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Fiber technology, crucial to human societies for millennia, encompasses cordage and textiles. The development of fiber crops and the production of fiber-based clothing are significant components of the Neolithic Revolution. Despite China being an independent center for agriculture, the role of fiber technology in this context remains largely unexplored. In this project, we employed a comprehensive approach that combines microfossil analysis and use-wear examinations to study tools from the Peiligang site in North China. This site uniquely spans the Upper Paleolithic and early Neolithic periods, offering an ideal setting for investigating the evolution of fiber production. Our results reveal that some Paleolithic blades and scrapers were associated with fiber production, which coincided with ostrich eggshell beads and hematite during the cold and dry Last Glacial Maximum period. Responding to climatic fluctuations, fiber production played a significant role in subsistence and ritual activities. In the early Neolithic, advanced fiber production is evident. Two adjacent burials yield tools and microfossil remains representing a toolkit for fiber and possible textile production, including harvesting, retting, pounding, scraping, and sewing. Fibers recovered from human bones provide potential evidence of textile production and use. Dyeing with blue, black, and red colorants was common for textiles, cordages, and strings. These grave goods suggest the involvement of the deceased in craft production with bast fibers, possibly embodying the earliest specialization in fiber craft 8000 years ago in Neolithic China. [ABSTRACT FROM AUTHOR]

Antarctica has been proposed as a significant source of the meltwater that entered the oceans during meltwater pulse 1B (MWP1B) approximately 11 500 yr ago. Support for this scenario has been provided by evidence that the deep fjords of coastal Antarctica, which were heavily glaciated at the maximum of glaciation, were deglaciated at this time. Further support for this scenario was provided by the observation that the inter-hemispheric sea-level teleconnection associated with significant Southern Hemisphere deglaciation at this time provided an explanation of the highly non-monotonic relative sea-level histories recorded at sites on the coast of Scotland, a region which had also been heavily glaciated at the last glacial maximum. Furthermore, it has been argued that a significant contribution to MWP1B must have also been delivered to the oceans by the abrupt Northern Hemisphere warming that occurred at the end of the Younger Dryas (YD) cold reversal, which also occurred approximately 11 500 yr ago. Our focus in this paper is to distinguish between these two possible primary sources of MWP1B. The investigation of how local alterations to ice thicknesses are able to explain evidence which has previously been used to argue for an Antarctic dominant MWP1B will lead us to the conclusion that the Laurentide may be primary source of MWP1B. [ABSTRACT FROM AUTHOR]

Organic carbon (OC) burial in the Antarctic marginal seas is essential for regulating global climate, particularly due to its association with ice shelf retreat. Here, we analyzed total OC (TOC), total nitrogen (TN), radiocarbon isotope, n-alkanes and relative indicators in surface and core sediments from the Ross Sea, West Antarctica. Our aim was to investigate spatial and historical changes in OC sources, and to explore the influencing factors and implications for ice shelf retreat since the last glacial maximum (LGM). Our results revealed distinct spatial patterns of OC sources as indicated by n-alkane indicators in surface sediments. In the Western Ross Sea, n-alkanes predominantly originated from phytoplankton and bacteria, as evidenced by their unimodal distribution, low carbon preference index (CPI) of short-chain n-alkanes (CPIL = 1.41 ± 0.30), and low terrestrial/aquatic ratio (TAR = 0.22 ± 0.14). In the Southwest Ross Sea, n-alkanes were derived from marine algae and terrestrial bryophytes, indicated by bimodal distribution, low ratio of low/high molecular-weight n-alkanes (L/H = 0.62 ± 0.21), low CPI of long-chain n-alkanes (CPIH = 1.18 ± 0.16), and high TAR (1.26 ± 0.66). In contrast, the Eastern Ross Sea exhibited n-alkanes that were a combination of phytoplankton and dust from Antarctic soils and/or leaf waxes from mid-latitude higher plant, as suggested by both unimodal and bimodal distributions, high L/H (1.60 ± 0.58) and CPIH (2.04 ± 0.28), and medium TAR (0.61 ± 0.30). Geologically, during the LGM (27.3 -- 21.0 ka before present (BP)), there was an increased supply of terrestrial OC (TOC/TN = 13.63 ± 1.29, bimodal distribution of n-alkanes with main carbon peaks at nC17/nC19 and nC27). From 21.0 to 8.2 ka BP, as glaciers retreated and temperatures rose, the proportion of marine n-alkanes significantly increased (TOC/TN = 9.09 ± 1.82, bimodal distribution of n-alkanes with main carbon peaks at nC18/nC19 and nC25). From 8.2 ka BP to the present, as the ice shelf continued to retreat to its current position, the marine contribution became dominant (TOC/TN = 8.18 ± 0.51, unimodal distribution of n-alkanes with main carbon peak at nC17/nC18/nC19, and low TAR (0.41 ± 0.32)). This research has significant implications for understanding the variations in Antarctic OC sources and their climatic impacts in the context of accelerated glacier melting. [ABSTRACT FROM AUTHOR]

Most climate proxies of sea surface temperatures suffer from severe limitations when applied to cold temperatures that characterize Arctic environments. These limitations prevent us from constraining uncertainties for some of the most sensitive climate tipping points that can trigger rapid and dramatic global climate change such as Arctic/Polar Amplification, the disruption of the Atlantic Meridional Overturning Circulation, sea ice loss, and permafrost melting. Here, we present an approach to reconstructing sea surface temperatures globally using paired Mg/Ca - δ18Oc recorded in tests of the polar to subpolar planktonic foraminifera Neogloboquadrina pachyderma. We show that the fidelity of Mg/Ca-based paleoclimate reconstructions is compromised by variations in seawater carbonate chemistry which can be successfully quantified and isolated from paleotemperature reconstructions using a multiproxy approach. By applying the calibration to the last glacial maximum, we show that marine polar amplification has been underestimated by up to 3.0 ± 1.0 °C in model-based estimates. Standard climate proxies cannot quantify sea surface temperatures below 4 °C. Here, temperature signals recorded in shells (Mg/Ca) of polar foraminifera are isolated to resolve past marine polar amplification and climate change accurately. [ABSTRACT FROM AUTHOR]

This article discusses an algorithm called ArchPy that can analyze borehole data to determine the relative positions of geological units. The algorithm uses a matrix representation to track the relationships between units and applies rules to update the matrix based on the positions of adjacent units. It has been tested on synthetic and real data, showing promising results in accurately determining stratigraphic piles. However, the algorithm has limitations and alternative approaches are suggested to address them. Overall, the algorithm can be a valuable tool for determining stratigraphic sequences and aiding in geological data preprocessing. [Extracted from the article]

Phylogeographic studies have been conducted on many different mammal species in order to track their recent demographic histories. The climatic fluctuations associated with the Last Glacial Maximum (LGM) appear to have had a profound influence on the geographic patterning of genetic diversity in mammals. However, most phylogenetic studies have focused on single species. Few have used a holistic approach covering multiple taxa to explore common patterns. Here, we conducted meta-analyses of mitochondrial DNA control region sequences, identifying haplotype diversity and private allelic richness patterns in a geographic context. Four general patterns emerged among European mammals: an east–west decline in variation, a Western-Central belt of the highest diversity, southern richness, and homogeneity with no geographic pattern. These patterns likely reflect the refugial origins of modern populations. The east–west variation decline suggests species with eastern LGM refugia; the Western-Central belt of the highest diversity may harbor taxa with cryptic northern refugia, while southern richness may correspond to traditional southern refugia. Species with homogeneity and no geographic pattern may have been panmictic without a specific refugium or may reflect the occurrence of both southern and cryptic northern refugia. Surprisingly, the "no pattern" phenomenon is seldom discussed and may frequently have been discounted. Our study emphasizes the importance of considering multiple taxa, providing valuable insights into the responses of European mammals to past climatic changes. [ABSTRACT FROM AUTHOR]

Glacial periods have been considered as inhospitable environments that consist of treeless vegetation at higher latitudes. The fossil record suggests many species survived the Last Glacial Maximum within refugia, usually at lower latitudes. However, phylogeographic studies have given support to the existence of previously unknown high-latitude refugia that were not detected in the fossil record. Here, we test the hypothesis that cold-tolerant trees of Patagonia survived cold periods in microclimatically favourable locales where hybridization occurred between sister taxa. To study local presence through glacial periods in multiple refugia, we used pollen records and genetic information (isozymes, microsatellites, and combined nuclear and chloroplast DNA sequences) of population pairs of Nothofagus antarctica and N. pumilio that belong to the ancient subgenus Nothofagus which can potentially hybridize in nature, along their entire latitudinal range in Patagonia. Studied species share the N. dombeyi type pollen, which was abundant at >20% in the northernmost latitudinal bands (35–43°S), even during the Last Glacial Maximum. Mid- and southern latitudinal records (44–55°S) yielded lower abundances of ~10% that increased after c. 15.0 cal. ka BP. Therefore, fossil pollen evidence suggests a long-lasting local presence of Nothofagus throughout glacial–interglacial cycles but mostly as small populations between 44°S and 51°S. We found species-specific and shared genetic variants, the latter of which attained relatively high frequencies, thus providing evidence of ancestral polymorphisms. Populations of each species were similarly diverse, suggesting survival throughout the latitudinal range. Estimates of coalescent divergence times were broadly synchronous across latitudes, suggesting that regional climates similarly affected populations and species that hybridized through climate cycles, fostering local persistence. Graphical Abstract [ABSTRACT FROM AUTHOR]

