Browsing by Author "Zazovskaya, EP"

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    Late Pleistocene chronology and environment of woolly rhinoceros (Coelodonta antiquitatis (Blumenbach, 1799)) in Beringia
    (Elsevier, 2021-07-01) Puzachenko, AY; Levchenko, VA; Bertuch, F; Zazovskaya, EP; Kirillova, IV
    Uncertain chronology and data scarcity have impeded realistic reconstructions of megafauna extinctions in the Late Pleistocene in several key regions of the Northern Hemisphere such as Beringia. This region was a refuge for several plants, animals during the extremely cold period of the Late Pleistocene in high Arctic latitudes. The woolly rhinoceros was one of the most widespread members of the megafauna in the Asiatic part of the region (West Beringia) between ∼60 and 14 cal ka BP. This study is based on statistical analyses of 20 newly obtained and 110 previously published radiocarbon dates. We found three large “waves” in the woolly rhinoceros range changes separated between themselves by the cold climatic Heinrich events (H2 and H4). The chronology of the woolly rhinoceros was overlaid on data of environmental changes obtained basing on 504 generalized early published pollen spectra throughout the species range and, separately, outside the range – in the east of the West Beringia realm and in East Beringia. In general, milder environmental conditions of MIS3 (57–29 ka BP) were more favourable for the woolly rhinoceros than the harsh conditions of the Last Glacial Maximum (∼29–15 cal ka BP) in MIS2. We have concluded that the feed base was unlikely the main limiting factor in the distribution of woolly rhinoceros in Western Beringia, and other ecological factors (temperature/precipitation) determined the species range and its oscillation over the MIS3–MIS2 stages. Based on summarizing available data and this research, we have proposed that there were sets of different reasons that prevented the woolly rhinoceros migration to the east of Beringia in different periods of the Late Pleistocene. Abrupt woolly rhinoceros extinction in Beringia between 15 and 14 cal ka BP coincided with the Bölling warming and the Older Dryas cooling. The ecological situation just before the extinction, associated with climate warming, moisture increasing and shrub tundra expansion in West Beringia, was qualitatively different from previous cases of the species range degradations in the second half of the Late Pleistocene. This multi-proxy study of woolly rhinoceros chronology provide a new basis for further understanding of its population history, demography, and biology in Beringia before its extinction. © 2021 Elsevier Ltd.
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    Palaeoecological and genetic analyses of Late Pleistocene bears in Asiatic Russia
    (Wiley, 2022-04-20) Kosintsev, PA; Bocherens, H; Kirillova, IV; Levchenko, VA; Zazovskaya, EP; Trofimova, SS; Lan, T; Lindqvist, C
    Brown bears are one of the few large carnivore species that survived the final Pleistocene wave of extinctions, perhaps in part owing to their wide ecological plasticity, variety of forms and polyphagia. Although the brown bear has become a well‐studied system, many questions remain regarding the ecological, trophic and genetic diversity throughout their distribution. For example, knowledge about Asiatic Russian brown bears from the Late Pleistocene arctic tundra steppe, an ecosystem with no analogue in modern times, is sparse. Here we compared diets, morphometry and genetic affinities of Late Pleistocene bears based on broadly sampled subfossil remains from Asiatic Russia. Collecting sites included the Ural Mountains, the lower reaches of the Irtysh River, the upper reaches of the Ob River, the Altai Mountains of western Siberia, the Indigirka–Kolyma Lowlands and northwestern Chukotka. An extremely large bear specimen from the middle Indigirka (41 090 14C a BP) that lived in landscapes of treeless shrubs and wet meadows had a diet composed principally of large herbivorous mammals. A bear from western Chukotka (25 880 14C a BP), much smaller in size, had a diet close to that of modern brown bears. These two Late Pleistocene NE Russian brown bears may comprise a previously undiscovered, but extinct, genetic lineage. At the end of the Pleistocene (MIS 3 and MIS 2), the brown bears from the Ob River Valley and Urals lived in periglacial forest‐steppes and those from the southern Urals in conditions of periglacial steppe. Brown bears from the Ob River valley and Urals, as well as ancient Altai bears, were characterized by a varied diet, from polyphagia to vegetarianism. In living brown bears, the proportions of different dietary foods are primarily related to food availability, which depends on the geographical zone and climatic conditions. We conclude that the same was true for Late Pleistocene brown bears of NE Siberia. © 2021 The Authors. Boreas published by John Wiley & Sons Ltd on behalf of The Boreas Collegium