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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]

The Mesozoic Dabashan Foreland Basin, a result of the Mianlue Ocean closure, formed through the collision and amalgamation of the South China and North China blocks. As such, it contains an important record of the tectonic processes leading to the formation of the Qinling Orogenic Belt; however, the timing of transition from basin to mountainous terrains remains debated. Geochronological studies indicate continental collision occurred in the mid-Permian to early Triassic, while some paleomagnetic data suggest a Middle to Late Jurassic occurrence time. Utilizing detrital zircon geochronology and trace element data, in this paper, we examine Triassic-Jurassic sediment provenance patterns during the evolution of the Dabashan Foreland Basin. Results show that in the Middle Triassic, the north Yangtze Block received detrital input from the southern margin of the North China Block. In the Late Triassic, significant tectonic inversion occurred, with detrital sources from the southern margin of North China Block, North Qinling, South Qinling, and the north Yangtze Block. During the early and Middle Jurassic, detrital sources gradually shifted to a dominance from South Qinling, indicating a phased southward migration of collisional orogenic belt sources. Combining thermal events, crustal thickness variations, and paleomagnetic data, we propose a novel model explaining oblique compression along the north Yangtze Block during the early Mesozoic. This model suggests that the Dabashan Foreland Basin likely predates the Middle Triassic, and we contend that crustal deformation and lateral shortening during Mesozoic accretionary orogeny between North China Block and South China Block may explain the debate over collision timing. • Provenance analysis dates Dabashan Foreland Basin to the Middle Triassic or earlier. • Frontal orogenic belt migration alters sediment sources to the basin. • Divergent views on collision timing may stem from crustal deformation. [ABSTRACT FROM AUTHOR]

Vertebrate teeth are highly mineralized dermal tissues composed, principally, of bioapatite making them highly resistant to physical and chemical alteration over geologic time scales. This means that the morphology and microstructure of fossil teeth is often preserved, providing diagnostic features for taxonomic classification and enabling inferences about phylogenetic relationships. They also provide abundant information about the feeding ecology of fossil taxa, including diet, feeding behavior, local resource availability, habitat structure, and climate conditions. Tooth shape, tooth wear at different scales, dental chemistry and isotopic composition, as well as ingesta particles aggregated in dental calculus comprise important clues to reconstruct the feeding ecology of a fossil species. This special issue features 21 papers that address the use of dental proxies to infer diet and related ecological habits. Among them, a first paper compares post mortem damages on enamel surfaces with dietary-related tooth wear. Then, nine papers focus on in vivo or in vitro experimentation to test specific hypotheses. Authors address questions about taphonomic processes that may blur dietary or ecological signals, the biotic and abiotic sources of the dental wear, and the calibration of models linking diet composition to dental proxies. Eight papers explore links between dental proxies and ecology and behavior in real world contexts and focus on the study of living mammals in the wild at the individual and population scales. Among those latter studies, three integrate fossil case studies. The remaining papers address questions about niche partitioning, climate effects on local resources and their use, physiology, and the influence of diet on phenotypic selection in extinct species. As such, this special issue will stimulate further work on dental proxies and be of interest to a broad community of palaeoecologists. [ABSTRACT FROM AUTHOR]

