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The scale and nature of early cultivation are topics that have received relatively limited attention in research on the origins of agriculture. In Southwest Asia, one the earliest centers of origin worldwide, the transition to food production is commonly portrayed as a macroevolutionary process from hunter-gatherer through to cultivator-forager and farming stages. Climate change, resource intensification, sedentism, rising population densities, and increasing social complexity are widely considered by prehistorians as pivotal to the emergence of protoagricultural village life. In this paper we revisit these narratives that have been influenced by culture-history and social evolution, together forming the dominant theoretical paradigms in the prehistory of Southwest Asia. We propose a complementary contextual approach seeking to reconstruct the historical development of Early Holocene plant-food production and its manifold sociocultural environments by intersecting multiple lines of evidence on the biology of plant domestication, resource management strategies, settlement pattern.;, cultivation and harvesting technologies, food storage, processing and consumption, ritual practices and symbolic behaviors. Furthermore, we propose that early plant-food production in Southwest Asia should be dissociated from ethnographically derived notions of sedentary village life. Plants emerge as important components of community interactions and ritual performances involving suprahousehold groups that were mediated through communal focd consumption. [ABSTRACT FROM AUTHOR]

A mismatch between model- and proxy-based Holocene climate change, known as the "Holocene conundrum", may partially originate from the poor spatial coverage of climate reconstructions in, for example, Asia, limiting the number of grid cells for model–data comparisons. Here we investigate hemispheric, latitudinal, and regional mean time series and time-slice anomaly maps of pollen-based reconstructions of mean annual temperature, mean July temperature, and annual precipitation from 1908 records in the Northern Hemisphere extratropics. Temperature trends show strong latitudinal patterns and differ between (sub-)continents. While the circum-Atlantic regions in Europe and eastern North America show a pronounced Middle Holocene temperature maximum, western North America shows only weak changes, and Asia mostly shows a continuous Holocene temperature increase. Likewise, precipitation trends show certain regional peculiarities such as the pronounced Middle Holocene precipitation maximum between 40 and 50 ∘ N in Asia and Holocene increasing trends in Europe and western North America, which can all be linked with Holocene changes in the regional circulation pattern responding to temperature change. Given a background of strong regional heterogeneity, we conclude that the calculation of global or hemispheric means, which initiated the Holocene conundrum debate, should focus more on understanding the spatiotemporal patterns and their regional drivers. [ABSTRACT FROM AUTHOR]

The origin of the temperature divergence between Holocene proxy reconstructions and model simulations remains controversial, but it possibly results from potential biases in the seasonality of reconstructions or in the climate sensitivity of models. Here we present an extensive dataset of Holocene seasonal temperatures reconstructed using 1310 pollen records covering the Northern Hemisphere landmass. Our results indicate that both summer and winter temperatures warmed from the early to mid-Holocene (~11–7 ka BP) and then cooled thereafter, but with significant spatial variability. Strong early Holocene warming trend occurred mainly in Europe, eastern North America and northern Asia, which can be generally captured by model simulations and is likely associated with the retreat of continental ice sheets. The subsequent cooling trend is pervasively recorded except for northern Asia and southeastern North America, which may reflect the cross-seasonal impact of the decreasing summer insolation through climatic feedbacks, but the cooling in winter season is not well reproduced by climate models. Our results challenge the proposal that seasonal biases in proxies are the main origin of model–data discrepancies and highlight the critical impact of insolation and associated feedbacks on temperature changes, which warrant closer attention in future climate modelling. The study reconstructed Holocene seasonal temperatures using 1,310 pollen records covering the Northern Hemisphere landmass, and show that both summer and winter temperatures peaked at ~7 ka BP, but with significant spatial variability. [ABSTRACT FROM AUTHOR]

Westerlies‐dominated arid central Asia (ACA) has a very fragile ecological environment that highly depends on the available moisture sources. However, the moisture history of this region during the Holocene has been a controversial topic for several decades. Here, we performed optically stimulated luminescence (OSL) dating and grain‐size analysis of aeolian sediments from the eastern Balikun Basin. Our results demonstrated that the early Holocene climate in the Balikun Basin was dry (before ~6.5 ka) and then became wetter during the mid–late Holocene. This Holocene climate pattern correlates well with other climatic inferences from various proxies acquired at various ACA locations, further supporting an earlier view that the Holocene climate in ACA was out of phase with that of the East Asia summer monsoon. Furthermore, an extremely dry event at 4.3–2.6 ka correlated well with pollen records and a decrease of ~4°C in temperature in the western Balikun Lake, but this event was not evident in other ACA regions. Finally, Mingsha Shan Sand Dunes in the eastern Balikun Basin initially accumulated in the earliest Holocene. We suggest that the early Holocene dry climate in the ACA region and the local geomorphology are responsible for the formation of the Mingsha Shan Sand Dunes. [ABSTRACT FROM AUTHOR]

