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I do not support modern ideas regarding the sheltering of northern species of amphibians and reptiles in southern refugia during glacial periods. The current article presents arguments that reject the traditional point of view. The northern species did not fall within southern refugia, and therefore new forms (haplotypes) appeared within the periglacial hyperzone. I describe how these processes may have taken place. [ABSTRACT FROM AUTHOR]

Aim: The Neotropics constitute the most biodiverse region of the world, yet its patterns of diversification and speciation differ among Neotropical areas and are not equally well understood. Particularly, avian evolutionary processes are understudied in the open habitats of temperate South America, where the role of glacial cycles is not clear. We analysed the evolutionary history of a Neotropical widespread bird species as a case study to evaluate its continental‐scale patterns and processes of diversification, with a focus on Patagonia. Location: Open habitats of the Neotropics. Taxon: Vanellus chilensis (Aves, Charadriiformes). Methods: We obtained reduced representation genomic and mitochondrial data from the four subspecies of V. chilensis to perform a phylogenetic/phylogeographical analysis and study the evolutionary history of the species. We complemented these analyses with the study of vocalizations, a reproductive signal in birds. Results: The initial diversification event within V. chilensis, approximately 600,000 years ago, split a Patagonian lineage from one containing individuals from the rest of the Neotropics. We found considerable gene flow between these two lineages and a contact zone in northern Patagonia, and showed that genomic admixture extends to northwestern Argentina. Shallower divergence was detected between the two non‐Patagonian subspecies, which are separated by the Amazon River. Vocalizations were significantly different between the two main lineages and were intermediate in their temporal and frequency characteristics in the contact zone. Main Conclusions: Patagonian populations of V. chilensis are clearly differentiated from those of the rest of the Neotropics, possibly as a consequence of Pleistocene glaciations. A secondary contact zone in northern Patagonia with extensive gene flow among lineages appears to be the consequence of post‐glacial, northward expansion of the Patagonian populations. Future analyses focused on the dynamics of the contact zone will allow us to establish whether the species continues to diverge or is homogenizing. [ABSTRACT FROM AUTHOR]

Upper Palaeozoic lacustrine basin deposits not only record local tectonism but are also an archive to evaluate global palaeoclimate changes linked to the Late Palaeozoic Gondwanan ice age. The Tournaisian Horton Group of Nova Scotia, south‐east Canada, accumulated in rift basins following the final accretion of peri‐Gondwanan terranes to the Appalachians. Sedimentology, mineralogy and geochemistry of the well‐exposed sandstones and shales at the classic Blue Beach section (ca 353.5 to 352 Ma) reveal the interplay of local tectonism and global climatic controls on lacustrine sedimentation. The lacustrine depositional environment gradually transitioned from deep water offshore at the base of the section to wave‐dominated and fluvial‐dominated nearshore at the top. Multiple small transgressive–regressive sedimentation cycles have an average 21 ka duration, likely related to Milankovitch cyclicity. Unusually abundant soft‐sediment deformation structures and landslides are the sedimentary responses to frequent earthquakes during the most active phase of rift subsidence. The overall succession shows changes from a shallowing‐up balanced‐filled to an overfilled lacustrine basin. The chemical weathering intensity index and the Th/K ratio show a longer‐term trend from dry and cool conditions low in the section to humid and warm conditions near the top, with rapid change in the transition period. The section records the peak of the global mid‐Tournaisian carbon isotope excursion and the corresponding cooling event (354 Ma to approximately 351 Ma). The sedimentary succession is a response to long‐term and short‐term climatic cycles influencing lake level and sediment supply during the time of maximum rift basin subsidence recorded by the soft‐sediment deformation structures. [ABSTRACT FROM AUTHOR]

Perturbations in stratospheric aerosol due to explosive volcanic eruptions are a primary contributor to natural climate variability. Observations of stratospheric aerosol are available for the past decades, and information from ice cores has been used to derive estimates of stratospheric sulfur injections and aerosol optical depth over the Holocene (approximately 10 000 BP to present) and into the last glacial period, extending back to 60 000 BP. Tephra records of past volcanism, compared to ice cores, are less complete but extend much further into the past. To support model studies of the potential impacts of explosive volcanism on climate variability across timescales, we present here an ensemble reconstruction of volcanic stratospheric sulfur injection (VSSI) over the last 140 000 years that is based primarily on terrestrial and marine tephra records. VSSI values are computed as a simple function of eruption magnitude based on VSSI estimates from ice cores and satellite observations for identified eruptions. To correct for the incompleteness of the tephra record, we include stochastically generated synthetic eruptions assuming a constant background eruption frequency from the ice core Holocene record. While the reconstruction often differs from ice core estimates for specific eruptions due to uncertainties in the data used and reconstruction method, it shows good agreement with an ice-core-based VSSI reconstruction in terms of millennial-scale cumulative VSSI variations over the Holocene. The PalVol reconstruction provides a new basis to test the contributions of forced vs. unforced natural variability to the spectrum of climate and the mechanisms leading to abrupt transitions in the palaeoclimate record with low- to high-complexity climate models. The PalVol volcanic forcing reconstruction is available at 10.26050/WDCC/PalVolv1 (Toohey and Schindlbeck-Belo, 2023). [ABSTRACT FROM AUTHOR]

We review the major phylogeographic patterns in Aotearoa New Zealand's terrestrial flora and fauna that have been associated with the Ōtira Glaciation of the Pleistocene, the end of which coincides with the global Last Glacial Maximum (LGM). We focus on (1) the complexity of biogeographic histories of New Zealand species, with LGM-driven phenomena overlaying the impacts of mountain-building and other drivers of phylogeographic structure; (2) the locations of glacial refugia and sets of taxa which may have shared refugia; and (3) the role of glaciation in driving diversification. We end with a brief focus on the next directions, including what can we learn about New Zealand's glacial history by expanding our phylogeographic toolbox to include genomic methods and hypothesis-driven inference methods. We provide follow-up questions which take advantage of the wealth of phylogeographic data for New Zealand. [ABSTRACT FROM AUTHOR]

Premise: Snow is an important environmental factor affecting plant distribution. Past changes in snowfall regimes may have controlled the demographies of snow‐dependent plants. However, our knowledge of changes in the distribution and demographies of such plants is limited because of the lack of fossil records. Methods: Population genetic and landscape genetic analyses were used to investigate the response of population dynamics of Arnica mallotopus (Asteraceae)—a plant confined to heavy‐snow areas of Japan—to changes in snowfall regimes from the Last Glacial Period to the Holocene. Results: The population genetic analysis suggested that the four geographic lineages diverged during the Last Glacial Period. The interaction between reduced snowfall and lower temperatures during this period likely triggered population isolation in separate refugia. Subpopulation differentiation in the northern group was lower than in the southern group. Our ecological niche model predicted that the current distribution was patchy in the southern region; that is, the populations were isolated by topologically flat and climatically unsuitable lowlands. The landscape genetic analysis suggested that areas with little snowfall acted as barriers to the Holocene expansion of species distribution and continued limiting gene flow between local populations. Conclusions: These findings indicate that postglacial population responses vary among regions and are controlled by environmental and geographic factors. Thus, changes in snowfall regime played a major role in shaping the distribution and genetic structure of the snow‐dependent plant. [ABSTRACT FROM AUTHOR]