Antarctica is one of the most susceptible regions to climate change on Earth. Rising ocean temperatures, glacier melting, and disruptions of marine ecosystems make this polar region a focus of research on ecosystem transformation associated with ongoing climate change. Within the Antarctic ecosystem, diatoms, a key group of phytoplankton at the base of the marine food web, play a crucial role in maintaining marine ecosystem balance and functioning. Conventionally, fossil diatom assemblages have been investigated in marine sediment records to reconstruct paleoenvironmental conditions and understand climate change patterns of Antarctica. Recently, the application of ancient DNA techniques to ocean sediments (sedimentary ancient DNA, sed aDNA) has provided new insights into diatom community responses to environmental change over geological time scales. One benefit of sed aDNA analysis is that this technique can detect fragile diatom species that do not preserve well and are thus difficult to study via traditional microscopy techniques. In this paper, we review the importance of diatoms as indicators of Antarctic paleoenvironmental change, the novel use of diatom sed aDNA to assist Antarctic paleoenvironmental reconstruction, and the challenges and promises of using the sed aDNA approach. We propose that Fragilariopsis cylindrus , an extant polar diatom species, is an ideal model organism to study adaptation patterns of diatoms to changing climate due to its ecological success through time and the availability of whole-genome information for this species. Novel genetic information obtainable from ancient F. cylindrus, as well as other diatoms, will help us to better predict the evolutionary and adaptive dynamics of this important group of primary producers in the climatically vulnerable Antarctic region. • Climate change in Antarctica and the need to study this polar region. • Diatoms in Antarctic ecosystem and their role as paleoenvironmental indicators. • Using the novel technique of sedimentary ancient DNA (sed aDNA) in Antarctica. • Fragilariopsis cylindrus to study adaptation and evolution of diatoms in Antarctica. [ABSTRACT FROM AUTHOR]

In the comment on our paper, Cho and Cheong (2016) and Kim and Ree (2016) make a number of arguments that we did not discuss the Cambrian zircons from our data and have cast doubt on our early Cambrian paleogeographic reconstruction. They also argued that our data do not pass statistical tests between concerned strata for paleogeographic reconstruction. In response to the comment, we show that these arguments are not based on sound geological evidence and conditions that we provided in our paper. [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]

Abstract The Aoerban region of central Inner Mongolia, China is an important early Miocene fossil site that contains a diverse mammalian record unrivaled by other Asian sites of similar age. In this paper, we present lithostratigraphic, biostratigraphic, and magnetostratigraphic data from Aoerban Formation to better understand faunal changes between the Xiejian and Shanwangian Chinese Land Mammal ages. With new biochronological constraints, magnetochrons in the Aoerban Formation can be correlated to C6An.2n to C5Cr with an age range of 20.71–16.72 Ma of the Astronomically Tuned Neogene Timescale (ATNTS2012). The strata of the Aoerban region contain a number of important mammalian First Appearance Data, including several morphotypes of deer (Cervidae), horses (Anchitherium), pika (Alloptox), cricetid rodents (Megacricetodon), and possibly the local earliest record of gomphotheres (i.e., the Proboscidea event). Although the ranges for most of these taxa are still poorly known, some of them, alone or in combination, are useful in defining the base the Shanwangian Land Mammal Age. Within this finely calibrated chronologic framework, the faunas of the Aoerban region are important for better understanding mammalian evolution, biogeography, and paleoenvironment. Highlights • The Early Miocene Aoerban site in Inner Mongolia contains a rich vertebrate fauna • A biostratigraphy for each species details their sequential occurrences in strata • A high-resolution magnetostratigraphy permits correlation to Geologic Time Scale. • This chronologic framework helps to integrate fossils and paleomagnetics • Aoerban records first appearances of deers and other mammals in Asia. [ABSTRACT FROM AUTHOR]

The megafauna extinction in South America was one of the most profound events, with the loss of 50 genera (~ 83%). Three orders disappeared (Notoungulata, Proboscidea, Litopterna), as did all large xenarthrans, but how this fits into global extinction is uncertain, mainly due to the lack of chronological resolution. In recent years there has been an increase in the number of radiocarbon dating at archeological and paleontological sites, but this information varies greatly from area to area in South America, and few data can be considered to constitute a taxon-date. The timing of the late Pleistocene extinction in the Pampas is poorly established. Most taxa only appear in the biostratigraphic context and many reported 14 C dates do not meet rigorous criteria for accepting dates, including reports suggesting survival of megafauna into the Holocene. In the present paper, we evaluate the published radiocarbon dates in the pampas and present 20 new radiocarbon dates for paleontological sites in order to establish a more accurate “extinction window” for the key taxa. These new dates are sufficiently robust to assess correspondences among last-appearance records of megafauna, first-appearance records of humans, and the Younger Dryas to Holocene climatic transition in the Argentine Pampas. These results highlight the need for greater effort in taxa selection for dating. [ABSTRACT FROM AUTHOR]

