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The Larsemann Hills, near Prydz Bay is a key region to understand past glacial dynamics in East Antarctica. However, multi-proxy dating constraints for this area indicate an uncertain chronology for deglaciation history during the Last Glacial Period (LGP). In this paper, we report two 26Al exposure ages and eighteen 10Be exposure ages for bedrock samples to better understand past glacial histories. The minimum exposure ages range from 82.84 ± 4.67 ka to 15.1 ± 1.95 ka corresponding to Marine Isotope Stages (MIS) 5–2, and fourteen of these samples date from before the global Last Glacial Maximum (c. 19–26.5 ka). Analysis of 10Be and 26Al concentrations implies a complex deglaciation history, and surface lowering of bedrock may have caused systematic age underestimation. Further comparisons between two adjacent regions in the Mirror Peninsula reveal two major deglaciations involving the Lambert Glacier / Amery Ice Shelf System dated at 61.78 ka to 82.84 ka and 21.98 ka to 49.5 ka during the LGP. • We present new evidence for studying glacial history of Larsemann Hills, Antarctica. • Cosmogenic nuclides 10Be and 26Al dating method is applied for better analysis. • Two major deglaciation events occurred regionally within MIS 2–3 and MIS 4–5. • The exposure age and elevation show a highly significant positive correlation. • Multi-proxy and adjacent evidence are summarized and compared with this study. [ABSTRACT FROM AUTHOR]

Hainan Island in southern China is situated within the Indo-Burma biodiversity hotspot, and has attracted the attention of evolutionary biologists, geologists, and biogeographers. However, the palaeogeography of Hainan Island and its relationship with mainland China remains contested. In this paper, we report RAD-seq data for Engelhardia roxburghiana populations from Hainan Island and adjacent mainland areas to identify genetic diversity, structure, divergence time, and demographic dynamics over geologic time. Findings were assessed using climate model data to constrain suitable distribution areas. Results indicate that E. roxburghiana dispersed from the Chinese mainland to Hainan Island via a hypothetical land bridge during the late Eocene so that the drift of Hainan Island was impossible. We cast doubt on the hypothesis that Hainan Island was connected to Vietnam and Guangxi at this time. We emphasize that higher genetic diversity in the Yunnan-Guizhou Plateau and Chiang-nan regions is the result of mixed populations or the existence of refugia, and lower genetic diversity in the Indochina Peninsula is due to a historical bottleneck. From the late Eocene to Oligocene, the arid belt that dominated East Asia retreated, facilitating the expansion of E. roxburghiana from the Indochina Peninsula to southern China. The main diversification of E. roxburghiana occurred in the Miocene following the strengthening precipitation within the East Asian Summer Monsoon. Climatic oscillations during the Quaternary led to the contraction of E. roxburghiana in the Indochina Peninsula, with expansion after Last Glacial Period (LGP; 119 to 11.7 ka). Southern China has served as a refugium and continues to do so in the future. In summary, our study elucidates the evolutionary trajectory of E. roxburghiana through large-scale sampling, providing insights into the palaeogeography of Hainan Island and itsbiogeographic relationships with adjacent mainlands. • A land bridge facilitated the spread of Engelhardia roxburghiana from Chiang-nan to Hainan Island in the late Eocene. • Engelhardia roxburghiana 's evolution follows Asian climate shifts, spreading north as arid zones retreated. • The diversification of Engelhardia roxburghiana occurred concurrently with intensified EASM precipitation during the Miocene. • Southern China was the refugium during the Quaternary glaciations and continues to do so in the future. [ABSTRACT FROM AUTHOR]

