What is a Bird?
Definition of BIRD
1 : archaic: the young of a feathered vertebrate. 2 : any of a class (Aves) of warm-blooded vertebrates distinguished by having the body more less completely covered with feathers and the forelimbs modified as wings.
Citron Crested Cockatoo Emu
Birds are classified as feathered, winged, two-legged, warm-blooded, egg-laying vertebrates and are characterized by feathers, a beak with no teeth and the laying of hard-shelled eggs. (Source : Wikipedia).
There are around 9,700 species of birds in the world. They vary in size from the ostrich at 8 feet tall, down to the Bumblebee Hummingbird 2.75 inches in length. Birds can be found on all seven continents and in every habitat from the Sahara Desert to the frozen Antarctic Tundra.