Capitonidae - Systematics, Taxonomy, and Evolution

Systematics, Taxonomy, and Evolution

Fossil American barbets have been found dating from the Miocene in Florida. It is widely agreed that the closest relatives of the barbets are the toucans, and that these two families are also closely related to the honeyguides and woodpeckers (with which they form the order Piciformes).

Formerly the barbets have been treated as one family. However, this has turned out to be paraphyletic with regard to toucans; thus only the American true barbets are retained in the Capitonidae. The African barbets (Lybiidae) and the Asian barbets (Megalaimidae) as well as the two toucan-barbets from the Americas (Semnornithidae) are currently split from this family. Alternatively, the toucans, which evolved from a common ancestor shared with the American barbets, might be included in the traditional all-encompassing barbet family. As they have evolved a suite of characteristics that are unique to themselves they are usually treated separately, and thus the barbets are split up according to the four lineages.