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The persistence and size of the Greenland Ice Sheet (GrIS) through the Pleistocene is uncertain. This is important because reconstructing changes in the GrIS determines its contribution to sea level rise during prior warm climate periods and informs future projections. To understand better the history of Greenland's ice, we analyzed glacial till collected in 1993 from below 3 km of ice at Summit, Greenland. The till contains plant fragments, wood, insect parts, fungi, and cosmogenic nuclides showing that the bed of the GrIS at Summit is a long-lived, stable land surface preserving a record of deposition, exposure, and interglacial ecosystems. Knowing that central Greenland was tundra-covered during the Pleistocene informs the understanding of Arctic biosphere response to deglaciation. [ABSTRACT FROM AUTHOR]

This study presents the results of a detailed paleoclimate investigation on stalagmite YL-1 (Yelini Cave, Türkiye). YL-1 grew between 117.13 (+0.57/−0.44) ka and 114.87 (+1.63/−2.89) ka within Greenland Stadial 26, indicating a positive moisture balance during the stadial conditions in this semi-arid region. Rainfall is significantly affected by sub-cloud and surface evaporation and decreasing net effective winter precipitation is recorded by high isotope values. Enriched δ18O and δ13C at 116.65 (+0.51/−0.39) ka are interpreted as a drought event that took place ca. 400 years before the end of the MIS 5e. This event, which was reported simultaneously in marine and terrestrial archives in the Northern Hemisphere, is a result of decreased cyclone activity linked to weakening of the Atlantic meridional overturning circulation. 87Sr/86Sr values of YL-1 are close to the host-rock values. Decreased 87Sr/86Sr ratio at 116.67 (+0.54/−0.38) ka reflects the intensified water–rock interaction due to lower precipitation. Along with prior calcite precipitation effect, this is also observed by increased Mg/Ca and Sr/Ca, while low P, Cu, Be, Y, and Zr concentrations indicate a lowered amount of soil-derived colloidal material. The MIS 5e/5d transition is marked by reduced insolation and enriched δ18O at 116.24 (+0.53/−0.86) ka. The Greenland Interstadial 25 phase at 115.87 (+0.83/−1.71) ka is represented by more negative δ18O and δ13C. [ABSTRACT FROM AUTHOR]

Mean Sortable Silt (SS) size records in the hemipelagic deposits at Site U1452 (IODP 354) in the lower Bengal Fan are presented here to reconstruct the bottom water circulation strengths in the Bay of Bengal (BoB) during the last 200 ka (Marine Isotopic Stage 1 to 6). To eliminate possible amplitude shifts in SS size due to terrestrial sediment flux or turbiditic interventions, sedimentation history at the site is decomposed using End Member Analysis (EMA). SS size record in the BoB is mostly unimpacted by the terrestrial sediment flux and turbidity current deposition; hence the size sorting signature in SS records is best described to have arisen from benthic boundary layer current intensity. SS size record in the BoB indicates reduced bottom water flow speed during glacials (MIS 2 and 6), concomitant with the greater import of Antarctic/ Southern Ocean (SO) derived deep waters and increased speed during interglacials (MIS 1, 3 and 5) corresponding to an increased proportion of Northern Atlantic derived deep water mass in the northern Indian Ocean. Glacial and stadial decline in flow speed reflects on the density reversal between two deep water mass end members in the SO and a shoaled Atlantic meridional overturning circulation (AMOC). On the other hand, faster flow speed during the climate optima at MIS 5.5 and other warm substages of MIS 5 as well as during the Holocene present a deep and strong AMOC. Reduced bottom water circulation strength in the BoB during the MIS 5.5 to 5.4 transition might have contributed to atmospheric CO2 drawdown and global cooling during the early stages of glacial inception along with deep circulation changes in the SO. Also, millennial-scale variability in circulation strength in the BoB is linked to oceanic frontal shift in high northern latitudes and deepwater formation manifesting in reduced flow strength associated with local cold anomalies (C28-C23), successively culminating into glacial inception at MIS 5.4. Reduced flow speed is also observed during some of the Heinrich events indicating a strong teleconnection between deep North Atlantic and BoB. Productivity changes in the BoB might as well have been influenced by variable fluxes of northern and southern sourced water mass during the last 200 ka. [ABSTRACT FROM AUTHOR]

The Deckenschotter is a fluvial to glaciofluvial gravel unit in northern Switzerland and southern Germany. The deposits are considered the oldest preserved glacial to interglacial Quaternary deposits in the northern Alpine foreland and are thus important geomorphological markers for landscape evolution. Nevertheless, the age of the deposits is only approximately known and subject to controversial debates. This study presents the results of an extensive palaeomagnetic investigation carried out on intercalated fine-grained sediments at 11 sites of the Höhere Deckenschotter (HDS) and at 5 sites of the Tiefere Deckenschotter (TDS). The HDS show reversed and normal magnetisations, indicating deposition > 0.773 Ma, while the TDS exhibit only normal directions. Age constraints for the different sites are discussed in the light of evidence from other studies. The study therefore clearly supports the efforts to determine the age of the Deckenschotter. As data from previous palaeomagnetic studies on the HDS and TDS have not been published or preserved, this is in fact the only data-based palaeomagnetic study available. [ABSTRACT FROM AUTHOR]

Pollen and carbon isotope data from Natural Trap Cave provides insights into the environmental conditions of the Bighorn Basin, in north-central Wyoming, USA during the time intervals 151.1 to 132.2 cal ka BP, 51.8 to 17.4 cal ka BP, and 10.4 cal ka BP to present. Similarities between the buildup of the penultimate and last glacial maxima include abundant Artemisia, Amaranthaceae, Asteraceae, and Poaceae pollen, which, when combined with high δ13C values (>−25.0‰) and low plant discrimination values (18.0–19.0‰) from sedimentary organic matter, indicate steppe-like, cold-dry conditions. Between 151 and 142.5 cal ka BP, abundant Poaceae associated with much lower δ13C values (−28.0‰ to −26.0‰) and higher plant discrimination values (19.0‰–21.0‰) could be indicative of relatively wet summers. Similarly, after 25 cal ka BP increases in Poaceae may indicate wet conditions during the growing season. Holocene conditions differ from the earlier sections of the record, with greater arboreal pollen abundance (i.e., Pinus), consistent with woodland expansion in the region. Carbon isotope data from sedimentary organic matter show the Holocene was more humid than the glacial conditions of the late Pleistocene. This is especially clear at the start of the Holocene when a large negative carbon isotope excursion (CIE, < −28.0‰) occurred, providing a distinct chemostratigraphic marker defining the Pleistocene-Holocene boundary within these cave sediments. The association of this CIE with a pronounced spike in Pinus pollen supports an interpretation of a short-lived interval (<1000 years) of extremely warm, wet, forested conditions at this site. [ABSTRACT FROM AUTHOR]

Mesopelagic fishes are an important element of marine food webs, a huge, still mostly untapped food resource and great contributors to the biological carbon pump, whose future under climate change scenarios is unknown. The shrinking of commercial fishes within decades has been an alarming observation, but its causes remain contended. Here, we investigate the effect of warming climate on mesopelagic fish size in the eastern Mediterranean Sea during a glacial–interglacial–glacial transition of the Middle Pleistocene (marine isotope stages 20–18; 814–712 kyr B.P.), which included a 4°C increase in global seawater temperature. Our results based on fossil otoliths show that the median size of lanternfishes, one of the most abundant groups of mesopelagic fishes in fossil and modern assemblages, declined by approximately 35% with climate warming at the community level. However, individual mesopelagic species showed different and often opposing trends in size across the studied time interval, suggesting that climate warming in the interglacial resulted in an ecological shift toward increased relative abundance of smaller sized mesopelagic fishes due to geographical and/or bathymetric distribution range shifts, and the size-dependent effects of warming. [ABSTRACT FROM AUTHOR]

Plant fossils serve as critical proxies for interpreting past climates and environments, offering insights into the history of biosphere and climatic conditions. Here we describe a large tracheophyte cast, as well as the sedimentological settings in which it is preserved, expanding the paleobotanical database of the Itararé Group and contributing to the understanding of the LPIA in the Paraná Basin. This fossil occurs in Ponta Grossa, Paraná state, Brazil, within sedimentary levels interpreted as glacially dominated and deposited during the Late Paleozoic Ice Age (LPIA). The plant macrofossil is preserved as a cast, and the log is vertically oriented with a slight inclination in relation to the bedding plane. Taphonomic data indicate an allochthonous preservation, suggesting that the log was transported from inland areas to a plain before final burial. The identification of the tracheophyte cast within these glacial beds suggests that even in a dominantly glacial context, there were periods of episodic climatic amelioration. This finding implies that the climatic conditions during the Mississippian were not uniformly harsh, allowing the growth of vegetation as represented by the reported tracheophyta. • Record of a tracheophyte cast in allochthonous preservation in the basal Itararé Group. • The tracheophyte cast indicates episodic climatic amelioration, suggesting periods of frost-free conditions. • Dynamic climate changes and its impact on vegetation establishment in the Paraná Basin. [ABSTRACT FROM AUTHOR]

