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In the Cadomian orogenic belt a package of glacigenic sedimentary deposits have been recently described in the Armorican Massif (Normandy, France). The Granville Tillite Member, the middle part of the upper Granville Formation, is late Ediacaran in age. Maximum depositional ages of the pre- and syn-glacial sedimentary deposits obtained by LA-ICP-MS U–Pb detrital zircon dating indicate a maximum age of 561 ± 3 Ma. Combined with geochronological data on the previously described glacial deposits in Cadomia, West Africa, Arabia and Iran, the Granville Tillite Member appears to represent an Upper Ediacaran Glacial Period in northern peri-Gondwana, clearly younger than the c. 580 Ma old Gaskiers glaciation. Detailed mapping and analysis of the depositional regime of two sections near the city of Granville are indicative of two independent glaciomarine lower and upper tillite deposits separated by a distinct conglomeratic marker horizon, evidently a massive gravel beach horizon deposited during an interglacial stage. Age spectra of detrital zircon U–Pb ages constrain the palaeogeographical position of the upper Granville Formation to the periphery of the West African Craton. Post-Gaskiers aged glaciations in Cadomia and in West Africa should be grouped into an Upper Ediacaran Glacial Period dated at c. 565 Ma. This glacial period seems not to be related to the negative δ13C Shuram–Wonoka anomaly. Sedimentary deposits formed during the Upper Ediacaran Glacial Period show a scattered distribution along the marginal orogens of the Gondwana supercontinent independent of palaeolatitude and are coupled most likely to contemporaneous orogenic processes and uplift.

Aim: To identify hotspots of endemic and non-endemic avian diversity in the mountains of south-west China and delineate biodiversity corridors that connect the faunas of northern and southern Asia. To understand how biodiversity and endemism in this region has been maintained through palaeoclimate change. Location: The mountains of south-west China, spanning an elevational gradient > 7000 m. Methods: We used the distributional data of 752 breeding birds to investigate current patterns of diversity across elevational and geographical space. We simulated species richness under palaeoclimate models of global temperature change, assessing changes in species richness. Results: Contemporary species richness of non-endemic birds peaked at 800-1800 m elevation, while endemic richness peaked at 2000-3000 m. Richness of non-endemic birds was highest in the southern Hengduan Mountains and Yungui Plateau, while endemic richness peaked further north, extending into the mountains along the western edge of the Sichuan Basin. Under global warming models, species richness remained high throughout the Hengduan Mountains region. Under global cooling models, the Sichuan Basin showed increased richness. Conclusions: Endemism peaked in the mountains along the western edge of the Sichuan Basin, highlighting the importance of this region in promoting and maintaining diversity. This region has likely functioned as a biodiversity corridor, bridging the Palaearctic and Oriental biotas to the north and south. Climate simulations suggest that the mountains of south-west China can accommodate upslope range shifts in response to warming, but low elevation specialists may have experienced increased extinction probabilities during cold periods in the recent past, which may in part explain the current mid-elevation diversity peak. During glacial periods the Sichuan Basin likely served as a warm refugium for montane birds. Steep environmental heterogeneity has been a key to maintaining high diversity and endemism in the region during palaeoclimate change. These same features will likely shape the effects of future climate change on biodiversity in the region.

The rainfall changes in East Asian summer monsoon (EASM) regions on the orbital timescale remain controversial due to the lack of reliable rainfall records. Here, we present new multiproxy records ( δ 18 O, δ 13 C, Sr/Ca and Mg/Ca) of a 230 Th-dated stalagmite from Hulu Cave in central eastern China. Multiproxy records reconstruct a regional hydroclimate history from 340 to 261 kyr BP (thousand years before present), approximately covering the antepenultimate glacial period. The δ 18 O record is dominated by the precessional cycles, suggesting that EASM responds to changes in Northern Hemisphere summer insolation (NHSI) on the orbital timescale. Significant correlations amongst the δ 13 C, Sr/Ca and Mg/Ca suggest that a common factor, i.e., the local hydrological cycle, controlled their variability, and their leading principal component can be used as a proxy linked to regional rainfall. This composite record bears a good similarity to those from the Chinese Loess Plateau, showing a gradually decreasing rainfall during the antepenultimate glacial period, consistent with changes in global ice volume. Superimposed on the long-term trend, three relative wetter intervals were responding to the higher NHSI periods, suggesting that EASM rainfall variability was induced by integrated effects of global ice volume and NHSI. The increased ice sheets and lower NHSI resulted in an increased meridional temperature gradient and southward shift of the westerlies, which shortened the duration of Meiyu and midsummer rainfall. The differences between the rainfall record and the stalagmite δ 18 O record indicate that the latter represents the overall EASM intensity linked to monsoon circulation, but does not directly reflect the rainfall changes at the cave sites.