Regional subsurface mapping of glacial depositional systems preserved in buried bedrock paleovalleys, and quantitative analysis of new LiDAR imagery of surface glacial landforms using machine learning techniques, when combined, are powerful tools for assessing the dynamics of the Laurentide Ice Sheet (LIS) during the last (Wisconsinan) glaciation in southern Ontario. While age dating of deposits preserved below Last Glacial Maximum tills (LGM: marine isotope stage (MIS) 2 < c.24 000 years B.P. (ybp)) is still sparse, newly available sedimentological data derived by cored drilling, combined with legacy outcrop data, identify thick (100 m+) successions of glaciolacustrine sediments and a lack of till(s), indicating that the ice sheet margin did not extend beyond the Niagara Escarpment at the western end of Lake Ontario, during the earliest phases of the glaciation (MIS 4) or the ensuing mid-Wisconsinan (MIS 3). Ice was able to extend into New York State blocking the Rome outlet to the Hudson Valley ponding deep proglacial lakes in the glacio-isostatically depressed Huron–Ontario–Erie basins recorded by thick glaciolacustrine sediments in paleovalleys. These were cannibalized by an expanding Late Wisconsinan ice sheet after ∼24 000 ybp recorded by extensive till sheets resting on a marked erosional unconformity, with drumlinized surfaces. Analysis and visualization of LiDAR data identifies discrete statistically validated flow sets of highly elongated streamlined bedforms (mega-scale glacial lineations (MSGLs)). These provide key evidence of a major reorganization of the ice sheet margin during deglaciation into lobate paleo ice streams shortly after 17 400 ybp. MSGLs are cut across earlier LGM drumlinized tills creating widespread "palimpsest" surfaces. At least two principal phases of fast ice flow can be identified, marked by large fluxes of sediment and the rapid building of large gravel and sand-dominated moraine complexes within interlobate depocentres, the largest glacial landforms in southern Ontario. Analysis of LiDAR data further reveals the common presence of DeGeer moraines where ice margins retreated in water, and iceberg scours. Future work using LiDAR mapping has the objective of fully documenting the number, extent, and timing of ice streams to enhance glaciological modelling when the ice sheet rapidly lost mass. [ABSTRACT FROM AUTHOR]

Both natural and anthropogenic forces can play a substantial role in the demographic history and current structure of a wildlife population. Species with strict habitat requirements are especially susceptible to these impacts. Mountain goats (Oreamnos americanus) in Alaska are of particular interest in this regard due to their influence on alpine ecosystems, importance to human cultures, and enigmatic history in some areas. Here, we used genetic tools to examine the population structure and demographic history of mountain goats in Alaska. We genotyped 816 mountain goats at 18 microsatellites, identified the number of genetically distinct subpopulations, and assessed their genetic diversity. We used Bayesian methods to investigate demographic history relative to the known geologic and human history of Alaska, and we simulated human-mediated translocation events onto islands to address the hypothesis that Baranof Island harbored an extant population prior to an early 20th-century introduction. We showed that Alaska has 4 genetically distinct subpopulations of mountain goats. The main demographic split between Southcentral and Southeast Alaska occurred following the retreat of ice after the Last Glacial Maximum. Simulations of translocation events largely aligned with expected genetic diversity patterns of current subpopulations except for Baranof Island which showed greater diversity than the simulation, consistent with the hypothesis of an endemic population prior to the translocation. This study highlights the value of considering both natural and anthropogenic forces when assessing the biogeographic history of a species and provides new insights about the complex demographic history and biogeography of mountain goats in Alaska. [ABSTRACT FROM AUTHOR]

Hydroclimate variation and vegetation changes of the Nile River watershed area in northeast Africa since the Last Glacial Maximum (LGM) were reconstructed based on n‐alkanes, their carbon isotope ratios (δ13Cn‐alkanes), and their hydrogen isotope ratios (δ2Hn‐alkanes) in sediments from ODP Site 967 in the Eastern Mediterranean Sea. The results were compared with the present vegetation cover in the watershed areas using ArcGIS. The average proportion of current grassland in the Equatorial Lake and Ethiopian Highland Plateaus watershed areas was 45.8 and 64.7%, respectively. δ2Hn‐alkanes ranged from −199 to −127‰ and co‐varied with insolation change response to orbital forcing. Depleted δ2Hn‐alkanes were found from deglaciation to the middle Holocene, suggesting increased precipitation during the African Humid Period (AHP) from 15 to 5 ka caused by northward migration of the Intertropical Convergence Zone. However, lower precipitation was inferred by enriched δ2Hn‐alkanes during the LGM and late Holocene. δ13Cn‐alkanes at Site 967 did not show a trend in harmony with δ2Hn‐alkanes and instead exhibited millennial‐scale variations ranging from –25.9 to –33.2‰. These δ13Cn‐alkanes values consistently indicated a C4 grass‐dominated environment in the watershed areas of the River Nile since the LGM, persisting through the AHP and into the present. Reconstructions demonstrated orbital and abrupt forcing of hydroclimate variability while maintaining generally grass‐dominated vegetation with weak precipitation feedback over the late Quaternary. [ABSTRACT FROM AUTHOR]

Knowledge of the population genetic structure and diversity of at-risk species is essential to accurately evaluate population viability and define units for conservation and management. The southeastern pocket gopher (Geomys pinetis) is a fossorial rodent native to the imperiled longleaf pine savannas of the southeastern United States. Its recent decline has made it a species of 'high conservation concern' by state agencies. Previous phylogenetic analyses suggested two distinct lineages within the species occurring east (G. p. pinetis) and west (G. p. mobilensis) of the Apalachicola-Chattahoochee-Flint River (ACF) Basin, a phylogeographic break for many species. However, little is known about the genetic substructure within each region. We examined neutral and putatively adaptive variation in 9373 single nucleotide polymorphisms (SNPs) to assess the extent of genetic structure across the species' geographic range. We confirmed significant genetic divergence of populations east–west of the ACF Basin, predating the Last Glacial Maximum, supporting the presence of two evolutionary independent lineages. Our results indicate additional strong genetic substructuring within each lineage and possible non-neutral variation across latitudes. Given the high degree of genetic differentiation and lack of evidence for secondary contact among populations within the ACF Basin, we recommend that G. pinetis be managed as two conservation units corresponding to distinct lineages representing G. pinetis and G. mobiliensis. [ABSTRACT FROM AUTHOR]

Species distributions are often indicative of historical biogeographical events and contemporary spatial biodiversity patterns. The Harlequin Duck Histrionicus histrionicus is a sea duck of conservation concern that has a disjunct distribution, with discrete portions of its range associated with northern Pacific and Atlantic Ocean basins. Movement data indicate migratory connectivity within regions of each ocean basin but not cross‐continent dispersal, suggesting that genetic structuring could exist at multiple spatial scales. Little is known regarding the impacts of past vicariance events on the species phylogeographical structure and historical demography, or rates of gene flow at different spatial scales. We used data from microsatellite loci and mitochondrial DNA (mtDNA) sequences to quantify levels of genetic diversity within, and the extent of spatial genetic differentiation among locations sampled at multiple spatial scales across the species range. Samples were collected at nonbreeding locations, which represent groupings appropriate for characterizing genetically differentiated subgroups at regional and continental scales. Collectively, genetic data and coalescence modelling suggested that individuals colonized regions currently occupied within both ocean basins in the Holocene from a single refuge in the Atlantic. Further, it seems likely there was secondary contact with lineages derived from populations in Asia, based on the shallow species‐wide mtDNA phylogeny and high incidence of recently derived private mtDNA haplotypes. Estimates of inter‐location variance in microsatellite allele and mtDNA haplotype frequency were moderate and significant between western (Pacific – North America) and eastern (Atlantic – North America, Greenland and Iceland) ocean basins and among sampling groups within each ocean basin. Genetic differentiation among sampling groups was particularly evident at the species distributional margins in the Atlantic (Iceland) and the Pacific (Shemya Island) Ocean basins. Coalescent modelling results suggest that contemporary spatial genetic patterns in the species arose through the combined influences of secondary contact, shared ancestry and gene flow after the last glacial maxima. [ABSTRACT FROM AUTHOR]

