Systematics Anatidae

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anatidae: eurasian teal (anas crecca), gadwall (anas strepera), northern pintail (anas acuta), mallard (anas platyrhynchos), greater scaup (aythya marila), long-tailed duck (clangula hyemalis), northern shoveler (anas clypeata), garganey (anas querquedula), eurasian wigeon (anas penelope), ferruginous duck (aythya nyroca), common goldeneye (bucephala clangula), common merganser (mergus merganser), smew (mergellus albellus), tufted duck (aythya fuligula), red-breasted merganser (mergus serrator), common pochard (aythya ferina). post of belarus, 1996.


the family anatidae introduced english zoologist william elford leach in guide contents of british museum published in 1820. while status of anatidae family straightforward, , species belong little debated, relationships of different tribes , subfamilies within poorly understood. listing in box @ right should regarded 1 of several possible ways of organising many species within anatidae; see discussion in next section.


the systematics of anatidae in state of flux. divided 6 subfamilies, study of anatomical characters livezey suggests anatidae better treated in 9 subfamilies. classification popular in late 1980s 1990s. mtdna sequence analyses indicate, example, dabbling , diving ducks not belong in same subfamily.


while shortcomings occur in livezey s analysis, mtdna unreliable source phylogenetic information in many waterfowl (especially dabbling ducks) due ability produce fertile hybrids, in rare cases possibly beyond level of genus (see example barbary duck ). because sample size of many molecular studies available date small, mtdna results must considered caution.


while comprehensive review of anatidae unites evidence robust phylogeny still lacking, reasons confusing data @ least clear: demonstrated late cretaceous fossil vegavis iaai — modern waterbird belonged extinct lineage—the anatidae ancient group among modern birds. earliest direct ancestors, though not documented fossils yet, likewise can assumed have been contemporaries dinosaurs. long period of evolution , shifts 1 kind of waterbird lifestyle have obscured many plesiomorphies, while apomorphies apparently quite result of parallel evolution, example non-diving duck type displayed such unrelated genera dendrocygna, amazonetta, , cairina. fossil record, see below.


alternatively, anatidae may considered consist of 3 subfamilies (ducks, geese, , swans, essentially) contain groups presented here tribes, swans separated subfamily cygninae, goose subfamily anserinae containing whistling ducks, , anatinae containing other clades.








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