Birds are a group of warm-blooded vertebrates constituting the class Aves (Latin:), characterised by feathers, toothless beaked jaws, the laying of hard-shelled eggs, a high metabolic rate, a four-chambered heart, and a strong yet lightweight skeleton.Birds live worldwide and range in size from the 5.5 cm (2.2 in) bee hummingbird to the 2.8 m (9 ft 2 in) common ostrich.

The California condor (Gymnogyps californianus) is a New World vulture and the largest North American land bird. It became extinct in the wild in 1987 when all remaining wild individuals were captured, but has since been reintroduced to northern Arizona and southern Utah (including the Grand Canyon area and Zion National Park), the coastal mountains of California, and northern Baja California ...