Kingdom: Animalia
Phylum: Chordata
Class: Aves (Birds)

Birds are two legged, warm-blooded, vertebrates which have numerous adaptations that enable the aerial lifestyle that is common to most species. Birds are characterised by feathers which provide insulation and enable flight, a beak with no teeth, and a lightweight but strong skeleton with a furcula, commonly known as the wishbone, located in the bird's chest. The main function of the furcula is to strengthen the thoracic skeleton to assist with flight. Wings are modified forelimbs, and most bird species can fly. Birds lay hard shelled eggs, usually in a nest, that are incubated by the parents. Most juvenile birds have an extended period of parental care after hatching. Around 10,000 living species of birds inhabit ecosystems worldwide in climates from tropical rain forests to the frozen Arctic and Antarctica.