Chordate Zoology - Textbook - I. V. Tsaryk - 2013

Chapter 5. SUPERCLASS TETRAPODS (TERRESTRIAL VERTEBRATES) TETRAPODA, seu QUADRIPEDA.

ANAMNIOTS (ANAMNIA) AND AMNIOTES (AMNIOTA)

5.3. CLASS BIRDS AVES

5.3.3. Systematics and characteristics of representatives of the main orders of the class Aves

5.3.3.2. Superorder Typical, or Neognathous Birds Neognathae

5.3.3.2.7. Order Grebes Podicipediformes

Waterbirds distributed across Water bodies almost worldwide. A total of 20 (19) species. Each toe of these birds has a wide Skin lobe and ends in a flat nail. Plumage is very dense. They do not walk on land. They are excellent swimmers and divers. Flight is direct. They feed on aquatic invertebrates, small fish, and amphibians. They build floating nests in reed beds. The female lays 4–6 eggs, which are incubated by both parents. The chicks are covered in dense down with a striped pattern; they swim with their parents, rest on their parents' backs or under their wings, and begin an independent life at the age of 5–6 weeks, once they are capable of flight. A typical representative is the great crested grebe Podiceps cristatus (Fig. 5.45, 8).