CLASS AVES BY MRS OZEMOKA H J CLASS

CLASS AVES BY MRS OZEMOKA H. J. CLASS AVES by MRS OZEMOKA H. J. is licensed under a Creative Commons Attribution-Non. Commercial-Share. Alike 4. 0 International License

INTRODUCTION �Birds or Aves are the most noticeable, melodious and most beautiful of the vertebrates. �There are more than 10, 400 species world wide. �They are found in the forests, deserts, mountains, praires and all oceans.

CHARACTERISTICS �They are endothermic or warm blooded. �Their forelimbs are modified as wings. �They combine flight with bipedalism i. e two footed locomotion. �They have light bones which support flight and the body framework. �Feathers are a unique feature in birds. �They have scaly legs (lower part of the hind limb)

INTRODUCTION CONTINUES �They have a horny beak, which is a modification of the jaws. �They have no teeth. �They have a four chambered heart. �Their lungs have air pouches for gaseous exchange. �They lack external ear lobe. They possess a large pectoral girdle with a wide sternum which is provided with keel for attachment of flight muscles (except in flightless birds like Ostrich). �Fertilization is internal. �The skull consist of a single occipital condyle (a smallbony knob).

CLASSIFICATION �The class is divided into two super order namely: 1. Paleognathae 2. Neognathae.

Super order Paleognathae �It means ancient jaw. It includes modern birds with ancestral archosaurian palate. Examples include: Ostriches, Cassowaries, kiwis etc.

Super order: Neognathae �They are modern birds with flexible palate. The various orders include: Anseriformes e. g Goose Galliformes e. g Quail, Turkeys, domestic fowl etc. Sphenisciformes e. g Penguins. They have short wings and are marine swimmers. Gaviiformes e. g Loons which are swimmers and diverers. Phoenicopteriformes e. g flamigos

ASSIGNMENT 2 �Write on the different feathers found in birds. Describe them and state their functions. �Write an essay on migration in birds. �Write on the feet and beak modification as it relates to their feeding