The present paper documents and discusses a new Albian–early Cenomanian carbon isotope (δ 13 C carb and δ 13 C org ) curve from the subequatorial Eastern Pacific in Peru. Chemostratigraphic evidences for the expression of the OAE1b set and for OAE1c and OAE1d are presented. This dataset is relevant inasmuch as previous work is strongly biased towards study sites in North America (Western Interior Basin), in Europe (Tethys) and the Pacific realm. A comparison of the carbon isotope stratigraphy obtained in Peru with published sections from the Central and Western Pacific, the Western Atlantic and Northern and Western Tethys reveals an overall good agreement supporting the global nature of the isotope patterns described here. The δ 13 C from Peru record is constrained by biostratigraphic evidence and 87 Sr/ 86 Sr isotope stratigraphy using well-preserved oyster shells. Furthermore, we document the development of a heterozoan epeiric–neritic mixed carbonate–siliciclastic ramp in the Western Platform of Peru and its corresponding sedimentary facies associations. This dataset was used to elucidate the complex interplay of climatic changes, nutrient supply, and platform drowning, leading to the following conclusions: (i) an upper Aptian–lower Albian major change from siliciclastic-dominated to carbonate sedimentation coincided with the impact of the Kilian Level, (ii) a lower Albian incipient platform drowning linked to the impact of the Paquier Level, (iii) A lower middle Albian major demise of neritic carbonate production that coincides with the Leenhardt Level, followed by middle Albian condensed sedimentation that reports prominent negative values in δ 13 C carb prior to the onset of OAE1c and (iv) finally, renewed carbonate ramp production during the upper Albian–lower Cenomanian. The data shown here represent the foundation for future work documenting the mid-Cretaceous of Peru and its implications for the palaeoceanography of the SE subequatorial Pacific. [ABSTRACT FROM AUTHOR]

A new sauropod-dominanted dinosaur fauna, including several new species of sauropods and stegosaurs, was recently excavated from the Lower Shaximiao Formation in Yunyang, northeastern Chongqing, southwestern China. Although this dinosaur fauna could possibly provide significant clues for a better understanding of the basal sauropod's evolution and diversification of basal sauropods in the Jurassic, many aspects of this fauna are not well defined constrained in terms of detailed stratigraphy, geochronology, and comparison with similar faunas in other regions of the Sichuan Basin. This paper reports on the petrological features of this locality, using Scanning Electron Microscopy (SEM) and Energy Dispersive Spectrometry (EDS), with laser ablation-multi-collector-inductively coupled plasma-mass spectrometry (LA-ICP-MS) zircon U-Pb geochronology for a tuffaceous siltstone layer beneath the dinosaur fossil-bearing layers from the fossil site. The SEM and XRD results show a typical tuffaceous mineral composition of this layer. Zircon U-Pb data yielded a weighted average age of 166.0 ± 1.5 Ma, indicating a maximum burial age for this dinosaur fauna. This fauna is chronologically comparable with the Shunosaurus-Omeisaurus Fauna, which is primarily found in the central Sichuan Basin. • 166.0 ± 1.5 Ma as the maximum burial age for dinosaur fauna in Chongqing, SW China. • Precise age constraints on newly discovered dinosaur in Lower Shaximiao Formation. • Basal sauropods in Sichuan Basin are younger than biostratigraphic ages. • Providing age constraints on the radiation of basal sauropods in Jurassic. [ABSTRACT FROM AUTHOR]

