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International audience; The physical, sedimentological, mineralogical and elemental geochemical properties of sediment cores AMD1803-02BC and 01PC from the Cape Norton Shaw Inlet were investigated to reconstruct glacial sediment discharges from southeastern Manson Icefield and document the impact of ice–ocean interactions on the sediment dynamics and opening of the North Water Polynya (NOW) in northwestern Baffin Bay since the last deglaciation. Laminated glaciomarine sediments rich in quartz and feldspar are observed prior to 11 cal. ka BP and were probably deposited by hyperpycnal currents triggered by the local retreat of the southern margin of the Innuitian Ice. Detrital proxies suggest that Early Holocene sediment dynamics were mainly influenced by sea ice and iceberg rafting and meltwater discharges related to the deglaciation of eastern Smith (~11 to 10.65 cal. ka BP) and Jones (~10.7 cal. ka BP) sounds. This also provides an upper limit to the timing of formation of the NOW. The high detrital carbonate contents during 8.8 to 6.6 cal. ka BP confirm that enhanced carbonate-rich sediment export from Nares Strait to northern Baffin Bay occurred during and after the deglaciation of Kennedy Channel (8.8 to 8.2 cal. ka BP). Canadian Shield sediment inputs have dominated since 6.6 cal. ka BP, indicating that sedimentation is mainly influenced by Cape Norton Shaw glacier discharges. The lower level of sedimentation recorded in core 01PC during the Middle to Late Holocene suggests an accelerated landward retreat of the Cape Norton Shaw glaciers in response to warmer marine conditions. During the Neoglacial period, higher sedimentation rates and detrital proxies in the cores suggest increased glacial erosional processes, probably associated with the long-term declines in boreal summer insolation and glacier growth. Finally, mineralogical and grain-size data in core 02BC support the idea that increased Arctic atmospheric temperatures have had an important influence on the glacial dynamics during the industrial period.

International audience

The evolution of carnassial teeth in mammals, especially in the Carnivora, has been subject of many morphometric and some dental topographic studies. Here, we use a combination of dental topographic analysis (Dirichlet normal energy) and 3D geometric morphometrics of less and high carnassialized lower teeth of carnivoran, dasyuromorph and hyaenodont taxa. Carnassial crown curvature, as indicated by Dirichlet normal energy, is high in lesser carnassialized teeth and low in higher carnassialized teeth, where it is influenced by the reduction of crown features such as cusps and crests. PC1 of the geometric morphometric analysis is linked to enlargement of the carnassial blade, reduction of the talonid crushing basin and an increasingly asymmetric cervix line with an enlarged mesial flexure in more carnassialized teeth. Distribution of PC1 values further indicates that along the tooth row of dasyuromorphs (m2-m4) and hyaenodonts (m1-m3) the most distal carnassial is the most carnassialized (principal carnassial), and in most taxa with overall higher carnassialized teeth, carnassialization successively increases from the anterior to the posterior tooth position along the tooth row. PC2 indicates that a longitudinal elongated carnassial is present in caniforms and in unspecialized feliforms, which separates these taxa in morphospace from all dasyuromorphs, hyaenodonts and specialized feliforms. An ancestral state reconstruction shows that this longitudinal elongation may be a plesiomorphic ancestral state for the Carnivora, which is different from the Dasyuromorphia and the Hyaenodonta. This elongation, enabling the presence of a longitudinally aligned carnassial blade as well as a complete talonid basin, might have provided the Carnivora with an advantage in terms of adaptive versatility.

We present new high-resolution pollen records combined with palaeoceanographic proxies from the same samples in deep-sea cores SHAK06-5K and MD01-2444 on the southwestern Iberian Margin, documenting regional vegetation responses to orbital and millennial-scale climate changes over the last 28 ka. The chronology of these records is based on high-resolution radiocarbon dates of monospecific samples of the planktonic foraminifera Globigerina bulloides, measured from SHAK06-5K and MD01-2444 and aligned using an automated stratigraphical alignment method. Changes in temperate and steppe vegetation during Marine Isotope Stage 2 are closely coupled with sea surface temperature (SST) and global ice-volume changes. The peak expansion of thermophilous woodland between similar to 10.1 and 8.4 cal ka BP lags behind the boreal summer insolation maximum by similar to 2 ka, possibly arising from residual high-latitude ice-sheets into the Holocene. Rapid changes in pollen percentages are coeval with abrupt transitions in SSTs, precipitation and winter temperature at the onset and end of Heinrich Stadial 2, the ice-rafted debris event and end of Heinrich Stadial 1, and the onset of the Younger Dryas, suggesting extrinsically forced southwestern Iberian ecosystem changes by abrupt North Atlantic climate events. In contrast, the abrupt decline in thermophilous elements at similar to 7.8 cal ka BP indicates an intrinsically mediated abrupt vegetation response to the gradually declining boreal insolation, potentially resulting from the crossing of a seasonality of precipitation threshold. (C) 2021 The Authors. Journal of Quaternary Science Published by John Wiley & Sons, Ltd., Journal of Quaternary Science, 37 (3), ISSN:0267-8179, ISSN:1099-1417

