title: Chewing on the trees: Constraints and adaptation in the evolution of the primate mandible.
abstract: Chewing on different food types is a demanding biological function. The classic assumption in studying the shape of feeding apparatuses is that animals are what they eat, meaning that adaptation to different food items accounts for most of their interspecific variation. Yet, a growing body of evidence points against this concept. We use the primate mandible as a model structure to investigate the complex interplay among shape, size, diet, and phylogeny. We find a weak but significant impact of diet on mandible shape variation in primates as a whole but not in anthropoids and catarrhines as tested in isolation. These clades mainly exhibit allometric shape changes, which are unrelated to diet. Diet is an important factor in the diversification of strepsirrhines and platyrrhines and a phylogenetic signal is detected in all primate clades. Peaks in morphological disparity occur during the Oligocene (between 37 and 25 Ma) supporting the notion that an adaptive radiation characterized the evolution of South American monkeys. In all primate clades, the evolution of mandible size is faster than its shape pointing to a strong effect of allometry on ecomorphological diversification in this group.
authors.affiliation: Research Centre in Evolutionary Anthropology and Palaeoecology, School of Natural Sciences and Psychology, Liverpool John Moores University, James Parsons Building, Byrom Street, Liverpool, L3 3AF, UK. C.meloro@ljmu.ac.uk.
authors.forename: Carlo
authors.initials: C
authors.lastname: Meloro
authors.affiliation: Laboratory of Ecology and Biogeography, Department of Biology, CCNE, Federal University of Santa Maria, Santa Maria, RS, 97110-970, Brazil.
authors.forename: Nilton Carlos
authors.initials: NC
authors.lastname: Cáceres
authors.affiliation: Dipartimento di Scienze della Terra, dell´ Ambiente e delle Risorse, Università degli Studi di Napoli "Federico II,", L.go San Marcellino 10, 80138, Napoli, Italy.
authors.forename: Francesco
authors.initials: F
authors.lastname: Carotenuto
authors.affiliation: Programa de Pós-Graduação em Biodiversidade Animal, Department of Biology, CCNE, Federal University of Santa Maria, Santa Maria, RS, 97110-970, Brazil.
authors.forename: Jonas
authors.initials: J
authors.lastname: Sponchiado
authors.affiliation: Programa de Pós-Graduação em Ecologia e Conservação, CCBS, Federal University of Mato Grosso do Sul, Cx.P. 549, Campo Grande, MS, 79.070-900, Brazil.
authors.forename: Geruza Leal
authors.initials: GL
authors.lastname: Melo
authors.affiliation: Dipartimento di Scienze della Terra, dell´ Ambiente e delle Risorse, Università degli Studi di Napoli "Federico II,", L.go San Marcellino 10, 80138, Napoli, Italy.
authors.forename: Federico
authors.initials: F
authors.lastname: Passaro
authors.affiliation: Dipartimento di Scienze della Terra, dell´ Ambiente e delle Risorse, Università degli Studi di Napoli "Federico II,", L.go San Marcellino 10, 80138, Napoli, Italy.
authors.forename: Pasquale
authors.initials: P
authors.lastname: Raia
mesh_terms: D000818:Animals; D005075:Biological Evolution; D004032:Diet; D005260:Female; D005580:Fossils / Q000033:anatomy & histology; D008297:Male; D008334:Mandible / Q000033:anatomy & histology*; D008409:Mastication; D010802:Phylogeny; D011323:Primates / Q000033:anatomy & histology* / Q000502:physiology; D013045:Species Specificity
keywords: Allometry; diet; disparity; geometric morphometrics; macroevolution; morphology