# Population Genetics > [!example] Quantifying Evolution in Natural Populations > 1. Calculate the expected genotype frequencies when NO [[evolution]] is occurring (i.e. random mating). This is often done through the use of [[hardy-weinberg equilibrium]]. > > 2. Sample a population of interest and see if the observed genotype frequencies are **significantly different** when no evolution is occurring. > > 3. If the frequencies are different, this is evidence that the population is evolving.