Sphenisciformes

[sfə‚nis·ə′fȯr‚mēz] (vertebrate zoology) The penguins, an order of aquatic birds found only in the Southern Hemisphere and characterized by paddlelike wings, erect posture, and scalelike feathers.

Sphenisciformes

(penguins), an order of birds. The body ranges in length from 40 (Galápagos penguin) to 120 cm (emperor penguin); the weight is from 3 to 42 kg. The short, dense plumage covers the body evenly. The back is black or blue-black, and the underparts are white. Some species have yellow spots or plumes on the head. The pectoralis and sternum are well developed. The wings, which are flipperlike and covered with scaly feathers, are used as paddles when the penguin swims or dives. The webbed feet and short tail serve as rudders. Sometimes penguins leap out of the water like dolphins as they swim. They emerge from the water onto the shore or ice with a hop. On dry land they walk or, less commonly, run; on ice they slide on their bellies, propelling themselves with their feet and flippers.

There are six genera of penguins, embracing 17 species. The birds are distributed along the coasts of Antarctica, on subantarctic islands, and along the southern coasts of Australia, Africa, and South America. Along the western coast of South America, penguins are found northward to the Galápagos Islands. The birds nest along the shore in colonies of up to 1 million individuals; some species settle in small groups or singly. The nests are on rocks or pebbles; some are constructed under tree roots or in caves. The emperor penguin (Aptenodytes forsteri) reproduces on the ice, with the male holding the single egg on his feet blanketed by a skin fold of the belly. The incubation period is 65 days. The male and female penguins of the genus Pygoscelis take turns incubating the eggs for about 35 days. The chicks are born sighted and covered with a thick fur. The young birds of some species crowd together in groups for protection from the cold when the parents search for food. Penguins feed on fish, cephalopod mollusks, and crustaceans.

REFERENCES

Zhizn’zhivotnykh, vol. 5. Moscow, 1970.
Berndt, R., and W. Meise. Naturgeschichte der Vögel, vols. 1–2. Stuttgart, 1959–62.
A New Dictionary of Birds. Edited by A. L. Thomson. London, 1964.

A. I. IVANOV

Sphenisciformes

Sphenisciformes