Final answer:
Selective advantage disrupts the Hardy-Weinberg equilibrium by providing certain alleles with increased fitness, leading to a change in allele frequencies over generations, thus causing evolution.
Step-by-step explanation:
Effect of Selective Advantage on Hardy-Weinberg Equilibrium
The Hardy-Weinberg equilibrium is a principle that predicts that allele and genotype frequencies in a population will remain constant from one generation to the next, given that certain assumptions are met. These assumptions include no natural selection, no mutation, no genetic drift, no migration, random mating, and an infinitely large population size. However, if a selective advantage exists for certain alleles, it would disrupt this equilibrium.
Selective advantage means that certain alleles provide a benefit to those who possess them, increasing their chances of survival and reproduction. If these advantageous alleles lead to higher fitness, they will change in frequency over generations, contrary to the Hardy-Weinberg expectation of stable allele frequencies. This can cause evolution as advantageous alleles become more common, potentially leading to adaptation.
Thus, a selective advantage impacts the Hardy-Weinberg equilibrium by changing allele frequencies in a population over time, which signifies that evolution is occurring. The Hardy-Weinberg model serves as a baseline for scientists to compare real population genetics and to judge the influence of evolution.