The study of trace fossils in glacially-influenced margins provides valuable insights into the changes in palaeoclimate and palaeoceanography during glacial-interglacial periods, by providing biological and ecological data of the benthic environment. Here we present a comprehensive ichnofabric characterisation of a sediment core located on an inter-canyon ridge on the SW Grand Banks Slope off Newfoundland, covering the Late Pleistocene–Holocene period (0–∼23 ka). The core analysis reveals 12 ichnogenera and an escape structure, with Phymatoderma , Tasselia , and Zoophycos being prominent and relatively abundant at specific levels. By examining the distribution of bioturbation content and degree along the core, we establish a strong association between moderate to high bioturbation and cold periods. The Last Glacial Maximum exhibits the highest abundance and diversity of trace fossils, particularly the deposit-feeding Phymatoderma and the deposit-feeding/equilibrium trace Tasselia , indicating benthic adaptation to seasonal food input and relatively high sedimentation rates. Conversely, the warmer deglaciation period shows limited bioturbation. Salinity stress may account for the abrupt decline in bioturbation degree during the early deglaciation. Additionally, the occurrence of large-sized Zoophycos coincides with the Younger Dryas cold event during the last deglaciation. These findings highlight the complexity of palaeoceanographic conditions and benthic environments in proximal glacially-influenced sites compared to distal hemipelagic and pelagic sites. The interplay between down-slope processes (such as turbidity currents and hyperpycnal flows) and along-slope processes (like contour currents) plays a crucial role in shaping the unique sedimentological regime of depositional sites and subsequently affecting the ichnofauna in glacially-influenced margins. • Bioturbation of glacially-influenced sediments was analysed in core. • Deposition during the Last Glacial Maximum is well-bioturbated. • Various down-slope and along-slope processes determine the ichnofauna. • Salinity stress accounts for decline in bioturbation during the early deglaciation. • Ichnofabrics reflect adaptation to seasonal food input and high sedimentation rate. [ABSTRACT FROM AUTHOR]

Along the south coast of the North Island of New Zealand, elevated Pleistocene marine terraces provide evidence for vertical deformation associated with active crustal faults and the westward subduction of the Pacific Plate at the southern Hikurangi margin. We have reassessed the age and elevation of these terraces. Optically Stimulated Luminescence (OSL) data of their cover bed sediments (20 new ages) provide the first numerical ages for most of these terraces. Shore platform elevations have been surveyed using differential Global Navigation Satellite System (GNSS) measurements of the wave-cut bedrock straths underlying these terraces. These new data allow the terraces to be temporally correlated across the margin. Seven different-aged terraces were identified and mapped along the Wellington south coast; these are preserved discontinuously between the westernmost site at Tongue Point, and Ngawi near Cape Palliser, to the east. The OSL data indicate that most of these terraces formed at MIS 5a, 5c, 5e (Last Interglacial) and 7a. The terraces are best preserved within the Hikurangi margin forearc, where they decrease in altitude towards the west, indicating long wavelength, westward tectonic tilting. The terraces are locally offset by a number of active crustal faults, most notably the Wairarapa and Ohariu faults. [ABSTRACT FROM AUTHOR]

This article examines the interpretation and implications of Ipswichian (Eemian) Stage temperate deposits discovered by the British Geological Survey east of the Lincoln Gap in eastern England. The fluvial deposits underlie the Southrey Terrace at Coronation Farm, Southrey and The Hermitage, Stainfield in the River Witham valley. Previously unpublished palynological analyses indicate that the temperate deposits compliment published pollen, mollusc and coleopteran assemblages from the same localities. The deposit at Southrey represents Ipswichian (=Eemian) substages Ip IIb and III, whilst that at Stainfield represents the Ip IIb Substage. The combined sequences are compared to those at neighbouring localities in the Witham and Bain-tributary valleys at Tattershall Castle and Tattershall Thorpe. The implications of the correlation of the interglacial deposits provide a re-evaluation of the River Trent-Witham terrace sequence, demonstrating that the Southrey Terrace deposits are not the equivalent of the Late Wolstonian (=Saalian) Balderton Member, but the Middle Devensian (=Weichselian) Substage Fulbeck Member, upstream of Lincoln. This implies that the River Trent was potentially aligned northwards towards the Humber before the Ipswichian Stage interglacial. The revised correlation indicates that glaciation of the region did not occur in the Middle Wolstonian (MIS 8) but during the Late Wolstonian (MIS 6) Substage. [ABSTRACT FROM AUTHOR]

Climatic oscillations during the Pleistocene played a major role in shaping the spatial distribution and demographic dynamics of Earth's biota, including our own species. The Last Interglacial (LIG) or Eemian Period (ca. 130 to 115 thousand years B.P.) was particularly influential because this period of peak warmth led to the retreat of all ice sheets with concomitant changes in global sea level. The impact of these strong environmental changes on the spatial distribution of marine and terrestrial ecosystems was severe as revealed by fossil data and paleogeographic modeling. Here, we report the occurrence of an extant, inland mangrove ecosystem and demonstrate that it is a relict of the LIG. This ecosystem is currently confined to the banks of the freshwater San Pedro Mártir River in the interior of the Mexico-Guatemala El Petén rainforests, 170 km away from the nearest ocean coast but showing the plant composition and physiognomy typical of a coastal lagoon ecosystem. Integrating genomic, geologic, and floristic data with sea level modeling, we present evidence that this inland ecosystem reached its current location during the LIG and has persisted there in isolation ever since the oceans receded during the Wisconsin glaciation. Our study provides a snapshot of the Pleistocene peak warmth and reveals biotic evidence that sea levels substantially influenced landscapes and species ranges in the tropics during this period. [ABSTRACT FROM AUTHOR]

The relative warmth of mid-to-late Pleistocene interglacials on Greenland has remained unknown, leading to debates about the regional climate forcing that caused past retreat of the Greenland Ice Sheet (GrIS). We analyze the hydrogen isotopic composition of terrestrial biomarkers in Labrador Sea sediments through interglacials of the past 600,000 y to infer millennial-scale summer warmth on southern Greenland. Here, we reconstruct exceptionally warm summers in Marine Isotope Stage (MIS) 5e, concurrent with strong Northern Hemisphere summer insolation. In contrast, "superinterglacial" MIS11 demonstrated only moderate warmth, sustained throughout a prolonged interval of elevated atmospheric carbon dioxide. Strong inferred GrIS retreat during MIS11 relative to MIS5e suggests an indirect relationship between maximum summer temperature and cumulative interglacial mass loss, indicating strong GrIS sensitivity to duration of regional warmth and elevated atmospheric carbon dioxide. [ABSTRACT FROM AUTHOR]

Bunicontro, M.P. and Marcomini, S.C., 2021. Geomorphological evolution of the Patagonian coast surrounding the Golfo Nuevo (Chubut, Argentina) during Late Quaternary: Overview and new proposal. Journal of Coastal Research, 37(3), 528–543. Coconut Creek (Florida), ISSN 0749-0208. The main contribution of this paper is a new interpretation of the geomorphological evolution of the North Patagonian coast surrounding the Golfo Nuevo from Mid-to-Late Pleistocene until present. The proposed model shows how continental and marine landforms evolved during the Late Quaternary. According to this, the Golfo Nuevo depression formed during the Middle Pleistocene (>130 ka) above previous fluvial terraces, which are attributed to different stages of the Chubut river. Several pediment types and levels were also identified: (1) flanking pediment (level 1) associated with an ancient fluvial valley; (2) convergent pediment related to a previous depression of Golfo Nuevo (level 2), both assigned to Middle Pleistocene; and (3) a littoral pediment (level 3) linked to a Holocene highstand level. The height and position of accretion marine terraces are discussed, in addition to their previous dating. It can be assumed that Golfo San Matías was flooded twice as a consequence of marine transgressions (marine isotopic stage [MIS] 5 and MIS 1). Likewise, Golfo Nuevo and Golfo San José were affected only once, during the maximum Holocene transgression (MIS 1). This paper highlights the importance of reconstructing the geomorphological evolution of a coastal area of the Patagonia as a result of a combination of changes linked to sea-level variations (mainly associated with glacio-eustasy) and climate, paleo-shorelines records, and continental landforms through Late Quaternary. The proposed geomorphological model can be considered a novelty because of the complex integration of continental and marine landforms and the study of their relative relation. [ABSTRACT FROM AUTHOR]

Limited numbers of high-resolution records predate the Last Glacial Maximum (LGM) making it difficult to quantify the impacts of environmental changes prior to peak glaciation. We examined sediments from Last Canyon Cave in the Pryor Mountains of Montana and Wyoming to construct a >45 ka environmental record from pollen and stable isotope analysis. Artemisia pollen was hyper-abundant at the beginning of the record. Carbon isotope values of bulk organic matter (>40 ka) showed little variation (-25.3 ± 0.4‰) and were consistent with a arid C3 environment, similar to today. After 40 cal ka BP, Artemisia pollen decreased as herbaceous taxa increased toward the LGM. A significant decrease in δ13C values from 40–30 cal ka BP (~1.0‰) established a new baseline (-26.6 ± 0.2‰), suggesting cooler, seasonally wetter conditions prior to the LGM. These conditions persisted until variation in δ13C values increased significantly with post-glacial warming, marked by two spikes in values at 14.4 (-25.2‰) and 13.5 cal ka BP (-25.4‰) before δ13C values dropped to their lowest values (-26.9 ± 0.2‰) at the onset of the Younger Dryas (12.8 ka). These results provide insights into late Pleistocene conditions and ecological change in arid intermontane basins of the Rocky Mountains. [ABSTRACT FROM AUTHOR]

