1. CLASS AVES BY MRS OZEMOKA H.J.
CLASS AVES by MRS OZEMOKA H.J. is licensed under a Creative Commons Attribution-NonCommercial-ShareAlike 4.0 International License

2. 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.

3. 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)

4. 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).

5. CLASSIFICATION The class is divided into two super order namely:
Paleognathae
Neognathae.

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

7. 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
Super order: Neognathae

8. 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