The Ismenius Lacus region of Mars has a diverse geological history, and we present the first high‐resolution map of Deuteronilus Cavus (36.2°N; 14.0°E, ∼120 km diameter) in the fretted terrain south of the dichotomy boundary. Strong evidence suggests a volcanic origin of the regional plains, based on the ∼50 m thick volcanic bed underlying 180–300 m of sublimation residue associated with Amazonian plateau glaciation. Pervasive external volcanic flooding, internal erosional modification, and enlargement of a pre‐existing crater by up to 175%–200% resulted in the cavus' present shape. The phyllosilicates detected within Deuteronilus Cavus could be primary materials associated with the surficial aqueous activity, subsurface alteration products excavated by impacts, or a combination of both. We observe branching fluvial channels that are more recent than the traditional valley networks and may be related to fretted terrain resurfacing during the waning period of a high‐obliquity glaciation phase. This is consistent with our interpretation of the ∼600 m thick lobate and lineated deposits, which are remnants of receding glaciers. The glacial ice, protected by a 15–20 m insulating layer of debris cover, is of significant interest for future landing missions because of its potential to preserve biological and climatological signatures, to provide a critical test of Amazonian plateau glaciation, and to be used for in situ resource utilization. With our detailed geological mapping, we improved our understanding of the geological evolution and climatic conditions in the enigmatic fretted terrain near the dichotomy boundary. Plain Language Summary: The ∼120 km long Deuteronilus Cavus was initiated by an impact event. The resulting impact crater was modified by glacial erosional and fluvial processes, leading to the enlargement of 175%–200% of the pre‐existing crater. In addition, we find strong evidence for recent glaciation (<1 Ga) that left 180–300 m of sublimation residue on the plateau superimposed on a ∼50 m thick volcanic bed, suggesting a volcanic origin of the regional plains. During the waning period of a high‐glacial phase, the meltwater ponded on the surface of the cavus, altered surface rocks to produce phyllosilicates, formed channels (now observed as inverted sinuous ridges), and locally distributed branched fluvial channels that are more recent than the traditional valley networks. Glacial landforms still contain up to 600 m of remnant ice from the retreating glaciers at the end of the last glacial period. The relatively pure ice, protected by a 15–20 m insulating layer of debris cover, is critical for future landing missions because of its potential to preserve biological and climatological signatures and to be used for in situ resource utilization. Overall, this research enhances our understanding of the geological evolution and climatic history of Mars. Key Points: We have produced the first high‐resolution map of Deuteronilus Cavus in the fretted terrain south of the Martian dichotomy boundaryThe region records a complex erosional and depositional history, including fluvial and glacial processes in the Amazonian periodThis study provides a framework for exploration of high‐obliquity mid‐latitude plateau glaciation [ABSTRACT FROM AUTHOR]

Reconstructing the extent, style, timing and drivers of past mountain glaciation is crucial in both understanding past atmospheric circulation and predicting future climate change. Unlike in high‐elevation mountains situated in maritime and continental climates, less is known of past glaciation in mid‐altitude mountains, located in transitional climates, such as the Southern Carpathians of Romania. Despite these mountains harbouring a rich glacial geomorphology, this has never been systematically mapped according to well‐established morphological criteria, nor confidently related to former styles of glaciation. Therefore, filling this gap is important for not only accurately identifying glacial extents but also for establishing past glaciation styles and relating them to past ice dynamics and climate. Here, we devise the first glacial landsystem model for the Southern Carpathians, to enhance our understanding of the glaciation style and dynamics of past mountain glaciers in temperate‐continental climates. We present a geomorphological map, from which we infer the spatial and temporal evolution of glacial, periglacial and paraglacial landforms. We then assess the links between the mountain geomorphology and glaciation style and dynamics to construct a glacial landsystem model for debris‐charged plateau icefields and cirque glaciers in temperate‐continental mountain settings. [ABSTRACT FROM AUTHOR]

The analysis of LiDAR‐based digital elevation models revealed the existence of groups of longitudinal fractures in the ground in northern Poland at the limit of the ice sheet's extent during its last maximum. Our research on the closed elongated depressions (CEDs) of the Jedwabno test field (Szuć site, north‐east Poland) focuses on explaining their origins and their post‐glacial history. This region was covered by an ice sheet and glacitectonically active during the Vistulian, and at least some surface fractures are possible witnesses to this activity. Using geomorphological mapping, sedimentological and geophysical research, we assumed it was related that the origin of these features here is associated with groundwater migration at the end of the Vistulian glaciation or later when groundwater flow intensified due to a rapid climate warming that caused permafrost to melt. The thawing of permafrost caused to transition from continuous permafrost to discontinuous, which in turn created groundwater flow that was probably responsible for the development of the surface cracks (fractures). Radiocarbon, palaeobiological (pollen, Cladocera) and geochemical studies allowed for an estimation of the formation time of these unique surface cracks in the Older Dryas. Prevailing conditions were also reconstructed for the later dynamic changes of the end of the Late Vistulian glaciation and in the Late Holocene until the Subatlantic Period (Megalayan stage). The surface cracks with steep slopes, despite their small area, are extraordinary sedimentation traps that have, in a special way, retained an almost complete record of the environmental and climate changes of the Late Glacial. There are sedimentological gaps in the Holocene, especially after the Preboreal (old part of the Greenlandian Stage), caused by changes in water levels, aeolian processes and human activity. [ABSTRACT FROM AUTHOR]

The stability of contemporary ice shelves is under threat due to global warming, and the geological records in the Ross Sea offer such an opportunity to test the linkage between them. However, the absence of calcareous microfossils in the sediments of the Ross Sea results in uncertainties in establishing a precise chronology for studies. Hence, three sediment cores were collected and studied in terms of radiocarbon dating, magnetic susceptibility, and sediment grain size to reconstruct the environmental processes in the Ross Sea since the last glacial period. The main results are as follows: (1) two grain-size components were identified for the studied cores, which can be correlated to ice-shelf and sea-ice transport, respectively; (2) due to old-carbon contamination and an inconsistent carbon reservoir, the radiocarbon dates were generally underestimated, and as an alternative, changes in magnetic susceptibility of the studied cores can be tuned to the ice-core records to establish a reliable age–depth model and; (3) integrating sediment grain-size changes and comparisons with other paleoenvironmental proxies in the Antarctic, a process from a sub-ice sheet in the last glacial period to a sub-ice shelf in the glacial maximum, and, finally, to a glaciomarine state since the last deglacial period was identified in the western Ross Sea. Integrating these findings, the warming processes in the Antarctic were highlighted in the retreat processes of the Ross Ice Shelf in the past. [ABSTRACT FROM AUTHOR]

In 2019 a sinkhole (doline) occurred in Late Devensian till above fissured limestone in northern England. Most sediment plugging the fissure was evacuated down into a karstic drainage system. The residual sedimentary fill comprises three main lithofacies, dated using optically stimulated luminescence to between 170.7 ± 40.0 and 56.1 ± 13.5 ka. The earliest date demonstrates fissures were present in the limestone pavement at the time of Marine Isotope Stage (MIS) 6, or shortly thereafter. The fissure filled with fine sand and silt due to surface runoff and aeolian processes probably at the MIS 6 to MIS 5e transition after Wolstonian glacial ice had retreated. The deposits then collapsed into the karst system. Further fine sand and silt deposition occurred during MIS 3; this deposit filled the central cavity surrounded by residual MIS 6/5e deposits. The sequence was capped by till as Late Devensian (MIS 2) ice transgressed the area. Solution fissures in the karst surfaces of northern England may pre‐date the Late Devensian glaciation. Moreover, fissures are repositories of pre‐Devensian sediment deposits which survived the Late Devensian glaciation and the Ipswichian interglacial. Such sites should provide information on the nature and timing of pre‐Devensian glacial–interglacial events and shed light on basal ice conditions and glaciokarst drainage behaviour. [ABSTRACT FROM AUTHOR]

The debate over isostatic uplift versus discharge as drivers of Quaternary river incision is explored here through geospatial analysis of a ~250‐m‐relief terrace sequence from the Río Pinturas (Argentine Patagonia). The geomorphic setting of the Cañadon Caracoles reach allows evaluation of discharge as a driver of terrace incision because advancing ice during Pleistocene glaciations blocked Pacific drainage and routed meltwater from an expanded ~104‐km2 catchment to the Atlantic through the dryland steppe of the study area. Twenty‐two terrace levels, some assigned to previously dated ice margins [Marine Isotope Stage (MIS) 32–36, MIS 16, MIS 8 and MIS 2], were identified. Average net incision since 800 ka (~0.34 m ka−1) exceeded regional uplift rates. The MIS 2 terraces, with ante quem and post quem age constraint on the timing of terrace formation, show that terrace incision was episodic and faster still during a transitional warming climate. Glacier recession and proglacial lake formation at ~18 ka led to rapid incision of ~11.7 m ka−1 over a few millennia. River capture and negligible flow from ~15.0 ka caused fan‐dammed lake formation on the valley floor and vertical stability during MIS 1. The Pinturas terraces demonstrate rapid incision can be driven by discharge and sediment dynamics. [ABSTRACT FROM AUTHOR]

