Bite force and body mass of the fossil rodent Telicomys giganteus (Caviomorpha, Dinomyidae)

Abstract

An exceptionally well-preserved skull of the Pliocene rodent Telicomys giganteus allowed the first estimation of body mass and analysis of the bite mechanics of this species of South American giant rodent. In this study, we reconstructed the main anatomical features of the skull of this Pliocene rodent and related them to the bite force at the incisors. The average of an estimation body mass gives 100 kg. We also estimated the bite force using three different techniques. Two methods suggest that bite forces at the incisors have a range of 500–1000 N. However, the incisors seem to be stronger than expected for this bite force, implying that the bite forces may have been greater than 2000 N. We consider the hypothesis of defense against predators or other agonistic behavior to explain our results.

Keywords:

• Giant rodent
• Pliocene
• body mass
• bite force
• incisors

Acknowledgements

We want to express our gratitude to Alejandro Kramarz and Enrique González, who allowed access to the collections under their care. Aldo Iván Vassallo and two anonymous reviewers made significant improvements to the manuscript.