3. In fruit flies, gene B specifies a bristle phenotype (normal bristles is dominant and mutant bristles is
recessive), and gene R specifies eye color (red eyes is dominant and white eyes is recessive). When a BbRr
individual was crossed to a bbrr individual, the following phenotypic distribution was observed in the offspring:
90 normal bristles with red eyes, 92 mutant bristles with white eyes, 10 normal bristles with white eyes, and 8
mutant bristles with red eyes. When a another BbRr individual was crossed to a bbrr individual, the phenotypic
ratio was different: 45 normal bristles with white eyes, 46 mutant bristles with red eyes, 5 normal bristles with
red eyes, and 4 mutant bristles with white eyes. Explain why the results were different.