Palaeoenvironmental and chronological context of hominin occupations of the Armenian Highlands during MIS 3:Evidence from Ararat-1 cave

Archaeological and palaeoenvironmental evidence from the Armenian Highlands and wider southern Caucasus region emphasises the significance of Marine Oxygen Isotope Stage 3 (c. 57–29 ka) as a crucial period for understanding hominin behaviours amidst environmental fluctuations. Ararat-1 cave, situated in the Ararat Depression, Republic of Armenia, presents potential for resolving emerging key debates regarding hominin land use adaptations during this interval, due to its well-preserved lithic artefacts and faunal assemblages. We present the first results of combined sedimentological, geochronological (luminescence and radiocarbon), archaeological and palaeoecological (macrofauna, microfauna and microcharcoal) study of the Ararat-1 sequence. We demonstrate sediment accumulation occurred between 52 and 35 ka and was caused by a combination of aeolian activity, cave rockfall and water action. Whilst the upper strata of the Ararat-1 sequence experienced postdepositional disturbance due to faunal and anthropogenic processes, the lower strata remain relatively undisturbed. We suggest that during a stable period within MIS 3, Ararat-1 was inhabited by Middle Palaeolithic hominins amidst a mosaic of semi-arid shrub, grassland, and temperate woodland ecosystems. These hominins utilised local and distant toolstone raw materials, indicating their ability to adapt to diverse ecological and elevation gradients. Through comparison of Ararat-1 with other sequences in the region, we highlight the spatia

Pleistocene environments, climate, and human activity in Britain during Marine Isotope Stage 7: insights from Oak Tree Fields, Cerney Wick, Gloucestershire

Investigations at Oak Tree Fields, Cerney Wick, Gloucestershire, in western England have revealed a sequence of fluvial deposits dating from Marine Oxygen Isotope Stage (MIS) 7 to 5. At the base of the sequence, a series of gravel and sand facies were deposited, initially as part of a meandering river. Reductions in flow energy of the latter and avulsion led to the development of short-lived channels and episodic backwater environments, the deposits of which are recorded as Facies Associations 1–3. Poorly sorted, probably colluvial deposits formed beyond the limit of the channel (Facies Association 4). Mollusca, Coleoptera, plant macrofossils, pollen and vertebrates recovered from the channel facies indicate broadly similar climatic conditions throughout accretion. Temperature ranges derived from mutual climatic range analysis of the Coleoptera almost completely overlap with those of Cerney Wick at the present day, albeit that winters may have been cooler when the channel was active. Further, the floral and faunal data suggest that the meandering river flowed through an open grassland environment, the latter heavily grazed by large vertebrates, most notably mammoth. Most of the botanical and faunal remains, together with four optically stimulated luminescence (OSL) age estimates ranging from 225 ± 23 to 187 ± 19 ka, suggest correlation of the channel deposits with MIS 7. The basal deposits (Facies Association 1) yielded the majority of vertebrate remains and all the lithic artefacts, most of which seem likely to have travelled only a short distance. Although only a few artefacts were recovered, they add to the relatively limited evidence of human activity from the upper Thames. The channel deposits are overlain by sheet gravels (Facies Association 5) which are attributed to the Northmoor Member of the Upper Thames Formation. These were likely to have been deposited as bedload in a braided stream environment, while two OSL age estimates of 129 ± 14 and 112 ± 11 ka suggest accumulation during MIS 5

Short-term occupations at high elevation during the Middle Paleolithic at Kalavan 2 (Republic of Armenia)

The Armenian highlands encompasses rugged and environmentally diverse landscapes and is characterized by a mosaic of distinct ecological niches and large temperature gradients. Strong seasonal fluctuations in resource availability along topographic gradients likely prompted Pleistocene hominin groups to adapt by adjusting their mobility strategies. However, the role that elevated landscapes played in hunter-gatherer settlement systems during the Late Pleistocene (Middle Palaeolithic [MP]) remains poorly understood. At 1640 m above sea level, the MP site of Kalavan 2 (Armenia) is ideally positioned for testing hypotheses involving elevation-dependent seasonal mobility and subsistence strategies. Renewed excavations at Kalavan 2 exposed three main occupation horizons and ten additional low densities lithic and faunal assemblages. The results provide a new chronological, stratigraphical, and paleoenvironmental framework for hominin behaviors between ca. 60 to 45 ka. The evidence presented suggests that the stratified occupations at Kalavan 2 locale were repeated ephemerally most likely related to hunting in a high-elevation within the mountainous steppe landscape.info:eu-repo/semantics/publishedVersio

Population dynamics and demographic history of Eurasian collared lemmings.