Recently, a record of large, mostly unknown volcanic eruptions occurring during the younger half of the last glacial period (12–60 ka) has been compiled from ice-core records. In both Greenland and Antarctica these eruptions led to significant deposition of sulfate aerosols, which were likely transported in the stratosphere, thereby inducing a climate response. Here we report the first attempt to identify the climatic impact of volcanic eruptions in the last glacial period from ice cores. Average negative anomalies in high-resolution Greenland and Antarctic oxygen isotope records suggest a multi-annual volcanic cooling. Due to internal climate variability, glaciological noise, and uncertainties in the eruption age, the high-frequency noise level often exceeds the cooling induced by individual eruptions. Thus, cooling estimates for individual eruptions cannot be determined reliably. The average isotopic anomaly at the time of deposition also remains uncertain, since the signal degrades over time as a result of layer thinning and diffusion, which act to lower the resolution of both the oxygen isotope and sulfur records. Regardless of these quantitative uncertainties, there is a clear relationship of the magnitude of isotopic anomaly and sulfur deposition. Further, the isotopic signal during the cold stadial periods is larger in Greenland and smaller in Antarctica than during the milder interstadial periods for eruptions of equal sulfur deposition magnitude. In contrast, the largest reductions in snow accumulation associated with the eruptions occur during the interstadial periods. This may be the result of a state-dependent climate sensitivity, but we cannot rule out the possibility that changes in the sensitivity of the isotope thermometer or in the radiative forcing of eruptions of a given sulfur ejection may play a role as well. [ABSTRACT FROM AUTHOR]

The Balkans are considered a major glacial refugium where flora and fauna survived glacial periods and repopulated the rest of Europe during interglacials. While it is also thought to have harboured Pleistocene human populations, evidence linking human activity, paleoenvironmental indicators and a secure temporal placement to glacial periods is scant. Here, we present the first intra-tooth multi-isotope analysis for the European straight-tusked elephant Palaeoloxodon antiquus, on an adult male individual excavated in association with lithic artefacts at the MIS 12 site Marathousa 1 (Megalopolis basin, Greece). The studied find also exhibits anthropogenic modifications, providing direct evidence of hominin presence. We employed strontium, carbon and oxygen isotope analysis on enamel bioapatite to investigate its foraging and mobility behaviour, using a sequential sampling strategy along the tooth growth axis of the third upper molar, to assess ecological changes during the last decade of life. We found a geographically restricted range, in a C3-dominated open woodland environment, and relatively stable conditions over the examined timeframe. Our results show that, despite the severity of the MIS 12 glacial, the Megalopolis basin sustained a mesic habitat, sufficient plant cover and limited seasonal fluctuations in resource availability, pointing to its role as a glacial refugium for both fauna and hominins. [ABSTRACT FROM AUTHOR]

Ellobium chinense is an airbreathing, pulmonate gastropod species that inhabits saltmarshes in estuaries of the northwestern Pacific. Due to a rapid population decline and their unique ecological niche in estuarine ecosystems, this species has attracted special attention regarding their conservation and the genomic basis of adaptation to frequently changing environments. Here we report a draft genome assembly of E. chinense with a total size of 949.470 Mb and a scaffold N50 of 1.465 Mb. Comparative genomic analysis revealed that the GO terms enriched among four gastropod species are related to signal transduction involved in maintaining electrochemical gradients across the cell membrane. Population genomic analysis using the MSMC model for 14 re-sequenced individuals revealed a drastic decline in Korean and Japanese populations during the last glacial period, while the southern Chinese population retained a much larger effective population size (Ne). These contrasting demographic changes might be attributed to multiple environmental factors during the glacial–interglacial cycles. This study provides valuable genomic resources for understanding adaptation and historical demographic responses to climate change. [ABSTRACT FROM AUTHOR]

The aim of the study is the reconstruction of paleoclimatic patterns in the formation of the Chumbur-Kosa (MIS-17.MIS-1) loess–soil sequences and the assessment of the possibility of using phytolithic analysis to reconstruct the vegetation cover in the interglacial and glacial periods of the Pleistocene. Mean annual precipitation was calculated using the magnetic susceptibility. It has been established that in the Pleistocene there was a directed climate change towards aridization, in which the amount of precipitation during the interglacial periods decreased from 600 to 550 mm/year, and during the glacial periods it did not exceed 200–250 mm/year. Aridization of the climate led to xerophytization of plant communities, a decrease in bioproductivity and landscape diversity. In the warm periods of the Pleistocene, meadow–forb associations prevailed, which were replaced by steppe associations at the onset of the glacial stage. Natural and climatic zones were within the modern boundaries, demonstrating the relative stability of the steppe landscapes to global climatic fluctuations. [ABSTRACT FROM AUTHOR]

This article investigates the morphostructural evolution of the Labe and Jizera rivers confluence area in the Bohemian Massif of Czechia. The main stages of morphostructural evolution are identified and related landform patterns are described. The lithological and tectonic character of this contact area between the Barrandian and the Bohemian Cretaceous Basin has been gradually evolving since the Early Palaeozoic. Tectonic subsidence of the northeastern part of the Bohemian Massif and the Cretaceous transgression of the sea caused extensive marine sedimentation, which covered the pre-Cenomanian relief. The uplift of the Bohemian Massif during the Santonian initiated a widespread erosion and denudation in the Tertiary. The Labe River valley constitutes a remarkable boundary between the morphostructural plateaus in the south and the system of river accumulation terraces of the Labe and Jizera in the north. The originally extensive and currently considerably eroded III. river terrace of the Labe was formed in the Elsterian glacial period (Cromerian complex c). The conspicuous Jizera alluvial fan developed during the aggradation phase of the VII. river terrace in the Upper Pleistocene. Subsidence along the NW-SE-trending Labe Fault zone, deciphered from the vertical throw of the VII. terrace rock bases of Labe as well as related paleochannels of its local tributaries, which caused the current asymmetry of the Labe valley, reached up to 14 meters prior to the Holocene. The different rock resistance to weathering, arrangement of fault structures and neotectonic movements that took place even during the late Quaternary significantly influenced the intensity of varied climate-morphogenetic processes. [ABSTRACT FROM AUTHOR]

The Suwałki Glacial Megaflood Landsystem documented in NE Poland led to further morphological analysis of bedforms that originated from glacial lake-outburst floods (GLOFs) in the central and eastern parts of the Augustów Plain. This article focuses on (1) the recognition of largescale subaqueous dunes in the vicinity of Serwy Lake, (2) the creation of a database consisting of relevant morphometric parameters (lengths, heights and gradients of stoss and lee slopes) and indexes (steepness and asymmetry ratios) and (3) comparison with other landforms that undoubtably indicate glacial floods (e.g., Missoula, Altai, British Columbia, Wigry Lake). The remote identification and measurement of the megadunes' morphometry based on LiDAR data and digital elevation model with resolution 1×1 m (using hillshade and geomorphons) yielded data characterising 254 bedforms. These represent two-dimensional large-scale subaqueous dunes, which have lengths varying between 23.6 and 241.8 m and average heights of 0.6-5.4 m. Moreover, their morphometric variation creates a continuum typical of subaqueous dunes and has similarities to prominent examples linked to GLOFs. The study is especially crucial due to the lack of a wide range of information about megadune development under unconfined settings during the Weichselian glaciation. [ABSTRACT FROM AUTHOR]

Fruit flies (Tephritidae: Dacini) are a frugivorous insect group that exhibit high endemic diversity in the rainforests of Australia and the western Pacific. In this region, biogeography has been influenced by tectonic plate movements and cycles of isolation and re‐connection of landmasses and rainforest habitats during glacial periods. However, how such factors have influenced the speciation and historical dispersal of the regional Dacini is largely unknown. To address this, we use a dated phylogeny to reconstruct the biogeographical history of the tribe. We found the Dacini radiated eastward into the Pacific islands largely from sources in New Guinea. We also found evidence for historical dispersal from both Australia and New Guinea into New Caledonia, a pathway unique to this island compared with neighbouring islands. There was also evidence for multiple, bidirectional dispersal events between Papua New Guinea and Australia, likely facilitated by the cyclically exposed Torres Strait land bridge. Cape York in far northern Australia was likely the only entry point for species dispersing into Australia; there was no evidence for entry of flies into Australia directly from West Papua or Wallacea. Several lineages radiated after entering Australia, such as members of the Bactrocera dorsalis species group. Within Australia, speciation was not associated with the biogeographic barriers known to have impacted other rainforest fauna in eastern Australia. Overall, we demonstrate that isolation between islands and large landmasses is important in the evolution of the Australo‐Pacific Dacini, but the reason for their extensive radiation within Australia and Papua New Guinea remains unclear. [ABSTRACT FROM AUTHOR]

