Flightless bird also included here. Flightless bird Flightless birds are birds that through evolution lost the ability to fly. There are over 60 extant species including the well known ratites (ostrich, emu, cassowary, rhea and kiwi) and penguins. The smallest flightless bird is the Inaccessible Island rail (length 12.5 cm, weight 34.7 g). The largest (both heaviest and tallest) flightless bird, which is also the largest living bird, is the ostrich (2.7 m, 156 kg). Ostriches are farmed for their decorative feathers, meat and their skins, which are used to make leather. Many domesticated birds, such as the domestic chicken and domestic
Flightless fruit fly as convenient feeders for a variety of companion animals and even as test subjects in aeronautical research Flightless fruit fly Flightless fruit flies (Order Diptera) encompasses a variety of different species of fly, such as "Drosophila melanogaster", "Bactrocera cucurbitae", "Bactrocera dorsalis", and "Drosophila hydei", with genetic mutations that cause them to be flightless. These genetic mutations may have different results such as the development of muscles that cannot support flight or even result in the lack of wings entirely. Flightless fly models have been especially useful for the study of human neuromuscular diseases such as spinal muscular atrophy, spinobulbar muscular