; class Aves, order Anseriformes)
A family of black or grey, short-necked, fairly long-legged, ungainly birds in which the bill is chicken-like, the toes are long and semipalmate, the wings broad with a spur on the leading edge. There are subcutaneous air sacs. The ribs lack uncinate processes. These birds are found in marshy habitats where they wade or swim. They are vegetarian and nest on the ground near water. There are two genera, with three species, found in tropical and subtropical S. America.
Subjects: Zoology and Animal Sciences.