The Jigongshan (JGS) Paleolithic site in the middle reaches of the Yangtze River has two different cultural layers, namely, the upper (flake-tool industry) and lower (cobble-tool industry) cultural layers. JGS site is also among the few upper Paleolithic sites in the middle reaches of the Yangtze River with an absolute age. Peking University has performed a preliminary 14C dating at the site and found that the upper culture layer is approximately 10–20 ka, whereas the lower layer is older than 50 ka. To date the lower culture layer precisely, the standard quartz single-aliquot regenerative (SAR) dose-based optically stimulated luminescence (OSL) and thermally transferred OSL (TT-OSL) methods were used in this study. Results showed that the age of the upper culture layer is approximately 23 ± 2–38 ± 3 ka, whereas that of the lower culture layer is approximately 115 ± 9–149 ± 9 ka. The 14C and OSL dating methods showed huge differences in their results for the lower culture layer. Based on our dating results, we propose that the main part of the upper culture layer corresponds to the late MIS 3 to the early MIS 2 stages during the glacial period in L 1 unit in the Chinese loess sequence, whereas the lower culture layer corresponds to the late MIS 6 and the early MIS 5 stages during both glacial and interglacial periods in the upper L 2 and the lower S 1 units. A cultural gap of nearly 100 ka was observed between these two cultural layers; this gap is larger than what was expected. [ABSTRACT FROM AUTHOR]

This article examines the interpretation and implications of certain conifer - dominated pollen assemblages recorded in lowland England, at sites glaciated during the Middle Pleistocene Wolstonian Stage. Such assemblages indicate the absence of severely cold-climate during a predominantly cold period and the presence of northern temperate boreal-type forest. The unambiguous stratigraphical position of the sequences provides evidence of climatic change during the late Middle Pleistocene. Nine sequences are considered, six in the English West Midlands, and three in eastern England. Evidence for temperate climate, and at some, subsequent cold-climate (periglacial) conditions is present within deposits pre-dating Wolstonian-age glacial deposits. In the Midlands, Wolston Formation glacial sediments overlie deposits of a pre-existing river system, the Baginton Formation. The latter accumulated during the transition from boreal to subarctic conditions. Evidence is based on sequences at Mathon, Waverley Wood, Brandon, Brooksby, Witham-on-the-Hill, High Lodge and Barnham. Since the Wolstonian glaciation occurred during the Late Wolstonian Substage (= Late Saalian, Marine Isotope Stage [MIS] 6), the Baginton Formation must span the MIS 7/6 boundary. Reinterpretation of the sequences indicates that the temperate continental climate interval, termed here the Waverley Wood temperate event, potentially represents the latter part of MIS 7 (Substages 7a-c, or 7e). This correlation is supported by comparison with sites on the near Continent. The implications of these conclusions are presented. [ABSTRACT FROM AUTHOR]

Asexual hybrids are important model organisms for addressing questions in evolution and ecology, especially for understanding the role of hybridization in speciation. They are rare in nature and several hypotheses have been suggested to explain this. We use an asexual fish, the Amazon molly (Poecilia formosa), to establish the area in which it was formed via hybridization 125 000 years ago. Using species distribution models and climate models for the Last Interglacial (LIG) we found that model projections to the LIG show a similar map to the present climate model and parental species potentially overlapped in a relatively small area near Tampico, Mexico. This makes P. formosa one of a few hybrid species for which we know the parental species, the time of hybridization, and likely the place of hybridization. Based on the small area of overlap, our data is in agreement with the idea that asexual hybrids may be rare not because they are evolutionary dead ends but are formed rarely. [ABSTRACT FROM AUTHOR]

The Arctic climate was warmer than today at the last interglacial and the Holocene thermal optimum. To reveal the impact of past climate-warming events on the demographic history of an Arctic specialist, we examined both mitochondrial and nuclear genomic variation in the collared lemming (Dicrostonyx torquatus, Pallas), a keystone species in tundra communities, across its entire distribution in northern Eurasia. The ancestral phylogenetic position of the West Beringian group and divergence time estimates support the hypothesis of continental range contraction to a single refugial area located in West Beringia during high-magnitude warming of the last interglacial, followed by westward recolonization of northern Eurasia in the last glacial period. The West Beringian group harbors the highest mitogenome diversity and its inferred demography indicates a constantly large effective population size over the Late Pleistocene to Holocene. This suggests that northward forest expansion during recent warming of the Holocene thermal optimum did not affect the gene pool of the collared lemming in West Beringia but reduced genomic diversity and effective population size in all other regions of the Eurasian Arctic. Demographic inference from genomic diversity was corroborated by species distribution modeling showing reduction in species distribution during past climate warming. These conclusions are supported by recent paleoecological evidence suggesting smaller temperature increases and moderate northward forest advances in the extreme northeast of Eurasia during the Late Pleistocene-to- Holocene warming events. This study emphasizes the importance of West Beringia as a potential refugium for cold-adapted Arctic species under ongoing climate warming. [ABSTRACT FROM AUTHOR]

Aim: To investigate cerrado responses to glacial–interglacial climate change and the potential for connective rain forest corridors between the Atlantic Coastal Forest and Amazonian rain forest. Location: The crater lake of Serra Negra (18 °S, 46 °W) in Minas Gerais, Brazil. Taxon: 117 fossil pollen types, 22 non‐pollen palynomorphs were documented. Methods: We recovered 7.82 m of sediment from the lake, and analysed fossil pollen at 62 depth intervals throughout the core. We derived a chronology based on radiocarbon dating with simple rate extrapolation to the base of the core. Results: The c. 90,000‐year fossil record showed a trend towards cooler climates at the Last Glacial Maximum (LGM), but interstadial warming coupled with reduced evaporative stress allowed the expansion of woodlands under cool, moist conditions. Cool‐adapted trees were most abundant between c. 67,000 and 48,000 years ago. A cool cerrado‐like environment marked full glacial conditions between c. 48,000 and 34,000 years ago. The peak of the LGM between c. 34,000 and 17,000 years ago is inferred to have been dry as no sediment accumulated in the system. Main conclusions: Expanded ranges of cold‐tolerant forest taxa led to establishment of a series of assemblages without modern analogue. A system characteristic of modern cerrado was rare in the history of this site. Multiple forest expansions were observed, each differing in composition. The periods of forest abundance at Serra Negra were not temporally aligned with forest expansion in the Atlantic Coastal Forest, and did not provide a continuous corridor of similar forest that connected the cerrado to the Atlantic Coastal Forest. [ABSTRACT FROM AUTHOR]

A number of interglacial sections discovered in the eastern part of Lithuania and suggested as Snaigupėlė Interglacial were attributed to the Saalian Complex Stage of Middle Pleistocene. However, the exact stratigraphical position and correlation of these interglacial sections are still arguable. Recent investigations were performed to get a clearer insight into the stratigraphy and sedimentation palaeoenvironment of the Snaigupėlė Interglacial sediments outcropping in Buivydžiai section and included complex proxies: pollen, plant macrofossils, diatoms, loss on ignition, magnetic susceptibility and optically stimulated luminescence dating. Interglacial sediments occur at the lowermost part of the exposure and reach more than 7 m thick. Palaeobotanical investigations confirm deposition of studied sediments during the different climatic stages of the interglacial. An attempt at correlation between the Buivydžiai section vegetational changes with vegetational succession obtained from north-central Europe allowed finding out some similarities with the Schöningen/Lublinian Interglacial. The OSL dating results do not contradict such a proposition as the two sand samples lying below the interglacial gyttja show sedimentation of this layer during the 300.5 ± 20.9 ka and 317.3 ± 21.8 ka time or MIS 9. However, recently obtained data are insufficient for grounding the correlation of studied section. Certainly, additional chronostratigraphic investigations would be valuable and may contribute to the solution of the sediment age and correlation problem. [ABSTRACT FROM AUTHOR]

Throughout the Phanerozoic, numerous well-preserved fossiliferous sites have provided valuable insights into the evolution of ecosystems and organisms. Among these sites, the Lontras Shale Lagerstätte (LSL) within the Lontras Member in southern Brazil stands out as a rare glimpse into Carboniferous ecosystems of western Gondwana. The LSL is renowned for its diverse array of well-preserved fossils like insects, wood, fishes, larval cases, and poriferans, with different types of preservational pathways. Moreover, the Lontras Member is considered a maximum flooding surface that marks an interglacial warming peak of the final Late Paleozoic Ice Age, highlighting its paleoclimatological and paleogeographical relevance. However, the occurrence of fossils within the extensive Lontras Member is restricted to a few sites, raising questions about the factors influencing this constrained lateral and vertical distribution. Through meticulous literature review, this study aims not only to solidify the understanding of the Lontras Member's lithostratigraphy and paleontology but also to explore its broader implications and paleoenvironmental significance. We propose a comprehensive stratigraphic section for the Lontras Member, integrating local and regional sections from Santa Catarina and Paraná States, surveying paleontological sites and fossils exhaustively. By examining two additional fossil-rich sites in addition to the Lagerstätte outcrop, and analyzing vertical and horizontal distributions of the Member, we thoroughly explore the methodological, paleoenvironmental, and taphonomic factors that restricts this fossil record. This analysis extends beyond comparisons with paleontological insights from other units, locations, and Lagerstätten, encompassing modern analogous environments. The methodological biases are tied to stratigraphic focus, fieldwork scale, fossil size, and weathering degree of outcrops, constraining new fossil discoveries. Paleobiological and paleoclimatological factors, like transitional climatic conditions, limited organism diversity, inhospitable deep environments distant from the coast, and anoxic bottoms impact organism distribution and fossil recovery. The fossil transportability and the compositional resilience under widespread anoxia contributed as preservational constraints. While the LSL offers unique conditions for the proliferation and preservation of organisms, limiting the taphonomic window, facies of more energetic depositional conditions in other Lontras Member sites is more likely to harbor fossils, particularly transportable fragments and disarticulated pieces of chitinophosphatic or phosphatic composition. Addressing these biases unveils insights into flourishing ecosystems and organisms during this specific time period. [Display omitted] • The Lontras Member, a stratigraphic landmark, is vertically and horizontally extensive. • Fossil distribution in this unit is constrained to a Lagerstätte and two other sites. • Collection biases, paleobiological and taphonomic factors limit the fossil occurrence. • The taphonomic window of this Lagerstätte is restricted to this outcrop. • Transportable chitin/phosphatic bioclasts have better recovery odds in this unit. [ABSTRACT FROM AUTHOR]