Abstract: The Jurassic–Cretaceous (J–K) boundary is one of the most problematic points on the geological timescale. The boundary is not defined by a Global Stratotype Section and Point (GSSP) because of the absence of well-defined (by significant faunal turnover), widely correlatable biostratigraphic levels to fix the base of the Berriasian. A distinct earliest Berriasian positive carbon isotope excursion is identified in the Boreal marine carbonate (belemnites) carbon records from the Maurynya River (Northern Urals) and the Nordvik Peninsula (northern East Siberia). The excursion is found within the top part of the upper Volgian Craspedites taimyrensis ammonite Zone, slightly above the J–K boundary, which was established by palaeomagnetic data. Because a significant positive δ13C shift was also observed immediately above the J–K boundary in the Tethyan Guppen-Heuberge pelagic-carbonate section (Switzerland), this positive carbon isotope event can be regarded as a useful marker for a Panboreal and Boreal–Tethyan correlation of J–K boundary beds. This δ13C excursion is interpreted as a record of increased rates of organic carbon burial. The δ13C data obtained previously for the upper Volgian and Ryazanian in different Boreal regions are also analysed in this paper. Other well-documented carbon isotope excursions with less global significance allow the creation of a composite carbon-isotope curve for Boreal regions that characterises the upper Volgian and Ryazanian in detail. [Copyright &y& Elsevier]

Abstract: The Pliocene (5.3–2.6Ma) of Tibet witnessed the drying of the northern Tibetan Plateau and the approach to the Pleistocene Ice Age within the background of intensifying Indian and East Asian monsoons. Yet little is known about Pliocene mammals living on the high Tibetan Plateau despite the fact that fossil mammals elsewhere constitute an important knowledge base for terrestrial environments. The late Miocene to Pleistocene Zanda Basin at the northern foothills of the Himalayas affords a welcome opportunity to evaluate the biological response to environmental change at high elevations. Abundant, well-preserved fossil mammals and fish from an 800-m continuous section of fine- to coarse-grained sediments thus open a rare window into a past biological world. For example, the discovery of an ancestral wooly rhino from Zanda Basin that was the precursor of its late Pleistocene megafaunal descendants leads to our “out-of Tibet” hypothesis, suggesting that the high Tibetan Plateau was a Pliocene cradle for Ice Age cold adaptations. In this paper, we document in detail the mammalian biostratigraphy, chronology, and paleozoogeography based on Zanda Basin fossil mammals. Our high-resolution biostratigraphy and biochronology offer for the first time independent constraints that both support and modify recent magnetostratigraphic correlations. Using characteristic Pliocene and Pleistocene mammals, particularly the small mammal assemblages in the lower part of the section and monodactylid Equus from the upper section, we propose a correlation to C1n to C3An.1r, with an age range of ~400Ka to 6.4Ma. Within the 800-m Zanda section, the lower 0–150m is of latest Miocene age, spanning 6.4–5.3Ma. Sparsely fossiliferous, the lower section has produced five taxa so far: Ochotona, Panthera, Qurliqnoria, Palaeotragus, and Hipparion—all are consistent with a late Miocene age. The middle 150–620m section spans the entire Pliocene. This section is by far the most fossiliferous, including such typical Pliocene small mammals as Prosiphneus, Mimomys, Apodemus, and Trischizolagus, as well as large mammals such as Coelodonta thibetana, Hipparion zandaense, Chasmaporthetes, Nyctereutes, Meles, Antilospira, and others. In the upper 620–800m section the fossils are rare, but do include characteristic Pleistocene taxa such as Equus. Zoogeographically Zanda Basin mammals are a mixture from two major sources. Taxa such as Mimomys, Prosiphneus, Trischizolagus, Chasmaporthetes, Nyctereutes, Meles, and Xenocyon are commonly found in north China or east Asia. In contrast, several forms, such as unique species of pikas (Ochotona), squirrels (Aepyosciurus), and ancestral Tibetan antelope (Qurliqnoria), seem to belong to an indigenous Tibetan fauna evolved within the plateau. A lack of shared taxa with the Oriental Realm suggests a formidable barrier by the Himalayas despite a short distance (~100km) between Zanda Basin and the Indian subcontinent. [Copyright &y& Elsevier]

