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The two living species of bison (European and American) are among the few terrestrial megafauna to have survived the late Pleistocene extinctions. Despite the extensive bovid fossil record in Eurasia, the evolutionary history of the European bison (or wisent, Bison bonasus) before the Holocene (<11.7 thousand years ago (kya)) remains a mystery. We use complete ancient mitochondrial genomes and genome-wide nuclear DNA surveys to reveal that the wisent is the product of hybridization between the extinct steppe bison (Bison priscus) and ancestors of modern cattle (aurochs, Bos primigenius) before 120 kya, and contains up to 10% aurochs genomic ancestry. Although undetected within the fossil record, ancestors of the wisent have alternated ecological dominance with steppe bison in association with major environmental shifts since at least 55 kya. Early cave artists recorded distinct morphological forms consistent with these replacement events, around the Last Glacial Maximum (LGM, ∼21-18 kya).

Leporids (Lagomorpha, Mammalia), especially the mountain hare (Lepus timidus) and the European rabbit (Oryctolagus cuniculus), have been among the most abundant small game in western Europe since the Pleistocene. These animals are preferred prey for more than 40 predators, which increases the chances of finding their skeletal remains at archaeological or natural sites, and in particular karstic formations alternately occupied by Palaeolithic human societies and other predators. Moreover, specific eco‐ethological characteristics for both species also offer the possibility to produce a substantial quantity of their bones accumulated by natural mortality without predation, making it more difficult to identify their origin in the fossil record. Despite this fact, the taphonomic signature of accidental‐natural accumulations of leporids in karsts, such as pitfalls, has never been properly characterised. In order to address these issues, we carried out a detailed taphonomic study of leporid remains in a pitfall without any evidence of human activity, namely at Coulet des Roches (Monieux, Vaucluse, south‐eastern France). At this site, leporids are the most abundant species throughout the Last Glacial Maximum sedimentary sequence. The bone accumulation was analysed in order to determine the most relevant criteria to identify a natural accumulation that results from the accidental fall of individuals in the pitfall. The relative proportions of each species are consistent with their current ethology, and their mortality profiles are compatible with the structure of a living natural population. The completeness rate of the different skeletal portions for both species is relatively high, bones are less fragmented and, unlike what might be expected, very few anatomical connections were preserved. The observed anatomical representation, breakage, and bone surface modification patterns are discussed and compared with available data concerning accumulations with predation. Taken together, the identified criteria contribute valuable help in the recognition of accidental mortality in the fossil record, as well as to evaluate the proportion of leporid bones accumulated naturally and those accumulated by predation, human or not, in a deposit. [ABSTRACT FROM AUTHOR]

The Asian black bear (Ursus thibetanus Cuvier, 1823) is a medium-sized ursid that currently mostly inhabits environments of dense foliage and forests in southern and eastern Asia. This species is currently extinct in Europe, but during the Middle Pleistocene and the beginning of the Late Pleistocene its distribution was wider and reached until Southern Siberia, the Ural Mountains, Caucasus and western Europe. The main objective of this work is to provide a detailed description of all the Ursus thibetanus remains from the Iberian Peninsula, describing for the first time the new remains, and discuss the chronological framework of the presence of this taxon in the largest of the southern European peninsulas. The Iberian Peninsula has yielded paleontological evidence of this taxon in five sites (Bolomor, Koskobilo, La Llanera, Cau d'en Borràs and Villavieja), and we present new paleontological evidence from the latter three sites, which is important due to the scarcity of U. thibetanus fossil remains. We compare the morphology of these new remains with both European Pleistocene fossils and recent U. thibetanus. Up until recently, its distribution in Iberia was thought to be restricted to the East of the Iberian Peninsula. But the recent identification of U. thibetanus remains in Koskobilo (Navarre) and in La Llanera (Oviedo) has resulted in a wider distribution of this species than what was previously thought. The dental remains from Koskobilo, La Llanera, Villavieja, Bolomor and Cau d'en Borràs fit well within the Pleistocene U. thibetanus from Europe morphologically and metrically. Some Iberian remains are morphologically similar to previously described U. thibetanus Pleistocene fossil subspecies. A M2 from Bolomor is morphologically closer to U. t. mediterraneus (MIS 7), and a M2 from Koskobilo is similar to U. t. kurteni (MIS 6–7). The postcranial fossil remains from Cau d'en Borràs and Villavieja fit well within the recent U. thibetanus range of variation. Except for the remains from Bolomor (MIS 5e and MIS 7), the rest of the Iberian U. thibetanus fossils are difficult to ascribe chronologically. Based on other biochronological proxies, Cau d'en Borràs and Koskobilo can tentatively be assigned to the MIS 7–5 range, Villavieja could be assigned to MIS 13–5, and La Llanera is probably the oldest record of U. thibetanus in Iberia (MIS 15–13). However, until new direct datings are performed on the sites, the proposed chronologies should be regarded with caution. • We identified new Pleistocene Ursus thibetanus fossils, which is interesting due to the of this species scarcity during Pleistocene. • The postcranial fossil sample is enlarged, while the majority of the fossil record correspond to cranio-dental remains. • A new site that extends the range of distribution for the U. thibetanus in the Iberian Peninsula is identified. • A detailed description of the dental morphology is performed, as well as a review of the literature. [ABSTRACT FROM AUTHOR]