The broadbills are a family of small passerinebirdspecies found in tropical southeast Asia, with a few species in Africa.
Broadbills are brightly coloured birds of wet forest canopies, which feed on fruit and insects. Despite their colours, the habitat makes them difficult to observe. They take insects in flycatcher fashion, snapping their broadbills.
Their nest is a purse-shaped structure built in a tree, into which typically 2–3 eggs are laid.
The Smithornis and Pseudocalyptomena species occur in tropical Africa, the rest extend from the eastern Himalayas to Sumatra and Borneo.
The large size of the hallux and its claw may be func- tionally related to the degree of independent action permitted the hallux in passerines (ex- cept Eurylaimidae) by the absence of a con- nection between their major flexors.
The problem of the Eurylaimidae would dis- appear if the presence of the vinculum in that group could be considered a derived (second- arily primitive) condition.
The absence of this connection (except in the Eurylaimidae, which have a feeble vin- culum) presumably allows independent flexion of the forward toes and of the hallux, which may aid in the versatility of movement in ad- justing the foot to perches of varying sizes and shapes.
These data are analyzed in combi- nation with hindlimb myology and other mor- phological characters described by Raikow (1987), and then this phylogenetic hypothesis is used as a historical framework for investi- gating the biogeography and evolutionary ecol- ogy of the broadbills and asities.
Continued recognition of the Eurylaimidae as separate from the Philepittidae would require acceptance of an ahistorical, paraphyletic group--the broadbills--that can only be char- acterized arbitrarily by the absence of the de- rived features that diagnose the monophyletic asities.
A phylogenetic classification of the broadbills and asities is proposed in which all broadbills and asities are placed in five subfamilies of the Eurylaimidae, and the separate family Philepittidae is abandoned.
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