[en] Bite force is often associated with specific morphological features, such as sagittal crests. The presence of a pronounced sagittal crest in some tapirs (Perissodactyla: Tapiridae) was recently shown to be negatively correlated with hard-object feeding, in contrast with similar cranial structures in carnivorans. The aim of this study was to investigate bite forces and sagittal crest heights across a wide range of modern and extinct tapirs and apply a comparative investigation to establish whether these features are correlated across a broad phylogenetic scope. We examined a sample of 71 specimens representing 15 tapir species (5 extant, 10 extinct) using the dry-skull method, linear measurements of cranial features, phylogenetic reconstruction, and comparative analyses. Tapirs were found to exhibit variation in bite force and sagittal crest height across their phylogeny and between different biogeographical realms, with high-crested morphologies occurring mostly in Neotropical species. The highest bite forces within tapirs appear to be driven by estimates for the masseter-pterygoid muscle complex, rather than predicted forces for the temporalis muscle. Our results demonstrate that relative sagittal crest height is poorly correlated with relative cranial bite force, suggesting high force application is not a driver for pronounced sagittal crests in this sample. The divergent biomechanical capabilities of different contemporaneous tapirids may have allowed multiple species to occupy overlapping territories and partition resources to avoid excess competition. Bite forces in tapirs peak in Pleistocene species, independent of body size, suggesting possible dietary shifts as a potential result of climatic changes during this epoch.
Disciplines :
Zoology
Author, co-author :
Van Linden, Lisa ; Functional Morphology Lab, Department of Biology, Campus Drie Eiken, Universiteit Antwerpen, Antwerpen, Belgium
Stoops, Kim; Functional Morphology Lab, Department of Biology, Campus Drie Eiken, Universiteit Antwerpen, Antwerpen, Belgium
Dumbá, Larissa C C S ; Departamento de Zoologia, Instituto de Ciências Biológicas, Universidade Federal de Minas Gerais, Minas Gerais, Brazil
Cozzuol, Mario A ; Departamento de Zoologia, Instituto de Ciências Biológicas, Universidade Federal de Minas Gerais, Minas Gerais, Brazil
Maclaren, James ; Université de Liège - ULiège > Département de géologie > Evolution and diversity dynamics lab ; Functional Morphology Lab, Department of Biology, Campus Drie Eiken, Universiteit Antwerpen, Antwerpen, Belgium
Language :
English
Title :
Sagittal crest morphology decoupled from relative bite performance in Pleistocene tapirs (Perissodactyla: Tapiridae).
The authors wish to thank C. Cartelle (Museu de Ciências Naturais PUC Minas), L. F. B. Flamarion (Coleção de Mastozoologia do Museu Nacional do Rio de Janeiro), F. A. Perini (Coleção de Mastozoologia da Universidade Federal de Minas Gerais), O. Pauwels (Royal Belgian Institute of Natural Sciences), J. Lésur (Museum National d'Histoire Naturelle), L. Tyteca (MuseOs Natuurhistorichmuseum), and R. C. Hulbert Jr. (Florida Museum of Natural History) for the access to tapir collections. This study was conceived by JAM. Measurements were collected by LVL, KS, and JAM; first‐hand images were provided by LCCSD, MAC, and JAM. Statistical analyses were performed by LVL; drafts were written by LVL and KS, with all authors contributing to the final version of the manuscript. This work was facilitated by doctoral and post‐doctoral funding awarded to JAM (doctoral by the Fonds Wetenschappelijk Onzerzoek [FWO]; post‐doctoral by Fonds de la Recherche Scientifique [FNRS]; travel grant from the Florida Museum of Natural History [FLMNH]), and a doctoral fellowship awarded to LCCSD (by the Coordenação de Aperfeiçoamento de Pessoal de Nível Superior [CAPES]).The authors wish to thank C. Cartelle (Museu de Ciências Naturais PUC Minas), L. F. B. Flamarion (Coleção de Mastozoologia do Museu Nacional do Rio de Janeiro), F. A. Perini (Coleção de Mastozoologia da Universidade Federal de Minas Gerais), O. Pauwels (Royal Belgian Institute of Natural Sciences), J. Lésur (Museum National d'Histoire Naturelle), L. Tyteca (MuseOs Natuurhistorichmuseum), and R. C. Hulbert Jr. (Florida Museum of Natural History) for the access to tapir collections. This study was conceived by JAM. Measurements were collected by LVL, KS, and JAM; first-hand images were provided by LCCSD, MAC, and JAM. Statistical analyses were performed by LVL; drafts were written by LVL and KS, with all authors contributing to the final version of the manuscript. This work was facilitated by doctoral and post-doctoral funding awarded to JAM (doctoral by the Fonds Wetenschappelijk Onzerzoek [FWO]; post-doctoral by Fonds de la Recherche Scientifique [FNRS]; travel grant from the Florida Museum of Natural History [FLMNH]), and a doctoral fellowship awarded to LCCSD (by the Coordenação de Aperfeiçoamento de Pessoal de Nível Superior [CAPES]).
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