Post-glacial Colonization of Western Europe Brown Bears From a Cryptic Atlantic Refugium Out of the Iberian Peninsula

This is an Accepted Manuscript version, accepted for publication in Historical Biology.[Abstract] The European brown bear (Ursus arctos) shows a particular phylogeography that has been used to illustrate the model for contraction-expansion dynamics related to glacial refugia in Southern European peninsulas. Recent studies, however, have nuanced the once generally accepted paradigm, indicating the existence of cryptic refugia for some species further north. In this paper we collected available data on chronology and mitochondrial haplotypes from Western European brown bears, adding new sequences from present day individuals from the Cantabrian (North Iberia) area, in order to reconstruct the dynamics of the species in the region. Both genetics and chronology show that the Iberian Pleistocene lineages were not the direct ancestors of the Holocene ones, the latter entering the Peninsula belatedly (around 10,000 years BP) with respect to other areas such as the British Isles. We therefore propose the existence of a cryptic refugium in continental Atlantic Europe, from where the bears would expand as the ice receded. The delay in the recolonization of the Iberian Peninsula could be due to the orographic characteristics of the Pyrenean-Cantabrian region and to the abundant presence of humans in the natural entrance to the Peninsula.This work is part of the BIOGEOS [grant number CGL2014-57209-P] Research Project of the Spanish Ministry of Economy (MINECO/FEDER) and Competitiveness and a Consolidating grant from the Xunta de Galicia for emerging research groups [grant number GPC2015/024]Xunta de Galicia; GPC2015/02

Characterising the Cave Bear Ursus Spelaeus Rosenmüller by Zooms: A Review of Peptide Mass Fingerprinting Markers

[Abstract] In the last decade, the identification of bone fragments by peptide mass fingerprinting or zooarchaeology by mass spectrometry is developing as a powerful tool in Quaternary palaeontology. The sequence of amino acids that make up the bone collagen molecule shows slight variations between taxa, which can be studied by mass spectrometry for taxonomic purposes. This requires reference databases that allow peptide identification. Although the cave bear (Ursus spelaeus Rosenmüller, 1794) is a common component in many European Pleistocene cave sites, no peptide fingerprint taxonomic study has paid special attention to this species up to now. For peptide markers in Ursidae, the most recent proposal is based on collagen obtained from a modern brown bear sample. In this work we attempt to cover this gap by studying bone collagen of cave and brown bear samples from different origins and different chronology, applying matrix-assisted laser desorption/ionisation time-of-flight mass spectrometry (MALDI TOF). We also performed an in-silico study of ursid bone collagen sequences published in databases. In our results we detected some discrepancies between the peptides obtained from both in silico and MALDI TOF analysis of fossil collagen and those published in the literature, in which we conclude that there are some misidentified peptides. The identification of skeletal remains by means of their peptide fingerprint is proving to be a powerful tool in palaeontology, which will bear greater fruit once the limitations of a technique that is in its initial stages have been overcome.This study was carried out with the financial support of the project ED431B 2021/17 of the Autonomous Government of Galicia (Spain) awarded to AGDGalicia. Xunta; ED431B 2021/1

Neanderthal Use of Animal Bones as Retouchers at the Level XV of the Sopeña Rock Shelter (Asturias, Northern Spain)

[Abstract] Bone retouchers are a technological appliance used to perfect lithic tools efficiently. They are most frequently found in Middle Palaeolithic contexts. In this paper, we present a group of bone retouchers from the Mousterian Level XV of the Sopeña rock shelter (Asturias, Spain). The bone part preferred was the middle part of the shaft of long bones: Most of them are on metacarpals, followed by metatarsals, femurs, and tibias. The most used animal species is adult red deer. These retouchers have either one, two, or three active areas, with a central disposition. The impact marks are close together; oval pits are common, as well as straight, sinuous, and irregular grooves. The surfaces on these marks appear pitted and scaled. There are indications that the bones employed were relatively fresh. The length, width, and thickness of those bone fragments seem to be the determining factor when choosing them to be used as retouchers in the process of finishing lithic tools. The formats documented in Sopeña Level XV are similar to those found in other Mousterian sites in Iberia, although there is a certain variability regarding their width. The Neanderthals of Sopeña acquired the raw material for these retouchers from the faunal remains generated in the process of butchering and eating the animals. These retouchers were used as implements to perfect lithic tools made mainly on quartzite, and they were used repeatedly and maybe for a long time.AJR has a Postdoctoral Contract for Access to the Spanish System of Science, Technology and Innovation (Margarita Salas Grants) (MARSA 21/16) at the University of the Basque Country (UPV/EHU). The present article is part of the project “PALEOCROSS: Territorio y movilidad durante el Paleolítico superior en la Encrucijada vasca” (PID2021-126937NB-I00) (Spanish Ministry of Science). AJR is part of the Prehistory research group at the University of the Basque Country (UPV/EHU) (IT-622-13). Excavations at Sopeña were made possible by several grants to ACPLL by the following and all are gratefully acknowledged: Spanish Ramón y Cajal Program, National Geographic Society (CRE), Wenner-Gren Foundation, Institute of Human Origins (ASU), and Wings World Quest Foundatio