The biological aspects of infancy within late Upper Palaeolithic populations and the role of southern refugia at the end of the Last Glacial Maximum are not yet fully understood. This study presents a multidisciplinary, high temporal resolution investigation of an Upper Palaeolithic infant from Grotta delle Mura (Apulia, southern Italy) combining palaeogenomics, dental palaeohistology, spatially-resolved geochemical analyses, direct radiocarbon dating, and traditional anthropological studies. The skeletal remains of the infant – Le Mura 1 – were directly dated to 17,320-16,910 cal BP. The results portray a biological history of the infant's development, early life, health and death (estimated at ~72 weeks). They identify, several phenotypic traits and a potential congenital disease in the infant, the mother's low mobility during gestation, and a high level of endogamy. Furthermore, the genomic data indicates an early spread of the Villabruna-like components along the Italian peninsula, confirming a population turnover around the time of the Last Glacial Maximum, and highlighting a general reduction in genetic variability from northern to southern Italy. Overall, Le Mura 1 contributes to our better understanding of the early stages of life and the genetic puzzle in the Italian peninsula at the end of the Last Glacial Maximum. Here, the authors present paleogenomics, dental histology, geochemistry, radiocarbon dating, and bioarchaeological analysis of an Upper Palaeolithic infant from Grotta delle Mura (southern Italy). These data depict the health and development of the individual and point to regional population turnover at the time. [ABSTRACT FROM AUTHOR]

The biological aspects of infancy within late Upper Palaeolithic populations and the role of southern refugia at the end of the Last Glacial Maximum are not yet fully understood. This study presents a multidisciplinary, high temporal resolution investigation of an Upper Palaeolithic infant from Grotta delle Mura (Apulia, southern Italy) combining palaeogenomics, dental palaeohistology, spatially-resolved geochemical analyses, direct radiocarbon dating, and traditional anthropological studies. The skeletal remains of the infant – Le Mura 1 – were directly dated to 17,320-16,910 cal BP. The results portray a biological history of the infant's development, early life, health and death (estimated at ~72 weeks). They identify, several phenotypic traits and a potential congenital disease in the infant, the mother's low mobility during gestation, and a high level of endogamy. Furthermore, the genomic data indicates an early spread of the Villabruna-like components along the Italian peninsula, confirming a population turnover around the time of the Last Glacial Maximum, and highlighting a general reduction in genetic variability from northern to southern Italy. Overall, Le Mura 1 contributes to our better understanding of the early stages of life and the genetic puzzle in the Italian peninsula at the end of the Last Glacial Maximum. Here, the authors present paleogenomics, dental histology, geochemistry, radiocarbon dating, and bioarchaeological analysis of an Upper Palaeolithic infant from Grotta delle Mura (southern Italy). These data depict the health and development of the individual and point to regional population turnover at the time. [ABSTRACT FROM AUTHOR]

Understanding the causes of the ~90 ppmv atmospheric CO2 swings between glacial and interglacial climates is an important open challenge in paleoclimate research. Although the regularity of the glacial-interglacial cycles hints at a single driving mechanism, Earth System models require many independent physical and biological processes to explain the full observed CO2 signal. Here we show that biologically sequestered carbon in the ocean can explain an atmospheric CO2 change of 75 ± 40 ppmv, based on a mass balance calculation using published carbon isotopic measurements. An analysis of the carbon isotopic signatures of different water masses indicates similar regenerated carbon inventories at the Last Glacial Maximum and during the Holocene, requiring that the change in carbon storage was dominated by disequilibrium. We attribute the inferred change in carbon disequilibrium to expansion of sea-ice or change in the overturning circulation. Atmospheric CO2 was ~ 90 ppmv lower at the Last Glacial Maximum (LGM) than during the Holocene. Based on a carbon isotope budget, this study infers that at the LGM biological production pumped carbon into the deep ocean and sea ice kept it there. [ABSTRACT FROM AUTHOR]

The dynamics of the ice sheets on glacial timescales are highly controlled by interactions with the solid Earth, i.e., the glacial isostatic adjustment (GIA). Particularly at marine ice sheets, competing feedback mechanisms govern the migration of the ice sheet's grounding line (GL) and hence the ice sheet stability. For this study, we developed a coupling scheme and performed a suite of coupled ice sheet–solid Earth simulations over the last two glacial cycles. To represent ice sheet dynamics we apply the Parallel Ice Sheet Model (PISM), and to represent the solid Earth response we apply the 3D VIscoelastic Lithosphere and MAntle model (VILMA), which, in addition to load deformation and rotation changes, considers the gravitationally consistent redistribution of water (the sea-level equation). We decided on an offline coupling between the two model components. By convergence of trajectories of the Antarctic Ice Sheet deglaciation we determine optimal coupling time step and spatial resolution of the GIA model and compare patterns of inferred relative sea-level change since the Last Glacial Maximum with the results from previous studies. With our coupling setup we evaluate the relevance of feedback mechanisms for the glaciation and deglaciation phases in Antarctica considering different 3D Earth structures resulting in a range of load-response timescales. For rather long timescales, in a glacial climate associated with the far-field sea-level low stand, we find GL advance up to the edge of the continental shelf mainly in West Antarctica, dominated by a self-amplifying GIA feedback, which we call the "forebulge feedback". For the much shorter timescale of deglaciation, dominated by the marine ice sheet instability, our simulations suggest that the stabilizing sea-level feedback can significantly slow down GL retreat in the Ross sector, which is dominated by a very weak Earth structure (i.e., low mantle viscosity and thin lithosphere). This delaying effect prevents a Holocene GL retreat beyond its present-day position, which is discussed in the scientific community and supported by observational evidence at the Siple Coast and by previous model simulations. The applied coupled framework, PISM–VILMA, allows for defining restart states to run multiple sensitivity simulations from. It can be easily implemented in Earth system models (ESMs) and provides the tools to gain a better understanding of ice sheet stability on glacial timescales as well as in a warmer future climate. [ABSTRACT FROM AUTHOR]

We present 40 new 10 Be exposure ages of moraines and other glacial deposits left behind by the southeastern sector of the Laurentide Ice Sheet (LIS) in southern New England and New York, summarize the regional moraine record, and interpret the dataset in the context of previously published deglaciation chronologies. The regional moraine record spans the Last Glacial Maximum (LGM), with the outermost ridge of the terminal complex dating to ∼ 26–25 ka, the innermost ridge of the terminal complex dating to ∼ 22 ka, and a series of smaller recessional limits within ∼ 50 km of the terminal complex dating to ∼ 21–20.5 ka. The chronology generally agrees with independent age constraints from radiocarbon and glacial varves. A few inconsistencies between ages from cosmogenic-nuclide measurements and those from other dating methods are explained by geological scatter, where several bedrock samples and boulders from the outer terminal moraine exhibit nuclide inheritance, while some exposure ages of large moraines are likely affected by postdepositional disturbance. The exposure age chronology places the southeastern sector of the LIS at or near its maximum extent, from ∼ 26 to 21 ka, which is broadly consistent with the LGM sea-level lowstand, local and regional temperature indicators, and local summer insolation. The net change in LIS extent, represented by this chronology, occurred more slowly (< 5 to 25 m yr -1) than the subsequent retreat through the rest of New England, consistent with a slow general rise in insolation and modeled summer temperature. We conclude that the major pulse of LIS deglaciation and accelerated recession, recorded by dated glacial deposits north of the moraines discussed here, did not begin until after atmospheric CO 2 increased around 18 ka, marking the onset of Termination I. [ABSTRACT FROM AUTHOR]

During the Last Glacial Maximum (LGM), tidal dissipation was about 3-fold higher than today, which could have led to a considerable increase in vertical mixing. This increase might have enhanced the glacial Atlantic Meridional Overturning Circulation (AMOC), contradicting the shoaled AMOC indicated by paleoproxies. Here, we conduct ocean model simulations to investigate the impact of background climate conditions and tidal mixing on the AMOC during the LGM. We successfully reproduce the stratified ocean characteristics of the LGM by accurately simulating the elevated salinity of the deep sea and the rapid temperature decrease in the ocean's upper layers. Our findings indicate that the shoaled glacial AMOC is mainly due to strong glacial-ocean stratification, regardless of enhanced tidal dissipation. However, glacial tidal dissipation plays a critical role in the intensification of Antarctic Bottom Water (AABW) during the LGM. Given the critical role of the AMOC in (de-)glacial climate evolution, our results highlight the complex interactions of ocean stratification and tidal dissipation that have been neglected so far. [ABSTRACT FROM AUTHOR]