Varanopids are a group of Palaeozoic terrestrial amniotes which represent one of the earliest-diverging groups of synapsids, but their palaeoneurology has gone largely unstudied and recent analyses have challenged their traditional placement within synapsids. We utilized computed tomography (CT) to study the virtual cranial and otic endocasts of six varanopids, including representative taxa of both mycterosaurines and varanodontines. Our results show that the varanopid brain is largely plesiomorphic, being tubular in shape and showing no expansion of the cerebrum or olfactory bulbs, but is distinct in showing highly expanded floccular fossae. The housing of the varanopid bony labyrinth is also distinct, in that the labyrinth is bounded almost entirely by the supraoccipital-opisthotic complex, with the prootic only bordering the ventral portion of the vestibule. The bony labyrinth is surprisingly well-ossified, clearly preserving the elliptical, sub-orthogonal canals, prominent ampullae, and the short, undifferentiated vestibule; this high degree of ossification is similar to that seen in therapsid synapsids and supports the traditional placement of varanopids within Synapsida. The enlarged anterior canal, together with the elliptical, orthogonal canals and enlarged floccular fossa, lend support for the fast head movements indicated by the inferred predatory feeding mode of varanopids. Reconstructed neurosensory anatomy indicates that varanopids may have a much lower-frequency hearing range compared to more derived synapsids, suggesting that, despite gaining some active predatory features, varanopids retain plesiomorphic hearing capabilities. As a whole, our data reveal that the neuroanatomy of pelycosaur-grade synapsids is far more complex than previously anticipated.

International audience; While early maps are known from all over the world, the key questions always involve: what exactly do they show? And what spatial extent do they cover? In this context, we recently used 3D-modelling to re-examine a carved stone slab datable to the Early Bronze Age (c.2150–1600 BC) that was found at Saint-Bélec in Brittany. We show that the surface of the slab had been shaped in three dimensions to represent the relief of the surrounding landscape in which it was found, while several engraved motifs on it evoke contemporary structures known archaeologically. We argue that the Saint-Bélec slab represents an area of c.545 km2 corresponding to the extent of a prehistoric political entity. The carving and subsequent burying of the slab can be linked to the postulated rise and fall of hierarchical societies and raises many wider questions about socio-economic structures in temperate Europe at that time.

International audience; This study presents a new precise radiocarbon chronology for the World Heritage site of Sarvestan (SW Iran). The monument is a key construction in the history of architecture because it is a typical Sasanian construction built during the late Sasanian or early Islamic period. Previous attempts to date the monument have suggested the ages ranging from the middle Sasanian (fifth century CE) to early Abbasid (ninth century CE) era. These age estimations are based on the analysis of architectural plans and techniques, and a few radiocarbon dates with very large age uncertainties. This paper presents the results of a systematic radiocarbon dating of timbers in the walls and charcoals in plaster mortars used in the main dome of the monument. It further applies wiggle matching technique and R_Combine function to substantially reduce the age uncertainties in wood sections. The results indicate that a major construction work was undertaken sometime between 658 and 683 CE, the century of the invasion of Fars by Muslim Arabs. This finding pushes back the age of Sarvestan for two centuries and suggests that the monument was built at the transitional period between Sasanian to Islamic era. Sarvestan would have been an architectural project designed andpossibly initiated during the late Sasanian period but mainly accomplished during the second half of the seventh century CE. It can thus be considered a late Sasanian heritage in early Islamic period. Its construction at a time of political unrest further suggests that some areas of Fars may have benefited from certain socio-political stabilities during the expansion of Islaminto the east at mid- to late seventh century CE

