The Hardy Weinberg Law states that if evolution isn't occurring, an equilibrium of allele and genotype frequencies is passed on through generations among sexually-reproduced species. This law assumes an ideal process that isn't possible but can determine if evolution is occurring.
The Hardy Weinberg law is represented by the following two equations: p + q = 1 and p^2 + 2pq + q^2 = 1. In the first equation, the "p" represents the frequency of the dominant allele, and the "q" represents the frequency of the recessive allele in the population. In the second equation, "p^2" represents the percentage of homozygous dominant individuals, and the "q^2" represents the percentage of homozygous recessive individuals. The "2pq" represents the percentage of heterozygous individuals. Additionally, there are conditions that must be met for this law to be effective.