Geranium erianthum is an alpine plant growing in dry habitats, which is distributed from East Asia to northern coastal regions of the northern Pacific. The ice-free area around the current Bering Strait (i.e., Beringia) had played an important role in range expansion into neighboring regions such as East Asia and North America for some alpine plants. However, recent studies suggest that some alpine plants in snowbed environment spread from East Asia to northern coastal regions of the northern Pacific. In this study, we investigated phylogenetic relationships and genetic differentiations among populations of G. erianthum and the related species using the chloroplast genome and single-nucleotide polymorphisms, to evaluate the alternative biogeographic hypotheses in which region of Beringia, British Columbia or East Asia is probable for its distributional origin. Range reconstruction based on phylogenetic tree of chloroplast genome indicated G. erianthum and related species originated in East Asia, from where G. erianthum migrated eastward into Beringia and British Columbia. In addition, nuclear genome-wide SNPs indicated that no significant genetic differentiation was detected between Japanese and Beringian populations. The lack of genetic differentiation suggests that the current range of G. erianthum resulted from rapid range expansion during the latter period of the last glacial era. Overall, the East Asian refugium hypothesis was applicable to the alpine plant G. erianthum in dry habitat, indicating that range expansion pattern from East Asia into the northern Pacific may be more common rather than limited for snowbed species.

Aim: We compared the power of different nuclear markers to investigate genetic structure of southern Balkan wild boar. We distinguished between historic events, such as isolation in different refugia during glacial periods, from recent demographic processes, such as naturally occurring expansions. Location: Southern Balkans/Greece. Methods: We sampled 555 wild boars from 20 different locations in southern Balkans/Greece. All individuals were analysed with 10 microsatellites and a subgroup of 91 with 49,508 single nucleotide polymorphisms (SNPs). Patterns of genetic structure and demographic processes were assessed with Bayesian clustering, linkage disequilibrium and past effective population size estimation analysis. Results: Both microsatellite and SNP data analyses detected genetic structure caused by historic events and support the existence of three groups in the studied area. A hybrid zone between two of the groups was also detected. We also showed that genome-wide SNP data analysis can identify recent events in bottlenecked populations. Main conclusions: We inferred the three groups diverged ~50,000-10,000 YR BP when populations contracted to different refugia. Our findings strengthened the evidence that the southern Balkan area was a glacial refugium including further local smaller refugia. Genome-wide genotyping inferred a recent population expansion that can mimic a 'refugium within refugium' scenario. It seems that microsatellite data tend to overestimate genetic structure when genetic drift happens in bottlenecked populations over a short distance. Therefore, genome-wide SNPs are more powerful at inferring phylogeography in natural populations, resolving inconsistencies from mitochondrial and microsatellite data sets.

While studies of modern plants indicate negative responses to low [CO2] that occurred during the last glacial period, studies with glacial plant material that incorporate evolutionary responses are rare. In this study, physiological responses to changing [CO2] were compared between glacial (La Brea tar pits) and modern Juniperus trees from southern California. Carbon isotopes were measured on annual rings of glacial and modern Juniperus. The intercellular: atmospheric [CO2] ratio (c i/c a) and intercellular [CO2] (c i) were then calculated on an annual basis and compared through geologic time. Juniperus showed constant mean c i/c a between the last glacial period and modern times, spanning 50 000 yr. Interannual variation in physiology was greatly dampened during the last glacial period relative to the present, indicating constraints of low [CO2] that reduced responses to other climatic factors. Furthermore, glacial Juniperus exhibited low c i that rarely occurs in modern trees, further suggesting limiting [CO2] in glacial plants. This study provides some of the first direct evidence that glacial plants remained near their lower carbon limit until the beginning of the glacial–interglacial transition. Our results also suggest that environmental factors that dominate carbon-uptake physiology vary across geologic time, resulting in major alterations in physiological response patterns through time.