In light of global warming and rising relative sea level (RSL), detailed reconstructions of RSL histories and their controlling processes are essential in order to manage coastal‐protection challenges. This study contributes to unravelling Holocene RSL change on the East Frisian North Sea coast in high resolution and with a new approach for the German Bight. For the first time, a transfer function (vertical error: 29.7 cm ≙ ~11% of the mean tidal range) for RSL change based on a combined training set of benthic foraminifers and ostracods from the back‐barrier tidal basin of Spiekeroog is applied to the Holocene record of the back‐barrier tidal basin of Norderney. The resulting RSL curve for the Norderney tidal basin is corrected for decompaction and shows a deceleration in RSL rise between 6000 and 5000 cal bp. The smallest possible error envelope (~1 m) results from the good suitability of salt‐marsh layers between 5000 and 4000 cal bp. The RSL curve provides an approach towards the closure of the common data gap of peat‐based curves for the southern North Sea related to a lack of basal peats in the youngest age range, and verifies regional differences in glacial isostatic adjustment., Volkswagen Foundation http://dx.doi.org/10.13039/501100001663, Niedersächsisches Ministerium für Wissenschaft und Kultur http://dx.doi.org/10.13039/501100010570

Sedimentary diatoms have been used to quantitatively reconstruct climate-related variables, such as temperature at different timescales. Even though temperature is often less of a key driver of diatom ecology than other environmental parameters (water chemistry), diatom inference models have been shown to be reliable in deducing past temperature trends. In addition, the oxygen isotope composition (δ18Odiatom) preserved in buried diatom frustules has demonstrated its potential to reflect climatic and hydrological conditions at the time of frustule formation. This study combines results from both diatom-based climate proxies to reconstruct summer water and mean annual air temperatures, and hydrological trends in Nettilling Lake, Baffin Island, from ca. 5000 to 500 cal a bp. Diatom-inferred temperatures revealed an overall ca. 2 °C cooling throughout the Late-Holocene. The δ18Odiatom values showed an increasing trend up to ca. 1900 cal a bp, where they reached their highest values (+24.8‰ at 15 cm) and thereafter decreased to their lowest values (+21.4‰ at 4 cm). These trends were linked to meltwater inflows associated with Penny Ice Cap thaw rate that was in turn controlled by regional climatic conditions which went from intensified cooling during the Neoglacial period to slight warming thereafter. Our results suggest that diatom- and diatom-isotope-based temperature and hydrological reconstructions can identify trends related to the natural climate system variability. The diatom oxygen isotopes are useful for paleoenvironmental studies of terrestrial aquatic ecosystems, but not for all hydrological systems are the ideal temperature proxy. Hence, the combination of proxies helps to disentangle temperature and hydrological effects for paleoclimatic reconstructions and may support future studies of postglacial environmental change in northern lakes.

International audience; PremiseThe conifer Geinitzia reichenbachii was a common member of the Cretaceous Laurasian floras. However, the histology of G. reichenbachii leafy axes was never described in detail, and our knowledge of its paleoecology remains very limited. Using new and exquisitely preserved silicified material from the Upper Cretaceous of western France, we describe G. reichenbachii from the gross morphology to the cellular scale, then discuss paleoecological and taphonomical implications.MethodsWe examined specimens from two localities in western France (Claix and Moragne) using propagation phase-contrast X-ray synchrotron microtomography.ResultsThe cuticle and the inner tissues of leafy axes are preserved in three dimensions. Epidermis, hypodermis, palisade parenchyma, spongy parenchyma, transfusion tracheids, and most of tissues of the vascular cylinder are clearly discernible. The numerous resin ducts are sometimes filled by persisting resin. Additionally, surfaces of some leaves preserved drops and flows of resin.ConclusionsDepositional environmental context combined with histological features of G. reichenbachii suggest that this conifer was adapted to a range of marginal-littoral ecosystems including those open to the sea paleoenvironments and innermost ones influenced by strong continental inputs. Geinitzia reichenbachii was adapted to withstand intense sunlight, hot temperatures coupled with salty sea wind, and dry conditions. The frequent amber-bearing beds in the Cretaceous from western France with Geinitzia as a main component of the associated floras raises the possibility of a role for Geinitzia in the production of the “Charentese amber”.