Pollen data represent one of the most widely available and spatially resolved sources of information about the past land cover and climate of the Last Glacial Maximum (LGM; 21 000 yr BP). Previous pollen data compilations for Europe, the Mediterranean, and the Middle East, however, have been limited by small numbers of sites and poor dating control. Here we present a new compilation of pollen data from the region that improves on both the number of sites (63) and the quality of the chronological control. Data were sourced from both public data archives and published (digitized) diagrams. The analysis is presented based on a standardized pollen taxonomy and sum, with maps shown for the major pollen taxa and biomes and the total arboreal pollen (AP), and on quantitative reconstructions of forest cover and of winter, summer, and annual temperatures and precipitation. The reconstructions are based on the modern analogue technique (MAT) adapted using plant functional type (PFT) scores and with a modern pollen dataset taken from the latest Eurasian Modern Pollen Database (EMPD) (∼8000 samples). A site-by-site comparison of the MAT and the inverse modelling method shows little or no significant difference between the methods for the LGM, indicating that the presence of low-CO 2 conditions and no modern analogue during the LGM does not appear to have had a major effect on MAT transfer function performance. Previous pollen-based climate reconstructions using modern pollen datasets show a much colder and drier climate for the LGM than both inverse modelling and climate model simulations do, but our new results suggest much greater agreement. Differences between our latest MAT reconstruction and those in earlier studies can largely be attributed to bias in the small modern dataset previously used and to differences in the method itself (Brewer et al., 2008; Salonen et al., 2019). We also find that quantitative forest cover reconstructions show more forest than previously suggested by biome reconstructions but less forest than suggested by simply the percentage of arboreal pollen, although uncertainties remain large. Overall, we find that LGM climatic cooling and drying were significantly greater in winter than in summer but with large site-to-site variance that emphasizes the importance of topography and other local factors in controlling the climate and vegetation of the LGM. [ABSTRACT FROM AUTHOR]

Understanding how population structure and demography are determined is a central theme in marine biogeography. While historical events, such as past climate change, are important determinants, the mechanisms by which they act are not well understood in many marine species. In this study, the population structure of the Japanese, marine intertidal gastropod Lunella correensis was investigated to determine whether it has been affected by past environmental changes. A genome-wide SNP analysis, L. correensis showed a genetic gradient along the coast and a weak genetic differentiation between sites in the Sea of Japan and the Pacific Ocean. Demographic inference suggests that the effective population size expanded and shrunk in response to periods of rapid warming and cooling due to past climate change. Further, ecological niche modelling suggests that the population size of L. correensis increased by advancing into the Sea of Japan during rapid warming after the Last Glacial Maximum. Notably, our analyses suggest that recent human activities may have influenced the effective population size of this species. Specifically, the period of reduction in the population size coincides with environmental changes and habitat loss associated with development along the Japanese coastal area. Thus, these results emphasize that the genetic structure and demography of marine species have been influenced by past environmental change around the Japanese Archipelago. [ABSTRACT FROM AUTHOR]

Aim: Temperature is regarded as an important driver of broad‐scale biodiversity patterns. However, less is known of the role of dispersal in shaping broad‐scale species and trait distributions, particularly given that species had to disperse out of glacial refugia after the Last Glacial Maximum (LGM). Here, we used a unique dataset describing the distributions of freshwater fauna combined with trait information to evaluate biodiversity relationships to distance to glacial refugia and temperature. Location: Twenty‐five biogeographical regions across Europe. Time Period: Data from species occurrence were gathered in 1978. Major Taxa Studied: A total of 2816 freshwater invertebrate species and 230 freshwater fish species. Methods: Using the occurrence of invertebrate and fish species in the biogeographical regions, and publicly available trait information, we analysed patterns in diversity indices (i.e. species richness, trait richness and trait redundancy), trait distribution and species and trait β‐diversity, and their relationship to distance to known glacial refugia and regional temperature. Results: We show that distributions of European invertebrate and fish species and traits are primarily explained by distance to refugia and its covarying effect with temperature (i.e. refugia tend to be warmer). Specifically, species and trait richness were higher in regions proximate to refugia and lower in distant regions. Additionally, communities in colder and distant regions exhibited reduced niche dimensions and slower life histories, suggesting increased vulnerability to environmental change. Main Conclusions: Species more distant from their refugia were characterized by higher dispersal capacities. Accordingly, since the LGM, only a subset of species was able to colonize distant regions, while many species have spatial ranges constrained by their dispersal capacity, increasing their potential for extinction under ongoing climate change. Therefore, additional conservation measures considering species' dispersal capacities are required. [ABSTRACT FROM AUTHOR]

The deterioration of natural habitats for oak species has steadily occurred as a consequence of both climate change and human pressure. Therefore, detailed and reliable information about the geographic distribution of oak species under changing climate conditions is needed for diverse ecological and conservation practices. This study examined the habitat suitability of endemic Kasnak oak, Quercus vulcanica Boiss. & Heldr. ex Kotschy, an endemic that ranges across the Central Anatolia Region and surrounding mountains in Türkiye. The occurrence data were gathered through fieldwork, and new records were identified. Next, we applied ecological niche modeling to assess the past, present-day, and future potential geographic range of the species in Anatolia. Projections for the Last Glacial Maximum indicate that most of the suitable areas for Kasnak oak were in southern Anatolia. However, present-day estimates suggest projections estimate suitable habitats in northern Anatolia and around the Anatolian Diagonal. According to future projections, the distribution of the species seems to decrease by 2100, with habitat suitability reduction ranging from 3.27% to 7.88%. Projections suggest a decrease in habitat suitability for the species, particularly in the western and southern Türkiye in the future. Moreover, the projections indicated that suitable habitats for the northern range of the species would likely persist until 2100, although they would diminish towards the northeast. The results can be effectively applied to enhance biodiversity conservation planning and management, leading to the development of innovative strategies. [ABSTRACT FROM AUTHOR]

Glacio-eustatic cycles lead to changes in sedimentation on all types of continental margins. There is, however, a paucity of sedimentation rate data over eustatic sea-level cycles in active subduction zones. During International Ocean Discovery Program Expedition 375, coring of the upper ∼110 m of the northern Hikurangi Trough Site U1520 recovered a turbidite-dominated succession deposited during the last ∼45 kyrs (Marine Isotope Stages (MIS) 1–3). We present an age model integrating radiocarbon dates, tephrochronology, and δ18O stratigraphy, to evaluate the bed recurrence interval (RI) and sediment accumulation rate (SAR). Our analyses indicate mean bed RI varies from ∼322 yrs in MIS1, ∼49 yrs in MIS2, and ∼231 yrs in MIS3. Large (6-fold) and abrupt variations in SAR are recorded across MIS transitions, with rates of up to ∼10 m/kyr occurring during the Last Glacial Maximum (LGM), and <1 m/kyr during MIS1 and 3. The pronounced variability in SAR, with extremely high rates during the LGM, even for a subduction zone, are the result of changes in regional sediment supply associated with climate-driven changes in terrestrial catchment erosion, and critical thresholds of eustatic sea-level change altering the degree of sediment bypassing the continental shelf and slope via submarine canyon systems. [ABSTRACT FROM AUTHOR]

New biostratigraphically constrained chronologies have been developed to help elucidate the sedimentary and tectonic history of Quaternary sequences on the Hikurangi margin of north-eastern Zealandia. Three sites on the mid to lower slope of the accretionary prism (IODP Site 372-U1517, 375-U1519, 375-U1518) and two sites east of the deformation front (Hikurangi Trough Site 375-U1520 and Tūranganui Seamount Site 375-U1526) are dated using a detailed biostratigraphic framework based on planktic foraminiferal records from ODP Site 181-1123. The dating indicates sedimentation rates are very high and variable on the accretionary prism (0.2–9.6 m/kyr), especially during the Last Glacial Maximum (LGM) when downslope redeposition from the continental shelf and upper slope is common. Sedimentation rates at Hikurangi Trough Site 375-U1520 are also variable (0.01–3.0 m/kyr) and they increase markedly as the incoming site approached the deformation front, especially during the LGM, due to an abundance of downslope redeposition from the inner to mid shelf. The incoming Quaternary section at Tūranganui Seamount Site 375-U1526, is punctuated by hiatuses that shorten in duration as the site approached the deformation front, whilst sedimentation rates remain relatively low (0.04–0.4 m/kyr). [ABSTRACT FROM AUTHOR]

Species conservation can be improved by knowledge of genetic diversity and demographic history. The Sichuan hill-partridge (Arborophila rufipectus , SP) is an endangered species endemic to the mountains in southwestern China. However, little is known about this species' genomic variation and demographic history. Here, we present a comprehensive whole-genome analysis of six SP individuals from the Laojunshan National Nature Reserve in Sichuan Province, China. We observe a relatively high genetic diversity and low level of recent inbreeding in the studied SP individuals. This suggests that the current population carries genetic variability that may benefit the long-term survival of this species, and that the present population may be larger than currently recognized. Analyses of demographic history showed that fluctuations in the effective population size of SP are inconsistent with changes of the historical climate. Strikingly, evidence from demographic modeling suggests SPs population decreased dramatically 15,100 years ago after the Last Glacial Maximum, possibly due to refugial isolation and later human interference. These results provide the first detailed and comprehensive genomic insights into genetic diversity, genomic inbreeding levels, and demographic history of the Sichuan hill-partridge, which are crucial for the conservation and management of this endangered species. [ABSTRACT FROM AUTHOR]

