The first subfamily and tribe of the Anatidae consists of the single genus and species Anseranas semipalmata, or magpie goose. This species deviates in almost every respect from the rest of the Anatidae, and anatomical evidence indicates that it has some affinities with the South American family of screamers, the Anhimidae (Delacour, 1954; Woolfenden, 1961). The screamers are a group of semiterrestrial birds which in turn have some of the characteristics of gallinaceous birds. It appears that the screamers and the magpie goose represent major stages in the evolution of the typical waterfowl from a gallinaceous ancestor. Besides the numerous anatomical similarities between the magpie goose and the screamers, a few other, obvious similarities are of interest.
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