Birds are a group of warm-blooded vertebrates constituting the class Aves, characterized 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.
Class: Aves; Linnaeus, 1758
Many of the bones in a bird’s body are hollow, making the bird lightweight and better adapted to flying. Birds also have feathers that make flight easier. Long feathers on the wings and tail help birds balance and steer and other feathers provide insulation and protect birds from the sun’s ultraviolet rays.
The digestive order is as follows: bill, mouth, tongue, pharynx, esophagus, crop, proventriculus, gizzard, small intestine, caeca, rectum, cloaca. shapes and are used for scooping, pecking, tearing and generally picking up the bird’s food.