Aim: In northern environments, periods of isolation during Pleistocene glaciations and subsequent recolonization and secondary contact have had a significant influence on contemporary diversity of many species. The recent advent of high‐resolution genomic analyses allows unprecedented power to resolve genomic signatures of such events in northern species. Here, we provide the highest resolution genomic characterization of Atlantic salmon in North America to date to infer glacial refugia and the geographic scales of post‐glacial secondary contact. Location: North America. Taxon: Atlantic salmon, Salmo salar. Methods: Samples were collected for 5455 individuals from 148 populations, encompassing the majority of the Atlantic salmon's native range in North America, from Labrador to Maine. Individuals were genotyped using a 220K single nucleotide polymorphism array aligned to the Atlantic salmon (Salmo salar) genome. Spatial genetic structure (principal component analysis, k‐means clustering, admixture) was evaluated in conjunction with genomic comparisons of these identified lineages to infer the refugia during the last glacial maximum and regions of secondary contact following recolonization. Results: Spatial genomic analyses identified three phylogeographic groups, consistent with the northward recolonization from two southern glacial refugia in North America (a western Maritime lineage and an eastern Newfoundland and Labrador lineage), with subsequent differentiation of the eastern lineage into two separate groups. Secondary contact among these North American groups was observed within the northern Gulf of St. Lawrence, and evidence of trans‐Atlantic secondary contact was detected within the eastern Newfoundland and Labrador lineage. Comparison of groups from insular Newfoundland with those from mainland Labrador suggests genomic regions displaying high differentiation were characterized by elevated European admixture, suggesting a possible role of European secondary contact in population divergence. Main Conclusions: These findings present the first evidence suggesting that genomic diversity in extant North American Atlantic salmon populations has resulted from allopatric isolation in two glacial refugia followed by both regional and trans‐Atlantic recolonization and secondary contact and demonstrate the power of genomic tools to resolve historical drivers of diversity in wild populations. [ABSTRACT FROM AUTHOR]

Aim: Reproductive systems strongly influence plants' evolution and adaption, and the biogeographic pattern of its variation has intrigued biologists and ecologists. Here, to test the impacts of paleoglaciation on plants' reproductive system variation, we compared the geographical pattern and environmental drivers in the proportions of different reproductive systems in Primula in regions affected and unaffected by paleoglaciation. Location: Global. Time Period: Since the Last Glacial Maximum (LGM). Major Taxa Studied: Primula. Methods: Using data on reproductive systems and distributions of 604 Primula taxa around the world and 221 along the elevational gradient of the Himalayas, we demonstrated the global pattern and the elevational pattern in the proportions of homostylous taxa. We employed general linear models to establish the relationship between the proportion of homostylous taxa and environmental variables and hierarchical partitioning to assess the relative contributions of these variables in both regions affected and unaffected by paleoglaciation, respectively. Results: We found a higher proportion of homostylous taxa in regions glaciated during the LGM than those unglaciated, with different latitudinal patterns and climate drivers. The proportion of homostylous taxa showed varying trends across different regions: increasing with latitude and temperature anomaly in glaciated regions while concentrating at lower latitudes with higher winter temperatures in unglaciated regions. Additionally, homostylous taxa were more prevalent at lower elevations in the Himalayas. Main Conclusions: Our study provides the first quantitative evidence for the hypothesis that selfers are more prevailing in regions affected by paleoglaciation facilitated by recolonization via comparing the geographic pattern and drivers in regions affected and unaffected by paleoglaciation. Our findings also reveal the concentrated distribution of homostylous taxa in Primula at low latitudes, which may be the result of population shrinkage caused by heat stress, facing a more severe survival crisis under the circumstances of global warming and increasing human activities. [ABSTRACT FROM AUTHOR]

Aim: Various species distributed in the Alps have their disjunct occurrences in the Carpathians. Fossil evidence for some woodland snails of Alpine distribution suggests that they colonized the Carpathians during the Holocene forest optimum or later. Here, we focus on disjunct Carpathian populations of the rock‐dwelling alpine snail Pyramidula saxatilis. As it occupies very stable habitats, that is, high‐elevation limestone rocks, one can assume its potential survival in Carpathian refugia over the glacial period(s). For comparison, the more widespread and warm‐climate P. pusilla is analysed. Location: Europe. Taxon: Pyramidula saxatilis and P. pusilla. Methods: We analysed the genetic diversity of P. saxatilis and P. pusilla populations across their entire ranges using mitochondrial DNA and nuclear DNA markers. Seven fossil mollusc successions from the area where P. saxatilis occurs in the Carpathians were analysed and dated using the radiocarbon method. Habitat suitability models of both species were calculated for selected time periods since the Last Glacial Maximum. Results: All Carpathian P. saxatilis populations were genetically homogeneous and similar to those from the Eastern Alps. In P. pusilla, we found a genetically distinct lineage in the southern Western Carpathians. Both species were found in three fossil profiles since the Middle Holocene, and in one already in the Late Glacial. Habitat suitability models suggested the fluctuations of suitable conditions in the Carpathians driven by summer precipitation, especially for P. saxatilis. Main Conclusions: Our results suggest that the Carpathian populations of P. saxatilis represent a post‐LGM colonization from the Eastern Alps triggered by climatic changes, mainly by the increase in summer precipitation during the Late Glacial interstadials and Middle Holocene. The evidence for P. pusilla is similar, but also suggests rare long‐term survival in the Carpathian microrefugia. The palaeoecological evidence indicates a possible threat to high‐elevation species from future fluctuations in precipitation regimes. [ABSTRACT FROM AUTHOR]

Coccoloba uvifera L. (seagrape) is a primarily dioecious neotropical tree species which often grows in the beach–forest transitional ecotone of coastal strand vegetation. We used five maternally inherited non-coding chloroplast regions to characterize the phytogeography of C. uvifera collected across the Caribbean Basin and Florida. Bayesian analysis revealed divergence between the Aruba–Trinidad–Tobago–Antigua–Jamaica island group and the continental Belize–Florida–US Virgin Islands (USVI) group at 1.78 million years before present (mybp), divergence between the Belize and Florida–USVI groups at 1.08 mybp, and a split of Antigua–Jamaica from Aruba–Trinidad–Tobago at 0.217 mybp. Haplotype network analysis supports the three clades, with the island group possessing the oldest haplotype. Based on geology and proximity, these clades correspond to South American (oldest), Central American, and North American (most recent). Coccoloba uvifera demographic expansion occurred during the Pleistocene epoch and peaked near the end of the last glacial maximum (ca. 0.026–0.019 mybp) when the global sea levels were 125 m lower than today. Our findings also reveal that tropical cyclones, which often impact coastal strand vegetation, did not affect genetic diversity. However, there was a positive association between latitude and the average number of substitutions, further enriching our understanding of the species' phytogeography. [ABSTRACT FROM AUTHOR]

Modern humans have experienced explosive population growth in the past thousand years. We hypothesized that recent human populations have inhabited environments with relaxation of selective constraints, possibly due to the more abundant food supply after the Last Glacial Maximum. The ratio of nonsynonymous to synonymous mutations (N/S ratio) is a useful and common statistic for measuring selective constraints. In this study, we reconstructed a high-resolution phylogenetic tree using a total of 26,419 East Eurasian mitochondrial DNA genomes, which were further classified into expansion and nonexpansion groups on the basis of the frequencies of their founder lineages. We observed a much higher N/S ratio in the expansion group, especially for nonsynonymous mutations with moderately deleterious effects, indicating a weaker effect of purifying selection in the expanded clades. However, this observation on N/S ratio was unlikely in computer simulations where all individuals were under the same selective constraints. Thus, we argue that the expanded populations were subjected to weaker selective constraints than the nonexpanded populations were. The mildly deleterious mutations were retained during population expansion, which could have a profound impact on present-day disease patterns. [ABSTRACT FROM AUTHOR]

Rapid anthropogenic climate change has elevated the interest in studying the biotic responses of species during the Last Glacial Maximum. During this period, species retreated to highly spatially restricted geographic regions where survival was possible, known as glacial micro-refugia, from which they migrated and expanded when conditions became more suitable. Several distinct sources of evidence have contributed to developing a new understanding of how these regions might have impacted the sustainability of the natural populations of many species. Pollen records in Eastern Beringia have been used to explore the possibility that the region harbored glacial refugia for several plants from the arctic tundra and/or the boreal forest biomes common to the region. Our study focuses on Alnus viridis and Picea glauca, two predominant species of arcto-boreal vegetation. We propose to integrate genomic, SDM, and existing fossil data in a hierarchical Bayesian modeling (HBM) framework to determine whether multiple refugia existed in isolated geographic areas. This study demonstrates how the flexibility of HBMs makes the formal synthesis of such disparate data sources feasible. Our results highlight the regions of plausible refugia that can guide future investigations into studying the role of glacial refugia during climate change. Supplementary materials accompanying this paper appear online. [ABSTRACT FROM AUTHOR]

