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Sharks are virtually absent from coastal Antarctica since the Late Eocene glaciations, but this group exhibited a notable austral diversity during the Cretaceous and Paleogene. Several species have already been described from the Aptian-Eocene successions of the Larsen Basin exposed in the James Ross Island area (northern Antarctic Peninsula) and the predominantly deep-water Hexanchiformes have a record that, although still rare, has been continually increased. Four species of this group are currently known from that basin: Notidanodon pectinatus, Xampylodon dentatus, Rolfodon thompsoni, and Rolfodon tatere. Such records are especially concentrated in the Gamma Member of the Snow Hill Island Formation (or Herbert Sound Member of Santa Marta Formation), on James Ross Island. Here we described four teeth assigned to X. dentatus and one identified as R. tatere from upper Campanian sections of James Ross Island, highlighting the nomenclatural changes that led to the definition of Xampylodon and Rolfodon. Some specimens of X. dentatus presented here are considerably more complete or represent teeth of different positions than most previous records. The material assigned to R. tatere represents the oldest record of this species in the world, extending its time range by more than 10 million years. [ABSTRACT FROM AUTHOR]

Only at Cape Surprise, central Transantarctic Mountains, is there exposed stratigraphic evidence for major offset along the range front, which marks a major boundary in Antarctica. Several faults parallel to the range front have been identified in the Devonian to Triassic Gondwana strata in the hinterland. Analysis of the stratigraphy based on field observations and the United States Geological Survey (USGS) aerial photographs, in conjunction with USGS topographic sheets and satellite-derived elevation measurements, suggests an array of faults with varying orientations and displacements. Fault offsets range up to an estimated 850 metres. No additional range-parallel faults have been identified and no clear pattern of faulting is evident in the hinterland of the frontal escarpment. Faulting may date from the time of slow uplift during the Cretaceous as well as the more rapid Cenozoic uplift of the range. Only a few faults in the hinterland can be allied with the fontal fault system. Cenozoic uplift and associated denudation was accompanied by glaciation of Antarctica, which is documented by Sirius Group strata. These deposits, which pre-date today's polar landscape, are older than mid Miocene, and in part may date from the earliest stages of warm-based glaciation in the early Oligocene. [ABSTRACT FROM AUTHOR]

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

Evidence of glaciation is recognized in Earth's history from 2.9 Ga to the present, providing important information regarding the climatic, sedimentary, and tectonic evolution of our planet. Glaciers are highly effective agents of erosion that generate and transport large amounts of sediments for 100ʹs of kilometres. Therefore, detrital zircon geochronology of glaciogenic sedimentary rocks can elucidate the provenance and evolution of the sedimentary record through time. In this study, we investigate the Paleoproterozoic Glaciation Event which is hypothesized to be the oldest global glaciation in Earth's history (2.4 to 2.2 Ga). We identify distinct sedimentary provenance patterns between the Archaean supercratons Sclavia and Superia, which, comprised most of the extant Archean crust. The detrital zircon of Sclavia exhibit increasing dissimilarity through time whereas the detrital zircon ages of Superia show consistent age peaks through time. Coupled with the absence of glacial deposits and predominance of marine sedimentary successions within Sclavia, the detrital zircon provenance likely indicates limited subaerial exposure of continental crust in Sclavia with glaciers narrow mountain belts producing no diamictites. This model resolves previous issues related to hypotheses proposing high-obliquity low latitude glaciation of Superia as the only explanation available. [ABSTRACT FROM AUTHOR]

