conditions necessary for Hardy-Weinberg Equilibrium. The focus of Hardy-Weinberg is primarily on factors that change allele frequencies within the population rather than those that influence mating and fertilization success.