Discussing the development and shrinkage process of glaciers is of great significance for the in–depth comprehension of regional environmental evolution and predicting global changes. However, there is little understanding of the developmental and retreat processes of mountain glaciers during the Late Quaternary (150 ka) in the East Asian Monsoon region. Using the latest chronological glacial data from eastern China, Taiwan, the Russian Far East, and the Japanese islands of Hokkaido and Honshu, which are all regions impacted by the East Asian Monsoon, we screened reliable glacial age data. This study compiled and compared the age sequences of the different mountain glaciations (dating techniques included optically–stimulated luminescence (OSL), thermoluminescence (TL), electron spin resonance (ESR), U–series (U), cosmogenic nuclides (10Be/CRN), carbon–14 (14C) and potassium–argon (K–Ar), etc.). Based on the evolutionary features of the glaciations in these mountains, by comparison with the marine isotope stage (MIS) environment, the influence of monsoonal circulation patterns on the regional development of glaciers was analyzed. This study determined that Japanese mountain glacial stages since 150 ka are the most complete in the East Asian Monsoon region, having developed during MIS 6–1. Taiwanese mountain glaciers developed during MIS 4–1, but glacial stages in continental East Asia were relatively short, with glaciers first developing only during MIS 3b–1. The reason for this this phenomenon is that the tectonic uplift in different subregions was significantly different; on the other hand, it is also related to the difference of precipitation between land and sea in monsoon climate. By comparing the glacial glaciations in the East Asian Monsoon region with western China, we found that there were significant differences between the extent, onset time, and length of glacial periods. Since the Last Glacial Period, precipitation levels have become transitional and concentrated during the summer months, and temperatures have been continuously changing as a result of the many periodic changes in the East Asian Monsoon. From the Early Last Glacial Period (MIS 4) to the Middle Last Glacial Period (MIS 3b) to the Last Glacial Period (MIS 2/LGM–YD), climatic conditions increasingly restricted the development of glaciers; the regional environment continued to warm until glaciers completely disappeared during the Late Holocene.

Clues of climate change on the Alashan Plateau since the last glacial period (40 ka) are important for revealing the mechanism of desertification of middle-latitude deserts in the Northern Hemisphere (NH). Studies are still rare for the understanding of the specific relationship of climate changes between the Alashan Plateau and the global. Based on a systematic and comparative analysis of the existing research in China and the international academic community, this paper reviews the environmental evolution history of the Alashan Plateau since the last glacial period from the records of paleo-environment and geomorphological characteristics in different deserts of the plateau (e.g., Badanjilin, Tenggeli, and Wulanbuhe). From about 40 ka to the end of the last glacial maximum, the climate on the plateau was wetter than it is today, and to the end of the Pleistocene, the climate was generally dry and the aeolian activities were enhanced. However, the climate was arid during the whole last glacial period in the Wulanbuhe Desert, evidently different from the overall pattern of the plateau. The Tenggeli Desert was characterized by an arid climate in the early Holocene. The most controversial events for the Alashan Plateau are the drought events in the middle Holocene in the Badanjilin Desert. The role and impact of the westerlies and the East Asian Summer Monsoon (EASM) systems on the climate change of the desert and even the whole plateau is a vexed question that brings different views in different periods. There is still a lack of definite evidence representing the events of global environmental change that occurred on the plateau during the discussed period. The distinctive morphology of dune mountains and the distribution of sand dunes are mutually indicative of the direction and energy of wind systems on the plateau. It is suggested that appropriate wind energy is the significant key to the desertification in these middle-latitude deserts on the plateau. From a global-scale review of climate change, the desertification of the modern-scale sandy desert landscapes on the Alashan Plateau is generally related to the global glacial period and the cold and dry climate during the past 40 ka.

Glacial lakes are rapidly growing in response to climate change and glacier retreat. The role of these lakes as terrestrial storage for glacial meltwater is currently unknown and not accounted for in global sea level assessments. Here, we map glacier lakes around the world using 254,795 satellite images and use scaling relations to estimate that global glacier lake volume increased by around 48%, to 156.5 km3, between 1990 and 2018. This methodology provides a near-global database and analysis of glacial lake extent, volume and change. Over the study period, lake numbers and total area increased by 53 and 51%, respectively. Median lake size has increased 3%; however, the 95th percentile has increased by around 9%. Currently, glacial lakes hold about 0.43 mm of sea level equivalent. As glaciers continue to retreat and feed glacial lakes, the implications for glacial lake outburst floods and water resources are of considerable societal and ecological importance.Warming is increasing glacial lakes, and scaling relations show a 48% increase in volume for 1990 to 2018. All measures—area, volume, number—increased, providing water storage but also representing a potential hazard with the risk of outburst floods.