To advance our knowledge of the response of midlatitude westerlies to various external forcings, we investigate the meridional shift of midlatitude westerlies over arid central Asia (ACA) during the past 21 000 years, which experienced more varied forcings than the present day based on a set of transient simulations. Our results suggest that the evolution of midlatitude westerlies over ACA and driving factors vary with time and across seasons. In spring, the location of midlatitude westerlies overACAoscillates largely during the last deglaciation, driven by meltwater fluxes and continental ice sheets, and then shows a long-term equatorward shift during the Holocene controlled by orbital insolation. In summer, orbital insolation dominates the meridional shift of midlatitude westerlies, with poleward and equatorward migration during the last deglaciation and the Holocene, respectively. From a thermodynamic perspective, variations in zonal winds are linked with the meridional temperature gradient based on the thermal wind relationship. From a dynamic perspective, variations in midlatitude westerlies are mainly induced by anomalous sea surface temperatures over the Indian Ocean through the Matsuno–Gill response and over the North Atlantic Ocean by the propagation of Rossby waves, or both, but their relative importance varies across forcings. Additionally, the modeled meridional shift of midlatitude westerlies is broadly consistent with geological evidence, although model–data discrepancies still exist. Overall, our study provides a possible scenario for a meridional shift of midlatitude westerlies over ACA in response to various external forcings during the past 21 000 years and highlights important roles of both the Indian Ocean and the North Atlantic Ocean in regulating Asian westerlies, which may shed light on the behavior of westerlies in the future. [ABSTRACT FROM AUTHOR]

Background: Siberian musk deer, one of the seven species, is distributed in coniferous forests of Asia. Worldwide, the population size of Siberian musk deer is threatened by severe illegal poaching for commercially valuable musk and meat, habitat losses, and forest fire. At present, this species is categorized as Vulnerable on the IUCN Red List. However, the genetic information of Siberian musk deer is largely unexplored. Results: Here, we produced 3.10 Gb draft assembly of wild Siberian musk deer with a contig N50 of 29,145 bp and a scaffold N50 of 7,955,248 bp. We annotated 19,363 protein-coding genes and estimated 44.44% of the genome to be repetitive. Our phylogenetic analysis reveals that wild Siberian musk deer is closer to Bovidae than to Cervidae. Comparative analyses showed that the genetic features of Siberian musk deer adapted in cold and high-altitude environments. We sequenced two additional genomes of Siberian musk deer constructed demographic history indicated that changes in effective population size corresponded with recent glacial epochs. Finally, we identified several candidate genes that may play a role in the musk secretion based on transcriptome analysis. Conclusions: Here, we present a high-quality draft genome of wild Siberian musk deer, which will provide a valuable genetic resource for further investigations of this economically important musk deer. [ABSTRACT FROM AUTHOR]

The Ayeyawady delta is the last Asian megadelta whose evolution has remained essentially unexplored so far. Unlike most other deltas across the world, the Ayeyawady has not yet been affected by dam construction, providing a unique view on largely natural deltaic processes benefiting from abundant sediment loads affected by tectonics and monsoon hydroclimate. To alleviate the information gap and provide a baseline for future work, here we provide a first model for the Holocene development of this megadelta based on drill core sediments collected in 2016 and 2017, dated with radiocarbon and optically stimulated luminescence, together with a reevaluation of published maps, charts and scientific literature. Altogether, these data indicate that Ayeyawady is a mud-dominated delta with tidal and wave influences. The sediment-rich Ayeyawady River built meander belt alluvial ridges with avulsive characters. A more advanced coast in the western half of the delta (i.e., the Pathein lobe) was probably favored by the more western location of the early course of the river. Radiogenic isotopic fingerprinting of the sediment suggests that the Pathein lobe coast does not receive significant sediment from neighboring rivers. However, the eastern region of the delta (i.e., Yangon lobe) is offset inland and extends east into the mudflats of the Sittaung estuary. Wave-built beach ridge construction during the late Holocene, similar to several other deltas across the Indian monsoon domain, suggests a common climatic control on monsoonal delta morphodynamics through variability in discharge, changes in wave climate or both. Correlation of the delta morphological and stratigraphic architecture information on land with the shelf bathymetry, as well as its tectonic, sedimentary and hydrodynamic characteristics, provides insight on the peculiar growth style of the Ayeyawady delta. The offset between the western Pathein lobe and the eastern deltaic coast appears to be driven by tectonic-hydrodynamic feedbacks as the extensionally lowered shelf block of the Gulf of Mottama amplifies tidal currents relative to the western part of the shelf. This situation probably activates a perennial shear front between the two regions that acts as a leaky energy fence. Just as importantly, the strong currents in the Gulf of Mottama act as an offshore-directed tidal pump that helps build the deep mid-shelf Mottama clinoform with mixed sediments from the Ayeyawady, Sittaung and Thanlwin rivers. The highly energetic tidal, wind and wave regime of the northern Andaman Sea thus exports most sediment offshore despite the large load of the Ayeyawady River. [ABSTRACT FROM AUTHOR]