Ice coverage not only affects the climate and landscape of geographical regions but has impacted species composition, the fragmentation and isolation of populations, and the colonisation routes of species post-glaciation. Major advancements in generating genetic data and applying sophisticated analyses to accurately model the demographic and colonisation history of animal and plant species has allowed evolutionary biologists novel insights. Meanwhile, physical geographers have made major advancements in reconstructing glacial history. However, the information flow between the geographic and evolutionary fields on this topic remains limited; consequently, evolutionary studies on contemporary biodiversity and species colonisation tend to be vague about the role of glacial history, while evolutionary and biodiversity information is rarely leveraged when discussing historical glaciation. In this review, we bring together current knowledge on the changing patterns of ice coverage in the British Isles from the maximum extent of the British-Irish ice sheet (BIIS) ca. 27 ka through to the end of large-scale ice coverage at the start of the Holocene period ca. 11.5 ka. We do so to then highlight how glaciation affected species composition during this time period and the subsequent colonisation of temperate flora and fauna and the patterns of genetic variation seen in them. [ABSTRACT FROM AUTHOR]

Abstract Natural analogues are systems that have evolved over geological timescales with features similar to one or several components of a deep geological repository (DGR). Natural analogues complement short-duration laboratory studies since they are existing reflections of many long-term processes that might affect the performance of a repository. Mathematical models are often used for the post-closure safety assessment of a DGR. Confidence in the models’ predictions is enhanced when the models successfully simulate the past evolution of a natural analogue. This paper summarizes the Canadian Nuclear Safety Commission’s (CNSC’s) recent research on natural analogues to inform on (1) glacial erosion, (2) engineered barrier system, and (3) uranium reactive transport in the context of DGRs for radioactive wastes. Glaciation and its erosion are prominent factors impacting the performance of future DGRs at high latitudes in the northern hemisphere. The authors have reviewed the field data from the Greenland Analogue Project, developed a conceptual and mathematical model for the simulation of the thermal conditions within the Greenland ice sheet, as well as the thermal-hydraulic conditions at its base and the ice sheet velocity, and eventually estimated the erosion rate at the site.The Cigar Lake Analogue demonstrates the long-term radionuclide containment capability of the illite clay zone enveloping the ore body, serving as an analogy to the engineered clay barriers. The CNSC and University of Ottawa analyzed 129I in the Cigar Lake core samples, and modeled and correlated the diffusion-dominated transport of radionuclides over the geological evolution of the Cigar Lake deposit. The results provide information on the mobility of fission products and significant radionuclides in conditions analogous to the source, engineered barriers, and near-field host rock of a DGR.The reactive transport and geochemistry of the Kiggavik-Andrew Lake uranium deposit mineralization and remobilization was another natural uranium deposit analogue studied by the CNSC. A reactive transport model was established according to the conceptualized geochemical processes and run under specified boundary and initial conditions to validate the geochemical processes. The geometry, timing, geochemistry, and fluid composition were used as model constraints. [ABSTRACT FROM AUTHOR]

Vertically accreted, cyclic tidal rhythmites—laminated, fine-grained sandstones, siltstones and mudstones—occur in the late Cryogenian glaciogenic Elatina Formation (ca 635 Ma) and early Cryogenian Sturt Formation (ca 660 Ma) in the South Flinders Ranges region of the Adelaide Rift Complex within the Adelaide Superbasin, and in Cryogenian strata from Nicholson 2 drill hole in the eastern Officer Basin, South Australia. The rhythmites provide insights into Cryogenian littoral environments. The Elatina rhythmite was deposited during an interstadial and the Sturt rhythmite during early glacial advance, whereas the Nicholson 2 rhythmite is assigned to interglacial beds. The resultant raised sea levels and drowned valleys provided the tidal inlets, ebb-tidal deltas, estuaries and fjords favouring rhythmite deposition. The rhythmites display semidiurnal and diurnal (lunar day) tidal laminae grouped in fortnightly neap–spring cycles and record the semiannual tide. Periods of 26.2 ± 0.9 neap–spring cycles displayed by the Elatina rhythmite and ∼27 neap–spring cycles by the Nicholson 2 rhythmite mark the non-tidal annual variation of sea level, which results from seasonal surface winds and changes in atmospheric pressure and temperature acting on the waters of marine shelves and marginal seas. The strong annual signals and absence of dropstones in the Elatina and Nicholson 2 rhythmites indicate that respective marine shelves and marginal seas were ice-free during rhythmite deposition. The Sturt rhythmite, by contrast, shows a weak annual period of ∼27 neap–spring cycles and contains dropstones and till pellets, indicating that the adjacent marine shelf and sea were largely ice-covered. Paleotidal data for the Elatina rhythmite have illuminated Earth's late Cryogenian paleorotation and the Moon's orbit, and paleomagnetic studies of the Elatina rhythmite indicated a low paleolatitude for late Cryogenian glaciation. Contrary to recent modelling by others, strong tides existed at shallow-water continental margins during Cryogenian glaciations. Cyclic tidal rhythmites are associated with early and late Cryogenian (ca 660 and ca 635 Ma) glaciogenic successions and interglacial beds in South Australia. Rhythmite deposition occurred when raised sea levels provided the coastal environments favouring rhythmite deposition. The rhythmites display semidiurnal and diurnal tidal laminae grouped in fortnightly cycles, and record the semiannual tide and the non-tidal annual variation of sea level. Strong tides existed at shallow-water continental margins during early and late Cryogenian low-latitude glaciations and the interglacial interval. [ABSTRACT FROM AUTHOR]