In 2017, a luxury bronze bucket was discovered nearKladina village in the Czech Republic. The bucket isdated to the ninth century BCE, and it is a unique arte-fact, having no parallel in Europe. Stylistically, it is a“transition type” dated between the Late Bronze Age(11th–10thcentury BCE) and the Hallstatt Period(eighth–sixth century BCE). Detailed palynologicalanalysis of verdigris and soil infill of the bucket identi-fied a wide range of pollen grains belonging mainly toherbs, with bitter-sour properties, and cereals. Subse-quent chemical analysis by gas chromatography/massspectrometry of soil extracts revealed the presence ofthe compound miliacin that is a chemical marker ofmillet. Moreover, a starch analysis reveals the presenceof enzymatically modified starch grains. These data,with the help of archaeological knowledge, indicate that the original content may have been millet-basedfood/beverage with addition of herbs. We suggest thatthis luxury vessel, given the contents we have identified,was deposited, in the late spring/summer months ofthe year.

The tempo and mode of Homo sapiens dispersal in Eurasia and the demise of Neanderthals has sparked debate about the dynamics of Neanderthal extinction and its relationship to the arrival of H. sapiens. In Italy, the so-called ‘Transition’ from Neanderthals to H. sapiens is related to the Uluzzian technocomplex, i.e. the first archaeological evidence for modern human dispersal on the European continent. This paper illustrates the new chronology and stratigraphy of Uluzzo C, a rock shelter and Uluzzian key site located in the Uluzzo Bay in southern Italy, where excavations are ongoing, refining the cultural sequence known from previous excavations. Microstratigraphic investigation suggests that most of the deposit formed after dismantling of the vault of the rock shelter and due to wind input of loess deflated by the continental shelf. The occasional reactivation of the hydrology of the local karst system under more humid conditions further contributed to the formation of specific layers accumulating former Terra Rossa-type soil fragments. Superposed on sedimentary processes, strong bioturbation and the mobilization and recrystallization of calcite have been detected. Optically stimulated luminescence (OSL) ages from Uluzzo C Rock Shelter are congruent with previously published radiocarbon ages obtained on shell beads and tephrachronology from adjacent sites preserving the Uluzzian technocomplex such as Grotta del Cavallo, confirming the onset for the Uluzzian in the area to ca. 39.2–42.0 ka. The OSL chronology from Uluzzo C also provides a terminus post quem for the end of the Mousterian in the region, constraining the disappearance of the Neanderthals in that part of Italy to ≥46 ± 4 ka.

Our study focuses on the Holocene hydroclimate long-term trends in southern East Siberia and places them in the context of the adjacent areas of the Siberian taiga in the north and the arid central Asia in the south. We present a new record from the eutrophic mire, in the forest-steppe region, covering the last 9000 years. Our multi-proxy approach includes physiochemical (ash content, grain size, micro-charcoal, peat decomposition) and biological indicators (pollen, non-pollen palynomorphs, plant macrofossils, testate amoebae, molluscs). The record indicates increased humidity during the Holocene Thermal Maximum at 8150–7400 cal. a BP, and drier conditions with evidence for fires at 7400–5100 cal. a BP. Next, wetter conditions occurred at the coring site at 5100–1400 cal. a BP based on evidence of fluvial influence, which is consistent with other records in the wider region. A short-term dry episode occurred at 1400–1300 cal. a BP, followed by a wet Medieval Warm Period (1300–650 cal. a BP) and Little Ice Age (450–300 cal. a BP) and a moderately wet environment from 300 cal. a BP to the present day. These results are consistent with the previously published palaeoenvironmental reconstructions from the steppe and forest-steppe regions in the south of East and West Siberia and taken together reveal a common trend towards wetter conditions with a maximum wetness between 4500 and 3000 cal. a BP. This differs from the taiga region further north and from the Altai-Sayan Mountains and Kazakhstan Hills further south, which show the trend from dry to wet and then to drier conditions in the Holocene, and from the Trans-Baikal region where the Holocene trend is to drier conditions. This study supports the predominant influence of the North Atlantic on the regional palaeoclimate changes in the forest-steppe region of East Siberia during the Holocene.

The Kalahari Basin, southern Africa preserves a rich archeological record of human origins and evolution spanning the Early, Middle and Late Pleistocene. Since the 1930s, several stratified and dated archeological sites have been identified and investigated, together with numerous open‐air localities that provide landscape‐scale perspectives. However, next to recent discoveries from nearby coastal regions, the Kalahari Basin has remained peripheral to debates about the origins of Homo sapiens. Though the interior region of southern Africa is generally considered to be less suitable for hunter‐gatherer occupation than coastal and near‐coastal regions, especially during glacial periods, the archeological record documents human presence in the Kalahari Basin from the Early Pleistocene onwards, and the region is not abandoned during glacial phases. Furthermore, many significant behavioral innovations have an early origin in the Kalahari Basin, which adds support to poly‐centric, pan‐African models for the emergence of our species.

