The puffbirds and their relatives in the near passerine family Bucconidae are tropical tree-dwelling insectivorous birds that are found from South America up to Mexico. Together with their closest relatives, the jacamars, they form a divergent lineage within the order Piciformes, though the two families are sometimes elevated to a separate order Galbuliformes. Lacking the iridescent colours of the jacamars, puffbirds are mainly brown, rufous or grey, with large heads, large eyes, and flattened bills with a hooked tip. Their loose, abundant plumage and short tails makes them look stout and puffy, giving rise to the English name of the family. The species range in size from the rufous-capped nunlet, at 13 cm (5.1 in) and 14 g (0.49 oz), to the white-necked puffbird, at up to 29 cm (11 in) and 106 g (3.7 oz).