Form a small discussion group and decide on the most likely genetic explanation for each of the following situations;

Cross A performed by Morgan and shown in Figure 3.18 is between a mutant male fruit fly with white eyes and a female fruit fly from a pure-breeding, red-eye stock. The figure shows that 1237 F₁ progeny were produced, all of them with red eyes. In reality, this isn't entirely true. Among the 1237 F₁ progeny were 3 male flies with white eyes. Give two possible explanations for the appearance of these white-eyed males.