Longevity and life history of cave bears – a review and novel data from tooth cementum and relative emergence of permanent dentition

Abstract

Longevity and other life history variables are key to understanding evolutionary processes and the biology of extinct animals. For the past 20 years, the lifespan of cave bears received an increased interest. Studies focusing on incremental lines of tooth cementum resulted in detailed mortality patterns from different localities. In this review, we summarise literature on age estimation as well as mortality of different European cave bear localities and present novel data on longevity from 94 teeth originating from 20 European localities. Additionally, the relative tooth emergence pattern of the permanent dentition is investigated under the Schultz’s rule framework of possible life history implications. For this, the known sequences of extant bear species are compared with the one of cave bears. Our results suggest that the typical duration of the life of cave bears was 19 years but data from literature show that in rare cases ages of up to 30–32 years were achieved. Additionally, we present the oldest known age for the Middle Pleistocene cave bear Ursus deningeri, 29 years. The tooth eruption pattern of cave bears exhibits a heterochronic shift that implies, under the assumption of Schulz’ rule, a slightly faster life history than closely related species.

Keywords:

• Incremental lines
• age estimation
• Schultz’s rule
• heterochrony
• Ursus spelaeus

Acknowledgements

First, we want to thank Anneke H. van Heteren and Borja Figueirido for inviting us to participate in this special issue. We thank Christine Argot (MNHN), Björn Berning (BZL), Toni Bürgin (NMSG), Stephanie Fassl (PIUW), Christine Frischauf (PIUW), Ursula B. Göhlich (NHM), Oliver Hampe (MfN), Brigitte Hilpert (IPUE), Gernot Rabeder (PIUW), Gertrud Rössner (BSPG), Thomas Schossleitner (MfN), Martin Studeny (BZL), Evangelia Tsoukala (AUTH), and Ingmar Werneburg (GPIT) for providing material for this study. We also want to thank Madeleine Geiger, Evangelia Tsoukala, Borja Figueirido and one anonymous reviewer for their helpful comments on earlier versions of the manuscript.