Abstract: This paper documents the occurrence of the Little Ice Age (LIA) in the El Azufre and El Peñón glaciers at 35°S and in the Las Choicas and Las Damas glaciers at 34°55′S in the headwaters of the Rio Grande basin in the Central Andes of Argentina. Moraine morphology, stratigraphic relationships, radiocarbon ages obtained from peat on these glacial deposits and the proximity to the active glaciers enabled us to reconstruct the LIA advance in this area. The LIA maximum advance occurred between cal. yr 1550 and 1720 AD, and a readvance occurred around cal. yr 1830 AD. In addition, glacier fluctuations of the Las Vacas and Güssfeltd glaciers (33°S) and El Peñón and El Azufre glaciers were documented from the end of the 19th century to the present based on historical and aerial photographs, and satellite images. The glaciers showed a marked retreat during 1894–2007. Minor readvances occurred in the 1980s and 1990s, which could be related with strong warm ENSO events during these decades. Our results are consistent with observations made by other authors in the region. [Copyright &y& Elsevier]

Interactions between human societies and the environment that they inhabit have been a controversial topic in archaeology for at least the past fifty years. Currently, modern theoretical approaches take this subject as a key issue in their research agenda. This paper presents a review of the main outcomes of several archaeological and multidisciplinary South American projects related to this theme. The case-studies discussed here are all located within arid settings, and can be grouped into three broad geographic areas: Puna (or Altiplano) of northwestern Argentina, Cuyo (west-central Argentina), and southern Patagonia. These regions cover a wide latitudinal range extending from 22° to 52° S. They were selected for comparison due to environmental similarities, and a common record of past climate impacts mainly related to the Medieval Climatic Anomaly (MCA) and the Little Ice Age (LIA). Although the impacts of these climatic changes were locally heterogeneous in their intensity and the quality of the available information is regionally variable, they provide a base-line for comparison and supra-regional integration. The integration of archaeological and palaeoenvironmental data on this broad supra-regional spatial scale allows us to identify interesting historical trajectories associated with particular time periods. As an example, there are some spatial rearrangements of large populations during the MCA, in the three areas. Additionally, there are variable patterns in the changes associated with the different social contexts that impose specific demographic and economic constraints. Finally, this study sets the basis for new questions and provides a guide to the methodological and theoretical issues that we need to address in order to answer them. [Copyright &y& Elsevier]

Abstract: The aim of this paper is to document the evolution of glaciers in the tropical Andes (between 10°N and 16°S) for the last millennium, based on moraines dated by lichenometry and radiocarbon, lake sediment records and historical documents. Viewed collectively, several glacial advances occurred synchronously. The first advance is dated around AD 1200–1350. The maximum glacial extent (MGE), defined as the furthest down-valley extent recorded synchronously by the majority of glaciers, occurred around 1630–1680 in Bolivia and Peru (the outer tropics) and around AD 1730 in Ecuador, Colombia and Venezuela (the inner tropics). Subsequently, during the 18th and 19th centuries, glaciers retreated continuously with only minor synchronous readvances. In the outer tropics, minor glacial advances occurred around 1730, 1760, 1800, 1850, and 1870. In the inner tropics, synchronous minor advances occurred around 1760, 1820 and 1880. Between the MGE and the early 20th century, glaciers lost about 30% of their total length. The retreat was slow between the 17th and 18th centuries but then became more marked. Use of the accumulation area ratio (AAR) method or historical observations in the different cordilleras revealed an increase in the equilibrium line altitude (ELA) of about 300 m from the MGE onward. Palaeoclimatic hypotheses, based on glaciological models run in different countries, suggest a cool and humid period in the 16–18th centuries followed by a colder and drier period in the 19th century. The reduction of glaciers observed from the middle of the 19th century is due to increasingly warmer conditions than before. Here, quantitative estimates are proposed to explain the evolution of the glaciers. In Venezuela, results indicate for the period 1250–1820 that mean air temperatures were 3.2±1.4 °C cooler and precipitation was about 22% higher than at present. In Ecuador, temperatures of between 0.8° and 1.1 °C lower than today, and between 25% and 35% higher accumulation than today, appear to have occurred in the 18th century, followed by a short drier but colder period at the beginning of the 19th century. In Bolivia, the MGE could be a consequence of a decrease in temperature of 1.1 to 1.2 °C, and a 20 to 30% increase in accumulation or an increase in cloudiness of about 1–2/10. We discuss not only external climatic forcing but also the coincidence between glacier expansion and a decrease in solar irradiance. Dating uncertainties, however, have made the role of volcanism in glacier fluctuations impossible to determine. Finally, we discuss the relationships between ENSO and glacier fluctuations in recent centuries, which do not match directly with current knowledge of modern teleconnections between tropical Pacific SSTs and variations in glacier mass balance. [Copyright &y& Elsevier]