Integration of late Quaternary continental and marine proxies allows improved reconstruction of palaeoenvironment and palaeoclimates models for the south-eastern coast of Brazil. In this paper, we analyse pollen, fern spores, and dinoflagellate cysts in a marine sediment core (GL74) over the last ∼109 kyr. Results showed that, between 109 and 89.5 kyr, low sea levels promoted the expansion of herbaceous taxa across open areas while climatic conditions were relatively warm and humid, as indicated by the high frequency of Atlantic rainforest Ombrophilous forest pollen types and abundant of fern spores. Between ∼79–49 kyr, higher concentrations of palynomorphs were recorded, which were likely related to the low relative sea level during the last glacial period. During this interval, there was a decrease in tree pollen grains and an increase in shrub and herbaceous pollen grains, indicating cold and relatively dry weather conditions. In the Holocene period, the low deposition of palynomorphs may have been influenced by the gradual submergence of the central part of the Brazilian coast. This process was associated with warm and humid climatic conditions, as suggested by the expansion of rainforests and the presence of hygrophyte/aquatic taxa and fern spores, as well as the retraction of grassland pollen types. Dinocyst assemblages suggest that nutrient-rich waters and/or the presence of upwelling cells were dominant between ∼109–88 kyr, but gradually reduced between 88 and 65 kyr (and/or ∼ 88–20 kyr) under the influence of subtropical fronts. The study culminated in the dominance of unproductive warm water in the upper column between 65 and 0.5 kyr. • Correlation of continental and marine proxies in south-eastern Brazil during the late Quaternary Late • Quaternary dynamics of the South Atlantic Ocean based on dinocysts • Reconstruction of palaeovegetation and palaeoclimate for the last ∼109 kyr along the southeast coast of Brazil [ABSTRACT FROM AUTHOR]

Abstract During the Quaternary several glaciations occurred in the mountain regions around the Mediterranean and, in recent years, new ages have better constrained their timing. However, this is not the case for the Apuan Alps, a high-rainfall mountain chain adjacent to the Mediterranean Sea. Here, in spite of the widespread evidence for glaciers, the complete lack of geochronological information hinders our understanding of glaciation history. In this paper, we utilize speleothem ages to better constrain the timing of these glacial features. We re-examine 293 uranium‑thorium ages from 19 speleothems collected in five caves at different elevations. After a period of very low growth between 160 and 132 ka, the analysed speleothems grew almost continuously to ~75 ka, this period was followed by intermittent growth with lower deposition rate and presence of hiatuses until ~12.5/12 ka. This is consistent with an ice coverage persisting over the Apuan Alps, inhibiting or interrupting the growth of speleothems via the limited availability of groundwater and the scarcity/absence of soils. This interval is much greater than the time interval that has previously been attributed to the existence of glaciers on the Apuan Alps, which has been assumed to be restricted to Marine Isotope Stage (MIS) 2. Instead, ice cover probably also appeared in the Apuan Alps during MIS 4. The phase of restarting of growth, which may implies the definitive or substantial glacier melts seem to predate the Holocene. Highlights • Speleothem growth curves used to better constrain the timing of glacial features. • 293 U\Th ages from 19 speleothems collected in five caves at different elevations. • Glacial expansion in the Apuan Alps was not only limited to the MIS2. [ABSTRACT FROM AUTHOR]

This paper presents the first detailed paleoclimate reconstruction of the latest Antarctic isotope maximum (AIM4, ~ 33–29 ka cal. BP) at 52°S in continental southeastern Argentine Patagonia. High-resolution sedimentological and geochemical analyses of sediments from the maar lake Potrok Aike (PTA) reveal a decrease in the thickness of flood-induced turbidites and a series of wind burst deposits during AIM4, both pointing to increasingly drier conditions. This interpretation is also supported by a significant amount of runoff-driven micropumices incorporated within the sediments that suggests a lower lake level with canyons incising thick tephra deposits around the lake. Increased gustiness and/or dust availability in southeast Patagonia, together with intensified Antarctic circumpolar circulation in the Drake Passage, dust deposition in the Scotia Sea and in Antarctica ice shelf, are consistent with a southward shift of the Southern Westerly Winds (SWW) during the AIM4. In contrast to other warmer AIMs, the SWW during the AIM4 did not migrate far enough south to generate upwelling in the Southern Ocean and they did not reach 52°S in SE Patagonia, as revealed by unchanged values of the rock-magnetic proxy of wind intensity obtained from the same PTA core. Nevertheless, the SWW displacement during AIM4 imposed drier conditions at 52°S in southeast Patagonia likely by blocking precipitation from the Atlantic Ocean, in a way similar to modern seasonal variations and the other Antarctic warm events. [ABSTRACT FROM AUTHOR]