Simple Summary: One of the main differences between the modern fauna of steppe and desert-steppe insects and the similar fauna of the Last Ice Age is the current leading position of darkling beetles (Coleoptera, Tenebrionidae), which are represented in fossil faunas only by singletons. We hypothesize that the reason lies in the insufficient cold resistance of these insects for successful overwintering. We studied the cold resistance of adults from five species of darkling beetles from the Altai Mountains that overwinter in the soil and the larvae from one such species. The ranges of three of these are limited from the north by the desert-steppe margin of Central Asia with extremely low air temperatures. More than 50% of individuals of these species in the experiment did not withstand cooling below −22 °C. Temperatures in the soil of natural habitats at a depth of 10 cm are close to or lower than the above values. Overwintering is therefore possible in places with greater snow thickness (hollows, wind shade of shrubs and large cereals). Since darkling beetles are now on the border of temperature resistance in the Altai, they likely did not exist in the much more severe conditions of the glacial periods in the Altai Mountains, West Siberian Plain, and Northeast Asia. The level of diversity and abundance of darkling beetles (Coleoptera, Tenebrionidae) is the main difference between the late Pleistocene and modern insect faunas of arid regions. In the Pleistocene assemblages they are extremely rare, whereas in the modern ones they predominate. It is assumed that the reason for their rarity in fossil entomological complexes is their lack of cold resistance. The supercooling points (SCP) and low lethal temperatures (LLT) of adults from five species of Altai darkling beetles that overwinter in the soil and larvae from one such species were measured in the laboratory. All beetles supercooled at negative temperatures but could not survive freezing, with the average SCP of the most cold-resistant species between −25.7 and −21.7 °C (Bioramix picipes, Anatolica dashidorzsi, and Penthicus altaicus). However, 50% of the individuals from different species in the experiment died after exposure during two days at temperatures ranging from −22 to −20 °C. The focal species are distributed in parts of Central Asia with an extreme continental climate, and the temperatures measured in the soil of these natural areas turned out to be lower than or close to the limit of cold resistance of the beetles. Overwintering of darkling beetles is therefore only possible in areas with deep snow: in hollows, under bushes, and under large cereals. Darkling beetles with poor cold resistance could not have existed in the colder climate of the late Pleistocene, which explains their absence from fossil fauna. [ABSTRACT FROM AUTHOR]

Martian outflow channels and valley networks raise six questions and the first four are addressed in this part: 1) how were outflow channels and valley networks carved, likely from water?; 2) Were the channels and valley networks eroded by a few catastrophic floods or many small flows?; 3) What is the origin of the water: groundwater, rainfall and runoff, or both? If groundwater, how was it recharged?; and 4) What is the quantity of water needed for erosion; estimates varying from 3 m to 5000 m GEL. Ultimately, did water come from impacts, volcanism, or both? [ABSTRACT FROM AUTHOR]

Identifying the drivers of microgeographic speciation (i.e. speciation over small, local geographic scales) is key to understand the origin of speciose groups. Here, we use genomic data to infer the demographic processes underlying diversification in Poecilimon luschani (Orthoptera: Tettigoniidae), a species complex belonging to the most diverse genus of bush crickets from the Mediterranean region (>170 taxa) that comprises three recognized subspecies with small allopatric distributions in the topographically complex Teke Peninsula, southwestern Anatolia. Phylogenomic reconstructions that include all other taxa within the species group confirmed that subspecies of P. luschani originated from a common ancestor during the Pleistocene, supporting recent (<1 Ma) diversification within a small geographical area (ca. 120 × 80 km). Genetic clustering analyses corroborated the distinctiveness of each subspecies and the cohesiveness of their respective populations, with abrupt genetic discontinuities coinciding with contemporary range boundaries. Indeed, our analyses uncovered the presence of two sympatric cryptic sister lineages that diverged <300 ka ago and do not admix despite being co-distributed. Collectively, these results support that all lineages within the complex represent independently evolving entities corresponding to full-fledged species. Statistical evaluation of alternative models of speciation strongly supports a scenario of divergence in isolation followed by a period of limited gene flow during the last glacial period, when all lineages experienced marked expansions according to demographic reconstructions. Our study exemplifies how localized allopatric divergence and fast evolution of reproductive isolation can promote microgeographic speciation and explain the high rates of endemism characterizing biodiversity hotspots. [ABSTRACT FROM AUTHOR]

China has the most numerous Danxia and Karst landscapes, which serve as special terrestrial islands harboring ample endemic species, though how did these endemic species spread among those isolated sites is still an unresolved issue. To address this question, we explored the phylogeographical structure and demographic history of Firmiana danxiaensis, a tree species endemic to Danxia and Karst landscapes. We collected 295 samples (28 populations) of F. danxiaensis. Plastid genomes were assembled for 25 representative samples. Sanger sequencing of four plastid regions and restriction‐site‐associated DNA sequencing were performed on the 28 populations. The phylogenetic tree constructed from plastid genomes and restriction site‐associated DNA sequencing (RAD‐seq) data supported that F. danxiaensis originated from Mount Danxia and Nanxiong Basin, spread to Karst landscapes near Yingde City, and then back to Danxia Mountain and the Nanxiong Basin. In the Nanxiong Basin, the latter arrivals captured the plastid of the former. Population analyses revealed strong population structure among and within Danxia and Karst landscapes, possibly due to low seed and pollen dispersal abilities of the species. The demographic and ecological niche modeling approaches suggested that F. danxiaensis have widely occurred in the southeast of China during the last glacial period, and later retreated to the cliffs of Danxia and Karst landscapes due to temperature rising and competition failure. The declining of the effective population size of the species throughout the postglacial period suggested that global warming, agriculture, and industrial civilizations could have affected the survival of this species, and more measures should be taken to conserve these species. [ABSTRACT FROM AUTHOR]

Basal gravel and sand mantling the bedrock floors of buried valleys throughout the Canadian Interior Plains, and conformably overlying proglacial lacustrine sediment, comprise the Empress Group. While previously conceptualized as stratigraphically equivalent deposits of preglacial rivers prior to the first and most extensive continental and montane glaciations, subsequent stratigraphic studies indicated that buried valley basal gravel must have been deposited between, or during, progressively more extensive continental glaciations and could not be stratigraphically equivalent throughout the buried valley network. However, in the general absence of formation-rank stratigraphic description of basal gravel units that might better inform the geologic history of the deposits, most workers simply consider Empress Group sediments time-transgressive. In this paper, we examine basal gravel at provincial and regional scales to understand its genesis and geologic history. At the provincial scale, we map basal gravel in three dimensions using a novel machine learning approach. At the regional scale, we formally define basal gravel formations at either end of the largest buried valley system in Alberta, which informs its glacial history and physiographic development and shows the importance of formation-rank stratigraphic description. Our results indicate that the buried valley network across Alberta is palimpsest in genesis and basal gravel units within it are chronostratigraphically intercalated between tills. We advocate that the Empress Group definition be extended across Alberta with modifications to improve its clarity and utility, and formally define the Old Fort, Unchaga, Ipiatik, and Winefred formations as part of the Empress Group. [ABSTRACT FROM AUTHOR]

Objective: We propose that deepwater Cisco Coregonus artedi (sensu lato) survived Wisconsin ice advances through introgression with shallow‐water Cisco ~65 ka followed by expression of introgressed genomic fragments after the last retreat of ice from the Great Lakes ~15 ka. Methods: We reviewed Wisconsin Glaciation in relation to putative introgression within Cisco and employed a phylogeographic approach to substantiate locations of Cisco refugia and the implications for dispersal of Cisco ahead of the last advance of Wisconsin ice. Result: We showed that deepwater Cisco, in contrast to shallow‐water Cisco, were very unlikely to have survived glacial advances and that a massive introgression event between both types likely occurred as the first of two Wisconsin ice advances reached the Great Lakes ~65 ka. Conclusion: The most‐parsimonious explanation for the distribution of deepwater Cisco involves long‐ago introgression as a precursor to its divergence from shallow‐water Cisco following the final retreat of Wisconsin ice. Impact statementThis study will impact management of a group of fishes called ciscoes that once were prominent in every Great Lake. Ciscoes were depleted everywhere but in Lake Superior due to overfishing, pollution, and introduced species, but efforts are ongoing to restore them by stocking from areas where they persist. Picking the right donor populations is essential if restoration is to be successful, and this study expands the field of candidate donors by showing that hybridized populations are a normal feature of cisco biology. Hybridization, which is conventionally viewed as impairing fitness in most fish populations, was shown in this study to be an adaptation by ciscoes to their near extinction by advancing ice sheets during the Ice Age. [ABSTRACT FROM AUTHOR]

