Problem:
A zoologist is investigating a population of squirrels whose coat color is controlled by a single gene whose two alleles (B1 & B2) are codominant. B1B1 individuals are black, B1B2 individuals are brown, and B2B2 are tan.
She surveys the population and finds 126 black squirrels, 238 brown squirrels, and 49 tan squirrels.
Question: Is this population in HWE? If not, what might explain this pattern? Please show your work.