The Ordovician-Silurian (O S) transition witnessed dramatic tectonic, climatic, marine, and biological coevolution, during which organic-rich black shale was widely deposited and is considered an important source rock. However, the potential links between the differential enrichment pattern of organic matter and climate fluctuations and paleoenvironmental evolution during this period are still unclear. In this paper, the Late Ordovician-early Silurian black shale in a JieLong (JL) section in South China was identified by graptolitic fossils, total organic carbon (TOC) content, X-ray diffraction (XRD), scanning electron microscopy (SEM) and geochemical analysis. The results show that the provenances of sedimentary rocks are all granodiorite-like. According to the variations in the TOC content and geochemical indicators, four layers are delineated. Under warm and humid climatic conditions, sea level rise and unstable seasonal upwelling led to Unit 1 organic matter enrichment controlled by high primary productivity, anoxic conditions and effective smectite production. Unit 2 organic matter burial was controlled by cold, arid and oxic environmental conditions, but primary productivity was still relatively high. After the end of the glacial period, warm and humid climatic conditions and rapid transgression were the main factors affecting the burial of organic matter in Unit 3. Under hot and humid climate conditions, higher terrigenous detrital inputs and unfavourable preservation environments, the dilution of organic matter in Unit 4 was accelerated. The corrected chemical index of alteration (CIA corr) values show that the study area experienced a climate change of alternating cold and warm conditions in response to the climate fluctuation during the glacial-interglacial period. The CIA corr value is negatively correlated with the TOC content, while the generation of available clay minerals (smectite) in warm and humid climates is usually consistent with the enhanced burial flux of organic matter, supporting the important role of climate fluctuations in the accumulation of organic matter. Finally, a comparison of the data from the present study with geochemical data from different profiles in South China reveals the role of climatic fluctuations during the O S transition in controlling paleoenvironmental evolution and organic matter enrichment, while such a heterogeneous factor is usually associated with global or regional geological events. Our study highlights this differential enrichment mechanism as a combined response of multiple factors and provides important implications for glacial-interglacial organic matter enrichment mechanisms. • Rapid changes of weathering indices imply climatic fluctuations during the Late Ordovician-Early Silurian. • Four different patterns were established for organic matter accumulation across the O/S. • Climate fluctuations and the heterogeneity nature of ocean systems explain the regional variations of OM accumulation. [ABSTRACT FROM AUTHOR]

Millennial-scale variations in the Asian monsoon vapor transport are always associated with long-term changes in monsoon rainfall according to the conventional understanding. However, recent advances in monsoon studies suggested that regional monsoon rainfall has different responses to monsoon vapor transport. This paper presents a comparison between monsoonal vapor and precipitation records along the path of the Asian summer monsoon vapor transport. Pedogenic carbonate δ 18 O values in both surface sediment and Holocene eolian and lacustrine sediments from the Shiyang River drainage basin were used to investigate the variations of the Asian monsoon vapor transport. Meanwhile, Holocene lake-level changes of the terminal lake were reconstructed to reflect the monsoon precipitation variability. The results show that millennial-scale monsoon vapor transport is in accordance with low-latitude summer insolation, while the increasing summer monsoon rainfall during the early Holocene lags the monsoon water vapor transport. In addition, the relatively cold oceans left over from glacial periods and slow melting of ice sheets may temper the onset of the rainfall. These findings can provide insights into the interpretation of the asynchronous Holocene records from lakes and caves in East Asia. [ABSTRACT FROM AUTHOR]

Abstract: In the regions surrounding the Qinghai Tibet Plateau, changes in erosion rates have been linked to the tectonics, climate and topography over different time scales. To understand the mechanisms governing the changes of erosion rates, it is important to study erosion rates by different methods and for different time scales. In inland drainage basins, deposition rates of terminal lake sediments can indicate basin-wide erosion rates at the millennial-scale. This paper presents three lake records of the Last Deglaciation and Holocene (Huahai Lake, Zhuye Lake and Yanchi Lake) from the Hexi Corridor, north of the Qilian Mountains, in arid China. Organic matter, terrestrial pollen concentrates, seeds, grasses and plant debris are used for conventional and AMS 14C dating. On the basis of 66 radiocarbon dates, lithology and grain-size, we infer relatively high basin-wide erosion rates during the Last Deglaciation and early Holocene in the three drainage basins, when the three lake sediments were seriously affected by reworking. The deposition rates were an order of magnitude or greater in these lakes during the Last Deglaciation and early Holocene than during the mid-to-late Holocene. During the transition period of the last glacial–interglacial cycle, significant climatic changes occurred in East and Central Asia, corresponding to the strengthening of the Asian summer monsoon and to increasing effective moisture in arid Central Asia, which can have strong impacts on basin-wide erosion rates north of the Qinghai Tibet Plateau. Moreover, melting glaciers in the Qilian Mountains probably also contributed to the high basin-wide erosion rates. At the same time, tectonic activity was not recognizable in the study area during that period. In the arid and semiarid regions surrounding the Qinghai Tibet Plateau, dramatic changes in erosion rates appear during the transition periods of the glacial–interglacial cycles, which illustrate the climatic controls on erosion rates at this time scale. [Copyright &y& Elsevier]