Polish forests differ in their potential to provide ecosystem services (ES), but it is unclear how and to what extent. We assessed the potential of 35 forest habitat types to provide 17 key ES and showed that the montane mesic broadleaved forest has a high potential to provide the largest number of key forest services (14 out of 17), which gives it the status of a multi-service hotspot. The highest overall potential was found in the forests of mountain regions, slightly lower in the postglacial northern regions, and the lowest in the central lowland regions. [ABSTRACT FROM AUTHOR]

The lake depressions in the Mongolian Altai Mountains, and the issues related to their formation have yet to be thoroughly examined in previous research. Previous studies primarily focused on the paleogeographical evolution and glaciation dynamics of the Altai Mountains. This study presents relationships between tectonic and glacial processes that have formed the lake depressions, such as Khoton, Khurgan, Dayan, Khar (western), and Khar (eastern) in the Mongolian Altai Mountains. The depressions of Khoton, Khurgan, and Dayan lakes are situated along regional fault zones, extending in an nortwest-southeast direction, forming intermontane depressions directly connected to the Mongolian Altai Mountains. However, the depressions of Dayan, Khar (western), and Khar (eastern) lakes have been dammed by moraine deposits in the near portion of the depression. The compliance matrix of tectonic geomorphological criteria indicates that the Khoton, Khurgan, Dayan Lake, and Khar (western) Lake depressions are more than 50% compatible. Similarly, the compliance matrix for glacial geomorphological criteria indicates more than 60% compliance for all lake depressions. The Mongolian Altai intermontane depressions are thus of tectonic origin, whereas the lakes have a glacial origin, resulting from dammed moraine sediments. The significance of this work lies in demonstrating how geomorphological research can be employed to provide a detailed understanding of the pattern of lake depressions. [ABSTRACT FROM AUTHOR]

We investigated benthic foraminifera in cores GPC03 and GPC04 in the northeast tropical Indian Ocean (TIO) over the past ∼450 ka to evaluate the ballasting effect of particulate organic matter (POM) and the long‐term zonal change during the mid‐Brunhes dissolution interval (MBDI). Today, interannual climate and oceanographic variability in the TIO is governed by the Indian Ocean Dipole (IOD), which manifests as asymmetric zonal oceanographic change. Previous studies have been conducted to uncover such zonal paleoceanographic change and have referred to their climatic pattern as an "IOD‐like mode." In the northeast TIO, after ∼390 ka, contributions of lithogenic matter and %Nuttallides umbonifer were unusually high under the better carbonate preservation conditions during glacial periods. Our findings suggest that the effect of lithogenic matter from the Ganga‐Brahmaputra‐Meghna River system increased significantly under glacial low sea‐level conditions, possibly by lateral transport along the continental slope. As a result, ballasting of POM seemed more efficient during glacial periods by abundant riverine lithogenic particles. In addition, the long‐term (∼320–200 ka) trend of high benthic foraminiferal accumulation rate (BFAR) and several short‐term fluctuations of high BFAR at ∼310, ∼280, ∼260, and ∼240 ka were discernible. We attribute these changes to increased paleoproductivity driven by upwelling, which may be related to the Indian Ocean equatorial westerlies and Indian summer monsoon dynamics via variations arising from precession. We propose that a long‐term mean‐state transition of IOD‐like mode might have occurred during the MBDI, similar to other hypotheses invoking concomitant changes in the El Niño‐Southern Oscillation system. Key Points: Nuttallides umbonifer were commonly observed in the glacial sediments at the Ninetyeast Ridge of the northeast tropical Indian OceanBallasting of particulate organic matter by the riverine lithogenic particles was more efficient during the glacial periods at the Ninetyeast RidgeWe found evidence for a long‐term mean‐state transition in northeast tropical Indian oceanography since the mid‐Brunhes period [ABSTRACT FROM AUTHOR]

Precambrian tropical glaciations pose a significant challenge to our understanding of Earth's climate. A popular explanation invokes runaway ice-albedo feedback leading to "iceball earth", an extreme state conflicting however with the sedimentary evidence of an open ocean and active hydrological cycle. We point out flawed physics of the runaway scenario, which overlooks potency of the ocean heat transport in deterring the perennial sea ice. Nor is frozen ocean needed for tropical glaciation as the latter requires only that the tropical land be cooled to below the marking temperature of the glacial margin, which is necessarily above the freezing point to counter the yearly accumulation. Since tropical glaciations generally coincide with Precambrian supercontinents, we posit that it is their blockage of the brighter tropical sun that causes the required cooling. To test this hypothesis, we formulate a minimal two-box model, which is nonetheless thermodynamically closed and yields lowering tropical/polar temperatures with increasing tropical land, whose crossings of the glacial marking temperature would divide non/polar/pan-glacial regimes--the last being characterized by tropical glaciation abutting an open ocean. Given the observed chronology of paleogeography, our theory may provide a unified account of the faint-young-sun paradox, Precambrian tropical glaciations and glacio-epochs through Earth's history. [ABSTRACT FROM AUTHOR]

The results of 230Th/U dating of massive sulfides and metalliferous sediments (288 and 245 analyses, respectively) of hydrothermal sites in the northern equatorial area of the Mid-Atlantic Ridge (MAR) from 12° to 20° N are presented. The maximum and average ages of sulfides are 223 ± 38.2 and 80.5 ka, respectively. The comparison of ages of massive sulfides from various MAR hydrothermal sites showed asynchronous stages of hydrothermal activity along the ridge axis indicating the features of tectonic activity and magmatism, which control the hydrothermal activity within each region. The glaciation periods, which record the activation and low- and high-temperature hydrothermal activity, are an exception. A direct positive correlation between the age of a hydrothermal site and its distance from the axial ridge zone is typical of mafic-related hydrothermal sites in contrast to ultramafic-related hydrothermal sites, which is related to the different scenarios of the formation of these two types of sulfide mineralization within slow-spreading ridges. The ages of sulfides and sediments have been jointly analyzed based on the example of the Pobeda and Semenov hydrothermal sites. The interpretation of data on sediments indicates the continuous character of hydrothermal activity, which is partly supported by the age of sulfides. [ABSTRACT FROM AUTHOR]

This study aimed to investigate the genetic diversity and relationships among Apodemus mystacinus lineages by analyzing mitochondrial Cytochrome b sequences. The study included samples from Iranand south east Turkey (Hakkari and Şırnak), in addition to previously studied populations. The results showed differences in the relationships among lineages and the structure of the phylogenetic tree compared to previous studies. A. m. mystacinus lineage, represented by samples from southwest Anatolia and Crete, was located at the base of the tree. The Iranian specimens were clustered with the southeastern specimens of Turkey in a separate lineage, indicating a possible refugium for A. mystacinus populations during glacial periods. The study also suggested that the expansion of A. mystacinus into Anatolia and neighboring regions during the Pleistocene facilitated its colonization of the Aegean islands. The differentiation between A. m. euxinus lineage and the south east Anatolia-Iran lineage may have resulted from the ancestral population in eastern Turkey diverging into two different lineages with one expanding its range towards the Black Sea and the other migrating towards the Zagros Mountains in Iran. These findings contribute to the understanding of the evolutionary history and phylogeography of A. mystacinus in its main range. [ABSTRACT FROM AUTHOR]