Stable isotope geochemistry is a well-known tool for the investigation of palaeoclimate. The application of this methodology to molluscan carbonate materials has increasingly receiving more attention in recent decades, stimulating the development of numerous environmental reconstructions. Among the different habitats and shell species investigated so far, the freshwater are the ones that have received least attention. The scarcity of systematic studies on lacustrine and riverine molluscan species considerably limits the use of these remains to reconstruct the environmental conditions of inland palaeontological and archaeological sequences. The present study focuses on Bithynia tentaculata , a freshwater species abundant in the European Quaternary fossil record. The aim of the research is to validate the use of oxygen (δ18O) and carbon stable isotopes (δ13C) of this species as palaeoenvironmental proxies. For this purpose, shells and opercula from stratigraphic sequences of three palaeolakes in eastern Poland, formed during the Holsteinian Interglacial (MIS 11), are analysed. The intercorrelation between B. tentaculata and two other molluscan species, together with good agreement with the pollen record, reveal that δ18O and δ13C are suitable indicators of water temperature and humidity levels for lacustrine environments. These results pave the way for using B. tentaculata in further palaeoclimatic reconstructions. • δ18O and δ13C of B. tentaculata shells and opercula record environmental variations. • The record agrees well with reconstructions based on other mollusc species. • Achieved a multispecies and multiproxy reconstruction of MIS 11 in eastern Poland [ABSTRACT FROM AUTHOR]

Optimal foraging theory and diet breadth models often place large mammals in top-ranking positions due to their high-energy return. However, mass collection of small prey can result in comparable return rates, and dietary diversity is nutritionally beneficial on its own right. A growing body of evidence recovered from several sites in the Mediterranean Basin confirms Neanderthal use of small size prey. Slow-moving, tortoises are an easy catch, and human collection and consumption is demonstrated by taphonomic analysis. In Portugal, two key Middle Palaeolithic cave sites, Gruta da Oliveira and Gruta da Figueira Brava, provide pertinent evidence. Based on an improved osteometric method, in which long bone measurements are standardised and analysed together using the Logarithmic Size Index (LSI), it is possible to better gauge the contribution of tortoises to the diet and the human impact on the species' populations. At inland Gruta da Oliveira, a tendency towards the massive collection of tortoises, affecting the local population more severely, is apparent. At coastal Gruta da Figueira Brava, the data suggest opportunistic collection upon encounter, possibly due to the availability of a more diverse range of resources. • Improved osteometric method for tortoise analysis. • Coastal Gruta da Figueira Brava shows opportunistic tortoise collection. • Inland Gruta da Oliveira shows a tendency towards tortoise overexploitation. • Possible tortoise extinction in Iberia at the onset of the Marine Isotope Stage 4. [ABSTRACT FROM AUTHOR]

Abstract The Last Interglacial (c. 128,000 to 115,000 years ago) was the last time when global temperatures may have been higher than those of the Holocene, but little is known about vegetation change or paleoclimate during that period in Central America. A new fossil pollen record from the lowland setting of El Valle, Panama, spanned the period from 137,000 to 98,000 years ago. We used multivariate analysis of modern and fossil pollen samples to provide the first regional quantification of Last Interglacial temperature and precipitation change and found mean annual temperatures were c. 1–2 °C warmer than modern, while precipitation was mostly similar to modern. The montane genus Quercus was intermittently present throughout the interglacial period, leading to the inference that this dispersal-limited taxon was surviving in microrefugia. Both charcoal and the early successional genus Cecropia were noticeably rare in the last interglacial compared with the Holocene. The modern absence of Quercus from Central Panama does not appear to be the product of interglacial warming, but rather a result of dry conditions in the late Holocene and human activity. It is suggested that humans greatly increased fire frequency, thereby favoring Cecropia and eliminating Quercus from the lower portion of its elevational range. Highlights • The last interglacial in Panama was between 1 and 2 °C warmer than modern and contained both wet and dry oscillations. • Quercus (oaks) survived in microrefugia below their modern limit during the last interglacial in Panama • Quercus were important components of lower-montane forests in Panama prior to human actions. • Mid-Holocene forest clearance and burning caused a loss of Quercus from their lower range in Panama. [ABSTRACT FROM AUTHOR]

Abstract This study presents a new database of dental microwear features for extant bear species, which is used to interpret palaeodiet in brown bear (Ursus arctos) from the late Middle Pleistocene site of Grays Thurrock, U.K. Applying light stereomicroscopy techniques in dental microwear analysis, we highlight, for the first time, that the talonid area of the first lower molar (m1) in extant ursids is most effective in the differentiation of dietary ecospaces. Extant bear species can be separated into different parts of a dietary ecospace revealing microwear features that mirror their dietary preferences. Of particular note is the differentation of ecospaces within modern brown bear populations from different geographical regions and the potential for identifying seasonal variation in diet. The results demonstrate that the diet of thelate Middle Pleistocene brown bear from the interglacial site of Grays Thurrock was closely comparable to that of the modern U. arctos from northern Europe, the American black bear (Ursus americanus), and the sun bear (Helarctos malayanus). This suggests the dietary importance of fibrous food, as well as soft fruits and invertebrates and a small vertebrate component. This finding is in agreement with climatic conditions and habitats inferred for the MIS 9 interglacial. The creation and testing of a dental microwear database for all modern bear species provides a foundation for subsequent application to other extinct Pleistocene bear populations. Highlights • New and comprehensive dental microwear database for modern Ursidae is presented. • Talonid area of m1 is most effective in the differentiation of ursid ecospaces. • Dietary ecospaces were established for the extant species. • Dietary differences can be traced also in brown bears from different latitudes. • The ecospace and palaeodietary niche were established for the fossil Grays bears, UK. [ABSTRACT FROM AUTHOR]

Abstract The loess-paleosol sequence exposed in the Beregovoye section (southwest of the Crimean Peninsula) has been thoroughly studied. Detailed analysis of the paleosol morphology, physical properties and chemical composition, micromorphology and other characteristics made it possible to identify types of paleosols formed in the Pliocene and Pleistocene. The results obtained gave us an insight into the climate and environments of the past. According to them, the climate of the Pliocene optimum was extremely hot and wet, and the soil zonality was hardly pronounced practically over entire Central and Eastern Europe. At the final phase of the Pliocene the climate became drier, though the rainfall amount was still greater than in the Holocene. During the Early Pleistocene the soil development followed the Mediterranean type, the climate being still warm, though less humid than in the Pliocene. There are two peaks of catastrophic changes in the evolution of the climate and environments distinctly traceable in the Beregovoye section: first – corresponding to the global change recorded between the Pliocene and Pleistocene and second, falling on the initial phase of the modern (Holocene) soil formation. Highlights • There are two peaks of catastrophic changes in the evolution of the climate in the Beregovoye section. • The climate of the Pliocene optimum was extremely hot and wet. • The soil zonality was hardly pronounced over entire Central and Eastern Europe. • At the final phase of the Pliocene the climate became drier. [ABSTRACT FROM AUTHOR]

The Chaudière River region in the Appalachian Mountains of eastern Canada is approximately 700 km north of the southernmost Pleistocene glacial deposits in New York and New Jersey. Detailed compositional analyses of glacial and non-glacial sediments from stratigraphic exposures and more than 40 boreholes drilled to bedrock provide a compositionally constrained record of glacial events, which include deposits of one Marine Oxygen Isotope Stage (MIS) 6 and two post-MIS 5 glaciations. The glacial and associated proglacial deposits rest on compositionally distinctive, preglacial saprolite that is preserved in deeper valleys. These observations constrain interpretations of the glacial/Pleistocene history of the eastern United States and Canada. The fact that there is no unequivocal evidence of pre-MIS 6 till in the Chaudière River region, while there are well-documented pre-MIS 6 glacial deposits south of there and in the American Midwest, also has major climatic implications. The Laurentide Ice Sheet and its ancestors must have been more robust in the west in the early Pleistocene and in the east most recently. [ABSTRACT FROM AUTHOR]

The open cast mine at Schöningen, Germany, provides the opportunity to study climatic and environmental changes that occurred from the Middle Pleistocene until today. Therefore, researchers from several different institutes and disciplines have been collecting data here for more than 25 years. These studies not only take place on the basis of singular cores, but also mainly in the context of long cross sections through the mine reflecting large landscape areas and biotopes. The quantity as well as the quality of the finds is unique. The Lower Palaeolithic complex includes wooden artefacts, stone artefacts, bones with impact scars and cut marks as well as bone artefacts, charcoal, charred wood and heated flint. Moreover, the countless natural remains of plants (e.g. wood, seeds, roots and leaves), bones, eggshells, molluscs, insects, and microscopic organisms can be used as proxies to understand the landscape and climatic development in Central Europe during the Upper Middle Pleistocene. Schöningen provides the data from changing environments with rich biodiversity which Homo heidelbergensis adapted to over a period of thousands of years. Thus it offers new insights into the evolution of the capacities and mechanisms involved in the exploitation of resources and the settlements dynamics. Highlights • This paper summarizes the results of the last 25 years of research and implements the new interpretations of the recoveries. • This study offers insights into the exploitation of resources and settlements dynamics of Homo heidelbergensis. • Schöningen allows to study climate changes, the environment and hominin activities from ca. 300,000 years ago. [ABSTRACT FROM AUTHOR]