Throughout the Flinders Ranges of South Australia, the red bed Brachina sequence comprises the lower of two regressive, coarsening-upward successions that together constitute the Ediacaran-aged Wilpena Group. Detailed examination of the Brachina sequence has identified evidence of ice-rafting, supporting the contention that frigid climatic conditions continued well after cessation of the Marinoan Glaciation, as well as features postulated to be harbingers of the macroscopic metazoans that occur in abundance higher in the local stratigraphy. Although tuffaceous and lying stratigraphically between deposits of the Marinoan Glaciation and the Acraman Impact/Gaskiers Glaciation, no absolute age dates exist for the sequence. However, through correlation to the global carbon isotope profile, the timespan of Brachina sequence deposition can be constrained to between 635 and 586 Ma, when the regression climaxed with terrestrial deposition upon a local disconformity. The tuffaceous input is timed to have begun at 620 Ma, essentially coincident with initial formation of the passive volcanic continental margin of southeastern Australia and initiation of both the Volyn Large Igneous Province and activity within the Central Iapetus Magmatic Province, all components marking the demise of Rodinia and initial amalgamation of Gondwana. Correlation to the global carbon isotope profile dates the early Ediacaran Brachina sequence of the Flinders Ranges to between 635 and 586 Ma. The ABC Range Quartzite in the central Flinders Ranges is derived from, and hence younger than, the deltaic ABC Range Quartzite in the southwestern Flinders Ranges. Several volcanic outpourings across the Ediacaran globe during the final breakup of Rodinia and initial assembly of Gondwana, including that associated with the development of the eastern Australian passive margin, produced an abundance of atmospheric ash that settled during and beyond deposition of the Brachina sequence. [ABSTRACT FROM AUTHOR]

Highly diverse and well preserved organic-walled phytoplankton were recorded from the Darriwilian–early Katian interval of the Borenshult-1 drillcore. We identified 154 species in 53 genera, and three assemblages were distinguished; Assemblage A of a late Darriwilian age, Assemblage B of a Sandbian age (further subdivided into sub-assemblages B1 and B2), and Assemblage C dated as Katian. Taxa with "Silurian affinities" with previous first appearance datum in the early Silurian, Hirnantian, such as Metaleiofusa and Visbysphaera, are here recorded from the late Darriwilian and Sandbian respectively. These occurrences question the relationship between the appearance of pioneering phytoplankton morphotypes and the Hirnantian glaciation. Other taxa with no pre-Silurian records such as Visbysphaera pirifera subsp. minor, Petaloferidium cazurrum and Dorsennidium cf. D. estrellitae are here present in the Sandbian, where bentonite beds are intercalated. The diversity curve of acritarchs shows similarities with those proposed for the Darriwilian-Katian of Baltica with main differences in the interval with bentonite beds representing an intense volcanic activity. The species Metaleiofusa arcuata Wall is here emended and a new combination is proposed: Petaloferidium cazurrum (Cramer) comb. nov. The genus Fankea is recorded for the first time from Swedish strata, suggesting a dominant high- to middle latitudinal distribution instead of a Perigondwanan distribution. We contend that the location of paleo-southern Sweden contributed to the great diversity seen, since a middle-low latitude provided a suitable habitat with warm, shallow water, rich in nutrients. [ABSTRACT FROM AUTHOR]

