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The diet of the extinct European cave bear, Ursus spelaeus, has widely been debated. Diverging from the extant brown bear (Ursus arctos) approximately 1.2 million years ago, the cave bear is one of the most ubiquitous fossil bears occurring in Europe during the Middle and Late Pleistocene. Early morphological studies suggested that the cave bear was likely specialized on processing tough and/or abrasive foods, while later two-dimensional low-magnification microwear studies suggested that they were omnivorous and may have consumed more bone than U. arctos. Here, we used dental microwear texture analysis (DMTA) to further interpret the diet of the cave bear. Microscopic wear features were assessed and compared to modern ursids, including the cave bears' closest living relative, U. arctos. Results suggest that U. spelaeus consumed a diet with a diversity of textural properties, similar to most other bears and only distinguishable from the hyper-carnivorous polar bear (Ursus maritimus). Further, only U. maritimus can be distinguished from all bear species here examined (i.e., the giant panda bear, Ailuropoda melanoleuca; sun-bear, Ursus malayanus; spectacled bear, Tremarctos ornatus; American black bear, Ursus americanus; and U. arctos), with significantly greater area-scale fractal complexity (Asfc) of microwear surfaces. The DMTA of A. melanoleuca also has significantly lower Asfc than T. ornatus and U. americanus, consistent with observed dietary behavior. As modern bears vary their diets seasonally and across their range, it may be difficult to characterize the dietary ecology of extinct bears using dental microwear alone. Nevertheless, DMTA here demonstrates that U. spelaeus had a diet distinct from the hyper-carnivorous U. maritimus and instead likely consumed food with textural properties most similar to other herbivorous/omnivorous bears. Lastly, the European cave bear and North American giant short-faced bear (Arctodus simus) may have had similar diets as evident from DMTA, with U. spelaeus potentially eating tougher food items. [ABSTRACT FROM AUTHOR]

ABSTRACT Insights into causes of extinction in fossil animals can contribute to an understanding of how environmental or anthropogenic processes may affect extant animals. Cave bears that went extinct in the late Pleistocene in Europe have been considered largely herbivorous based on tooth, skull and jaw morphology. Nitrogen and carbon isotopic composition (δ15N, δ13C) of bone collagen of many cave bears having values similar to or lower than those of coeval herbivores support an exclusive plant diet and their occurrence in habitats with denser vegetation. A complicating aspect of this hypothesis is that isotopic compositions of bulk collagen, especially those of nitrogen, could reflect environmental fluctuation as well as behavioural and physiological traits, which are not related to trophic position and so may lead to uncertainty in palaeodietary reconstruction. Here we show that δ15N analysis of individual collagen amino acids of fossil bears from Goyet Cave (Belgium) indicates that cave bears had a constant trophic position of 1.9-2.1, indicating purely herbivorous diets, while brown bears had a trophic position of 2.0-2.4, indicating a slightly more omnivorous diet. Results might support the hypothesis of the extinction of cave bear due to the inflexibility in feeding habits. [ABSTRACT FROM AUTHOR]

The diet of the fossil bear Ursus spelaeus has been debated extensively. U. spelaeus is thought to have been herbivorous, but the exact composition of its diet remains unclear. To test this, the cranial morphology of U. spelaeus was analysed using 3D geometric morphometrics and compared to that of extant Ursidae. An approach including the Ursus species with a varied diet (brown, and American and Asiatic black bears) allows for a more precise focus on food items that are directly relevant to the question of the diet of U. spelaeus . Landmarks for 3D digitisation of the cranium were chosen to reflect functional morphology relating to the attachment of the musculus temporalis and m. masseter and general shape of the cranium. Extant Ursidae and the extinct U. spelaeus were digitised with a Microscribe G2. Generalised Procrustes superimposition was performed on the coordinates and allometry corrected for using pooled regression analysis. Principal Component Analysis (PCA) was conducted and interpreted with respect to diet. PCA differentiates between genera in Ursidae and known dietary composition in extant Ursus on principal components 1 and 2. The position of U. spelaeus in morphospace suggests more foliage intake, relative to the extant brown bear Ursus arctos . These results suggest that the diet of U. spelaeus likely consisted mostly of foliage. Two cave bear specimens from Moravský Kras and Merkensteinhöhle are separate from the others on PC2; this may be due to dietary differentiation, but the exact interpretation remains elusive, because precise geographical and temporal data are missing for the specimen from Moravský Kras. [ABSTRACT FROM AUTHOR]

