Geese. A goose is a bird of any of several waterfowl species in the family Anatidae.
   This group comprises the genera Anser, Branta, and Chen, the latter being commonly placed within the genus Anser. Some other birds, mostly related to the shelducks, have goose as part of their names.
   More distantly related members of the family Anatidae are swans, most of which are larger than true geese, and ducks, which are smaller. The term goose is more properly used for a female bird, while gander refers specifically to a male one.
   Young birds before fledging are called goslings. The collective noun for a group of geese on the ground is a gaggle; when in flight, they are called a skein, a team, or a wedge; when flying close together, they are called a plump.
   The word goose is a direct descendant of Proto-Indo-European root, ghans-. The three living genera of true geese are: Anser, grey geese, including the greylag goose, and domestic geese; Chen, white geese, such as the snow goose; and Branta, black geese, such as the Canada goose. Two genera of geese are only tentatively placed in the Anserinae; they may belong to the shelducks or form a subfamily on their own: Cereopsis, the Cape Barren goose, and Cnemiornis, the prehistoric New Zealand goose. Either these or, more probably, the goose-like Coscoroba swan is the closest living relative of the true geese. Fossils of true geese are hard to assign
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