Superorder Penguins. They can dive and swim well, but they cannot fly. The front limbs are flippers. Thick and flexible neck, strong and sharp beak, thick plumage, vertical awkward movement. Distributed in colder parts of the Southern Hemisphere.
Superorder Ostrich. They cannot fly, the front limbs are poorly developed, and the hind limbs are long and strong, which help to run quickly. It feeds on plants, as well as insects, lizards and small animals.
Superorder Typical birds. The structure is well adapted to flight, habitat and adapted to life in the forest. The bones are lightweight, with air cavities, there is a keel on the sternum. Nestlings are nesting or brood.
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