Birds.

Abstract

AbstractThis chapter discussed the important differences in the anatomy and physiology of some of the known species of birds, all belonging to the class Aves. The possession of feathers, and in the majority of species the ability to fly, is the reason for their success. Flight allows them to colonize new habitats, find new sources of food and escape predators. Much of their anatomy and physiology has evolved to facilitate life in the air. The most commonly kept species of cage and aviary birds include several members of the order Psittaciformes such as the budgerigar (Melopsittacus undulatus), the cockatiel (Nymphicus hollandicus) and several species of parrot. These birds are brightly coloured and have an ability to mimic sounds, giving rise to their apparent ability to 'talk'. Many species of perching bird from the order Passeriformes are also popular in aviaries. These include finches such as the Zebra Finch (Taeniopygia poephilia guttata) and canaries (Canarius serinus). Highlights of this chapter includes examples of the way in which the bird is adapted for flight, important parts of the avian digestive system (tongue, rectum, crop, beak, gizzard, cloaca, ileum, caecum, duodenum, oesophagus, proventriculus, and large intestine), the functions of the female reproductive system which includes the infundibulum, magnum, isthmus, shell gland, and vagina, and details on the passage of air through the respiratory system of the bird, from inspiration to eventual expiration.