Abstract: This paper presents an updated, extensive review of glacier fluctuations during the past 1000years in the extratropical Andes of South America between ca. 17° and 55°S. Given the variety of environmental conditions and evidence available for glacier fluctuations across this wide latitudinal range, regional accounts are given for the Desert Andes (∼17°–31°S), the Andes of central Chile and Argentina (31°–36°S), and the North (36°–45°S) and South (45°–55°S) Patagonian Andes. The techniques, dating limitations, and interpretations of the glacier records along this transect are also discussed. Information on glacier fluctuations in the Desert Andes is limited to the 20th century. Documentation on past glacier variations is more abundant in the Central Chilean-Argentinean Andes, but the number of chronologies dealing with glacier fluctuations prior to the 1900s is also limited. Most records indicate that glaciers were generally more extensive prior to the 20th century, with dates of maximum expansion ranging from the 16th to the 19th centuries. The number and extent of glaciers increase significantly in the Patagonian region, where the evidence available for dating glacier variations during the past centuries is more abundant and the dating control for glacier events is generally better than in the northern parts of the study area. For some Patagonian glaciers, maximum Little Ice Age (LIA) or post-LIA advances have been precisely dated by dendro-geomorphological determinations or in situ measurements. However, for most sites, the evidence available is still preliminary and there is considerable variability in the extent and timing of events related to the maximum LIA expansion identified in most areas between the 16th and 19th centuries. Evidence is starting to appear at a growing number of sites for glacier advances during the first half of the past millennium. These events were generally less extensive than the LIA maximum pulses. Despite the occurrence of several post-LIA readvances over the past 100–110years, most areas in the Andes of extratropical South America have experienced a general pattern of glacier recession and significant ice mass losses. The differences in the glacier histories observed at local and regional scales probably reflect the inherent limitations associated with the glacier records and/or the dating techniques used in each case together with the varying dominance of precipitation, temperature and other climatic and non-climatic factors on glacier mass balance and glacier dynamics. These differences indicate that the late Holocene glacier history of southern South America is more complex than commonly assumed. The evidence discussed in this study highlights not only the immense potential for glaciological studies of this region but also a significant need for an increased number of detailed, well-dated records of glacier fluctuations. [Copyright &y& Elsevier]