Abstract: In this paper, we make an inventory of geomorphic remnants of past glaciations, especially glacial stages that occurred just after the Last Glacial Maximum (LGM). More than 35 terrestrial cosmogenic radionuclide (TCR) ages were obtained, providing new chronological benchmarks for defining the transition between the LGM and the Holocene, thus answering some remaining questions in the southern French Alps (upper Durance catchment). TCR ages fit very well with the scenario defined in other parts of the European Alps: two main generations of post-LGM moraines were identified, highlighting a synchronicity of glacial responses during the Younger Dryas and the Preboreal. Indeed, the first generation we identified corresponds to the Younger Dryas period, while the second generation was shaped during the Preboreal period. They suggest that a relatively thick glacier tongue (300m thick) occupied the upper catchment until the end of the Lateglacial period. The glacier tongue disappeared at the very beginning of the Holocene, before a short glacial re-advance during the Preboreal period. This scenario is linked to a very low equilibrium line altitude (ELA) during the Younger Dryas and the Preboreal: located respectively 340 and 150m below the Little Ice Age (LIA) ELA. Collectively, the results highlight a significant west–east gradient in ELA, probably in relation to westerly and northwesterly winds. Finally, the deglaciation pattern in this area is similar to that of the western and northern Alps, and appears significantly different from the patterns found in the inner and eastern Alps (such as the Ubaye and Maritime Alps patterns). [Copyright &y& Elsevier]

Abstract: Latest Viséan brachiopod shells (Gigantoproductus sp.) from the Pedroches basin of SW Spain were sampled in order to obtain chemical and isotopic evidence that may help, first, to assess if primary geochemical and isotopical signals are preserved in these shells and, second, to reconstruct temporal variations in palaeoceanographic and palaeoclimatic conditions in northern Gondwana during this time span. Microtexture, cathodoluminescence (CL) and ultrastructure (under SEM) of the brachiopods were examined to avoid sampling of shell portions altered after deposition. Shell portions classified as non-luminescent (NL) and non-luminescent to slightly luminescent (NL–SL) present geochemical signatures within the ranges considered normal for Recent brachiopods that have not undergone significant diagenetic modification. These include low to undetectable Fe and Mn contents, high Sr values, and δ 18O values similar to those of carbonates in equilibrium with seawater. On the other hand, valve areas that are luminescent (L) or moderately luminescent with luminescent portions (ML–L) present higher Fe and Mn contents, lower Sr concentrations, and lower δ 18O values than those corresponding to NL and NL–SL shells. This suggests a greater diagenetic alteration of these portions and that they acted as microzones of reaction with the diagenetic fluids. Temporal trends through the studied interval show a spread in δ 13C values much lower than that observed for contemporaneous samples (up to 1.6‰), thus obscuring the δ 13C global signal at the time-scale resolution of this study. In contrast, the δ 18O record of brachiopod calcite (δ 18Oc) shows an overall increase of ∼1‰ (relative to V-PDB) from the oldest to the youngest samples. This is accompanied by a ∼30% decrease in Mg/Ca ratios of the brachiopod calcites, confirming that at least part of this shift in δ 18Oc was related to cooling. Combination of Mg/Ca and δ 18Oc proxies established in this paper, although not full-proof for brachiopods yet, allowed for the calculation of a temperature drop of ∼3.3 °C and a change in seawater δ 18Ow that becomes ∼0.4‰ more positive during this interval. The data are consistent with regional seawater cooling that accompanied an increase in continental ice volume, over a relatively short time period of <4 Myr. Comparison of the Carboniferous isotopic data from Spain with data compiled from Palaeotethyan basins suggests that this positive event in δ 18Oc during the Brigantian (latest Viséan) may be correlated worldwide. This synchronous global shift provides evidence for the onset of the Carboniferous glaciation in Gondwana during the Brigantian. [Copyright &y& Elsevier]