Characteristics of the seasonal and interannual sea surface temperature variability in the eastern equatorial Pacific (EEP) over last two interglacials, the Holocene and Eemian, are analyzed using transient climate simulations with the Kiel Climate Model. There is a tendency toward a strengthening of the seasonal as well as the El Niño/Southern Oscillation (ENSO)‐related variability from the early to the late interglacials. The weaker EEP sea surface temperature annual cycle during the early interglacials is mainly a result of insolation‐forced cooling during its warm phase and dynamically induced warming during its cold phase. Enhanced convection over northern South America weakens northeasterlies in the EEP leading to weaker equatorial upwelling, deeper thermocline and subsequent warming in this region. We show that a negative ENSO modulation of the annual cycle operates only on short timescales and does not affect their evolutions on orbital time scales where both ENSO and annual cycle show similar tendencies to increase. Plain Language Summary: Although the Sun crosses the equator twice a year, the sea surface temperature (SST) in the eastern equatorial Pacific (EEP) exhibits a distinct annual cycle. Therefore, in addition to the direct solar forcing, coupled ocean‐atmosphere processes must also be taken into consideration to explain the observed annual cycle of the EEP SST. The annual cycle is also an important factor for the seasonal phase locking of the El Niño/Southern Oscillation. The aim of this study is to identify dominant factors affecting the annual cycle and interannual variability in the EEP on geological time scales. For this purpose we analyze transient climate simulations of the last two interglacials, the Holocene (9,500–0 BP) and the Eemian (126,000–115,000 BP). We find that both El Niño/Southern Oscillation variability and the annual cycle of SST in the EEP tend to increase from the early to late interglacials. We will show that local radiative forcing and reorganized atmospheric circulation are dominant factors to modify the annual cycle. However, a relative contribution of these factors may vary within the year. Our research demonstrates that the mechanism of the present‐day annual cycle should be updated when considering long‐term variations of climate states on orbital time scales. Key Points: Both ENSO variability and the annual cycle of SST in the eastern tropical Pacific tend to increase from the early to late interglacialsDirect radiation forcing and dynamical processes are underlying factors to intensify annual cycle of the EEP SST through the interglacialsStrengthening of the annual cycle of the EEP SST is in agreement with reconstructed seasonal range of the eastern tropical Pacific SST [ABSTRACT FROM AUTHOR]

The micro- and macromorphological studies performed on the loess-soil sequences in the south of the East European Plain permitted to identify and describe the type of soil-formation processes that took part in the development of interstadial and interglacial paleosols. Four paleosol complexes are distinctly identified within the limits of the studied region: Vorona (MIS 13/15), Inzhavino (MIS 8/9 or MIS 10/11), Kamenka (MIS 6/7 or MIS 8/9), Mezin (MIS 5); besides, there are the Bryansk interstadial paleosol (MIS 3) and Rzhaksa interglacial paleosol (MIS 17), both well identifiable in the region. The results obtained are in general agreement with the earlier conclusions by Velichko et al. (2012) about a general reduction of heat and moisture supply and an increase in aridity from the earlier towards later stages of the Pleistocene. The new data revealed, however, a few differences from the earlier concept. To mention but one example, we have found that the Kamenka interglacial (MIS 7 or MIS 9) paleosols formed in environments more humid than those of the Likhvin interglacial (MIS 9 or MIS 11). [ABSTRACT FROM AUTHOR]

Abstract: Aim: To determine the palaeoecological influences of climate change and human land use on the spatial distribution patterns of Polylepis woodlands in the Andes. Location: Tropical Andes above 2,900 m between 2°S and 18°S of latitude. Methods: Pollen and charcoal data were gathered from 13 Andean lake sediment records and were rescaled by the maximum value in each site. The rescaled pollen data were used to estimate a mean abundance and coefficient of variation to show woodland expansions/contractions and woodland fragmentation over the last 20,000 years. The rescaled charcoal was displayed as a 200‐year moving median using 500‐year bins to infer the influence of fire on woodland dynamics at landscape scale. Pollen and charcoal were compared with speleothem, clastic flux and archaeological data to assess the influence of moisture balance, glacial activity and human impact on the spatial distribution of Polylepis woodlands. Results: Woodland expansion and fire were correlated with precipitation changes and glacier dynamics from c. 20 to 6 kcal bp (thousands of calibrated years before present). Charcoal abundances between 20 and 12 kcal bp were less common than from 12 kcal bp to modern. However, human‐induced fires were unlikely to be the main cause of a woodland decline centred at 11 kcal bp, as woodlands recovered from 10.5 to 9.5 kcal bp (about twofold increase). Charcoal peaks analogous to those that induced the woodland decline at 11 kcal bp were commonplace post‐9.5 kcal bp but did not trigger an equivalent woodland contraction. An increase in the coefficient of variation after c. 5.5 kcal bp suggests enhanced fragmentation and coincided with the shift from logistic to exponential growth of human populations. Over the last 1,000 years, Polylepis became hyper‐fragmented with over half of sites losing Polylepis from the record and with coefficients of variation paralleling those of glacial times. Main conclusions: Polylepis woodlands formed naturally patchy woodlands, rather than a continuous vegetation belt, prior to human occupation in the Andes. The main factors controlling pre‐human woodland dynamics were precipitation and landscape heterogeneity. Human activity led to hyper‐fragmentation during the last c. 1,000 years. [ABSTRACT FROM AUTHOR]

Brasenia Schreb. is a monotypic genus in the Cabombaceae, present nowadays on all continents except Europe and Antarctica. This thermophilous aquatic plant, which originated in the Tertiary, was a frequent element of aquatic plant life during the interglacial stages of the European Pleistocene. A systematic review of the palaeobotanical records of Brasenia pollen and seeds reveals its history in Europe from the Plio-Peistocene until the Eemian interglacial. Remains of Brasenia were typical for the climatic optima during each of these stages of the Pleistocene. In this paper the diversity of fossil Brasenia species is also shown. The most abundant and morphologically diverse seeds were found in sediments from eastern European sites. Brasenia species became extinct in Europe at the end of the last interglacial or at the beginning of the Weichselian glaciation. Different scenarios for their disappearance are proposed, including the specificity of the floral cycle, probable poor dispersal of seeds, or the scarcity of suitable water bodies for it to survive. [ABSTRACT FROM AUTHOR]

The mega-diverse, Mediterranean-type fynbos biome may be vulnerable to future changes in climate and associated fire regimes, in particular to increasing summer-drought intensity and associated potential expansion of adjacent semi-arid vegetation types. Studying Holocene vegetation dynamics at the fynbos–succulent karoo boundary may provide insights into the resilience or sensitivity of fynbos to climate change. In this study, fossil pollen, non-pollen palynomorphs and charcoal data spanning ~5500 to −50 cal. yr BP were generated from an accelerator mass spectrometer (AMS) radiocarbon-dated sediment core extracted directly at the present-day fynbos–succulent karoo biome boundary at Groenkloof, a site in the Kamiesberg Mountains of Namaqualand, South Africa. Contrary to expectations, during the Mid-Holocene Altithermal from 5480 to 4025 cal. yr BP, fynbos and fire thrived through summer moisture subsidies associated with enhanced sub-tropical easterly flow. Subsequent cooling from 4025 to 2005 cal. yr BP resulted in enhanced summer drought and overall fynbos biome contraction, though woody fynbos shrubs persisted through physiological adaptations to drought. Desert succulents typical of the succulent karoo, such as those of Aizoaceae and Crassulaceae, failed to colonise the emergent niche space, resulting in dominance of an ambiguous grassy, asteraceous fynbos. More recent wetting associated with the ‘Little Ice Age’ Holocene temperature minima from 695 to 100 cal. yr BP prompted a resurgence in fynbos abundance, but frequent fire driven by pastoralists appears to have reduced the fynbos community’s functional diversity. Palaeoecological data from the Kamiesberg suggest that both climatic buffering of mountain refugia and high physiological resistance among certain fynbos taxa have contributed to the biome’s long-term resilience. Summer rainfall associated with the sub-tropical easterlies has been key in maintaining eastern fynbos refugia in past interglacial temperature maxima. The data also suggest that pre-historic land use and resulting fire-regime manipulations have resulted in the development of a taxonomically and functionally simplified alternative fynbos ecosystem state. [ABSTRACT FROM AUTHOR]

Sea levels at the end of this century are projected to be 0.26–0.98 m higher than today. The upper end of this range, and even higher estimates, cannot be ruled out because of major uncertainties in the dynamic response of polar ice sheets to a warming climate. Here, we propose an ecological genetics approach that can provide insight into the past stability and configuration of the West Antarctic Ice Sheet (WAIS). We propose independent testing of the hypothesis that a trans-Antarctic seaway occurred at the last interglacial. Examination of the genomic signatures of bottom-dwelling marine species using the latest methods can provide an independent window into the integrity of the WAIS more than 100,000 years ago. Periods of connectivity facilitated by trans-Antarctic seaways could be revealed by dating coalescent events recorded in DNA. These methods allow alternative scenarios to be tested against a fit to genomic data. Ideal candidate taxa for this work would need to possess a circumpolar distribution, a benthic habitat, and some level of genetic structure indicated by phylogeographical investigation. The purpose of this perspective piece is to set out an ecological genetics method to help resolve when the West Antarctic Ice Shelf last collapsed. [ABSTRACT FROM AUTHOR]

