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New Carnivore remains associated with Gigantopithecus blacki are described from Yanliang Cave, Chongzuo, Guangxi Zhuang Autonomous Region, South China. New specimens of Megantereon have been identified as Megantereon microta sp. nov. based on the previously unknown characteristics, such as small overall size, p4 and m1 dental proportions, p3 with two separated roots and large P4 protocone. M . microta sp. nov. differs from Megantereon whitei from Africa mainly by the characters of p3 and lacking a p3–p4 diastema. Compared with other Megantereon species from China, M . microta sp. nov. is considered to be more primitive in dental characters, such as large P4 protocone, p3 with two separated roots, and short canine-p3 diastema. The Pachycrocuta licenti and Ursus thibetanus from Yanliang Cave are consistent with their appearance during the early Early Pleistocene in southern China. Combining the biostratigraphical and biochronological evidence, the Yanliang fauna can be best correlated with Baikong fauna in the same area, which is the early Early Pleistocene (∼2.0 Ma). [ABSTRACT FROM AUTHOR]

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]

Background: The study of postnatal ontogeny can provide insights into evolution by offering an understanding of how growth trajectories have evolved resulting in adult morphological disparity. The Ursus lineage is a good subject for studying cranial and mandibular shape and size variation in relation to postnatal ontogeny and phylogeny because it is at the same time not diverse but the species exhibit different feeding ecologies. Cranial and mandibular shapes of Ursus arctos (brown bear), U. maritimus (polar bear), U. americanus (American black bear), and the extinct U. spelaeus (cave bear) were examined, using a three-dimensional geometric morphometric approach. Additionally, ontogenetic series of crania and mandibles of U. arctos and U. spelaeus ranging from newborns to senile age were sampled. Results: The distribution of specimens in morphospace allowed to distinguish species and age classes and the ontogenetic trajectories U. arctos and U. spelaeus were found to be more similar than expected by chance. Cranial shape changes during ontogeny are largely size related whereas the evolution of cranial shape disparity in this clade appears to be more influenced by dietary adaptation than by size and phylogeny. The different feeding ecologies are reflected in different cranial and mandibular shapes among species. Conclusions: The cranial and mandibular shape disparity in the Ursus lineage appears to be more influenced by adaptation to diet than by size or phylogeny. In contrast, the cranial and mandibular shape changes during postnatal ontogeny in U. arctos and U. spelaeus are probably largely size related. The patterns of morphospace occupation of the cranium and the mandible in adults and through ontogeny are different. [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]

Abstract: The paleontological analysis of the fauna from three Late Pleistocene localities in Southern Caucasus (Sakažhia, Ortvala, and Bronze cave) confirmed the presence of Ursus spelaeus, Canis lupus, Equus ferus, Rhinocerotidae, Cervus elaphus, Capreolus capreolus, Alces alces, Bison priscus, Capra caucasica, Ovis ammon and Sus scrofa. The study also permitted the identification of new taxa for these localities. There may be the presence of reindeer (Rangifer tarandus) at Sakažhia, however it has not yet been confirmed. Moreover, remains of aurochs (Bos primigenius) were identified, in particular at Bronze cave where its abundance is exceptional. Indeed, Bos and Bison are generally very rare in Southern Caucasus. The analysis of the proportion of the different species in each locality revealed the two types of occupations of the caves, one dominated by hominids and the other by carnivores. At Sakažhia, where fauna is dominated by the presence of cave bear, the cave was seasonally occupied by Neanderthal groups. On the other hand, Bronze cave corresponds to a habitat of hunters, which occupied the site for longer periods. [Copyright &y& Elsevier]

The article presents a study on the remains of carnivore found at the paleontological site of Cal Guardiola in Catalonia, Spain. It provides description of the remains of the carnivore assemblage found in the area which include Ursus deningeri, Canis mosbachesis, Pachycrocuta brevirostris. Moreover, it notes that the carnivore remains shows the latest occurrences of the hyenid Pachycrocuta in Europe and manifest the coexistence of two distinct ursid lineages by the latest Early Pleistocene.

Background: New polymorphism datasets from heterochroneous data have arisen thanks to recent advances in experimental and microbial molecular evolution, and the sequencing of ancient DNA (aDNA). However, classical tools for population genetics analyses do not take into account heterochrony between subsets, despite potential bias on neutrality and population structure tests. Here, we characterize the extent of such possible biases using serial coalescent simulations. Methodology/Principal Findings: We first use a coalescent framework to generate datasets assuming no or different levels of heterochrony and contrast most classical population genetic statistics. We show that even weak levels of heterochrony (~10% of the average depth of a standard population tree) affect the distribution of polymorphism substantially, leading to overestimate the level of polymorphism h, to star like trees, with an excess of rare mutations and a deficit of linkage disequilibrium, which are the hallmark of e.g. population expansion (possibly after a drastic bottleneck). Substantial departures of the tests are detected in the opposite direction for more heterochroneous and equilibrated datasets, with balanced trees mimicking in particular population contraction, balancing selection, and population differentiation. We therefore introduce simple corrections to classical estimators of polymorphism and of the genetic distance between populations, in order to remove heterochrony-driven bias. Finally, we show that these effects do occur on real aDNA datasets, taking advantage of the currently available sequence data for Cave Bears (Ursus spelaeus), for which large mtDNA haplotypes have been reported over a substantial time period (22-130 thousand years ago (KYA)). Conclusions/Significance: Considering serial sampling changed the conclusion of several tests, indicating that neglecting heterochrony could provide significant support for false past history of populations and inappropriate conservation decisions. We therefore argue for systematically considering heterochroneous models when analyzing heterochroneous samples covering a large time scale. [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]