Table of Contents Author Guidelines Submit a Manuscript
BioMed Research International
Volume 2014, Article ID 406507, 11 pages
Research Article

On the Relationships of Postcanine Tooth Size with Dietary Quality and Brain Volume in Primates: Implications for Hominin Evolution

1Departamento de Prehistoria y Arqueología, Facultad de Filosofía y Letras, Campus de Cartuja S/N, 18071 Granada, Spain
2Edificio Centro de Documentación Científica, Instituto Universitario de la Paz y los Conflictos, Universidad de Granada, C/Rector López Argüeta, 10871 Granada, Spain
3Anthropological Institute & Museum, University of Zürich, Winterthurerstrasse 190, 8057 Zürich, Switzerland
4Departamento de Ecología y Geología (Área de Paleontología), Facultad de Ciencias, Campus Universitario de Teatinos, 29071 Málaga, Spain
5Departamento de Biología Molecular y Bioquímica, Facultad de Ciencias, Campus Universitario de Teatinos, 29071 Málaga, Spain

Received 30 April 2013; Revised 15 December 2013; Accepted 16 December 2013; Published 30 January 2014

Academic Editor: Stephen E. Alway

Copyright © 2014 Juan Manuel Jiménez-Arenas et al. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.


Brain volume and cheek-tooth size have traditionally been considered as two traits that show opposite evolutionary trends during the evolution of Homo. As a result, differences in encephalization and molarization among hominins tend to be interpreted in paleobiological grounds, because both traits were presumably linked to the dietary quality of extinct species. Here we show that there is an essential difference between the genus Homo and the living primate species, because postcanine tooth size and brain volume are related to negative allometry in primates and show an inverse relationship in Homo. However, when size effects are removed, the negative relationship between encephalization and molarization holds only for platyrrhines and the genus Homo. In addition, there is no general trend for the relationship between postcanine tooth size and dietary quality among the living primates. If size and phylogeny effects are both removed, this relationship vanishes in many taxonomic groups. As a result, the suggestion that the presence of well-developed postcanine teeth in extinct hominins should be indicative of a poor-quality diet cannot be generalized to all extant and extinct primates.