Un-fragmented stratigraphic records of late Quaternary multiple incised valley systems are rarely preserved in the subsurface of alluvial-delta plains due to older valley reoccupation. The identification of a well-preserved incised valley fill succession beneath the southern interfluve of the Last Glacial Maximum Arno palaeovalley (northern Italy) represents an exceptional opportunity to examine in detail evolutionary trends of a Mediterranean system over multiple glacial-interglacial cycles. Through sedimentological and quantitative meiofauna (benthic foraminifera and ostracods) analyses of two reference cores (80 m and 100 m long) and stratigraphic correlations, a mid-Pleistocene palaeovalley, 5 km wide and 50 m deep, was reconstructed. Whereas valley filling is chronologically constrained to the penultimate interglacial (Marine Isotope Stage 7) by four electron spin resonance ages on bivalve shells ( Cerastoderma glaucum), its incision is tentatively correlated with the Marine Isotope Stage 8 sea-level fall. Above basal fluvial-channel gravels, the incised valley fill is formed by a mud-prone succession, up to 44 m thick, formed by a lower floodplain unit and an upper unit with brackish meiofauna that reflects the development of a wave-dominated estuary. Subtle meiofauna changes towards less confined conditions record two marine flooding episodes, chronologically linked to the internal Marine Isotope Stage 7 climate-eustatic variability. After the maximum transgressive phase, recorded by coastal sands, the interfluves were flooded around 200 ka (latest Marine Isotope Stage 7). The subsequent shift in river incision patterns, possibly driven by neotectonic activity, prevented valley reoccupation guiding the northward formation of the Last Glacial Maximum palaeovalley. The applied multivariate approach allowed the sedimentological characterization of the Marine Isotope Stage 7 and Marine Isotope Stage 1 palaeovalley fills, including shape, size and facies architecture, which revealed a consistent river-coastal system response over two non-consecutive glacial-interglacial cycles (Marine Isotope Stages 8 to 7 and Marine Isotope Stages 2 to 1). The recurring stacking pattern of facies documents a predominant control exerted on stratigraphy by Milankovitch and sub-Milankovitch glacio-eustatic oscillations across the late Quaternary period. [ABSTRACT FROM AUTHOR]

Changes in Earth's orbital parameters pace the Pleistocene glacial-interglacial cycles, although considerable ambiguity still remains over the interaction of the internal climatic variables, such as ice-sheet instability and ocean circulation that allow transitions into and out of an interglacial. Here, we analyse high-resolution planktic foraminiferal proxies including sea-surface temperature (SST) based on an Artificial Neural Network (ANN) across the last three terminations (TI, TII and TIII) and the subsequent interglacials (Holocene, Marine Isotope Stages (MIS) 5e and 7e) from IODP Site U1385, SW Iberian Margin. To demarcate the stadials and interstadials, we combined the faunal and SST records with existing data at Site U1385 including log (Ca/Ti) and benthic and planktic δ18O. The composite records reveal details of the last three terminations in terms of abrupt climatic events occurring during these terminations. Termination I included three well-known climatic events: Heinrich stadial (HS)1, Bølling/Allerød (B/A) complex & Younger Dryas (YD). Termination II was interrupted by only HS11. Termination III included HS8.2 and HS8.1 which show more resemblance to HS2 (a stadial prior to TI) and HS1, suggesting the YD is a unique feature of the last deglaciation. Additionally, TI and TII reveal similar durations (∼6 kyr) with rates of SST change (∼1.5 °C/kyr to ∼2.1 °C/kyr), whereas TIII represents a longer process (∼10 kyr) with a relatively slow rate of SST change (∼0.8 °C/kyr). The anatomy of stadials (HS1, HS2, HS11 & HS8.1) reveals a complex history ('W' shaped anatomy) with two or three cold phases sandwiching (a) brief warm event(s). The European ice-sheet melting possibly initiated the stadial cooling at the Iberian Margin followed by the mid-latitude summertime warming and the intermediate-depth water mass warming that probably induced the Laurentide ice-sheet melting resulting in the complex stadial pattern. Our records further reveal a major reorganization of the surface current system, oceanographic fronts and productivity conditions across these terminations. We also document broad similarities in the climatic evolution of Holocene, MIS 5e and 7e interglacials in terms of SST, surface productivity and current system. The long-term interglacial trends were superimposed by multiple brief cold events interrupting the Holocene (∼11.3, 9.9, 8.2, 7.1, 5.5, 2.5 ka), MIS 5e (C28, C27, C27', C27a, C27b, C26, C26', C25), and MIS 7e (∼238, 234, 231, 230 ka) interglacials. Integration of our records with benthic foraminiferal δ13C records from the Iberian Margin and central North Atlantic suggest fluctuations in the deep water convection process (which in turn were influenced by the conditions in subpolar gyre) possibly resulted in the brief cold events interrupting the interglacials at the Iberian Margin. • Surface ocean-climate changes off SW Iberian margin on centennial-millennial scale. • Sequence of climatic events interrupting the last three terminations is unique. • Surface ocean circulation showed a major reorganization across these terminations. • Stadials (HS1, HS2, HS11 & HS8.1) portrayed a complex history at IODP Site U1385. • MIS 7e showed lesser intra-interglacial variability than the Holocene & MIS 5e. [ABSTRACT FROM AUTHOR]

Interstadial and interglacial deposits including peat layers are widespread in Northern Europe and enable us to reconstruct the past climate and vegetation history. Such reconstructions require a reliable and precise chronological framework. Uranium series dating, sedimentological and palynological investigations were performed on a peat deposit at Wedel in Schleswig-Holstein. Previous palynological studies suggested a Middle Pleistocene age for these interglacial deposits. The sediment sequence including a fen peat of 130 cm thickness at a depth of 14-15 m below surface was drilled and cored. Palynological results correlate well to the late Holsteinian Interglacial, but the radiometric age determination failed due to U-series open system behaviour. Comparison of results obtained at Wedel with those from Holsteinian Interglacial deposits in Northern Germany reveals the weakness of numerical age determinations. Furthermore, a brief discussion on radiometric data available of the Middle Pleistocene Reinsdorf Interglacial peat deposits at Schoningen is given, as the laboratory has performed further quality assurance processes. A spike calibration led to new calculations on isotope activities, resulting in higher values shifted by 5-7 % and corrections on published data of the same order. The age of the Reinsdorf Interglacial peat deposit 13 II-2c5 cannot be maintained as the assigned errors inhibit the calculation of reasonable mean ages nearby the methodological age limits. [ABSTRACT FROM AUTHOR]

In order to reconstruct the environmental and climatic conditions of the last and present interglacials, this study has examined a 52 m-long core obtained from a coastal embayment (Chang-Le) on the west coast of Taiwan Strait. The analyses of particle size distributions, total carbon content, organic carbon isotope ratios, n -alkane indices and alkenones from the core reveal two periods of marine transgression. Together with the radiocarbon and optically simulated luminescence dating analyses, the environmental proxies indicate that the older marine sequence (M1) was deposited during the period of rising sea level in the early-to-middle part of MIS5e. The younger marine sequence (M2) was confirmed as a deposit formed during the stable sea level of the latter part of the present interglacial. The shallow marine facies and the abundant alkenones from M2 suggest a deeper water environment under full marine conditions during the last interglacial. The sub-tidal to intertidal facies and weak appearance of alkenones in M1 imply a shallow water environment under weak marine influence. Because the site was close to upland landscape, high input of terrigenous material for both periods is evident. The alkenone-based sea surface temperature (SST) reconstructions indicate that the SST during MIS5e fluctuated slightly around 28.1 °C, which is about one degree higher than that of MIS1, consistent with records from the northern coast of the South China Sea. The depositional conditions and the burial depths of the two marine sequences also provide hints for the local tectonic movements. [ABSTRACT FROM AUTHOR]

The sulfur biogeochemical cycle plays a key role in regulating Earth's surface redox through diverse abiotic and biological reactions that have distinctive stable isotopic fractionations. As such, variations in the sulfur isotopic composition (δ34S) of sedimentary sulfate and sulfide phases over Earth history can be used to infer substantive changes to the Earth's surface environment, including the rise of atmospheric oxygen. Such inferences assume that individual δ34S records reflect temporal changes in the global sulfur cycle; this assumption may be well grounded for sulfate-bearing minerals but is less well established for pyrite-based records. Here, we investigate alternative controls on the sedimentary sulfur isotopic composition of marine pyrite by examining a 300-m drill core of Mediterranean sediments deposited over the past 500,000 y and spanning the last five glacial--interglacial periods. Because this interval is far shorter than the residence time of marine sulfate, any change in the sulfur isotopic record preserved in pyrite (δ34Spyr) necessarily corresponds to local environmental changes. The stratigraphic variations (>76‰) in the isotopic data reported here are among the largest ever observed in pyrite, and are in phase with glacial--interglacial sea level and temperature changes. In this case, the dominant control appears to be glacial--interglacial variations in sedimentation rates. These results suggest that there exist important but previously overlooked depositional controls on sedimentary sulfur isotope records, especially associated with intervals of substantial sea level change. This work provides an important perspective on the origin of variability in such records and suggests meaningful paleoenvironmental information can be derived from pyrite δ34S records. [ABSTRACT FROM AUTHOR]