Global climatic changes in recent decades cause changes in the dynamics of mountain geosystems. Of interest is the response of nival-glacial inland geosystems, which is different from those in the pre-Oceanic regions. In 2013, the authors substantiated the expediency of separating the nival-glacial mountain range geosystems within the Baikal Rift Zone and Mongolian Altai into a meridional research transect, within which it is possible to establish latitudinal patterns of modern intracontinental glacier functioning. Over the past decade of ongoing studies of glacial forms within the transect, many new data have been collected and analyzed. The present article based on systematic generalizations of these materials. The analysis of the state of mountain glaciation in the south of Eastern Siberia and Mongolia in the last decades has revealed a number of peculiarities. The deglaciation that began in the 1970s–1980s continues in all the mountain systems under consideration. It is a reaction to global climatic changes. The greatest reduction is experienced by the near-slope glaciers and flattop glaciers and to a lesser extent by the cirque ice glaciers. They have a significant volume loss due to thinning, while changes in the area of such glaciers are less significant. This is the main difference between the intracontinental glaciers and the preoceanic glaciers. In general, many nival-glacial geosystems of transitional forms are formed. Quantitative characteristics are based on the calculation of the volume of the East Sayan glaciers measured by geophysical radar. Thus, over 120 years, the Peretolchina (northern) Glacier has decreased in length by a factor of 1.75, in area by a factor of 2.9, and in volume by a factor of 3.71. During the same period, the area of the neighboring Radde Glacier decreased from 0.43 to 0.09 km2; its thickness by 30 m; and, accordingly, its volume by 3 times. The warming of air temperature for Western Mongolia is 0.03–0.29°C/10 years and, for the Baikal region, 0.2–0.5°C/10 years. Warming of air temperatures in the ridges of the Mongolian Altai is noted up to 48° N, and southward the trend is unstable. [ABSTRACT FROM AUTHOR]

Models (paradigms) and former interpretations have often been presupposed when conducting field research. In the 19th century diamictites were for the first time interpreted to have originated from ancient glaciations. These interpretations have to a large part prevailed in the geological community, although there has been much progress in the areas of sedimentology, glaciology and physical geography. The present work is an effort to find criteria which most clearly discriminate between geological features produced by different processes, mainly glaciation and mass flow, the latter predominantly sediment gravity flows. Geological features which have been interpreted to have formed by glaciation throughout pre-Pleistocene Earth history are compared to similar-appearing geological features formed by mass flow and tectonics, so as to uncover variations in the appearance between features resulting from these different processes. The starting point for this comparison is documentation of the appearance of Quaternary products of erosion and deposition, in order to discern the origin of older formations. It is shown that the appearance and origin of pavements, dropstones, valleys, small-scale landforms, surface microtextures and most other geological features may in some cases be equivocal, but in others the details are indicative of the process which generated the feature. Detailed geological field data which have been compiled by geologists from outcrops of pre-Pleistocene strata, more often than is considered in most papers, commonly point to a mass flow origin, mainly a sediment gravity flow origin, rather than a glaciogenic origin. A process of multiple working hypotheses or interpretations is therefore advocated, based mainly on a comparison of the appearance of features formed by different geological processes documented from different research disciplines. Instead of starting with current interpretations or models, this multiple working hypothesis or methodology helps to avoid confirmation bias and jumping to conclusions. [ABSTRACT FROM AUTHOR]

Buried mounds have been identified on seismic reflection profiles in the southern Roosevelt sub-basin of the eastern Ross Sea, Antarctica. Since they have never been sampled, the composition of these mounds can only be inferred from their acoustic character. Previous studies have hypothesised that they are buried glacial moraines deposited by ice grounding near the paleo-continental shelf edge, suggesting the beginning of the growth of the West Antarctic Ice Sheet (WAIS) as early as the late Oligocene. This hypothesis conflicts with earlier evidence of the WAIS advance over the central-eastern Ross Sea. An alternative explanation for the origin of the mounds, as mud volcanoes, is formulated here on the basis of seismic reflection profile reprocessing and comparison with other, better studied, mound provinces in the Ross Sea. Shallow drilling is required to verify, which hypothesis is correct, and this has implications for various WAIS scenarios, ice volumes, and thermal rheological modelling. [ABSTRACT FROM AUTHOR]

The glacial–interglacial cycles of the Quaternary exhibit 41 kyr periodicity before the Mid-Pleistocene Transition (MPT) around 1.2–0.8 Myr ago and ∼ 100 kyr periodicity after that. From the viewpoint of dynamical systems, proposed mechanisms generating these periodicities are broadly divided into two types: (i) nonlinear forced responses of a mono- or multi-stable climate system to the astronomical forcing or (ii) synchronization of internal self-sustained oscillations to the astronomical forcing. In this study, we investigate the dynamics of glacial cycles simulated by the Earth system model of intermediate complexity CLIMBER-2 with a fully interactive carbon cycle, which reproduces the MPT under gradual changes in volcanic-CO 2 degassing and regolith cover. We report that, in this model, the dominant frequency of glacial cycles is set in line with the principle of synchronization. It is found that the model exhibits self-sustained oscillations in the absence of astronomical forcing. Before the MPT, glacial cycles synchronize to the 41 kyr obliquity cycles because the self-sustained oscillations have periodicity relatively close to 41 kyr. After the MPT the timescale of internal oscillations becomes too long to follow every 41 kyr obliquity cycle, and the oscillations synchronize to the 100 kyr eccentricity cycles that modulate the amplitude of climatic precession. The latter synchronization occurs with the help of the 41 kyr obliquity forcing, which enables some terminations and glaciations to occur robustly at their right timing. We term this phenomenon vibration-enhanced synchronization because of its similarity to the noise-enhanced synchronization known in nonlinear science. While we interpret the dominant periodicities of glacial cycles as the result of synchronization of internal self-sustained oscillations to the astronomical forcing, the Quaternary glacial cycles show facets of both synchronization and forced response. [ABSTRACT FROM AUTHOR]

During the Late Pleistocene, the Palaeo-Ems system (PES) was one of the major tributary channels feeding the Elbe Palaeovalley (EPV) and formed an important part of the drainage system of the continental northwestern Europe unglaciated hinterland. In this study, a detailed interpretation of high-resolution 2D sub-bottom profiler and Boomer grids were used to map the overall course of the submerged PES channel, as well as its spatial and stratigraphic relationships with other Quaternary geological units in the German North Sea. Mapping of buried tunnel valleys, a lacustrine-fill unit, straight channel structures was also carried out. The sedimentary record of the PES is represented by a low gradient and meandering channel which branched into two major pathways as it approached the EPV western flank. Its upstream to downstream trends, coupled with seaward decreasing gradient and sinuosity, are similar to those visible in present-day river deltas. Both the PES and EPV subsequently formed a combined depositional system, which was successively drowned due to the fast-rising relative sea level that overwhelmed the adaptation capabilities of the joint drainage system. For the first time, this study sheds light onto the PES/EPV morpho-stratigraphic relationships which played a key role in the coastal landscape architecture of the German North Sea since the Late Pleistocene. [ABSTRACT FROM AUTHOR]

Climatic and environmental conditions play a pivotal role in the evolution of the biosphere, serving as the primary natural factors influencing biological evolution and the development of human civilization. The study of the evolution of Earth's habitability primarily revolves around the reconstruction of climatic and oceanic conditions in geohistorical periods, shedding light on their dynamic changes. This paper collates classic geological indicators and geochemical proxies associated with paleo-climatic and oceanic environmental conditions. The latest "big data" analyses and simulations made possible by the availability of previously unimagined massive datasets reveal several key findings: During the early Paleozoic, atmospheric oxygen levels were low, and widespread oceanic anoxia was prevalent; the Devonian era witnessed a greenhouse climate, followed by the Carboniferous ice age characterized by higher oceanic oxidation levels and alkalinity. The latest Paleozoic deglaciation occurred under high pCO2 conditions, extending into much of the Mesozoic and early Cenozoic, marked by multiple hyperthermal and anoxia expansion events, until the resurgence of global glaciation in the middle-late stages of the Cenozoic, ultimately bringing environmental and climatic conditions closer to modern levels. By correlating the aforementioned long-term trends with major geological events, we can delineate the co-evolution of paleoclimate and oceanic environments in tandem with the development of Tethys tectonics as follows. (1) During the Proto-Tethys stage, global paleo-elevations were relatively low, and atmospheric oxygen levels were also relatively modest. Despite the occurrence of significant tectonic movements that led to noticeable transgressive-regressive cycles, their effects on climate and oceanic environments were somewhat limited due to the relatively weak interactions. (2) The emergence of the Paleo-Tethys was a significant event that coincided with the formation of the supercontinent Pangaea. Intensive orogenic movements during this period increased the global land area and elevation. This, in turn, led to enhanced terrestrial weathering, which elevated sea surface productivity and resulted in massive nutrient input into the oceans. Consequently, this process contributed to the rise of oxygen levels in the atmosphere and a decrease in atmospheric pCO2. These changes are considered potential driving mechanisms for late Paleozoic glaciation and oceanic oxygenation. (3) The transition from the Paleo-Tethys to the Neo-Tethys was closely linked to the breakup of Pangaea. During this period, the terrestrial weathering processes were relatively weak due to decreased continental elevations. This resulted in a long-term greenhouse climate and intermittent global oceanic events, which were responses to the high atmospheric pCO2 levels during the Mesozoic and early Cenozoic eras. (4) The Neo-Tethys stage ended with the dramatic uplift of the Alps-Himalaya Mountain ranges due to the collision of India and Asia. This uplift had a profound global impact, significantly increasing continental elevations. As a result, weathering and carbon burial processes intensified, leading to a reduction in atmospheric pCO2. Concurrently, this uplift played a crucial role in the establishment of the East Asian monsoon and North Atlantic deep-water circulations, both of which played a part in triggering the late Cenozoic ice age. These models suggest that the teleconnections between land and sea (orogeny-terrestrial weathering-marine carbon burial) span over the whole Phanerozoic and might have played a key role in balancing the Earth surface system. Combined, the tectonic, volcanic, paleo-climatic, as well as paleoenvironmental events recorded in the Tethys oceans and adjunct continents represent valuable natural experiments and lessons for understanding the present and the future of Earth's habitability. [ABSTRACT FROM AUTHOR]

