Puffbirds get their common name from their fluffy plumage. In Spanish, they have been nicknamed
bobo ("dummy") from their propensity to sit motionless waiting for prey. American naturalist
Thomas Horsfield defined the Bucconidae in 1821. The family was classified as part of the Piciformes by
Alexander Wetmore in his work
A Systematic Classification for the Birds of the World (1930, revised in 1951 and 1960). The placement of the combined puffbird and jacamar lineage was in question, with some bone and muscle features suggesting they may be more closely related to the
Coraciiformes. Analysis of
nuclear DNA in a 2003 study placed them as
sister group to the rest of the Piciformes, also showing that the groups had developed
zygodactyl feet (two toes facing forward and two aft) before separating. Per Ericson and colleagues, in analysing
genomic DNA, confirmed that puffbirds and jacamars were sister groups and their place in Piciformes. The lineage is sometimes elevated to order level as Galbuliformes, first proposed by Sibley and Ahlquist in 1990. The
phylogenetic relationship between the puffbirds and the eight other families that make up the order Piciformes is shown in the cladogram below. The number of species in each family is taken from the list maintained by
Frank Gill,
Pamela C. Rasmussen and David Donsker on behalf of the
International Ornithological Committee (IOC). }} Molecular investigation of the Bucconidae in 2004 indicated that the nunlets (genus
Nonnula) diverged from the common ancestor of other puffbirds an estimated 25 million years ago, with the genus
Malacoptila the next to branch off around 19.1 million years ago. A fossil right wing recovered from Lower Eocene beds in Lincoln County, Wyoming, was initially classified as a puffbird and given the name
Primobucco mcgrewi. The discovery of more complete specimens, including twelve in 2010, shows that
Primobucco was instead an early type of
roller. ==Distribution and habitat==