The Hardy-Weinberg equation is a mathematical formula used to predict genotype frequencies in an idealized population that is not evolving. Here's what the equation tells us about genotype frequencies in an equilibrium population:
1. Genotype frequencies do not change over time: The main implication of the Hardy-Weinberg equilibrium is that in the absence of evolutionary forces like natural selection, genetic drift, mutation, or gene flow, the frequencies of genotypes in a population remain constant from generation to generation. This means that the proportion of genotypes (e.g., AA, Aa, aa) will stay the same over time.
2. Genotype frequencies can only be expressed in terms of allele frequencies: The Hardy-Weinberg equation relates genotype frequencies to allele frequencies in a population. It demonstrates that under specific conditions (no mutation, no natural selection, random mating, large population size, and no gene flow), the frequencies of alleles in a population will remain constant, and from these allele frequencies, we can deduce the frequencies of genotypes.
Therefore, the correct answer is:
- a. Genotype frequencies do not change over time.
This understanding is crucial for population genetics as it provides a baseline to compare real-world populations against and helps scientists study evolutionary processes within populations.