Thick halite intervals recovered by the Dead Sea Deep Drilling Project cores show evidence for severely arid climatic conditions in the eastern Mediterranean during the last three interglacials. In particular, the core interval corresponding to the peak of the last interglacial (Marine Isotope Stage 5e or MIS 5e) contains ∼30 m of salt over 85 m of core length, making this the driest known period in that region during the late Quaternary. This study reconstructs Dead Sea lake levels during the salt deposition intervals, based on water and salt budgets derived from the Dead Sea brine composition and the amount of salt in the core. Modern water and salt budgets indicate that halite precipitates only during declining lake levels, while the amount of dissolved Na + and Cl − accumulates during wetter intervals. Based on the compositions of Dead Sea brines from pore waters and halite fluid inclusions, we estimate that ∼12–16 cm of halite precipitated per meter of lake-level drop. During periods of halite precipitation, the Mg 2+ concentration increases and the Na + /Cl − ratio decreases in the lake. Our calculations indicate major lake-level drops of ∼170 m from lake levels of 320 and 310 m below sea level (mbsl) down to lake levels of ∼490 and ∼480 mbsl, during MIS 5e and the Holocene, respectively. These lake levels are much lower than typical interglacial lake levels of around 400 mbsl. These lake-level drops occurred as a result of major decreases in average fresh water runoff, to ∼40% of the modern value (pre-1964, before major fresh water diversions), reflecting severe droughts during which annual precipitation in Jerusalem was lower than 350 mm/y, compared to ∼600 mm/y today. Nevertheless, even during salt intervals, the changes in halite facies and the occurrence of alternating periods of halite and detritus in the Dead Sea core stratigraphy reflect fluctuations between drier and wetter conditions around our estimated average. The halite intervals include periods that are richer and poorer in halite, indicating (based on the sedimentation rate) that severe dry conditions with water availability as low as ∼20% of the present day, continued for periods of decades to centuries, and fluctuated with wetter conditions that spanned centuries to millennia when water availability was ∼50–100% of the present day. These conclusions have potential implications for the coming decades, as climate models predict greater aridity in the region. [ABSTRACT FROM AUTHOR]

The drilled Inter-Continental Drilling Project core at the deeps of the Dead Sea reveals thick sequences of halite deposits from the last interglacial period, reflecting prevailing arid conditions in the lake’s watershed. Here, we examine sequences of intercalating evaporates (halite or gypsum) and fine-detritus laminae and apply petrographic, micro-X-ray fluorescence, and statistical tools to establish in high-temporal resolution the hydroclimatic controls on the sedimentation in the last interglacial Dead Sea. The time series of the thickness of the best-recovered core sections of the layered halite, detritus, and gypsum reveals periodicities of ~11, 7–8, and 4–5 yr, pointing to a North Atlantic control and possibly solar influence on the hydrology of the Dead Sea watershed during the regionally arid period of the last interglacial period. Similar periodicities were detected in the last glacial and modern sedimentary sequences of the Dead Sea and other archives of the central Levant, indicating a persistent impact of the solar cycles on regional hydrology, possibly through the effects of the North Atlantic Oscillation. [ABSTRACT FROM PUBLISHER]

Climate variability during Pleistocene glacial/interglacial transitions is well documented in marine and ice-sheet isotopic records, but terrestrial records showing the continental response to these transitions are scarce, especially for earlier in the Pleistocene. Cyclic intervals of warm interglacial and cold glacial conditions preserved in terrestrial records such as lake sediments provide opportunities to probe the biosphere's response to climate change. In this study, we track climate and plant type changes, specifically the presence of C3 and C4 plants, using the abundance and δ 13 C signatures of leaf waxes in paleolacustrine sediments from Valles Caldera in New Mexico. Through these changes, we assess the response of vegetation to climate variability in southwestern North America through two mid-Pleistocene glacial/interglacial transitions (Marine Isotope Stage [MIS] 14/13 and 12/11). Leaf wax data show that the C3 forest taxa were dominant through the entire record whereas C4 plants, better adapted to warm conditions and competitive under water stress, are favored during warming and extended arid periods during interglacials. The δ 13 C signature in leaf wax n -alkanes suggests that C4 plants persisted in the watershed throughout the interglacials and that some summer rainfall (which is required to support C4 grasses) was maintained even during prolonged dry periods. The abundance and carbon isotope composition of leaf waxes together with new MBT/CBT (methylation index of branched tetraethers/cyclization index of branched tetraethers) temperature data confirm warmer and more arid conditions during MIS 13 than during MIS 11, in spite of relatively low greenhouse gas concentrations during MIS 13. This suggests that variations in incoming solar radiation have played a major role in regulating the surface temperature, regional hydrological systems and vegetation in southwestern North America, likely through changes in the North American Monsoon coupled with variations in the location of the mid-latitude westerlies. [ABSTRACT FROM AUTHOR]

Marine Isotope Stage (MIS) 5, between about 130 and 70 ka BP, is characterized by climate oscillations consisting of three interstadials and two stadials. Many climate simulations have been performed for the warmest MIS-5e period, but few has been made to cover the entire MIS-5 to investigate the climate variability during this long period. In this study, two sets of snapshot simulations by a step of 2 ka covering the whole MIS-5 period are performed with the model HadCM3 to investigate the relative impacts of insolation, CO 2 and Northern Hemisphere ice sheets on the East Asian climate variability. Our results show that precipitation and temperature in different subregions in East Asia have different sensitivity to astronomical forcing, CO 2 and ice sheets, in particular when seasonal and mean annual changes are concerned. The variability of temperature and precipitation within MIS-5 is mainly controlled by precession but their magnitudes are modulated by CO 2 and ice sheets. The impact of ice sheets on summer precipitation vary between subregions and is sensitive to ice sheet configurations and background insolation. The summer precipitation in southern China is more sensitive to ice sheets than in northern China. Moisture budget analysis show that insolation and CO 2 affect the summer precipitation by the dynamic and thermodynamic processes, respectively, and the impact of ice sheets is mainly through the vertical dynamic processes which is strongly associated with the ice sheet-induced wave train at the hemisphere scale. • Regional climate in East Asia have different sensitivity to forcings. • Precession controls internal variability of East Asian climate within MIS-5. • CO 2 and ice sheets modulate variation magnitude of East Asian climate. • Precipitation anomalies depend on ice sheet configurations and background insolation. [ABSTRACT FROM AUTHOR]

Five sediment cores from the Lomonosov Ridge and the Morris Jesup Rise north of Greenland show the history of sea-ice coverage and primary productivity over the last two glacial cycles. Variations in Manganese content, benthic and planktonic foraminifera, bioturbation, and trace fossil diversity are interpreted to reflect differences in sea-ice cover and sediment depositional conditions between the identified interglacials. Marine Isotope Stage (MIS) 1 and MIS 2 are represented by thin (<<5 cm) sediment units while the preceding interglacial MIS 5 and glacial MIS 6 are characterized by thick (10–20 cm) deposits. Foraminiferal abundances and bioturbation suggest that MIS 1 was generally characterized by severe sea-ice conditions north of Greenland while MIS 5 appears to have been considerably warmer with more open water, higher primary productivity, and higher sedimentation rates. Strengthened flow of Atlantic water along the northern continental shelf of Greenland rather than development of local polynyas is here suggested as a likely cause for the relatively warmer marine conditions during MIS 5 compared to MIS 1. The cores also suggest distinct differences between the glacial intervals MIS 2 and MIS 6. While MIS 6 is distinguished by a relatively thick sediment unit poor in foraminifera and with low Mn values, MIS 2 is practically missing. We speculate that this could be the effect from a paleocrystic sea-ice cover north of Greenland during MIS 2 that prevented sediment delivery from sea ice and icebergs. In contrast, the thick sequence deposited during MIS 6 indicates a longer glacial period with dynamic intervals characterized by huge drifting icebergs delivering ice rafted debris (IRD). A drastic shift from thinner sedimentary cycles where interglacial sediment parameters indicate more severe sea-ice conditions gave way to larger amplitude cycles with more open water indicators was observed around the boundary between MIS 7/8. This shift is in agreement with a sedimentary regime shift previously identified in the Eurasian Basin and may be an indicator for the growth of larger ice sheets on the Eurasian landmass during the penultimate glacial period. [ABSTRACT FROM AUTHOR]

Luminescence dating offers new opportunities to explore the evolution of Quaternary marine coastal facies and landforms. This review highlights the main advances in luminescence geochronology of interglacial coastal sediments through the analysis of 547 luminescence ages, most of which were published during the last decade. The majority of these reported luminescence investigations have been carried out along passive margin coasts. Since the turn of the century, the discovery of a normalization procedure known as Single Aliquot Regeneration (SAR) has drastically reduced data scatter and improved precision, with the consequence that quartz SAR optically-stimulated luminescence OSL has become the dating protocol of choice for the Last Interglacial (LIG) period. A more complex technique, known as thermally-transferred OSL (TT-OSL), is presumably proposed for dating older interglacials of the Mid-Pleistocene and beyond. Feldspar luminescence is increasingly being applied to dating Pleistocene sea level high stands due to a much higher dose saturation level than quartz OSL. The use of feldspar IRSL (Infrared-stimulated luminescence) is limited by the occurrence of variable, but ubiquitous anomalous fading (AF). Following the advent of AF-correction methods, several Middle Pleistocene sites have been amenable to dating, albeit with significant related uncertainties. Recently, new protocols involving the measurement of post-IR IRSL at elevated temperatures have yielded relatively coherent ages for interglacial sediments up to ca. 300 ka. Quartz OSL/TT-OSL, AF-corrected IRSL, and post-IR IRSL ages are generally correlated with periods of sea level high stands. A few ages are reported from the early and middle part of the Middle Pleistocene, as MIS11, 9 and more commonly MIS7 high stands are documented in strongly uplifting active margin coasts. However, by far the most obvious age peak corresponds to the end of the LIG. The MIS5e shoreline is probably the most studied and luminescence-dated coastal feature of all, as the chronology of the sea level markers is crucial to assess global eustatic sea level variations through the course of the last interglacial. Nevertheless, the observed abundance of young (100–120 ka) luminescence ages for presumed MIS5e sediments may underline methodological issues, and/or reflect the higher preservation potential of late regressive sequences. On the other hand, the occurrence of geographically distant reports of MIS5a high stand might reflect a true eustatic origin for this event. Age analysis supports the impression of general reliability of luminescence for the timing of former sea level high stands. There is a clear need to address issues in dose rate variability, in the phenomenology of fading in feldspar, and in the behaviour of luminescence growth with dose, both in laboratory and natural conditions. These could be addressed and properly evaluated by dating different minerals, as multiple or single grains, with consequent variable internal dose rates. More robust practices in the application of luminescence dating techniques could eventually constrain the age uncertainties to no better than 2–3%. Therefore, the strength of luminescence as a dating tool is more in terms of its extended age range and the ubiquity of datable material. [ABSTRACT FROM AUTHOR]