International audience; he ‘acanthodian’ fishes provide key anatomical insights into the deepest branches of the chondrichthyan stem group. We review the anatomy of the acanthodian Vernicomacanthus uncinatus from the Lochkovian (Lower Devonian, 419.2–410.8 Ma) of Scotland based on eight articulated fossils, one of which is newly described. Broadly, the anatomy of V. uncinatus fits with that of contemporaneous acanthodians such as Climatius and Parexus, with a head covered by robust tesserae, an enlarged postorbital scale, an armoured shoulder girdle, and many pairs of ventrolateral spines. However, it departs from this anatomy in key respects. Its pectoral fin spines are obliquely ridged and posteriorly denticulated, similarly to Carboniferous gyracanth stem-group chondrichthyans. Its scales consist of multiple anteroposteriorly aligned odontodes, similarly to many Palaeozoic ‘sharks’. And its endoskeletal shoulder girdle may have a posterolateral angle, previously observed only in shark-like chondrichthyans. We propose that the differences between V. uncinatus and its congeneric, V. waynensis, which include potentially phylogenetically significant characters of the shoulder girdle and spines, are sufficient to erect a new genus for V. waynensis:Dobunnacanthus gen. nov. The scales of Vernicomacanthus are identical to those of the ‘shark’ scale genus Altholepis, suggesting that some such scales may instead belong to taxa with acanthodian-like gross anatomies. Based on these scales we highlight potential patterns in chondrichthyan scale evolution, in particular the axial addition of odontodes. Anatomical similarities between Vernicomacanthus and gyracanths, highlighted by previous authors, may indicate the existence of a grade including these and similar acanthodian-grade taxa placed relatively crownwards in the chondrichthyan stem-group

Accumulations of fine sediments along continental shelf and deep-sea bathymetric contours, known as contourite drifts, form a sedimentary record that is dependent on oceanographic processes such as ocean-basin-scale circulation. A tool used to aid in interpretation of such deposits is the sortable silt hypothesis, which suggests that the mean size of the sortable silt (silt from 10-63 µm) within a deposit can be used as a proxy for current velocity. While the hypothesis has been applied to numerous drift deposits, it has not been extensively explored. Slow deposition rates of contourite drift systems make it difficult to study in the deep ocean, and past laboratory studies have not tested the full range of conditions or mechanisms that could lead to sorting. This study uses flume experiments and theory to examine how the mean sortable silt in a deposit is related to current velocity under the action of advective depositional sorting. Tests were conducted for a fixed amount of time with four suspended sediment mixtures and current velocities typical of deep-sea settings (5-25 cm/s). Developed beds were sampled at fixed locations from the entrance and sized. The deposit grain size fined downstream and coarsened with increasing velocity at a particular distance from the inlet. Simple theory was able to capture the observations. Regardless of bed morphology or source sediment mixture, the mean sortable silt in the deposit was related to velocity at a particular flume location across all sediment mixtures. The slope of the relationship between velocity and size was dependent on the distance between the inlet and location of interest. Despite the simplified nature of the study, and the limitations regarding the presumed variability in natural systems, these findings broadly support the validity of mean sortable as a proxy for paleocurrent velocity at a distance along a depositing current.

International audience; Periglacial rock walls are affected by an increase in rockfall activity attributed to permafrost degradation. While recent laboratory tests have asserted the role of permafrost in bedrock stability, linking experimental findings to field applications is hindered by the difficulty to assess bedrock temperature at observed rockfall locations and time. In this study, we simulated bedrock temperature for 209 rockfalls inventoried in the Mont Blanc massif between 2007 and 2015 and 209 000 random events artificially created at observed rockfall locations. Real and random events are then compared in a statistical analysis to determine the results significance. Permafrost conditions (or very close to 0 °C) were consistently found for all events with failure depth > 6 m, and for some events affecting depths from 4 to 6 m. Shallower events were likely not related to permafrost processes. Surface temperatures were significantly high up to at least 2 months prior to failure with the highest peaks in significance 1.5 to 2 months and 1 to 5 days before rockfalls. Similarly, temperature significances at scar depths were significantly high, but steadily decreasing, 1 day to 3 weeks before failure. The study confirms that warm permafrost areas (> -2 °C) are particularly prone to rockfalls, and that failures are a direct response to extraordinary high bedrock temperature in both frozen and unfrozen conditions. The results are promising for the development of a rockfall susceptibility index but uncertainty analysis encourages to use a greater rockfall sample and a different sample of random events.

