Relationship between jaw apparatus, feeding habit, and food source in oriental woodpeckers.

Associations among feeding habit, beak type, and food source in birds have been widely studied and are well known to exist. The relationship between feeding habit and jaw apparatus in birds has not attracted attention from ornithologists, perhaps because of the complexity of the skeletal morphology of the feeding system of birds. The goal of this study was to compare the jaw apparatus and foraging strategies of various Oriental species of the Picidae (Meiglyptini and Picini tribes) using a morphofunctional analysis of the skeletal structure of the jaw apparatus. This study showed that there are at least three types of jaw apparatus in these woodpeckers, as follows: 1) robust, developed, and complex; 2) complexity and development intermediate, as observed in Meiglyptes tristis and Dinopium spp., whose main foraging method involves gleaning, probing, and tapping; and 3) poorly developed, as observed in Picus miniaceus and Hemicircus concretus. The success of woodpeckers as a natural group is due not only to their feeding diversity, but also their ability to explore a wide range of different resources, as appropriate to their jaw apparatus.