New results on ursids from the Early Pleistocene site of Untermassfeld

Abstract

The present study is a revision of the currently available fossil bear remains from the Epivillafranchian locality Untermassfeld (Germany). The authors have made a detailed description and short reappraisal of the taxonomic status of the specimens by comparison with bear material from other localities. The Untermassfeld bears share a number of common features with both modern brown bears, as well as with the Early Pleistocene Ursus etruscus. They differ from U. etruscus in exhibiting reduced number of premolars, as is also the case with U. arctos, with the U. deningeri-spelaeus lineage and with U. dolinensis from Atapuerca (Spain). Only U. etruscus retains the primitive condition with a full set of premolars. The Untermassfeld ursid is similar to the Atapuerca Gran Dolina U. dolinensis in many respects. Both share a number of primitive arctoid-like features, while others link them to the cave bear lineage. For this the Untermassfeld bear is here referred to as Ursus ex gr. U. dolinensis. Untermassfeld provides us with a window into European bears during the Epivillafranchian. They constituted a metapopulation of interconnected subpopulations characterised by a mosaic of primitive and derived traits. These features were differentially inherited in the descendant lineages that finally separated from one another starting sometime from the latest Early Pleistocene through the early Middle Pleistocene, leading to typical brown and cave bears.