The Storegga tsunami, dated in Norway to 8150±30 cal. years BP, hit many countries bordering the North Sea. Run‐ups of >30 m occurred and 1000s of kilometres of coast were impacted. Whilst recent modelling successfully generated a tsunami wave train, the wave heights and velocities, it under‐estimated wave run‐ups. Work presented here used luminescence to directly date the Storegga tsunami deposits at the type site of Maryton, Aberdeenshire in Scotland. It also undertook sedimentological characterization to establish provenance, and number and relative power of the tsunami waves. Tsunami model refinement used this to better understand coastal inundation. Luminescence ages successfully date Scottish Storegga tsunami deposits to 8100±250 years. Sedimentology showed that at Montrose, three tsunami waves came from the northeast or east, over‐ran pre‐existing marine sands and weathered igneous bedrock on the coastal plain. Incorporation of an inundation model predicts well a tsunami impacting on the Montrose Basin in terms of replicate direction and sediment size. However, under‐estimation of run‐up persisted requiring further consideration of palaeotopography and palaeo‐near‐shore bathymetry for it to agree with sedimentary evidence. Future model evolution incorporating this will be better able to inform on the hazard risk and potential impacts for future high‐magnitude submarine generated tsunami events. Publisher PDF

Surface benthic foraminiferal assemblages associated with cold‐water coral mounds and reefs from the Irish margin and Norwegian shelf (North‐east Atlantic) are for the first time compared quantitatively. Results indicate that the considered sites share a common assemblage, dominated by elevated epibenthic and distinct infaunal species. This surface assemblage is typical of environments that are subject to strong bottom‐water turbulence with enhanced food availability. It provides a benchmark for comparison with fossil benthic foraminiferal assemblages from past cold‐water coral environments. Similar to macrofaunal and megafaunal communities, surface benthic foraminiferal diversity is higher on reefs and mounds than in surrounding off‐mound/off‐reef sediments. Benthic foraminiferal diversity is highest within the living coral macrohabitat, possibly as a result of enhanced availability and variety of food sources, and ecological niche separation. Indeed, living coral generally thrives on the summits or flanks of reefs and mounds where food availability is most important. The second part discusses the use of fossil benthic foraminiferal assemblages as palaeoceanographic proxies from past cold‐water coral environments. The overview of previous observations demonstrates that benthic foraminifera are valuable tools to reconstruct past bottom‐water oxygenation, bottom‐water currents and surface productivity, all of which are key environmental variables controlling cold‐water coral growth. Moreover, the advantages of a detailed investigation of benthic foraminiferal assemblages within cold‐water coral environments are compared to other palaeoceanographic proxies. This study highlights that benthic foraminiferal assemblages are an often overlooked proxy within cold‐water coral environments, despite yielding valuable information.

Motivated to help improve the robustness of predictions of sea level rise, the BRITICE-CHRONO project advanced knowledge of the former British–Irish Ice Sheet, from 31 to 15 ka, so that it can be used as a data-rich environment to improve ice sheet modelling. The project comprised over 40 palaeoglaciologists, covering expertise in terrestrial and marine geology and geomorphology, geochronometric dating and the modelling of ice sheets and oceans. A systematic and directed campaign, organised across eight transects from the continental shelf edge to a short distance (10s of kilometres) onshore, was used to collect 914 samples which yielded 639 new ages, tripling the number of dated sites constraining the timing and rates of change of the collapsing ice sheet. This special issue synthesises these findings of ice advancing to the maximum extent and its subsequent retreat for each of the eight transects to produce definitive palaeogeographic reconstructions of ice margin positions across the marine to terrestrial transition. These results are used to understand the controls that drove or modulated ice sheet retreat. A further paper reports on how ice sheet modelling experiments and empirical data can be used in combination, and another probes the glaciological meaning of ice-rafted debris.