Understanding changes in Earth's past can provide valuable insights into prediction of its future. An example is the interactions between the internal and external spheres of Earth. The cyclical northward breakup-drift of Gondwana, driven by the opening and closure of Proto-, Paleo-, and Neo-Tethyan oceans, facilitated the transfer of landmasses from the southern to the northern hemisphere, traversing the tropic region. We have observed a compelling correlation between episodic increases in landmass area within the tropic regions (those lying at less than 20° latitude) and a subsequent temperature decrease during the three major glacial periods in the last 500 million years. This phenomenon can be attributed to low latitude regions receiving more solar energy influx on Earth's surface than high latitude areas. In addition, an increase of landmass in tropic regions (low latitude) attenuates the net energy absorption by the Earth's surface, consequently impeding the conduction and convection of absorbed energy toward the poles. The result is a decrease in global surface temperature. The tropic regions, benefiting from abundant sunlight, create an ideal environment for the proliferation of marine plankton species. These species are important in the generation of organic-rich sediment. Massive biological debris is therefore deposited on continental margins when a continent drifts across the tropic region. This creates favorable conditions for future hydrocarbon and reservoir formation. Northward subduction of organic-rich sediments during the closure of the Tethyan oceans results in the generation of mafic arc magmas with low oxygen fugacity. This chemical environment helps the mineralization of reduced-type ore deposits such as tungsten, tin, and lithium. Subducted-driven plate tectonics in the Tethys realm changes the distribution of oceans and landmass, subsequently affecting the balance and distribution of solar energy across Earth's surface. These changes trigger consequential environmental shifts which in turn, impact the composition of rock and mineral along the Eurasian margin due to subduction. Consequently, the Tethyan realm and its history is an ideal natural laboratory for comprehending the processes and changes of the entire Earth's system. [ABSTRACT FROM AUTHOR]

The prevailing paradigm about the Quaternary ecological and evolutionary history of Central European ecosystems is that they were repeatedly impoverished by regional extinctions of most species during the glacial periods, followed by massive recolonizations from southern and eastern refugia during interglacial periods. Recent literature partially contradicts this view and provides evidence to re‐evaluate this Postglacial Recolonization Hypothesis and develop an alternative one. We examined the long‐term history of the flora of the Carpathian (Pannonian) Basin by synthesising recent advances in ecological, phylogeographical, palaeoecological and palaeoclimatological research, and analysing the cold tolerance of the native flora of a test area (Hungary, the central part of the Carpathian Basin). We found that (1) many species have likely occurred there continuously since before the Last Glacial Maximum (LGM); (2) most of the present‐day native flora (1404 species, about 80%) can occur in climates as cold as or colder than the LGM (mean annual temperature ≤+3.5°C); and (3) grasslands and forests can be species‐rich under an LGM‐like cold climate. These arguments support an alternative hypothesis, which we call the Flora Continuity Hypothesis. It states that long‐term continuity of much of the flora in the Carpathian Basin is more plausible than regional extinctions during the LGM followed by massive postglacial recolonizations. The long‐term continuity of the region's flora may have fundamental implications not only for understanding local biogeography and ecology (e.g. the temporal scale of processes), but also for conservation strategies focusing on protecting ancient species‐rich ecosystems and local gene pools. [ABSTRACT FROM AUTHOR]

Maqui (Aristotelia chilensis) is a small tree endemic to Patagonia. It is currently being actively domesticated for its edible berries, which have high polyphenol content and anti-oxidant capability. However, little is known about its population structure and evolutionary history, information which is useful for the design of effective conservation and domestication strategies. Based on information from other species, we hypothesize that genetic diversity in maqui is higher in northern population and decrease to the South, associated with past migration patterns and as a result has well-structured populations. To explore the genetic diversity of 14 populations (183 samples) of this species, that represent the geographic distribution of the species in Chile we used 13 polymorphic microsatellite markers. Clusters based on Bayesian genetic and spatial structure analyses were used to reconstruct patterns of phylogeographic and demographic history. We found that maqui populations are well-structured, with a substantial reduction of genetic diversity from north to south. The lowest diversity was found in areas that were once covered by ice during the quaternary glaciation. In conclusion, three main genetic groups were revealed by Structure analysis, and genetic diversity reduction from its northern limit in central Chile to the Patagonian region was found, suggesting that an active recolonization process took place during the last few millennia following the last glacial period. These results will help to define accessions from different regions and contribute to support conservation and domestication initiatives. [ABSTRACT FROM AUTHOR]

Reconstructions of the southwestern Laurentide Ice Sheet (LIS) from geomorphology have revealed complex cross‐cutting ice streams, indicative of surging and flow switching. This flow pattern and behaviour is distinct from the rest of the ice sheet where ice streams flowed radially to the ice sheet margin. Many ice streams in the southwestern sector originate around the Alberta Oil Sands (AOS). Previous reports have detected oil sands material in surficial and glacial sediments south of the AOS, demonstrating potential glacial mobilisation of the oil sands. In this study, we use geochemical fingerprinting to systematically investigate surficial sediments from the former Central Alberta Ice Stream (CAIS) flow track. We compare the geochemical signatures of 82 sediments from within and outside the CAIS limits with those of the AOS (from mines and natural exposures), using gas chromatography–mass spectrometry oil–oil correlation techniques. Our results provide geochemical evidence of glacial erosion and long‐distance mobilisation of AOS producing contamination signatures in sediments throughout the CAIS flow track. The strength of the AOS signature is particularly strong in sediments along the terminating margins, to the east of Calgary and in the Cooking Lake area to the southeast of Edmonton. These results inform theoretical models of enhanced slipperiness, inspired by slippery liquid infused porous surfaces (SLIPS), whereby oil lubrication of the basal sediment influences the degree of sliding and basal deformation in the ice stream. We hypothesise that naturally occurring hydrocarbons at the basal interface exerted control on the location of the onset zone of the CAIS and surrounding ice streams in Alberta. The enhanced slipperiness caused by oil contamination may also explain ice streaming and surging in other ice sheets, such as the Barents Sea Ice Sheet, where hydrocarbons are known to have been driven to the sedimentary interface during glaciation. [ABSTRACT FROM AUTHOR]

We introduce a new hypothesis concerning the role of internal climate dynamics in the non‐linear transitions from interglacial to glacial (IG‐G) state since the Mid Pleistocene Transition (MPT). These transitions encompass large and abrupt changes in atmospheric CO2, ice volume, and temperature that we suggest involve critical interactions between insolation and high amplitude oscillations in ocean/atmosphere circulation patterns. Specifically, we highlight the large amplitude of millennial‐scale climate oscillations across the transition from Marine Isotope Stage (MIS) 5 to 4, which we argue led to amplified cooling of the deep ocean and we demonstrate that analogous episodes of extreme cooling systematically preceded glacial periods of the last 800 kyr. We suggest that such cooling necessitates a reconfiguration of the deep ocean to avoid a density paradox between northern and southern‐sourced deep waters (SSW), which could be accomplished by increasing the relative volume and or salinity of SSW, thus providing the necessary storage capacity for the subsequent (delayed) and relatively abrupt drawdown of CO2. We therefore explain the transient decoupling of Antarctic temperature from CO2 across MIS 5/4 as a direct consequence of millennial activity at that time. We further show that similar climatic decoupling typically occurred during times of low obliquity and was a ubiquitous feature of IG‐G transitions over the past 800 kyr, producing the appearance of bimodality in records of CO2, benthic δ18O and others. Finally we argue that the apparent lack of bimodality in the pre‐MPT record of benthic δ18O implies that the dynamics associated with IG‐G transitions changed across the MPT. Key Points: Extreme interstadial‐like millennial‐scale Antarctic cooling systematically preceded transitions to a glacial state throughout the past 800 kyrSuch cooling could promote glacial ocean stratification by volume expansion and or salinification of southern‐sourced deep watersThese dynamics can explain the abrupt nature of interglacial‐glacial changes in for example, CO2 since the Mid Pleistocene Transition but apparently not before [ABSTRACT FROM AUTHOR]

