Introduction
D.melanogaster a fruitfly which is very famous among biologists. its great importance attracted many scientists
around the world to find out more about it. Drosophila is a genus of small flies, belonging to the family Drosophilidae, whose members are often called “fruit flies”. One species of Drosophila in particular D.melanogaster has been heavily used in research in genetics and is a common model organism in developmental biology. The entire genus, however, contains about 1,500 species and is very diverse in appearance, behavior, and breeding habitat. Scientists who study Drosophila attribute the species’ diversity to its ability to be competitive in almost every habitat, including deserts. D.melanogaster came into the scene in 1909 decades before bacteria and fungi, when Thomaos Hunt Morgan found sex linked inheritance gene on the chromosome of D.melanogaster with the help of genetic crosses only. Further his student Alfred Strutevant made first genetic linkage map whose ccorrectness cannot be challenge even with high throughput techniques available now. The general principles of gene transmission, linkage, sex determination, genetic interactions; molecular, biochemical and developmental genetics, chromosomal aberrations, penetrance and expressivity, and evolutionary change may all be admirably demonstrated by using the fruit fly.
