Duck

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Ducks
Scientific classification
Kingdom:Animalia
Phylum:Chordata
Class:Aves
Order:Anseriformes
Family:Anatidae
Subfamilies

Dendrocygninae
Oxyurinae
Anatinae
Merginae

Duck is the common name for a number of types of bird in the family Anatidae. Ducks are mostly aquatic birds, smaller than their relatives the swans or geese, found in both fresh and salt water. Ducks exploit a variety of food sources such as grasses, grains and water plants, fish, insects, and the like.

The males (drakes) of northern species often have showy plumage, but this is moulted in summer to give a more female-like appearance, the "eclipse" plumage.

Ducks have many domestic uses, being farmed for their meat, eggs, and feathers and down. In particular, eiderdown is notable for being shed by wild eider ducks rather than being plucked.

The Anatidae subfamilies typically considered as ducks are listed below. Some members of the shelduck group Tadorninae are also named as ducks. See that article and Anatidae.

The duck groups are:

  • Dendrocygninae: the whistling ducks. There are 9 species in the genus Dendrocygna which has a worldwide distribution through the tropics and subtropics, and a single diving species, Thalassornis leuconotus the White-backed Duck of Africa, which is difficult to classify and has often been placed in the Oxyurinae (which it resembles in morphology and feeding habits). It appears that the similarity is largely a matter of convergence, however.
  • Anatinae: perching, diving, and dabbling ducks. The Anatinae are further divided into three groups:
    • There are 19 species of perching duck in 15 genera (though the similarities in some are now regarded as convergent, which suggests that a reassignment may be appropriate).
    • About 40 species of dabbling duck in 2 genera: the monotypic Marmaronetta (Marbled Teal) may instead be numbered among the pochards. The remaining 40-odd species are all part of the genus Anas, which includes wigeons, gadwalls, the true teals, pintails, mallards, and shovelers.
    • The 16 species of pochards or diving ducks in 3 genera: Netta (3 species), Aythya (12 species), and Rhodonessa (the recently extinct Pink-headed Duck of India).

The Anseriformes and the Galliformes ( pheasants etc) are basal to neognathous birds, and should follow ratites and tinamous in bird classification systems. See the chart below

Image:Galloanseri2.png

For further taxonomic comments, see also Sibley-Ahlquist taxonomy.

Some species of duck, mainly those breeding in the temperate and arctic northern hemisphere, are migratory, but others are not. It is during times of migration that ducks are sometimes hunted.

Ducks should not be confused with several types of unrelated birds with similar forms, such as loons or divers, grebes, gallinules, and coots.

See also


Fictional, anthropomorphized ducks:

References

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