The migration of Ursus ingressus from Southern to Western Europe, where it replaced native forms of Ursus spelaeus , is well documented. However, its occurrence in Central and Eastern European countries is unexplored. We have characterized the cave bear population inhabiting the Sudetes Mountains during the Late Pleistocene. DNA analyses were performed on 39 cave bear specimens from the Niedzwiedzia Cave. Ten successfully yielded the 254-bp sequences of an mtDNA control region. Phylogenetic analyses allowed assignment of nine samples to the U. ingressus haplogroup and one to brown bear ( Ursus arctos ). The mtDNA haplotypes of U. ingressus formed a single cluster and differed from haplotypes obtained for cave bears from other excavation sites in Europe. Uranium-thorium and radiocarbon dating of selected samples has shown that U. ingressus appeared in the Sudetes region at least 80,000 years ago. This finding may suggest that the appearance of U. ingressus in this area resulted from migration that occurred earlier than the colonization of the Alps and Swabian Jura. It is possible that migration of U. ingressus proceeded along the Carpathian and Sudetes arc. [ABSTRACT FROM AUTHOR]

New research of the Izabela Textorisová Cave in the Veľká Fatra Mts. and the Javorinka Cave in the Vysoké Tatry Mts. yielded important data on Western Carpathians cave bear palaeopopulations. The radiometric dating of cave bear fossils from the Javorinka Cave (c. 51,000 14 C BP) represents one of the oldest documented record of cave bears in Slovakia. The site is also the highest documented occurrence of cave bears with an altitude more than 1500 m. The radiocarbon dates from the Izabela Textorisová Cave (30,181–30,190 cal. BP) represent the last known occurrence of cave bears in the Slovakian Western Carpathians. [ABSTRACT FROM AUTHOR]

Dental cementum from lions (Panthera fossilis) and bears (Ursus deningeri) found in Za Hájovnou Cave in Javoříčko Karst were studied. In order to determine the reasons why bears and cave lions crawled into the cave, tooth cement increments were analysed. I used thin sections of the tooth roots of these mammals to determine the seasonality of the death. The tooth samples were taken from different parts of the cave complex: Chodba nadĕje, Kostnice II, Narozeninová chodba and Propástka 1. These data indicate that bears mostly sought out this cave as a place to hibernate. The exception was one specimen which died there between spring and summer, probably as the result of illness or injury. Five bears died in the early stages of hibernation and seven during winter. In the case of the cave lions (Panthera fossilis), these were predominantly young and thus inexperienced and were therefore probably attracted by the bear carcasses in the caves. It is highly likely that these carcasses attracted not only young and inexperienced lions, but also other predators (such as hyenas, or adult lions). Za Hájovnou Cave was probably used as a winter den by bears and especially by expectant mothers for the birth of their cubs. Other species present may be there due to predatory activity or were exploiting the carcasses of dead bears during the winter. [ABSTRACT FROM AUTHOR]

8,210 ursid dental and osteological elements, found in fossiliferous deposits of the Moravian Za Hájovnou Cave between 1987 and 2007, were analysed from basic palaeobiological and taphonomic viewpoints. Minimally 60% of the entire ursid record is represented by Middle Pleistocene bear assemblage(-s) (Ursus ex gr. deningeri, MIS 9 to probably MIS 11), consisting of at least 21 juveniles and 16 (prime) adults. Neonates and senile adults are represented only sporadically which could indicate an assemblage(-s) with non-violent attrition. From the viewpoint of sex ratio, females predominate over males (sex index = 63.64). The main cause of individual death was probably starvation during hibernation, although other reasons for perishing (disease, activity of predators, etc.) cannot be excluded. The remainder of the fossil record at the site, from late Middle Pleistocene to Late Pleistocene deposits, is probably represented by remains of cave bears (U. ex gr. spelaeus). [ABSTRACT FROM AUTHOR]