Abstract: The Lodève basin, which contains an exceptional long and nearly uninterrupted profile of Early to Late Permian continental red beds, is well correlated to the other European Permocarboniferous basins. Together they cover the time span from the Late Pennsylvanian to the Permian–Triassic boundary. Although these basins were placed within the equatorial belt for the whole Permian, several climatic changes are recorded in the sediments. Terrestrial sedimentation is governed by the interaction of climate and tectonics as well as by volcanism to a variable degree. Therefore, small scale climatic variations of the Milankovitch band are hardly discernable and if so, they could not be correlated between different basins. Indeed, larger scale climatic shifts could be identified. It is shown, that the shift from the Carboniferous icehouse to the Mesozoic warmhouse was a multi-stage process. This global warming resulted in a general aridisation of northern Pangea, indicated by outspreading playa and sabkha red beds, aeolianites and evaporites. Several short phases of increased humidity interrupted this trend, indicated by wet red beds, lake sediments and coal deposits. In central and southern Europe, these wet periods are traceable within the Late Stephanian/Lower Rotliegend (Gzhelian/Asselian), topmost Lower Rotliegend (Asselian/Sakmarian), Upper Rotliegend I (late Artinskian/early Kungurian) and Upper Rotliegend II/Zechstein (Wuchiapingian). The aridisation of the northern Pangea which accelerated near the Sakmarian/Artinskian transition is attributed to a reorganisation of the major ocean currents. Cold water currents along the western flank of the Pangea, indicated by the Permian chert event, blocks moisture transport from West onto the continent. During Roadian and Wordian the onset of an additional cold water current along the Cimmerian continents, blocks moisture transport from the East. Both phenomena together are responsible for the maximum of aridity at the Early to Middle Permian transition. Additionally, the equatorial climate has been affected by an increasing seasonality within the Late Pennsylvanian and Permian, caused by the wide shifting of the Zone of Inter-tropical Convergence (ITC) over the equator. Based on a new reconstruction of the Pangean assembly in this paper, climatic changes in the Permian are interpreted and causes of the arid-humid-arid shifts are examined. Phases of higher humidity are often related to events of global impact, like the waxing and waning of the Gondwanan glaciation, obtained in the South African Karoo Basin (Dwyka Group). But also regional events had strong climatic influence. The Zechstein transgression in the Northern and Southern Permian Basin as well as the Bellerophon transgression of the Southern Alps caused the wet phase in the Wuchiapingian. [Copyright &y& Elsevier]

Proximal alluvial sediments represent a useful sedimentary archive to reconstruct the tectono-climatic history of continental rift basins. However, poor dating of coarse fluvial successions usually prevents high-resolution distinction of tectonic and climatic processes, and thus good determination of process rates. This paper presents a dating study of Plio-Pleistocene Kalavryta river system during the early history of the Corinth Rift (northern Peloponnese, Greece) based on magnetostratigraphy and palynology. This river system developed across several active normal fault blocks that are now uplifted along the southern rift margin. The detailed sedimentary record constrains alluvial architectures from the proximal basin to the river outlet where small deltas built into a shallow lake. In four magnetostratigraphy sections the correlation to the reference scale relies on the identification of the Gauss/Matuyama magnetic reversal and biostratigraphic elements. The river system developed between about 3.6 to 1.8 Ma, with sediment accumulation rates (SARs) ranging from 0.40 to 0.75 mm yr−1. SAR is lower in the alluvial fans than in the deltaic system, and higher at the centre of the normal fault depocentres than at the fault tip. By comparison with worldwide Cenozoic SARs, our values are higher but lie in the same range as those determined in coarse alluvial foreland basins. Moreover, in the context of overfilled intra-mountainous rift basins, these rates are minimum values and can be used as a proxy for accommodation rate. Therefore, early rift stratal wedges and growth synclines attest high sedimentation rates and also high rates of tectonic processes. Finally, in the distal river system, floral compositions and changes of vegetation deduced from palynological data are coherent with alternating fluvio-deltaic and shallow lacustrine deposits, which are linked to relative base level variations. Dry/cool climate is preferentially recorded during periods of low lake level, while the warm/moist climate is mainly recorded in prodelta deposits during periods of high lake level. This correlation suggests that, despite the dominant control of active faulting, climate is a key control of syn -rift stratigraphic architectures. • Basal syn-rift succession in the western Corinth rift from 3.6 Ma and 1.8 Ma. • Sediment accumulation rates 0.40–0.75 mm yr−1 varying with the alluvial architectures. • High rates of processes explained by high sediment supply from the antecedent Kalavryta river system. • Pollen record in the deltaic succession with alternating vegetation of interglacial and glacial periods. • The Valimi palynology section: a rare climatic record in syn-rift alluvial succession. [ABSTRACT FROM AUTHOR]