This study investigates the stratigraphical sequence of Cocina Cave (Spain) employing and testing for the first time the capability of rare earth elements as markers of human activities in caves. Located in Dos Aguas (Valencian Community, Spain), Cocina Cave is characterized by the presence of several Holocene archaeological deposits from the final Mesolithic to the present day and is a pivotal site for understanding the socio‐ecological dynamics of the last hunter‐gatherer inhabitants of the Iberian Peninsula and the transition to pastoral and agricultural economies in the Western Mediterranean. However, the identification of strata from particular time‐periods in the cave is often difficult due to the homogeneity of layers, the poor archaeological record in some strata and the presence of severe disturbance phenomena. The methodological approach of this study consisted of cross‐referencing rare earth elements and other chemical markers with the archaeological stratigraphical interpretation, in an attempt to not only support the identification of the anthropic contribution to the formation of Cocina Cave strata, but also to characterize and confirm different natural and occupational episodes, particularly those associated with hunter‐gatherer, early agriculturalist, and shepherd activities. Sediments were collected from different excavation areas and analysed for major elements, trace elements, rare earth elements (REE), soil organic matter (SOM) amounts and pH. Multivariate statistics were employed to group samples according to their elemental profile, and these were then compared to the archaeological temporal interpretation. The obtained results showed that REE amount and fractionation geochemical processes were regulated by carbonates, phosphates and pH. The use of REE as markers was particularly useful as their concentrations and their calculated ratios and anomaly distributions were demonstrated to be highly consistent with the archaeological stratigraphical interpretation.

The response of summer precipitation in the western U.S. to climate variability remains a subject of uncertainty. For example, paleoclimate records indicate the North American monsoon (NAM) was stronger and spatially more extensive during the Holocene, whereas recent modeling suggests a weakened NAM response to increasing temperatures. These illustrate diverging pictures of the NAM response to warming. Here, we examine summer precipitation in the southwestern U.S. related to Last Interglacial insolation forcing. Using a high-resolution climate model, we find that Eemian insolation forcing results in overall wetter conditions throughout most of the southwestern U.S, but significantly drier than present conditions over Arizona. The overall wetter conditions are associated with a northward shift of the anticyclonic circulation aloft and increased moisture in the lower and mid-troposphere during the Eemian. Increased advection of Gulf of Mexico moisture is responsible for increasing precipitation in New Mexico and the northern edges of the NAM region. Drier conditions over Arizona are likely related to reduced local convection associated with reduced vertical moisture transport. These results highlight the spatial complexity of the NAM response to increasing radiative forcing and allow a better understanding of monsoon dynamics and variability in response to a warming climate.

This paper examines how bathhouses of Roman villas in the north-western part of the Empire can further our understanding of the amount of penetration the Roman cultural sphere had in less urbanised regions. The articulation of these baths to the villa, whether integrated, attached to it or completely freestanding, indicates degrees of accessibility beyond the inhabitants of the house. Rather than being merely private bathrooms for an elite that wished to enjoy the commodities of the city in the countryside, villa baths were social hubs for intra-elite networking and possibly enabled a form of euergetism towards small rural communities in a landscape otherwise devoid of cities and small civic centres.

Aim Pollen has been used before to reconstruct Holocene plant diversity changes in broadly delimited regions such as continents and countries. In this study we ask whether finer-scale differences in plant diversity, which are of interest to biogeographers and ecologists, are also detectable in the fossil pollen record coming from a single, biogeographically complex region of temperate Europe. Location Central Europe (Czech Republic, Slovakia). Taxon Vascular plants. Methods Fossil pollen extracted from 18 high-quality profiles was used as a proxy of past plant diversity. Pollen counts of tree taxa were corrected by pollen productivities and pollen assemblages were resampled to 100 grains per sample and 150 grains per 500-year time window. SiZer analysis was used to test and visualize multi-scale diversity patterns. SiZer maps were compared using principal coordinate analysis, and linear modelling was used to identify the best predictors. Pollen composition was analysed using non-metric multidimensional scaling. K-means clustering and indicator species analysis were used to interpret ordination results. Results Mean Holocene plant diversity is significantly predicted by latitude, whilst its temporal pattern varies by biogeographical region. Major differences were found between the Mesic and Montane Hercynia (relatively low diversity, increasing only in the Late Holocene) and Pannonia, the Carpathians and the Warm Hercynia (higher diversity, increasing from the Early or Middle Holocene onwards). The low diversity in the Middle and Late Holocene is associated with the prevalence of woody and acidophilic taxa. High diversity is associated with numerous grassland and minerotrophic wetland taxa, crops and weeds. Main conclusions Plant diversity and its changes during the Holocene are geographically structured across temperate Europe. The main causes appear to be differences between biogeographical regions in the dynamics of landscape openness and vegetation composition. The differences reflect spatial patterns in climate and human impact and their temporal changes.