Plant adaptations to environmental and climatic changes in Pangaean intramontane basins are poorly understood. Here, we document a previously unknown primitive gymnosperm species, Lesleya ceriacoi sp. nov., from the Douro Carboniferous Basin (DCB; lower Gzhelian, Upper Pennsylvanian; NW Portugal) of the Variscan Iberian Massif (Iberia). This new species is described from a 303 million-years-old fossil rediscovered at the U.Porto's Herbarium PO, stored at the Museu de História Natural e da Ciência da Universidade do Porto (MHNC-UP; Portugal). L. ceriacoi sp. nov. displays an exquisite leaf shape with morphological traits adapted to specific ecological conditions of the DCB. These leaf morphological traits comprise toothed and dissected margins, which represent specialised adaptations to drier (xerophytic) conditions of the DCB during the Gzhelian (ca. 304–299 Ma), at the end of the Late Pennsylvanian. The xeromorphic traits of the new species represent an evolutionary novelty for the Pennsylvanian Euramerican dry-climate adapted floras, and are evidence of evolutionary adaptation to environmental and climatic change in intramontane basins like DCB within central tropical Pangaea. Such an adaptation occurred during an interval of wet to dry climate transition after the end of one late Palaeozoic Gondwana Ice Age (glaciation) in Gzhelian time. [ABSTRACT FROM AUTHOR]

A unique 10–140 cm thick veneer of greensand and glauconite-rich deposits (10–80 wt% glauconite) presently sits atop central Chatham Rise (CR) in water depths of 200-500 m. The glauconite is dominated by chemically mature, polished ovoidal and lobate pellets, with a 10–12 Å phyllosilicate structure and K-Ar ages of 7–5 Ma, indicating that the glauconite pellets are predominantly allogenic (i.e. derived/reworked) grains, and not of in situ authigenic origin. Glauconite possibly evolved from seafloor alteration of detrital and/or volcanogenic smectitic clays, likely concentrated within organic-rich faecal pellets under unique paleoceanographic conditions (nutrient cycling, upwelling, carbon isotope gradients) within the latest Miocene Subtropical Front. The distribution of glauconite abundance suggests a 'glauconite factory' existed at this time about Reserve Bank on western central CR. The pellets were dispersed eastwards along the crest by intensified bottom currents within the dynamic Subtropical Frontal zone, perhaps during the numerous glacial periods of lowered sea level throughout the Plio-Quaternary. The bioturbated greensand veneer, and its mix of other reworked Neogene and Quaternary skeletal, phosphatic and siliciclastic components, rest unconformably on mainly Early Oligocene chalks, forming a highly condensed, relict/palimpsest deposit that alone embodies the last up to 30 My of sedimentation history atop central CR. [ABSTRACT FROM AUTHOR]

Late Early Pleistocene vertebrate assemblages in the Mediterranean area have sparked the interest of the scientific community in the last two decades mainly thanks to the discovery of fossils and/or stone tools testifying to the presence of early Homo. However, our knowledge of most of these assemblages is biased by the lack of well-constrained chronological data, especially for those close to or related to the Jaramillo magnetostratigraphic subchron (ca. 1.0 Ma). As a matter of fact, the available European palaeontological assemblages chronologically close to the Jaramillo interval are overall scarce, especially for the period prior to the so-called '0.9 Ma event'. This long and cold glacial period was characterised by profound changes in ecosystems and important faunal turnover in Europe, including the replacement of most Villafranchian species by typical Galerian ones. Here, we report on the carnivoran remains from Collecurti (central Italy), that is, one of the few available Jaramillo-dated assemblages in Europe. The Collecurti sample includes the species Canis (Xenocyon) lycaonoides, Canis mosbachensis, and Ursus deningeri and is here described in detail for the first time and compared with those from similar-aged European sites. [ABSTRACT FROM AUTHOR]

