iGenetics 3rd Edition by Peter Russell

Exercise 4

In Drosophila, the mutant black ( b ) has a black body, and the wild type has a grey body; the mutant vestigial ( vg ) has wings that are much shorter and crumpled, compared with the long wings of the wild type. In the following cross, the true-breeding parents are listed together with the counts of offspring of F 1 females black and vestigial males:
Use these data to calculate the map distance between the black and vestigial genes.