1. You have four strains of Drosophila (1–4) that were isolated from different geographic regions. You compare the banding patterns of the second chromosome and obtain these results (each letter...

1. You have four strains of Drosophila (1–4) that were isolated from different geographic regions. You compare the banding patterns of the second chromosome and obtain these results (each letter corresponds to a band): (1) m n r q p o s t u v (2) m n o p q r s t u v (3) m n r q t s u p o v (4) m n r q t s o p u v If strain (3) is presumed to be the ancestral strain, in what order did the other strains arise?

2. In Drosophila, the recessive white eyes gene is located near the tip of the X chromosome. A wild-type male is irradiated and mated with a white-eyed female. Among the progeny is one red-eyed male. How can you explain the red-eyed male, and how could you test your hypothesis?