The fossil record of Leiopelma frogs in New Zealand is patchy, with remains previously reported only from the early Miocene (16–19 Mya) and late Quaternary (past 20 Ka). Here we describe Leiopelma bishopi n. sp. from the late Pliocene (3.7–2.4 Ma) of the eastern South Island. The subsequent extinction of frogs in this region is likely due to increased aridity following uplift of the Southern Alps and cooling associated with the Pleistocene Ice Ages. Discoveries from this unique Pliocene terrestrial fossil locality provide new and significant insights into how the dynamic climatic and geological history of Zealandia has shaped the evolution of its recent biota, especially for groups with a poor pre-Quaternary fossil record. LSID: Abbreviations: SVL: snout-vent length; NMNZ: Museum of New Zealand Te Papa Tongarewa, Wellington, New Zealand; WO: Waitomo Caves Museum, Waitomo, New Zealand [ABSTRACT FROM AUTHOR]

After the Elatina glaciation of Snowball Earth, at least four distinct glacial advances and sea-level retreats punctuated Ediacaran time: Gaskiers glaciation (580 Ma), Fauquier glaciation (571 Ma), Bou-Azzer glaciation (566 Ma) and Hankalchough glaciation (551 Ma). Tillites or diamictites are commonly controversial, but periglacial paleosols with distinctive physical structure and degree of chemical weathering offer supporting evidence of glaciation and sea-level change useful for stratigraphic correlation. This paper reviews glacial advances of the Ediacaran stratotype and other sequences, and also reveals the value of paleosols and chemical index of alteration to understand the upper Squantum and Brookline members of the Roxbury Conglomerate near Boston, Massachusetts. The Boston Bay ice wedges are periglacial paleosols, and evidence of maritime glacial climate like that of modern coastal Greenland and Arctic Canada. Simple discoidal vendobiont fossils (Aspidella terranovica) in the Dorchester Member of the Roxbury Conglomerate and in the Cambridge Argillite are in heterolithic shale–siltstone facies that are interpreted as intertidal to shallow marine environments. Local marine transgressions and other paleosols showing significant chemical weathering represent temperate interglacial paleoclimates. Short glacial advances affecting climate and sea-level enable subdivision of the Ediacaran Period. Four distinct glacial advances and sea-level retreats punctuated Ediacaran time: Gaskiers (580 Ma), Fauquier (571 Ma), Bou-Azzer (566 Ma), Hankalchough (551 Ma). Paleosols with distinctive structures such as ice wedges were periglacial. Squantum Member diamictites near Boston, Massachusetts are Gaskiers age. [ABSTRACT FROM AUTHOR]

Many distinct glacial episodes in the past ~1 million years in the Central Lowlands of North America left behind a patchwork of glaciated landscapes of different ages and formed through different glacial, paraglacial, and proglacial processes. Herein, we synthesize and reconcile diverse data sources across nine states in the Central Lowlands to create a generalized landform regions map, incorporating information from surficial geology, ageconstrained glacial boundaries, soil properties and parent material, and topography. The resulting map presents regions of till plains, moraines, outwash plains, and glacial lakes with ages ranging from 10.2 cal ka BP to greater than 500 cal ka BP. This new map improves on regional perspectives of the glaciated Central Lowlands by modifying and reconciling boundaries to agree with a variety of spatial data sources with finer detail. This refined map enables a more accurate spatial analysis of the landform regions by reducing noise from imprecise boundaries. [ABSTRACT FROM AUTHOR]

