The life cycle of the fruit fly Drosophila Some insect groups (e.g. ants, bees, wasps, butterflies, beetles, fleas, mosquitos, flies) are holometabolous ("holo" is Greek for "complete"), meaning they have a pupal stage in which the maggot undergoes a complete transformation (called metamorphosis) into the adult life form. Some other insect groups (e.g. cockroaches, grasshoppers or dragon flies) are hemimetabolous ("hemi", is Greek for "half" or "incomplete"), meaning the larval nymph stage undergoes a stepwise (with each moult) transformation into the adult body shape, where the last moult brings the wings and reproductive organs.

Further resources and reading https://droso4schools.wordpress.com/why-fly/#Movies - Two YouTube movies: the origins and importance of fly research (part 1 - "Why the fly?"), how research in flies can help to understand disease and find potential treatments (part 2 - "Making research fly")   https://droso4schools.wordpress.com - The droso4schools website: the "Why fly?" page explains the advantages of Drosophila in research; the "Organs" page compares tissues and organs of flies and humans with helpful overview images; other tabs on this site provide curriculum-relevant biology sample lessons, as well as information on alcohol, neurodegeneration in humans and flies; and statistics, designed to support these lessons for revision and homework tasks. http://www.flyfacility.ls.manchester.ac.uk/forthepublic - Manchester Fly Facility site: general information for the public and school teachers the "Why the fly?" tab complements the information on droso4schools, providing simple facts, non-specialist books and over 80 lay articles about fly research; the "Outreach Resources" page provides many exciting links to Drosophila-specific information and resources.