Any experiment with climate models relies on a potentially large set of spatio-temporal boundary conditions. These can represent both the initial state of the system and/or forcings driving the model output throughout the experiment. These boundary conditions are typically fixed using available reconstructions in climate modeling studies; however, in reality they are highly uncertain, that uncertainty is unquantified, and the effect on the output of the experiment can be considerable. We develop efficient quantification of these uncertainties that combines relevant data from multiple models and observations. Starting from the coexchangeability model, we develop a coexchangeable process model to capture multiple correlated spatio-temporal fields of variables. We demonstrate that further exchangeability judgments over the parameters within this representation lead to a Bayes linear analogy of a hierarchical model. We use the framework to provide a joint reconstruction of sea-surface temperature and sea-ice concentration boundary conditions at the last glacial maximum (23–19 kya) and use it to force an ensemble of ice-sheet simulations using the FAMOUS-Ice coupled atmosphere and ice-sheet model. We demonstrate that existing boundary conditions typically used in these experiments are implausible given our uncertainties and demonstrate the impact of using more plausible boundary conditions on ice-sheet simulation. for this article are available online, including a standardized description of the materials available for reproducing the work. [ABSTRACT FROM AUTHOR]

Climatic changes can affect species distributions, population abundance, and evolution. Such organismal responses could be determined by the amount and quality of available habitats, which can vary independently. In this study, we assessed changes in habitat quantity and quality independently to generate explicit predictions of the species' responses to climatic changes between Last Glacial Maximum (LGM) and present day. We built ecological niche models for genetic groups within 21 reptile, mammal, and plant taxa from the Baja California peninsula inhabiting lowland or highland environments. Significant niche divergence was detected for all clades within species, along with significant differences in the niche breadth and area of distribution between northern and southern clades. We quantified habitat quantity from the distribution models, and most clades showed a reduction in distribution area towards LGM. Further, niche marginality (used as a measure of habitat quality) was higher during LGM for most clades, except for northern highland species. Our results suggest that changes in habitat quantity and quality can affect organismal responses independently. This allows the prediction of genomic signatures associated with changes in effective population size and selection pressure that could be explicitly tested from our models. [ABSTRACT FROM AUTHOR]

The Caatinga is the largest patch of Seasonal Dry Tropical Forest in the Neotropics, located in northeastern Brazil and characterized mainly by deciduous vegetation and extreme rainfall seasonality. It has historically been treated as a biologically impoverished domain, but recent studies uncovered new diversification patterns and several new taxa of frogs, mammals, insects, and fishes. Here we employed a dense sampling regime to evaluate whether the São Francisco River (SFR) would have promoted genetic diversification and fixed phenotypic differences and how Quaternary climatic oscillations shaped distribution and population sizes in a Caatinga endemic species, the Silvery‐cheeked Antshrike (Sakesphoroides cristatus). We adopted an integrative approach using multilocus genetic, plumage, vocal data, and ecological niche modelling (ENM) to characterize evolutionary units and niche suitability in past scenarios. We recovered strong genetic structure across the SFR that was congruent with plumage and vocal variation, revealing a yet undescribed species named herein as Sakesphoroides niedeguidonae, sp. nov. (urn:lsid:zoobank.org:act:2B9FC637‐008A‐4E9A‐B92B‐69ED7FE23823s). The splitting time estimated between the newly described species and S. cristatus is consistent with the establishment of the modern course of SFR, with a more recent course shift apparently promoting the secondary contact between the two species in the Raso da Catarina region. After their split, both species experienced increases in population sizes and range sizes at similar times during the Last Glacial Maximum. We expect other Caatinga avian endemic lineages to show similar patterns of genetic differentiation across the SFR that were enhanced by Quaternary climatic oscillations. [ABSTRACT FROM AUTHOR]

The Indian Central Himalaya Region (ICHR), the northern topographic front of the Indian summer monsoon (ISM), is an ideal location to study topography-climate interactions because two weather systems—the ISM and mid-latitude westerlies (MLW)—create distinct eco-climatic regimes from tundra (north) to tropical (south). The region's paleoclimatic studies show considerable climatic variations since the late Pleistocene. We evaluated 29 paleoclimatic records from the region and synthesized the results semi-quantitatively using the weighted palaeoclimate index (WApCI) to better understand the important climatic events and their driving mechanisms. According to the WApCI, the region has at least six enhanced monsoonal periods and eight drier spells during the past 34 ka. The cold-dry climatic events, such as the last glacial maxima (LGM), Younger Dryas (YD), 8.2 ka, and 4.2 ka, are associated with northern-hemisphere (NH) climate dynamics and propagated via MLWs. While, the warmer phases are dictated by the insolation-driven ISM dynamics. The WApCI's reconstructed rainfall anomaly aligns with paleoclimatic-model experiments for dynamically generated Paleoclimate Modeling Intercomparison Projects (PMIP3/PMIP4) rainfall for chosen time-slices (last-millenium, historical, mid-Holocene, and LGM). Finally, the Granger causality test determines the temporal relationship between the climatic drivers/forcing indices and primary meteorological parameters. The results showed that summer and post-monsoon precipitation is primarily influenced by total solar irradiation, winter precipitation is driven by a complex mix of variables, and pre-monsoon precipitation is driven by the Arctic oscillation. Based on the facts, we hypothesize that past climate variability demonstrates a complex interplay of local and hemisphere teleconnections in ICHR's climate dynamics. [ABSTRACT FROM AUTHOR]

Chile’s Torres del Paine National Park (TPNP) is one of the most impressive landscapes in southern Patagonia, with unique natural elements on the edge of the southern ice field, where knowledge of soils and ecological relationships is nonexistent. Therefore, the objective of this study was to determine the chemical, physical, mineralogical, and micromorphological characteristics of Holocene soils along a local toposequence representing the main vegetation types of the TPNP. The morphological, chemical, physical, and mineralogical properties of 12 soil profiles were studied and classified according to Soil Taxonomy. Coevolution of vegetation and soil taxa is clearly evident since glaciation, with podsolization under austral Nothofagus pumilio forests leading to the development of spodosols, while paludization in local depressions with Nothofagus forests allowed the formation of histosols. Slopes covered with loess and tephra led to the formation of Andisols with shrub vegetation. Predominant parent materials include till from Late Quaternary advances of southern Andean ice, Pleistocene loess, and volcanic ash from surrounding Chilean volcanoes. The parent materials were strongly influenced by Late Quaternary climatic and landscape changes following the retreat of the Last Glacial Maximum in southern Patagonia, resulting in erosional and depositional conditions (windblown loess, fluvial glacial deposits, and moraines). Stable landforms show the influence of allochthonous volcanic ash shaping Andean features, combined with the accumulation of organic matter in hydromorphic soils. Three main groups of soils have been identified: loess-rich soils, organic-rich soils, and poorly developed soils. The latter show low fertility related to recent landforms on different substrates ranging from till, rocky slopes, talus, or glacial deposits. In high mountain regions under periglacial conditions, cryoturbation features indicate seasonal frost–thaw cycles without current permafrost. The diversity of soil orders in the mountains of southern Patagonia is comparable to similar environmental conditions and latitudes in the Northern Hemisphere. However, the andic properties due to volcanic ejecta inputs, as well as organic-rich soils at low altitudes of bottom valleys, are typical features of the soils at TNTP. [ABSTRACT FROM AUTHOR]

