Relation between morphology and dietary traits in horse jugal upper teeth during the middle pleistocene in Southern France

Abstract

The morphometric adaptations and the phyletic evolution of the Equus genus during the Quaternary are still the focus of many studies. Several forms (species/subspecies) of Middle and Upper Pleistocene horses have been described in Europe but their spatio-temporal variations, in relation to the environment and the climate require further clarification. This is the case in particular for a typical Middle Pleistocene form: Equus mosbachensis ssp. In this paper, we present combined morphological and ecometric observations based on the upper teeth from three subspecies of this form from five sites: Camps-de-Peyre (E. m. campdepeyri), La Micoque (E. m. micoquii), Lunel-Viel I and Lunel-Viel IV (Equus m. palustris) and Igue des Rameaux (E. mosbachensis ssp.). The understanding of the specific characteristics of this taxon should enable us to better define the occupied habitat and environment. This preliminary study shows the importance of the adaptive capacities of Equus mosbachensis and the pertinence of combined paleontological and ecometric studies for enhancing our understanding of the ecology and the evolution of fossil ungulates. In addition, some authors have postulated that the length of the protocone is correlated to a diet with a high grass content. Although this tendency may have existed during the Quaternary, our study shows, on a smaller chronological scale, that there is no correlation between this measurement and horse diet and paleoenvironment.