This paper reviews quantitative biostratigraphic data from 101 petroleum exploration wells from the Malay, Sarawak and Sabah basins, and places the stratigraphy of each area into a precise chronostratigraphic framework comprising 41 transgressive-regressive depositional packages which are fully defined here. Each package is 'fingerprinted' by foraminiferal, nannofossil and palynological index fossils, and then tied to the global pattern of glacio-eustatic sea level and climate changes based on the global δ18O and δ13C datasets used to calibrate the geological timescale. The result is a tightly constrained chronostratigraphic framework that is applicable from deep to shallow water and is of high accuracy. It is concluded that there is a sedimentation 'pulsebeat' across Southeast Asia, independent of local and regional tectonics, driven by patterns of global climate change. For the Oligocene and Miocene, Antarctic glaciation is the key driver, whereas the Pliocene cycles are mainly driven by the expansion and contraction of Northern Hemisphere glaciers. The new chronostratigraphic framework allows unconformities across Malaysia to be better characterised, and the different classification schemes of seismic "Groups" in Malay and Penyu basins, "Cycles" in offshore Sarawak and "Stages" in offshore western Sabah to be correlated. Also, with a clear understanding of the effect of fluctuating sea levels on the stratigraphy of the region, it is easier to make firm judgments regarding the effect of tectonics. The study also characterises systems tracts from shelf to basin floor using biostatigraphic assemblages, which should help in ground-truthing the architecture of depositional sequences in the region based on seismic. The new framework is proposed as an alternative to the outdated TB scheme of Haq et al. (1988) , widely used to interpret depositional cycles across Sarawak and Sabah. Image 1 • 101 Malaysian exploration wells were studied for Sequence Biostratigraphy. • 41 depositional cycles have been defined from the mid-Oligocene to Pliocene. • Ages are 'fingerprinted' using age-restricted foraminifera, nannofossils and pollen. • Cycles were driven by Antarctic, followed by Arctic ice volume changes. • The study identifies major issues with the 'Haq' and other sea level curves. [ABSTRACT FROM AUTHOR]

In this paper, 5 schemes for reconstructing the sea ice conditions in the Sea of Okhotsk (the SO) during the last 74 kyr are presented. These schemes were constructed based on calculations of the ice rafted debris (IRD) fluxes in 16 sediment cores and the available published mineralogical data (Derkachev et al., 2004). We obtained new data on the orbital-scale changes of the IRD fluxes in the studied area for the last four marine isotopic stages (MIS). As a result, the key areas of sea ice formation and general direction of sea ice drift and, in turn, dominate direction of geostrophic wind in the SO were established for each of the investigated MISs. It allows us to suppose the positions of Siberian High and Aleutian Low during the individual MISs. At that, the sea ice was of predominantly seasonal for studied period, except for the northwestern and western parts of sea, where perennial sea ice fields were preserved over a period of several years during MIS 2. The variations of sea ice conditions attest to a particular type of atmospheric pressure field prevailing over the SO during individual MISs. The secondary sea ice drift directions points out that the predominant atmospheric pressure field during individual MISs were inconstant except the MIS 2. • The atmospheric circulation of the Asia-NW Pacific region in MIS 4–MIS 1 determined the ice conditions of the Sea of Okhotsk. • The alternation of dominant wind regimes over the Sea of Okhotsk is typical for MIS 4, MIS 3, Early MIS 1 and Late MIS 1. • Severe ice conditions and the predominance of strong northern winds over the Sea of Okhotsk are persisted during MIS 2. [ABSTRACT FROM AUTHOR]