Simple Summary: Hydrocera triflora is primarily distributed across southeastern and southern Asia and is classified as endangered within China. The impact of climate change on the spatial distribution of this species remains uncertain. In this study, we employed the MaxEnt model to examine the migration patterns of H. triflora under the influence of climate change. Our findings indicate that the current potential distribution area is more extensive than during the three historical periods analyzed. Furthermore, projections suggest that the potential habitable area for H. triflora will continue to expand to higher altitudes by the year 2100. It is advised that protected areas be established within the current core distribution regions. Concurrently, public awareness and educational initiatives should be enhanced to mitigate the impact of human activities on wild populations. Strengthening the conservation of wild resources is imperative. Hydrocera triflora is a perennial herb found in southeastern and southern Asia. In China, it is only found in Hainan Province. With global climate change, studying the impact of climate change on the distribution of H. triflora can provide a theoretical basis for the scientific protection of this species. In this study, the MaxEnt model was used to predict the potential distribution area of H. triflora in China under historical, current, and future periods based on 66 distribution points and 12 environmental variables. The results were as follows: (i) The main environmental variables affecting the distribution of H. triflora were precipitation in the coldest month and in the wettest quarter, with elevation also being a significant factor. (ii) Over the past three periods, the last interglacial, last glacial maximum, and mid-Holocene, the suitable area for H. triflora initially decreased and then increased. The suitable area reached the lowest value in the last glacial maximum period, at only 27.03 × 104 km2. (iii) The current potential distribution area is 67.81 × 104 km2, and the optimal area is mainly distributed in the Guangxi, Guangdong, and Hainan provinces. (iv) Under future climate scenarios, the potential distribution area of H. triflora is projected to increase by 11.27~90.83 × 104 km2. It is expected to reach a maximum value (158.64 × 104 km2) in 2081~2100 under the SSP-585 climate scenario, with the distribution centroid shifting to higher latitudes. The newly gained optimal habitats will provide potential areas for introduction and ex situ conservation of this species. [ABSTRACT FROM AUTHOR]

The last deglaciation experienced the retreat of massive ice sheets and a transition from the cold Last Glacial Maximum to the warmer Holocene. Key simulation challenges for this period include the timing and extent of ice sheet decay and meltwater input into the oceans. Here, major uncertainties and forcing factors for the last deglaciation are evaluated. Two sets of transient simulations are performed based on the novel ice‐sheet reconstruction PaleoMist and the more established GLAC1D. The simulations reveal that the proximity of the Atlantic meridional overturning circulation (AMOC) to a bifurcation point, where it can switch between on‐ and off‐modes, is primarily determined by the interplay of greenhouse gas concentrations, orbital forcing and freshwater forcing. The PaleoMist simulation qualitatively replicates the Bølling‐Allerød (BA)/Younger Dryas (YD) sequence: a warming in Greenland and Antarctica during the BA, followed by a cooling northern North Atlantic and an Antarctic warming during the YD. Plain Language Summary: The last deglaciation, spanning roughly 20,000 to 10,000 years ago, marked a period of Earth's history characterized by the retreat of massive ice sheets that had covered large parts of the planet. During this phase, a drastic transition occurred from the cold Last Glacial Maximum to the warmer and more stable climate of the Holocene. A main challenge for simulating the last deglaciation is the timing and amplitude of the ice sheet decay and the amount of meltwater that enters into the oceans. Using two different reconstructions of ice sheets, we employ an efficient climate model to explore changes at the end of the last ice age. Our comparison shows notable differences in the timing and amplitude of abrupt climate events in the simulations using two different ice‐sheet reconstructions. Furthermore, we investigate the effects of factors such as greenhouse gases and Earth's orbital changes on the large‐scale ocean currents with respect to underlying ice sheets. Ultimately, our study sheds light on how different elements of the Earth's system shape the termination of the last ice age, enriching our understanding of Earth's climate history and guiding further deglaciation scenarios. Key Points: Transient simulations of the last deglaciation using GLAC1D and the new PaleoMist ice sheet reconstruction are compared for the first timeAMOC stability is impacted by ice sheet reconstruction used and the combination of forcings, indicating its proximity to a bifurcation pointPaleoMist simulation captures the BA/YD sequence signature in the northern North Atlantic [ABSTRACT FROM AUTHOR]

We investigate the position and intensity changes of the Intertropical Convergence Zone (ITCZ) over Asia (50°E−135°E) relative to the preindustrial period annually and seasonally during the Last Interglacial (LIG), Last Glacial Maximum (LGM), and mid‐Holocene (MH) using available models from phases 3 and 4 of the Paleoclimate Modeling Intercomparison Project. The multi‐model mean shows that the June–July–August ITCZ variations generally dominate the annual changes. The Asian ITCZ shifts northward over western Asia and southward over the eastern side in both the LIG and MH, and the opposite occurs in the LGM. Its intensity varies with longitude similarly for the LIG and MH and generally weakens in the LGM. Precipitation changes associated directly with ITCZ indices are primarily caused by the dynamic term in the LIG and MH, while both dynamic and thermodynamic terms play roles in the LGM, with major contributions from the convergence components. Plain Language Summary: As an intense rain belt, the Intertropical Convergence Zone (ITCZ) has an important influence on the regional climate, particularly over Asia. However, its future and past behaviors remain unclear. Based on multi‐model experiments, we investigate Asian ITCZ changes in location and intensity during the past three typical periods: the interglacial periods of the Last Interglacial and the mid‐Holocene and the glacial period of the Last Glacial Maximum. The Asian ITCZ overall strengthens and regionally moves northward over the western part and southward over the eastern part during the two interglacial periods relative to its preindustrial state, which are generally opposite to the position and intensity changes in the glacial period. These ITCZ changes are directly caused by uneven precipitation changes, which are dominated by atmospheric circulation changes during interglacial periods and additionally contributed from water vapor content changes during glacial periods, primarily through the vertical motion of air. Key Points: Asian Intertropical Convergence Zone (ITCZ) shifts northward over western Asia and southward over the eastern side in Last Interglacial (LIG) and mid‐Holocene (MH), and the opposite occurs in Last Glacial Maximum (LGM)Asian ITCZ intensity varies with longitude similarly for LIG and MH, while it weakens during LGMDynamic term dominates the ITCZ‐related precipitation changes in LIG and MH, while both dynamic and thermodynamic terms play roles in LGM [ABSTRACT FROM AUTHOR]

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Cyclobalanopsis gilva, a valuable timber species in China, holds significant importance for understanding the constraints imposed by climate change on the dynamic geographic distribution of tree species. This study utilized the MaxEnt maximum entropy model to reconstruct the migratory dynamics of C. gilva geographical distribution since the Last Glacial Maximum. The objective was to comprehend the restrictive mechanisms of environmental factors on its potential geographical distribution, aiming to provide insights for mid-to-long-term afforestation planning of C. gilva. The optimized MaxEnt model exhibited a significantly high predictive accuracy, with an average AUC value of 0.949 ± 0.004 for the modern suitable habitat model of C. gilva. The total suitable habitat area for C. gilva in contemporary times was 143.05 × 104 km2, with a highly suitable habitat area of 3.14 × 104 km2. The contemporary suitable habitat was primarily located in the southeastern regions of China, while the highly suitable habitat was concentrated in eastern Fujian and central-eastern Taiwan. Bioclimatic variables such as mean diurnal range (Bio2), min temperature of coldest month (Bio6), precipitation of driest quarter (Bio17), and precipitation of driest month (Bio14) predominantly influenced the modern geographic distribution pattern of C. gilva, with temperature factors playing a leading role. With global climate warming, there is a risk of fragmentation or even loss of suitable habitat for C. gilva by 2050 and 2090. Therefore, the findings of this study can significantly contribute to initiating a habitat conservation campaign for this species. [ABSTRACT FROM AUTHOR]

The last glacial period is known to have greatly influenced the demographic history of temperate forest trees, with important range contractions and post‐glacial expansions that led to the formation of multiple genetic lineages and secondary contact zones in the Northern Hemisphere. These dynamics have been extensively studied for European and North American species but are still poorly understood in other temperate regions of rich biodiversity such as the Caucasus. Our study helps filling that gap by deciphering the genomic landscapes of F. orientalis across the South Caucasus. The use of genome‐wide data confirmed a past demographic history strongly influenced by the Last Glacial Maximum, revealing two disjunct glacial refugia in the Colchis and Hyrcanian regions. The resulting patterns of genetic diversity, load and differentiation are not always concordant across the region, with genetic load pinpointing the location of the glacial refugia more efficiently than genetic diversity alone. The Hyrcanian forests show depleted genetic diversity and substantial isolation, even if long‐distance gene flow is still present with the main centre of diversity in the Greater Caucasus. Finally, we characterize a strong heterogeneity of genetic diversity and differentiation along the species chromosomes, with noticeably a first chromosome showing low diversity and weak differentiation. [ABSTRACT FROM AUTHOR]

Inbreeding, the mating of individuals that are related through common ancestry, is of central importance in evolutionary and conservation biology due to its impacts on individual fitness and population dynamics. However, while advanced genomic approaches have revolutionised the study of inbreeding in animals, genomic studies of inbreeding are rare in plants and lacking in fungi. We investigated global patterns of inbreeding in the prized edible porcini mushroom Boletus edulis using 225 whole genomes from seven lineages distributed across the northern hemisphere. Genomic inbreeding was quantified using runs of homozygosity (ROHs). We found appreciable variation both among and within lineages, with some individuals having over 20% of their genomes in ROHs. Much of this variation could be explained by a combination of elevation and latitude, and to a lesser extent by predicted habitat suitability during the last glacial maximum. In line with this, the majority of ROHs were short, reflecting ancient common ancestry dating back approximately 200–1700 generations ago, while longer ROHs indicative of recent common ancestry (less than approximately 50 generations ago) were infrequent. Our study reveals the inbreeding legacy of major climatic events in a widely distributed forest mutualist, aligning with prevailing theories and empirical studies of the impacts of historical glaciation events on the dominant forest tree species of the northern hemisphere. [ABSTRACT FROM AUTHOR]

