title: The head of the finch: the anatomy of the feeding system in two species of finches (Geospiza fortis and Padda oryzivora).
abstract: Despite the large number of studies devoted to the evolution of beak shape in Darwin's finches, surprisingly little is known about the morphology of the skull and jaw musculature in these birds. Moreover, it remains currently unclear whether Darwin's finches are unusual in their cranial morphology compared with other seed-cracking birds. Here, we provide a detailed description of the morphology of the cranial system in the medium ground finch (Geospiza fortis) and compare it with that of another seed-cracking bird of similar overall size and appearance, the Java finch (Padda oryzivora). Our data show an overall similarity in beak size and cranial morphology. Yet, differences in the jaw adductor size and corresponding attachments to the cranium and mandible are prominent, with the medium ground finch having much more robust jaw-closing muscles. This is reflected in differences in bite forces, with the medium ground finch biting much harder than the Java finch. These data suggest similarities in the evolution of the feeding system in birds specializing in the cracking of hard seeds, but also show the uniqueness of the cranial morphology and bite force of the medium ground finch compared with other seed-cracking birds.
authors: Laboratory of Biomedical Physics, University of Antwerp, Antwerpen, Belgium. annelies.genbrugge@ugent.be
authors: Annelies
authors: A
authors: Genbrugge
authors: Anthony
authors: A
authors: Herrel
authors: Matthieu
authors: M
authors: Boone
authors: Luc
authors: L
authors: Van Hoorebeke
authors: Jeffrey
authors: J
authors: Podos
authors: Joris
authors: J
authors: Dirckx
authors: Peter
authors: P
authors: Aerts
authors: Adriaens
authors: A
authors: Dominique
mesh_terms: D000704:Analysis of Variance; D000818:Animals; D001502:Beak / Q000033:anatomy & histology* / Q000502:physiology; D001696:Biomechanical Phenomena; D001732:Bite Force; D046369:Finches / Q000033:anatomy & histology* / Q000502:physiology; D006257:Head / Q000033:anatomy & histology*; D008410:Masticatory Muscles / Q000502:physiology; D012886:Skull / Q000033:anatomy & histology*; D013045:Species Specificity