In a wild population of the pocket mouse (Chaetodipus intermedius\textit{Chaetodipus intermedius}Chaetodipus intermedius) inhabiting a dark basaltic lava flow, fur coat color is controlled by a single gene with two alleles. The allele for dark-colored fur (DDD) is completely dominant over the allele for sandy-colored fur (ddd).
A field survey of a representative sample of 800 mice from this population reveals that 728 individuals exhibit dark-colored fur, while the remaining individuals have sandy-colored fur.
Assuming the population is in Hardy–Weinberg equilibrium for this locus, calculate the percentage of mice in this population that are heterozygous (DdDdDd) for the fur color gene.
