Heterosis is one of the most important genetics concept in Agricultural practice.Since the use of farm animals to carry out studies on heterosis requires much time, funds and effort, Drosophila melanogaster were therefore utilized and the results obtained applied to farm animals. The study was conducted to measure the amount of heterosis in crosses between geographically separated populations of Drosophila melanogaster. Equations for predicting heterosis by geographic distance was established. This work is important for the concept of breed development. It is an excellent study material for all category of Animal Science students and Animal Scientists.