The cave bear (Ursus spelaeus) was one of several spectacular megafaunal species that became extinct in northern Eurasia during the late Quaternary. Vast numbers of their remains have been recovered from many cave sites, almost certainly representing animals that died during winter hibernation. On the evidence of skull anatomy and low δ15N values of bone collagen, cave bears appear to have been predominantly vegetarian. The diet probably included substantial high quality herbaceous vegetation. In order to address the reasons for the extinction of the cave bear, we have constructed a chronology using only radiocarbon dates produced directly on cave bear material. The date list is largely drawn from the literature, and as far as possible the dates have been audited (screened) for reliability. We also present new dates from our own research, including results from the Urals. U. spelaeus probably disappeared from the Alps and adjacent areas – currently the only region for which there is fairly good evidence –c. 24 000 radiocarbon years BP (c. 27 800 cal. yr BP), approximately coincident with the start of Greenland Stadial 3 (c. 27 500 cal. yr BP). Climatic cooling and inferred decreased vegetational productivity were probably responsible for its disappearance from this region. We are investigating the possibility that cave bear survived significantly later elsewhere, for example in southern or eastern Europe.

Extinction chronology and palaeobiology of the cave bear (Ursus spelaeus)

The history of stones: behavioural inferences and temporal resolution of an archaeological assemblage from the Middle Palaeolithic

Relative warp analyses of landmarks describing cranial and mandibular shape are used for investigating patterns of morphological variation among extant bears (Mammalia, Carnivora, Ursidae) indicative of diet and feeding behavior. These patterns are used for deriving inferences about the autecology of two extinct species previously assumed to have had different dietary preferences, the North American giant, short-faced bear Arctodus simus and the Eurasian cave bear Ursus spelaeus. Results reveal a set of shared craniodental traits among the herbivorous bears, including short and vaulted skulls with well-developed zygomatic arches, lateralized orbits and small canines, concave jaws with a highly positioned condyle, large moment arms for the temporalis and masseter muscles, and long cheek teeth. In contrast, those bears that consume animal resources have long skulls with small zygomatic arches, frontalized orbits and well-developed canines, and long jaws with a deep mandibular symphysis, low muscle leverages, a condyle situated at the level of the tooth row and reduced cheek teeth. The craniodental morphology of omnivorous bears is intermediate between those of faunivores and herbivores. This is also the case of the short-faced bear and the cave bear, which suggests that previous reconstructions of the feeding ecology of these extinct species (highly carnivorous for A. simus and herbivorous for U. spelaeus) should be revised.

Ecomorphological correlates of craniodental variation in bears and paleobiological implications for extinct taxa: an approach based on geometric morphometrics

Previous bone collagen carbon and nitrogen isotopic studies of Late Pleistocene European cave bears (Ursus spelaeus) have shown that these bears frequently had low nitrogen isotope values, similar to those of herbivores and indicating either unusual physiology related to hibernation or a herbivorous diet. Isotopic analysis of animal bone from the Pestera cu Oase (Cave with Bones), Romania, shows that most of its cave bears had higher nitrogen isotope values than the associated herbivores and were, therefore, omnivorous. The Oase bears are securely identified as cave bears by both their morphology and DNA sequences. Although many cave bear populations may have behaved like herbivores, the Oase isotopic data demonstrate that cave bears were capable of altering their diets to become omnivores or even carnivores. These data therefore broaden the dietary profile of U. spelaeus and raise questions about the nature of the carnivore guild in Pleistocene Europe.

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Isotopic evidence for omnivory among European cave bears: Late Pleistocene Ursus spelaeus from the Peştera cu Oase, Romania.

Bears and humans in Chauvet Cave (Vallon-Pont-d'Arc, Ardèche, France): Insights from stable isotopes and radiocarbon dating of bone collagen

Deciphering bone depositional sequences in caves through the study of manganese coatings

Sexual dimorphism and ontogenetic variation in the skull of the cave bear ( Ursus spelaeus Rosenmüller) of the European Upper Pleistocene

Le dimorphisme sexuel chez l'ours des cavernes n'affecte pas tous les os du squelette avec la meme intensite et, qui plus est, il y a un degre different de dimorphisme sexuel dans differentes populations. Trois types de pressions selectives influencent le degre de dimorphisme sexuel : choix sexuel, divergence de niche des mâles et des femelles, et differences dans les roles reproducteurs des deux sexes. Cet article traite le dimorphisme des sexes chez les ours des cavernes de deux cavernes du nord-ouest de l'Espagne : l'un d'une phase temperee pendant l'OIS 3 et l'autre d'une phase froide dans l'OIS 2. L'analyse metrique simple a ete executee afin d'examiner les differences globales de la taille entre les sexes. Des donnees des isotopes stables (δ 13C, 8 15N) ont ete employees pour observer les differences de regime alimentaire entre les sexes. Nos resultats prouvent que les divers types de mecanismes conduisant au dimorphisme sexuel habituellement admis pour des mammiferes n'est pas si simple et ne peut seul expliquer le dimorphisme montre par les ours des cavernes. Toutefois nos resultats refletent qu'une pression selective forte affectant une population, comme pendant des periodes froides, exagere la difference entre les sexes alors que dans des periodes temperees, la difference n'est pas aussi marquee.

Fernando López-González

Papers

Deciphering bone depositional sequences in caves through the study of manganese coatings

Sexual dimorphism and ontogenetic variation in the skull of the cave bear ( Ursus spelaeus Rosenmüller) of the European Upper Pleistocene

Palaeobiological implications of the cave bear sex dimorphism

Ordering of a granular layer of cubes under strain-induced shear and vibration