Consider a population of Pacific tree frogs (Pseudacris regilla). In this population of frogs, a single locus controls the production of a mating call. This locus has two alleles - S1 and S2. You observe the following genotype counts:
S1S1 = 987
S1S2 = 333
S2S2 = 21
Use these data to calculate the chi-square statistic. Report your calculated chi-square statistic to two decimal places.