Plastic pollution is widespread throughout the marine environments representing a risk for ecosystems and human health when plastic enters the food chain. Understanding factors and processes controlling plastic distribution and accumulation is crucial to identify plastic hotspots. Gateways and straits can play an important role on transferring plastic debris at superficial and sea bottom level depending on the local water masses stratification.

Paleolithic antiquity of parietal art in Ignatievskaya cave, Southern Ural, is supported by its subject (Late Pleistocene animals) as well as by paleontological and palynological data, and 14C dates from cultural layers associated with artistic activity (17.8−16.3 cal ka BP; association is established by finds of ochre in these layers). However, three 14C dates of charcoal motifs yielded younger, Holocene ages (7.4−6.0 cal ka BP). In this study, we constrain the age of parietal art in the cave by 230Th dating of flowstone that brackets the paintings. Flowstone did not form in the cave between c. 78 and 10 ka BP, due to widespread permafrost in northern Eurasia at that time. Our 230Th dates do not support the middle Holocene age of art in Ignatievskaya cave and are consistent with its Upper Paleolithic antiquity instead.

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Uncertainties about landscape evolution under cold, nonglacial conditions raise a question fundamental to periglacial geomorphology: what and where are periglacial landscapes? To answer this, with an emphasis on lowland periglacial areas, the present study distinguishes between characteristic and polygenetic periglacial landscapes, and considers how complete is the footprint of periglaciation? Using a conceptual framework of landscape sensitivity and change, the study applies four geological criteria (periglacial persistence, extraglacial regions, ice‐rich substrates, and aggradation of sediment and permafrost) through the last 3.5 million years of the late Cenozoic to identify permafrost regions in the Northern Hemisphere. In limited areas of unglaciated permafrost regions are characteristic periglacial landscapes whose morphology has been adjusted essentially to present (i.e., Holocene interglacial) process conditions, namely thermokarst landscapes, and mixed periglacial–alluvial and periglacial–deltaic landscapes. More widespread in past and present permafrost regions are polygenetic periglacial landscapes, which inherit ancient landsurfaces on which periglacial landforms are superimposed to varying degrees, presently or previously. Such landscapes comprise relict accumulation plains and aprons, frost‐susceptible and nonfrost‐susceptible terrains, cryopediments, and glacial–periglacial landscapes. Periglaciation can produce topographic fingerprints at mesospatial scales (103–105 m): (1) relict accumulation plains and aprons form where long‐term sedimentation buried landsurfaces; and (2) plateaux with convexo–concave hillslopes and inset with valleys, formed by bedrock brecciation, mass wasting, and stream incision in frost‐susceptible terrain.

AIM: Understanding long‐term heathland development is key in mitigating their current attrition globally. However, such knowledge is limited in Australia and the wider Southern Hemisphere. We aim to identify potential climatic and environmental drivers of Holocene heathland development in temperate‐oceanic Australia (Bass Strait), and also assess the applicability of Iversen's conceptual model of interglacial vegetation development to the area. LOCATION: Bass Strait, southeast Australia. TAXON: Monotoca, Epacris, Sprengelia and Restionaceae. METHODS: We used multiple sedimentary pollen and charcoal records from truwana/Cape Barren Island (CBI) in Bass Strait to reconstruct vegetation and fire history. We also used rarefaction analysis on pollen records to estimate floristic richness for all sites, and magnetic susceptibility and organic content were derived for two of the four sites as proxies for local sedimentary changes. Reconstructed vegetation and fire histories were then compared to independent records of climate and sea‐level change in temperate Australia, using a Detrended Correspondence Analysis ordination, to identify major drivers of heathland development. RESULTS: Major heathland expansion occurred on truwana/CBI between the early and mid‐Holocene in response to sea‐level rise, high effective precipitation, reduced seasonality and increased Indigenous burning. Increasing seasonality, low effective precipitation, El Nino‐Southern Oscillation intensification, stable sea level, and decreased fire activity drove the expansion of scrub and woodland at the expense of heathland in the late Holocene. The overall vegetation development on truwana/CBI fits poorly with the classic Iversen conceptual model of interglacial vegetation development in the Northern Hemisphere, due to the significant role of interglacial sea‐level rise on truwana/CBI. Therefore, a modified model, which takes into account the role of sea‐level change, is proposed for Southern Hemisphere‐temperate‐oceanic settings. MAIN CONCLUSIONS: Heathland developments in both hemispheres reflect some level of homogeneity, considering the roles of increased Indigenous burning and reduced seasonality in both hemispheres. Frequent, controlled burning strategies are recommended to maintain heathland on truwana/CBI.