There are few documentations of far‐field effects of coolhouse glaciation and its signature preserved within Middle Jurassic carbonate platforms. Through outcrop logging and time series analysis we document the cyclostratigraphy of the upper Bajocian‐Bathonian interval of the Adriatic Platform, Croatia. The 200 m thick, ∼3.3 Myr duration cyclic platform record consists of peritidal carbonate parasequences (n = 109) with high‐energy grainstone‐rudstone bases fining up into micritic carbonate caps. There is little evidence of long‐term exposure near purported sequence boundaries, indicating the succession is conformable above the parasequence scale. Time series were constructed using Dunham rank and stratigraphic position, and parasequence thickness and stratigraphic position. A statistical estimation of accumulation rates using average spectral misfit (ASM) and correlation coefficient (COCO) methods that compare spectral peaks with an astronomical model at various sedimentation rates suggests that these rates ranged from 4.5 to 6 cm/kyr, which is compatible with long‐term rates based on thickness divided by duration. The time series analysis of rank series and cycle thickness series indicates long‐term obliquity modulation (∼1 Myr), short obliquity modulation (173 kyr), strong obliquity, and weak precession. The 173 kyr cycle is particularly evident in the cycle thickness series. The similarity of the spectra to the obliquity‐dominated Cenozoic coolhouse supports moderate southern hemisphere glaciation driving glacioeustatic sea level changes during the Middle Jurassic. Plain Language Summary: Earth's climate has been paced by eccentricity of its orbit (periods of 405,000 and 100,000 years) which modulates precession (or wobble, ∼20,000 years), and the tilt (obliquity) of its axis (∼40,000 years), with tilt and wobble being slightly shorter as we go back in time. We examined the succession of carbonate rocks in a 166–169.5 million‐year‐old, Middle Jurassic carbonate platform in Croatia, deposited during a time when there is evidence of moderate glaciation at the poles. The results indicate that the rock record was dominated by the tilt signal with little evidence of eccentricity. This is very similar to the deep sea record from 2 million to 700,000 years ago, which also is dominated by obliquity associated with moderate glaciation at both poles. The results strongly support the contention of moderate glaciation during the Middle Jurassic. Key Points: Middle Jurassic Bajocian‐Bathonian dominated by obliquity forcing of climate/sea levelOrbital signal is dominated by ∼1 Myr long obliquity cycle, short (173 kyr) obliquity modulation cycle, obliquity, and minor precessionObliquity forcing supports the existence of moderate ice sheets at high latitudes in the Middle Jurassic [ABSTRACT FROM AUTHOR]

Terrestrial‐marine dust fluxes, pedogenic carbonate δ13C values, and various paleovegetation proxies suggest that Africa experienced gradual cooling and drying across the Pliocene‐Pleistocene (Plio‐Pleistocene) boundary (2.58 million years ago [Ma]). However, the timing, magnitude, resolution, and relative influences of orbitally‐driven changes in high latitude glaciations and low latitude insolation differ by region and proxy. To disentangle these forcings and investigate equatorial eastern African climate across the Plio‐Pleistocene boundary, we generated a high‐resolution (∼3,000‐year) data set of compound‐specific n‐alkane leaf wax δ2H values—a robust proxy for atmospheric circulation and precipitation amount—from the HSPDP‐BTB13‐1A core, which spans a ∼3.3–2.6 Ma sequence in the Baringo‐Tugen Hills‐Barsemoi Basin of central Kenya. In combination with the physical sedimentology, our data indicate that precipitation varied strongly with orbital obliquity, not precession, during the late Pliocene, perhaps imparted by variations in the cross‐equatorial insolation gradient. We also observe a marked shift toward wetter conditions beginning ∼3 Ma that corresponds with global cooling, drying in western Australia, and a steepening of the west‐east zonal Indian Ocean (IO) sea surface temperature (SST) gradient. We propose that northward migration of the Subtropical Front reduced Agulhas current leakage, warming the western IO and causing changes in the IO zonal SST gradient at 3 Ma, a process that has been observed in the latest Pleistocene‐Holocene but not over longer timescales. Thus, the late Cenozoic moisture history of eastern Africa is driven by a complex mixture of low‐latitude insolation, the IO SST gradient, and teleconnections to distal high‐latitude cooling. Key Points: We present new high resolution (3,000‐year) leaf wax δ2H data from central Kenya spanning 3.3–2.6 million years before present (Ma)Pronounced 41,000‐year variability throughout is potentially attributable to the cross‐equatorial insolation gradientLong‐term (>200,000‐year) variability in eastern African hydroclimate tracks the zonal Indian Ocean surface temperature gradient [ABSTRACT FROM AUTHOR]

We explore the spatial and temporal variations in denudation rates in the northern Pamir—Tian Shan region using 10Be‐derived denudation rates from modern (n = 110) and buried sediment (2.0–2.7 Ma; n = 3), and long‐term exhumation rates from published apatite fission track (AFT; n = 705) and apatite (U‐Th‐Sm)/He (AHe; n = 211) thermochronology. We found moderate correlations between denudation rates and topographic metrics and weak correlations between denudation rates and annual rainfall, highlighting complex linkages among tectonics, climate, and surface processes that vary locally. The 10Be data show a spatial trend of decreasing modern denudation rates from west to east, suggesting that deformation and precipitation control denudation in the northern Pamir and western Tian Shan. Farther east, the denudational response of the landscape to Quaternary glaciations is more pronounced and reflected in our data. Modern 10Be denudation rates are generally higher than the long‐term AFT and AHe exhumation rates across the studied area. In the Kyrgyz Tian Shan, on average, the highest 10Be denudation rates are recorded in the Terskey range, south of Lake Issyk‐Kul. Here, modern denudation rates are higher than 10Be‐derived paleo‐denudation rates, which are comparable in magnitude with the long‐term exhumation rates inferred from AFT and AHe. We propose that denudation in the region, particularly in the Terskey range, remained relatively steady during the Neogene and early Pleistocene. Denudation increased due to glacial‐interglacial cycles in the Quaternary, but this occurred after the onset and intensification of the Northern Hemisphere glaciations at 2.7 Ma. Plain Language Summary: Tectonic forces create mountains, while climatically modulated erosion breaks them down into sediment that rivers carry to the final depositional basin. This cycle affects global climate over long periods, but it's unclear whether mountain uplift causes climate change or if climate cooling leads to faster erosion and mountain uplift. To tackle these questions, we explore temporal and spatial changes in rates of denudation in the northern Pamir—Tian Shan region and find that rates remained steady during the Neogene and early Pleistocene but increased due to glacial‐interglacial cycles in the Quaternary. We also find that modern denudation rates decrease from west to east. This suggests that tectonic deformation controls denudation in the northern Pamir and western Tian Shan, while further east the denudational response of the landscape to Quaternary glaciations is more pronounced and reflected in our data. Dominant controls on modern denudation rates vary across the mountain range and reflect local factors. Our results highlight how the evolution of mountain belts strongly depends on denudation, which reflects complex interactions between tectonics, climatic changes, and surface processes, and show how in the northern Pamir—Tian Shan region, climate cooling during the Quaternary period resulted in faster erosion rates. Key Points: Modern denudation rates are higher than paleo‐denudation rates from 2.0 to 2.7 Ma and exhumation rates inferred from thermochronologyDenudation in the Terskey range remained steady during the Neogene and early Pleistocene and then increased in the Quaternary after 2.0 MaThe denudational response to Quaternary glaciations is detectable in the Kyrgyz and Chinese portions of the Tian Shan [ABSTRACT FROM AUTHOR]