Abstract: Major ecological changes related to anthropogenic activities begin on islands with initial human settlement. Key factors to understanding insular Holocene ecological changes are the arrival dates of both humans and alien species to the islands. In this context, finely stratified fossil sites are powerful tools to study the chronology and causes of these changes. Previous work, based on conventional 14C ages of land snails coming from the finely stratified site Cueva del Llano at Fuerteventura (Canary Islands, eastern Atlantic Ocean), indicates that one of the major ecological changes that took place in this archipelago–the arrival of house mouse Mus musculus–occurred around 7000 yrs ago, thus before the first arrival of humans to the islands. To extend these studies, we obtained 14C ages by accelerator mass spectrometer (AMS) directly on bone collagen from selected bones of rodents: lava mouse Malpaisomys insularis and house mouse, from seven sites: Cueva del Llano, Cueva de Villaverde and Malpaís de La Arena I & II (Fuerteventura), El Bebedero and Jameo de la Puerta Falsa (Lanzarote), and Barranco de la Baranda (La Palma). The new ages derived from the upper levels of Cueva del Llano (CLL 9.1–9.2) indicate a very young age for these materials, between 1667–1949 and 1261–1391 cal AD. These results support a more recent and very different chronology for the Holocene ecological changes that occurred on these islands compared to previous studies. Explanations for the stratigraphically anomalous age shown in previous papers are put forward. On the other hand, the available 14C ages indicate that the house mouse arrived on the eastern Canary Islands some time between 756 cal BC–313 cal AD and, probably from there, spread to the other islands before European contact. [Copyright &y& Elsevier]

It has been demonstrated that the sedimentary deposits of Eocene succession in Bohai Bay Basin in China responded to astronomically forced climate changes. Several sections have been evaluated for cyclostratigraphy and many astronomical time scales (ATSs) have been constructed in Paleogene Bohai Bay Basin. However, the calibrations of age model and the constructed ATSs failed to reach an agreement and many of them relied on totally different orbital interpretations within the same section/borehole. In this work, we generated a new ATS for the middle Eocene lacustrine strata of middle to lower Member 3 (Es3m-l) and upper Member 4 (Es4u) of Shahejie Formation in Bohai Bay Basin. In this research, high resolution natural gamma-ray (GR) data were used for the cyclostratigraphy analysis of Es3m-l and Es4u Members of Well Fanye-1. We filtered ~11.11 m cycles of t Es3m-l and ~9.26 m cycles of Es4u which were directly correlated to the short eccentricity cycles (~100-kyr) of La2004 solution. The geomagnetic polarity ages of C18r/C19n, C19n/C19r and C19r/C20n in Geological Time Scale 2020 were adopted as age markers for the tuning in this study. This astrochronology provided astronomical time scale (ATS) in the range of 39.268 ± 0.050 Ma to 43.621 ± 0.050 Ma in Es3m-l and Es4u Member. The astrochronology of Well Fanye-1 of the same interval had been studied before. However, the ATS built in this paper used correlation coefficient (COCO) analysis and average spectral misfit (ASM) approach to provide quantitative measurement for fitting the observed sedimentary cycles to astronomical periods and given a range of plausible sedimentation rate. In this research, a sedimentary noise model was applied for the detection of high-resolution lake-level variations controlled by orbital forcing. The lake-level variations generated from the sedimentary noise model were supported by previous sequence stratigraphic interpretations. Variable sedimentation could be affected by lake-level changes which have been demonstrated by the evolutionary correlation coefficient analysis of GR series. In addition, from the ATS and thin section observations, it was concluded that carbonate-clay laminae in lacustrine shale were generated annually. Seasonal carbonate-clay laminated shale formations are controlled by orbital scale variability of monsoon and are always developed in a relatively high eccentricity amplitude under deep water environment conditions. Finally, the lake-level rise at ~40.500 Ma to ~40.050 Ma was demonstrated to be the response to Middle Eocene Climate Optimal (MECO) event in lacustrine records. • We provide a new astrochronology for the Es3m-l andEs4u in Well Fanye-1 of middle Eocene in Bohai Bay Basin. • Comparisons of the ATSs of the same borehole and the same interval between this study and previous study have been made. • Sedimentary noise modeling of lacustrine strata is used for paleolake level reconstruction. • Astronomical forcing had a significant impact on carbonate-clay laminated shales development. [ABSTRACT FROM AUTHOR]