Ancient DNA reveals differences in behaviour and sociality between brown bears and extinct cave bears

Ancient DNA studies have revolutionized the study of extinct species and populations, providing insights on phylogeny, phylogeography, admixture and demographic history. However, inferences on behaviour and sociality have been far less frequent. Here, we investigate the complete mitochondrial genomes of extinct Late Pleistocene cave bears and middle Holocene brown bears that each inhabited multiple geographically proximate caves in northern Spain. In cave bears, we find that, although most caves were occupied simultaneously, each cave almost exclusively contains a unique lineage of closely related haplotypes. This remarkable pattern suggests extreme fidelity to their birth site in cave bears, best described as homing behaviour, and that cave bears formed stable maternal social groups at least for hibernation. In contrast, brown bears do not show any strong association of mitochondrial lineage and cave, suggesting that these two closely related species differed in aspects of their behaviour and sociality. This difference is likely to have contributed to cave bear extinction, which occurred at a time in which competition for caves between bears and humans was likely intense and the ability to rapidly colonize new hibernation sites would have been crucial for the survival of a species so dependent on caves for hibernation as cave bears. Our study demonstrates the potential of ancient DNA to uncover patterns of behaviour and sociality in ancient species and populations, even those that went extinct many tens of thousands of years ago

Isotopic signature in isolated south-western populations of European brown bear (Ursus arctos)

Stable isotope analysis of animal tissue samples is increasingly used to study the trophic ecology of target species. The isotopic signatures respond to the type of diet, but also to the environmental conditions of their habitat. In the case of omnivorous, seasonal or opportunistic feeding species, the interpretation of isotopic values is more complex, as it is largely determined by food selection, either due to individual choice or because of availability. We analysed C and N isotopes in brown bear (Ursus arctos) hair from four isolated populations of south-western Europe (Cantabrian, Pyrenees, Central Apennines and Alpine) accounting for the geographical and climatic differences among the four areas. We found inter-population differences in isotopic signatures that cannot be attributed to climatic differences alone, indicating that at least some bears from relatively higher altitude populations experiencing higher precipitation (Pyrenees) show a greater consumption of animal foods than those from lower altitudes (Cantabrian and Apennines). The quantification of isotopic niche space using Layman’s metrics identified significant similarities between the Cantabrian and Central Apennine samples that markedly differ from the Pyrenean and Alpine. Our study provides a baseline to allow further comparisons in isotopic niche spaces in a broad ranged omnivorous mammal, whose European distribution requires further conservation attention especially for southern isolated populations

Macrowear and occlusal microwear on teeth of cave bears Ursus spelaeus and brown bears Ursus arctos: Inferences concerning diet

Cave bears Ursus spelaeus are known from many limestone caves throughout the European Pleistocene. Despite the enormous quantities of fossils unearthed, many aspects of the cave bear ecology are still little known. Cave bear remains appear almost always with an array of variously sized tooth punctures, and the evidence from tooth mark types and sizes at several cave bear sites studied here indicates that cave bears themselves were responsible for the scavenging modifications recorded at these cave bear-only sites. Anatomical evidence for cave bear diet indicates that they had a tough-plant based diet and in addition, their powerful front legs suggest an enhanced digging capability that has sometimes been thought to relate to digging for tubers. Dental microwear analysis (DMA) approaches fossil and extant diets by comparing tooth wear for animals of known diet with that shown by fossils. Scanning electron microscope micrographs were prepared and the microwear features were measured. The results show differences in wear patterns between brown bears and cave bears from several locations and chronologies across northern Spain. There is no indication that these cave bears ate tubers or any food contaminated by soil; but the dental microwear observed indicates that they had a greater degree of bone consumption compared with brown bears.Peer reviewe