The organism typically used as a model organism in genetic engineering studies is the fruit fly, scientifically known as *Drosophila melanogaster*. This species is favored due to its short life cycle, ease of maintenance, and well-mapped genome. Researchers use fruit flies to study developmental processes, genetic inheritance, and the effects of genes on behavior. Their genetic simplicity allows for easier manipulation and observation of genetic traits, making them invaluable in modern genetics research.