HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS		QUICK SEARCH:   [advanced] Author: Keyword(s): Year:  Vol:  Page:

This Article Figures Only Full Text Full Text (PDF) Services Email this article to a friend Similar articles in this journal Alert me to new issues of the journal Download to citation manager Google Scholar Articles by HAUTIER, L. Articles by VIANEY-LIAUD, M. GeoRef GeoRef Citation

BIOMECHANICAL CHANGES AND REMODELING OF THE MASTICATORY APPARATUS DURING MAMMALIAN EVOLUTION: THE CASE OF THE ISSIODOROMYINAE (RODENTIA)

¹ 1. Université Montpellier 2, Laboratoire de Paléontologie, Institut des Sciences de l'Evolution de Montpellier, Unité Mixte de Recherche (UMR)–Centre National de la Recherche Scientifique (CNRS) 5554, Cc 064, 2, place Eugène Bataillon, F-34095 Montpellier Cedex 5, France
² 2. Universität Bonn, Steinmann-Institut, Paläontologie, Nussallee 8, 53115 Bonn, Germany

The direction of mastication revealed by dental microwear was studied in relation to changes in the structure of the masticatory apparatus in the Issiodoromyinae (Rodentia, Mammalia). Our results offer a rare opportunity to assess the order of establishment of the morphological characters that are related to the acquisition of propalinal mastication in an extinct lineage. Elfomys and Pseudoltinomys show cuspidate tooth crowns, a high mandibular condyle, and a significant lateromedial orientation of the masticatory muscles (superficial masseter and internal pterygoid) in association with oblique chewing movements. In contrast, the Issiodoromys lineage is characterized by a flat molar occlusal surface, a low mandibular condyle, and posterior orientation of the masseter and pterygoid associated with slightly oblique to propalinal chewing. We show that striking convergences with some members of Ctenohystrica have occurred in the evolution of the Issiodoromyinae.