Based on stable isotope analyses of worldwide reference curves, it has long been apparent that duration, intensity and climatic conditions of Pleistocene interglacial periods were significantly diverse. As a consequence of negligible fresh, detrital material admixture during interglacials, the soil formation intensity and maturity of various kinds of past soils have been holding vital information on the environmental conditions at the time the soils formed. This, in turn, means that several physicochemical properties of soils allow us to reconstruct past climatic regimes. Loess-paleosol sequences in Hungary (Central Europe) provide insight into the cyclic nature of glacial-interglacial variations of the last 1 million years. The paleosoils have been recognized as the product of warmer and moister interglacials, when the (glacial) loess material was altered by chemical weathering and pedogenic processes. The gradual change from oldest red Mediterranean soils via forest and forest-steppe soils to steppe soils represents well the continuous decrease of chemical alteration of interglacial paleosoils determined by environmental factors and duration of soil formation. Pedogene units from MIS-21 to MIS-5 strata were analysed in the course of this study. Major element analyses were carried out to get a proper picture on the paleoenvironmental conditions. Geochemical transfer functions have been applied to derive mean annual precipitation and mean annual temperature. These kinds of quantitative data on past climate and the stratigraphic data allow us to fit our pedostratigraphic units into a global context. The present paper is aimed at providing new information on the various climatic and environmental characteristics of Pleistocene interglacial periods and soil forming processes. [ABSTRACT FROM AUTHOR]

Aim Patterns of genetic variation within freshwater fish populations may reflect the historical impact of climate change on either sea-level or environmental conditions. Past sea-level changes enlarged palaeodrainages and so connected currently isolated rivers, whereas changes in environmental conditions reduced forest cover and may have constrained the movement of fish specialized to this habitat. We assayed genetic variation in Hollandichthys multifasciatus, a freshwater fish endemic to the Atlantic Forest of coastal Brazil, to test the relative importance of these factors in shaping current patterns of genetic divergence. Location River drainages along the south-eastern Brazilian coast. Methods A GIS was used to reconstruct palaeodrainages during the Last Glacial Maximum (LGM). Niche modelling was used to infer areas of stability for the southern Atlantic Forest sensu stricto (present and LGM). The contribution of river connections inside or outside areas of stability was evaluated using a calibrated phylogeny, analyses of molecular variance, and Bayesian skyline plots from two mtDNA loci. Results Analyses of 182 individuals from 26 populations and 12 palaeodrainages indicated that structure associated with palaeodrainages explains 75% of the genetic variation among populations, with estimated divergence times occurring within the Pleistocene. The variation explained by palaeodrainages and estimated population sizes was unrelated to the ecological stability of the region. Main conclusions This study demonstrates the importance of Pleistocene palaeodrainages in structuring genetic divergence patterns. The analyses suggest that past connections due to sea-level retreat played a significant role in the diversification of the ichthyofauna along the Brazilian coastal drainages. Moreover, the lack of a signature of habitat stability in structuring genetic variation suggests that refugia may be less important in structuring genetic diversity for freshwater species than for terrestrial species. In addition, our work highlights the utility of a GIS-based approach to recover past connections among coastal basins. Understanding these connections is crucial for studying diversification of riverine organisms and for identifying areas of conservation priority. [ABSTRACT FROM AUTHOR]

Aim Patterns of genetic variation within freshwater fish populations may reflect the historical impact of climate change on either sea-level or environmental conditions. Past sea-level changes enlarged palaeodrainages and so connected currently isolated rivers, whereas changes in environmental conditions reduced forest cover and may have constrained the movement of fish specialized to this habitat. We assayed genetic variation in Hollandichthys multifasciatus, a freshwater fish endemic to the Atlantic Forest of coastal Brazil, to test the relative importance of these factors in shaping current patterns of genetic divergence. Location River drainages along the south-eastern Brazilian coast. Methods A GIS was used to reconstruct palaeodrainages during the Last Glacial Maximum (LGM). Niche modelling was used to infer areas of stability for the southern Atlantic Forest sensu stricto (present and LGM). The contribution of river connections inside or outside areas of stability was evaluated using a calibrated phylogeny, analyses of molecular variance, and Bayesian skyline plots from two mtDNA loci. Results Analyses of 182 individuals from 26 populations and 12 palaeodrainages indicated that structure associated with palaeodrainages explains 75% of the genetic variation among populations, with estimated divergence times occurring within the Pleistocene. The variation explained by palaeodrainages and estimated population sizes was unrelated to the ecological stability of the region. Main conclusions This study demonstrates the importance of Pleistocene palaeodrainages in structuring genetic divergence patterns. The analyses suggest that past connections due to sea-level retreat played a significant role in the diversification of the ichthyofauna along the Brazilian coastal drainages. Moreover, the lack of a signature of habitat stability in structuring genetic variation suggests that refugia may be less important in structuring genetic diversity for freshwater species than for terrestrial species. In addition, our work highlights the utility of a GIS-based approach to recover past connections among coastal basins. Understanding these connections is crucial for studying diversification of riverine organisms and for identifying areas of conservation priority. [ABSTRACT FROM AUTHOR]

Despite the large body of research devoted to understanding the role of Quaternary glacial cycles in the genetic divergence of European trees, the differential contribution of geographic isolation and/or environmental adaptation in creating population genetic divergence remains unexplored. In this study, we used a long-lived tree ( Taxus baccata) as a model species to investigate the impact of Quaternary climatic changes on genetic diversity via neutral (isolation-by-distance) and selective (isolation-by-adaptation) processes., We applied approximate Bayesian computation to genetic data to infer its demographic history, and combined this information with past and present climatic data to assess the role of environment and geography in the observed patterns of genetic structure., We found evidence that yew colonized Europe from the East, and that European samples diverged into two groups ( Western, Eastern) at the beginning of the Quaternary glaciations, c. 2.2 Myr before present. Apart from the expected effects of geographical isolation during glacials, we discovered a significant role of environmental adaptation during interglacials at the origin of genetic divergence between both groups., This process may be common in other organisms, providing new research lines to explore the effect of Quaternary climatic factors on present-day patterns of genetic diversity. [ABSTRACT FROM AUTHOR]

The nature of ocean redox chemistry between the Cryogenian Sturtian and Marinoan glaciations (ca. 663–654 Ma) is important for understanding the relationship between environmental conditions and the subsequent emergence and expansion of early animals. The Cryogenian-to-Ediacaran stratigraphic succession of the Nanhua Basin in South China provides a nearly complete sedimentary record of the Cryogenian, including a continuous record of interglacial sedimentation. Here, we present a high-resolution pyrite Fe isotope record for a ∼120-m-long drill-core (ZK105) through Sturtian glacial diamictites and the overlying interglacial sediments in the Nanhua Basin to explore changes in marine chemistry during the late Cryogenian. Our pyrite Fe isotope profile exhibits significant stratigraphic variation: Interval I, comprising middle to upper Tiesi'ao diamictites (correlative with the Sturtian glaciation), is characterized by light, modern seawater-like Fe isotope compositions; Interval II, comprising uppermost Tiesi'ao diamictites and the basal organic-rich Datangpo Formation, is characterized by an abrupt shift to heavier Fe isotope compositions; and Interval III, comprising organic-poor grey shales in the middle Datangpo Formation, is characterized by the return of lighter, seawater-like Fe isotope compositions. We infer that Interval I pyrite was deposited in a predominantly anoxic glacial Nanhua Basin through reaction of dissolved Fe 2+ and H 2 S mediated by microbial sulfate reduction (MSR). The shift to heavier pyrite Fe isotope values in Interval II is interpreted as partial oxidation of ferrous iron to ferric iron and subsequent near-quantitative reduction and transformation of Fe-oxyhydroxides to pyrite through coupling with oxidation of organic matter in the local diagenetic environment. In Interval III, near-quantitative oxidation of ferrous iron to Fe-oxyhydroxides followed by near-quantitative reduction and conversion to pyrite in the local diagenetic environment was likely responsible for the return of lighter, seawater-like Fe isotope compositions in pyrite. Our pyrite Fe isotope profile thus records increased oxygenation in the Nanhua Basin between the Sturtian and Marinoan glaciations. The increased oxygenation of Nanhua Basin seawater deduced from pyrite Fe isotopes could have resulted from either local or global controls. Further work will be needed to determine whether this increasing oxygenation extended to the global scale. [ABSTRACT FROM AUTHOR]