BACKGROUND: Ancient DNA studies suggest that Late Pleistocene climatic changes had a significant effect on population dynamics in Arctic species. The Eurasian collared lemming (Dicrostonyx torquatus) is a keystone species in the Arctic ecosystem. Earlier studies have indicated that past climatic fluctuations were important drivers of past population dynamics in this species. RESULTS: Here, we analysed 59 ancient and 54 modern mitogenomes from across Eurasia, along with one modern nuclear genome. Our results suggest population growth and genetic diversification during the early Late Pleistocene, implying that collared lemmings may have experienced a genetic bottleneck during the warm Eemian interglacial. Furthermore, we find multiple temporally structured mitogenome clades during the Late Pleistocene, consistent with earlier results suggesting a dynamic late glacial population history. Finally, we identify a population in northeastern Siberia that maintained genetic diversity and a constant population size at the end of the Pleistocene, suggesting suitable conditions for collared lemmings in this region during the increasing temperatures associated with the onset of the Holocene. CONCLUSIONS: This study highlights an influence of past warming, in particular the Eemian interglacial, on the evolutionary history of the collared lemming, along with spatiotemporal population structuring throughout the Late Pleistocene

Palaeoenvironmental and chronological context of hominin occupations of the Armenian Highlands during MIS 3: Evidence from Ararat-1 cave

Archaeological and palaeoenvironmental evidence from the Armenian Highlands and wider southern Caucasus region emphasises the significance of Marine Oxygen Isotope Stage 3 (c. 57–29 ka) as a crucial period for understanding hominin behaviours amidst environmental fluctuations. Ararat-1 cave, situated in the Ararat Depression, Republic of Armenia, presents potential for resolving emerging key debates regarding hominin land use adaptations during this interval, due to its well-preserved lithic artefacts and faunal assemblages. We present the first results of combined sedimentological, geochronological (luminescence and radiocarbon), archaeological and palaeoecological (macrofauna, microfauna and microcharcoal) study of the Ararat-1 sequence. We demonstrate sediment accumulation occurred between 52 and 35 ka and was caused by a combination of aeolian activity, cave rockfall and water action. Whilst the upper strata of the Ararat-1 sequence experienced post-depositional disturbance due to faunal and anthropogenic processes, the lower strata remain relatively undisturbed. We suggest that during a stable period within MIS 3, Ararat-1 was inhabited by Middle Palaeolithic hominins amidst a mosaic of semi-arid shrub, grassland, and temperate woodland ecosystems. These hominins utilised local and distant toolstone raw materials, indicating their ability to adapt to diverse ecological and elevation gradients. Through comparison of Ararat-1 with other sequences in the region, we highlight the spatial variability of MIS 3 environments and its on hominin land use adaptations. This demonstrates the importance of the Armenian Highlands for understanding regional MP settlement dynamics during a critical period of hominin dispersals and evolution

Palaeoenvironmental and chronological context of hominin occupations of the Armenian Highlands during MIS 3:Evidence from Ararat-1 cave

Archaeological and palaeoenvironmental evidence from the Armenian Highlands and wider southern Caucasus region emphasises the significance of Marine Oxygen Isotope Stage 3 (c. 57–29 ka) as a crucial period for understanding hominin behaviours amidst environmental fluctuations. Ararat-1 cave, situated in the Ararat Depression, Republic of Armenia, presents potential for resolving emerging key debates regarding hominin land use adaptations during this interval, due to its well-preserved lithic artefacts and faunal assemblages. We present the first results of combined sedimentological, geochronological (luminescence and radiocarbon), archaeological and palaeoecological (macrofauna, microfauna and microcharcoal) study of the Ararat-1 sequence. We demonstrate sediment accumulation occurred between 52 and 35 ka and was caused by a combination of aeolian activity, cave rockfall and water action. Whilst the upper strata of the Ararat-1 sequence experienced post-depositional disturbance due to faunal and anthropogenic processes, the lower strata remain relatively undisturbed. We suggest that during a stable period within MIS 3, Ararat-1 was inhabited by Middle Palaeolithic hominins amidst a mosaic of semi-arid shrub, grassland, and temperate woodland ecosystems. These hominins utilised local and distant toolstone raw materials, indicating their ability to adapt to diverse ecological and elevation gradients. Through comparison of Ararat-1 with other sequences in the region, we highlight the spatial variability of MIS 3 environments and its on hominin land use adaptations. This demonstrates the importance of the Armenian Highlands for understanding regional MP settlement dynamics during a critical period of hominin dispersals and evolution

Ancient DNA of narrow-headed vole reveal common features of the Late Pleistocene population dynamics in cold-adapted small mammals.

International audienceThe narrow-headed vole, collared lemming and common vole were the most abundant small mammal species across the Eurasian Late Pleistocene steppe-tundra environment. Previous ancient DNA studies of the collared lemming and common vole have revealed dynamic population histories shaped by climatic fluctuations. To investigate the extent to which species with similar adaptations share common evolutionary histories, we generated a dataset comprised the mitochondrial genomes of 139 ancient and 6 modern narrow-headed voles from several sites across Europe and northwestern Asia covering approximately the last 100 thousand years (kyr). We inferred Bayesian time-aware phylogenies using 11 radiocarbon-dated samples to calibrate the molecular clock. Divergence of the main mtDNA lineages across the three species occurred during marine isotope stages (MIS) 7 and MIS 5, suggesting a common response of species adapted to open habitat during interglacials. We identified several time-structured mtDNA lineages in European narrow-headed vole, suggesting lineage turnover. The timing of some of these turnovers was synchronous across the three species, allowing us to identify the main drivers of the Late Pleistocene dynamics of steppe- and cold-adapted species