Ice sheet feedbacks are underrepresented in model assessments of climate sensitivity and their magnitudes are still poorly constrained. We combine a recently published record of Earth's Energy Imbalance (EEI) with existing reconstructions of temperature, atmospheric composition, and sea level to estimate both the magnitude and timescale of the ice sheet‐albedo feedback since the Last Glacial Maximum. This facilitates the first opportunity to quantify this feedback over the most recent deglaciation using a proxy data‐driven approach. We find the ice sheet‐albedo feedback to be amplifying, increasing the total climate feedback parameter by 42% and reaching an equilibrium magnitude of 0.55 Wm−2K−1, with a 66% confidence interval of 0.45–0.63 Wm−2K−1. The timescale to equilibrium is estimated as 3.6 ka (66% confidence: 1.9–5.5 ka). These results provide new evidence for the timescale and magnitude of the amplifying ice sheet‐albedo feedback that will drive anthropogenic warming for millennia to come. Plain Language Summary: During a deglacial transition, ice sheets melt and retreat, decreasing the reflectivity of the land surface and increasing the surface temperature, leading to further melting. It is agreed that this feedback amplifies global warming on millennial timescales, but the exact magnitude and timescale are still very uncertain. This is important because the stronger the feedback, the more sensitive Earth's climate is to carbon dioxide on long timescales. We use proxy data records of the past 25,000 years to quantify the ice sheet‐albedo feedback since the Last Glacial Maximum and estimate the time taken for the feedback to reach equilibrium and stabilize. We find that the ice sheet‐albedo feedback strongly amplifies warming over thousands of years, increasing our understanding of how human activity today will continue to influence our climate for generations into the future. Key Points: Novel proxy data‐driven assessment of the ice sheet‐albedo feedback for the last deglaciation is presentedIce sheet‐albedo feedback is amplifying during a deglacial transition with a best estimate of 0.55 Wm−2K−1 (0.45–0.63 Wm−2K−1)Ice sheet‐albedo feedback reaches equilibrium after approximately 3.6 ka (1.9–5.5 ka) [ABSTRACT FROM AUTHOR]

The article focuses on challenging the validity of geomorphic markers and dating methods used in a previous study of fault slip rates along the Magallanes Fault System in Tierra del Fuego, Patagonia. It critiques the suitability of the markers selected and the robustness of the dating techniques applied, arguing that the conclusions drawn from the original study may be unreliable due to these methodological issues.

Under the background of global climate change, the evolution of climate in the future is the focus of geoscience. The Nanri Channel is an important passage connecting the Xinghua Bay and the Taiwan Strait, in China, and the study of its provenance and paleoenvironmental alternation is of great significance to the climate evolution in the eastern coast of China. The grain size and X-ray diffraction analyses of sediments from ZK1 in Nanri Channel and ZK5 in Xinghua Bay, were used to study the variation of grain size and clay mineral characteristics and to analyze the changes in hydrodynamic characteristics, provenance, and paleoenvironmental evolution in the regions since the Last Glacial Maximum. The results show that the sedimentary environment of ZK1 varies from the nearshore tidal flat facies with strong hydrodynamic conditions and the neighboring rivers as the main provenance, to the littoral facies with weak hydrodynamic conditions and the Yangtze River-like type sediments as the main provenance. The sedimentary environment of ZK5 is from the nearshore tidal flat facies with strong hydrodynamic conditions to the littoral facies with weak hydrodynamic conditions, and the provenance of both facies is mainly Yangtze River-like type sediments. The clay mineral characteristics of ZK1 show that the climate in the Nanri Channel has experienced a change from cool and wet, to mild and dry, to mild and wet since the Last Glacial Maximum, while the climate in the Xinghua Bay has experienced a change from warm and humid, to moderate and dry, to warm and humid since the early-middle Holocene, which provides scientific theoretical support for the provenance and paleoenvironment of sediments in the study area and neighboring areas. [ABSTRACT FROM AUTHOR]

Motivation: The intrinsic characteristics of islands make them a unique study system for the investigation of ecological and evolutionary dynamics. The Mediterranean Basin, an island‐rich biodiversity hotspot, still lacks a comprehensive spatial database for these geographic features. This study presents the first comprehensive spatial database of all Mediterranean islands larger than 0.01 km2, aiding ecological investigations and interdisciplinary research. Main types of variable contained: The MEDIS spatial database offers detailed information on 39 geographic, climatic, ecological and land‐use variables, including island area, perimeter, isolation metrics, climatic space, terrain data, land cover, palaeogeography, road networks and geological information, providing a multifaceted view of each island's characteristics. Spatial location and grain: The study encompasses 2217 islands in the Mediterranean Basin larger than 0.01 km2. The spatial grain of the datasets on which the selected variables are based varies from 10 m (ESA WorldCover) to 1 km (CHELSA‐BIOCLIM+). Time period and grain: The spatial database incorporates data from various sources, each with its own timeframe, such as the Global Shoreline Vector from 2014 Landsat imagery and the WorldCover dataset from 2021. Historical data like the Paleocoastlines GIS dataset offer insights into island configurations during the Last Glacial Maximum. Major taxa and level of measurement: While not focusing on specific taxa, the study lays the foundation for comprehensive research on Mediterranean islands, facilitating comparisons and investigations into the distribution of native, endemic or alien species. The level of measurement is extensive, encompassing a wide range of variables and providing polygonal features rather than centroids' coordinates. [ABSTRACT FROM AUTHOR]

Aim: How the ability of plants to move towards newly favourable habitats (dispersal limitation) impacts the change of biome distribution and transition under fast climate warming is still debated. Analysing vegetation change in the past may help to clarify the relative importance of underlying ecological processes such as climate, biotic interactions, and dispersal. In this study, we investigated how dispersal limitation affected the distribution of European forests in the last 18,000 years. Location: Southern and Central Europe. Taxon: Spermatophyta. Methods: Using the LPJ‐GM 2.0 model (an extension of LPJ‐GUESS), we simulated European vegetation from the end of the Last Glacial Maximum (18.5 ka) to the current time (0 ka). Using biome reconstructions from pollen data as reference, we compared the performance of two dispersal modes: with no migration constraints or seed limitation (free dispersal mode), and with plant establishment depending on seed dynamics and dispersal (dispersal limitation mode). Results: The model run, including migration processes, was better at capturing the post‐glacial expansion of European temperate forests (and the longer persistence of boreal forests) than the setting assuming free dispersal, especially during periods of rapid warming. This suggests that a number of (temperate) tree taxa experienced delayed occupancy of climatically suitable habitats due to a limited dispersal capacity, i.e., post‐glacial migration lags. Main Conclusions: Our results show that including migration processes in model simulations allows for more realistic reconstructions of forest patterns under rapid climate change, with consequences for future projections of carbon sequestration and climate reconstructions with vegetation feedback, assisted migration and forest conservation. [ABSTRACT FROM AUTHOR]

Aim: Ecological niche‐based models (ENM) frequently rely on bioclimatic variables (BioV) to reconstruct biogeographic scenarios for species evolution, ignoring mechanistic relations. We tested if climatic predictors relevant to species hydric and thermal physiology better proximate distribution patterns and support location of Pleistocene refugia derived from phylogeographic studies. Location: The Western Palaearctic. Taxon: Vipera berus and Zootoca vivipara, two cold‐adapted species. Methods: We used two sets of variables, that is physiologically meaningful climatic variables (PMV) and BioV, in a multi‐algorithm ENM approach, to compare their ability to predict current and Last Glacial Maximum (LGM) species ranges. We estimated current and LGM permafrost extent to address spatially the cold hardiness dissimilarity between both species. Results: PMV explained more accurately the current distribution of these two cold‐adapted species and identified the importance of summer temperature and solar radiation that constrain activity in cold habitats. PMV also provide a better insight than BioV predictors on LGM distribution. By including notably, the permafrost extent, PMV‐based models gave parsimonious putative arrangement and validity of refugia for each clade and subclade in accordance with phylogeographic data. Northern refugia were also identified from 48 to 52° N for V. berus and from 50 to 54° N for Z. vivipara. Main Conclusions: Our hybrid approach based on PMV generated more realistic predictions for both current (biogeographical validation) and past distributions (phylogeographic validation). By combining constraints during the activity period (summer climatic niche) and those inherent to the wintering period (freeze tolerance), we managed to identify glacial refuges in agreement with phylogeographic hypotheses concerning post‐glacial routes and colonization scenarios. [ABSTRACT FROM AUTHOR]