Morphofunctional aspects of the trophic specialization of the frugivorous green broadbill Calyptomena viridis (Passeriformes, Eurylaimidae): A comparative analysis

Abstract

Morphofunctional analysis of the jaw apparatus of the Green Broadbill (Calyptomena viridis), a member of the archaic family Eurylaimidae (suboscine passerines of the Old World), has uncovered their deep adaptation to consumption of various fruits. This adaptation developed owing to the specific jaw apparatus features of the broadbills fit to swallowing of relatively large food objects of animal origin. In terms of a fruit� eating specialization, all major specific morphological features of the Green Broadbill jaw apparatus have been interpreted from a biomechanical standpoint, including an unusual shape of the jugale, the structure of the jaw joint, the shape and orientation of the quadratum, the ligamentum jugomandibulare externum with its low angle in the transverse plane, the specific attachment of the ligamentum postorbitale, the role of the lacrimale, and the mandibula structure.