The proposed dietary pattern of extinct Late Pleistocene cave bears ( Ursus spelaeus Rosenmüller, 1794) has become controversial, as some authors have suggested that they were strictly vegetarian, whereas others maintain they were omnivores that at times ate large amounts of animal protein. We evaluated these alternatives by compiling stable isotope data of carbon (δ13C) and nitrogen (δ15N) from the bone collagen of adult European cave bears from the Late Pleistocene (Marine Isotopic Stage 3). The data include previously published analyses and additional data from the southeastern European (Carpathian) sites of Cioclovina, Muierii, Oase, and Urşilor. The cave bear isotopic values from bone collagen were compared with those from hair keratin occurring in grizzly bears ( Ursus arctos horribilis Ord, 1815) collected from 1989 to 2009 in the western United States (Yellowstone National Park). The Yellowstone bears have access to a wide diversity of plants and animals, such that their diets can range from vegetarian to carnivorous. Thus, there was considerable δ13C and δ15N variation among the grizzly bear isotopic values, and the cave bear isotopic variation was encompassed within the overall grizzly bear isotopic distribution. More importantly, the δ15N distributions, reflecting principally trophic level, were not different between the cave bears and the grizzly bears; the cave bear values are, on average, slightly higher or lower than those of the grizzly bears, depending on the criteria for inclusion in the comparisons. It is therefore no longer appropriate to view Late Pleistocene cave bears as strictly or even predominantly vegetarian but as flexible omnivores within their diverse communities. [ABSTRACT FROM AUTHOR]

Despite the greater information content of genomic DMA, ancientDNA studies have largely been limited to the amplification ofmitochondrial sequences. Here we describe metagenomic librariesconstructed with unamplified DNA extracted from skeletal remains of two40,000-year-old extinct cave bears. Analysis of ∼1 megabase ofsequence from each library showed that despite significant microbialcontamination, 5.8 and 1.1% of clones contained cave bear inserts,yielding 26,861 base pairs of cave bear genome sequence. Comparison ofcave bear and modern bear sequences revealed the evolutionaryrelationship of these lineages. The metagenomic approach used hereestablishes the feasibility of ancient DNA genome sequencing programs. [ABSTRACT FROM AUTHOR]

Abstract: The Cave Bear skull is characterized in classic descriptions by a strong development in the frontal area. This feature gives it a characteristic step profile in lateral view. Such morphology is usually present in some adult males (brachycraneous), but it has not been described for females or young individuals. In this work, we present a study on variation in the size and shape in Cave Bear skulls during ontogenetic development, as well as on variability due to sexual dimorphism in adult individuals. In order to study these features, a morphometric analysis (principal component analysis) was made, based on both classical measurements and a group of non-conventional metric data using landmarks established by the authors. The results allow us to differentiate between those parts of the skull that, in adult specimens, present a shape-based sexual dimorphism and those presenting differences only in size. The ontogenetic study can provide data on the age at which the differentiation between males and females starts, and in which regions of the skull these differences are most pronounced. [Copyright &y& Elsevier]

Determination of the sex-ratio of a fossil population is essential for understanding the palaeoethology of a taxon, and this is especially true for the cave bear (Ursus spelaeus). Classical methods for determining sex-ratios such as analyses using uni and bivariate plots are based on an arbitrary fixing of the limit between the sexes. Therefore, a more robust statistical method termed mixture analysis has been applied in this study to test all the postcranial remains of cave bear (essentially carpals, tarsals and metapodials) derived from the Upper Pleistocene site of Fate (Liguria, Italy).Results give a sex-ratio of about 35% female individuals and show a clear predominance of males. Mixture analysis appears to be a reliable method for sex-ratio determination in U. spelaeus. In this study, few dimensions have been excluded because of a significant error in sex classification. The numerous measurements identified as good predictors of sexual dimorphism in the cave bear are probably linked to the marked sexual differences in the body mass of the animal. Palaeobiological interpretations suggest that there are no available hypotheses to explain the high variability of sex-ratios documented for the cave bear in Palaeolithic sites. The individual animal behaviour appears to be the only criteria in determining their choice of a winter den. But trophic and social regulations on living populations may have influenced this choice.The association between mortality profiles and sex-ratios appears to be related to the general function of a den. The thanatocenosis of cave bears in the Fate assemblage indicates the presence of a high number of juveniles and male individuals, such that the site may have served either as a nursery or and as a male den. [Copyright &y& Elsevier]