During the Pleistocene and Holocene, large-scale climatic changes occurred, resulting in severe environmental changes. Such changes in the Carpathian Basin were examined using dental elements of cervids from localities of Slovakia and Hungary. Their dental wear and the stable carbon and oxygen isotope values of structural carbonate and phosphate in bio-apatite of enamel were measured. Dental wear reflects the long and short-term changes of past vegetation, and stable isotope analyses can be used to uncover palaeotemperature and photosynthetic pathways of the consumed plants, thus indirectly providing information on the vegetation. The changes of mesowear scores, from the early Pleistocene onwards, indicate a gradual transition from a more or less closed to an open environment, as climate got cooler. The results of microwear analysis suggest that even though the environment became more open, some tree cover remained in the Carpathian Basin, even in the glacial periods. Based on the measured δ18O values for glacial periods, estimated temperatures were approximately 5–6°C cooler, whereas for interglacials, temperatures were similar to the recent climate of Hungary. The δ13C values of the examined cervids suggest predominantly C3 plant consumption, which agrees with the fact that C4 plants are scarcer in colder environments. [ABSTRACT FROM AUTHOR]

Dense networks of dilated fractures occur locally in the upper 5–15 m of bedrock in basement gneisses in eastern Sweden. Near Forsmark, pre-existing sub-horizontal fractures have been jacked open and filled with water-lain sediment, likely during the latest Weichselian glaciation. Despite extensive previous research, it is uncertain whether subglacial hydraulic jacking led to the generation of new fractures, in addition to reactivation of pre-existing ones. Re-analysis of historic photos from excavations near the Forsmark power plant indicates formation of two types of new fracture. Firstly, rock fragments were broken off the main fracture surfaces as existing fractures were jacked open. Secondly, fracture analysis shows that whilst few subvertical fractures occur above tight sub-horizontal fractures, a higher density of vertical fractures occurs above dilated sub-horizontal fractures, suggesting new formation. We apply a model of beam failure theory, borrowed from structural engineering, to constrain potential new fracture generation, using assumptions based on measured water pressure fluctuations from beneath the Greenland Ice Sheet. This modelling shows that beam failure is a plausible mechanism for the generation of new vertical fractures during a subglacial water fluctuation cycle under a range of realistic glaciological conditions. This implies that hydraulic jacking can result in further in situ disruption and brecciation of the shallow rock mass, decreasing the rock mass strength and increasing its hydraulic conductivity. Altogether, hydraulic jacking of existing fractures and the formation of new vertical fractures results in effective subglacial mechanical weathering of the shallow rock mass. [ABSTRACT FROM AUTHOR]

The published latest Palaeocene to Early–Middle Eocene age limits of the Sabrina microfloras, offshore Aurora Subglacial Basin, East Antarctica, largely depend on 1970s age-range data for fossil pollen and spore species in the continental margin basins of southern Australia. This paper uses updated biostratigraphical data from southern Australia, including the basins closest to the Aurora Basin throughout the Late Cretaceous and Paleogene, to propose that the age of the terrestrial component of the Sabrina microfloras is Campanian to Maastrichtian, not Paleogene. However, the revised age limits do not preclude these microfloras being redeposited more or less intact during the development and expansion of ice-sheets on East Antarctica, i.e. most probably during the late Paleogene based on other evidence from East Antarctica. [ABSTRACT FROM AUTHOR]

When you are missing pieces from the jigsaw, the result may be attractive and even comprehensible, but it is incomplete. The conventional geological picture of the 'Traralgon Formation' in the Gippsland Basin includes a variety of ages, uses and concepts, and the formation's type section at Loy Yang has never been dated by palynology. The inclusion of new palynological data from bores at Loy Yang and elsewhere in the onshore part of the Gippsland Basin presents a more complete picture that reinterprets the age and distribution of the coal seams. The new data indicate that the Traralgon Formation coal seams in the Loy Yang area of the Latrobe Valley and the Lake Wellington Depression mostly comprise the youngest T0 coal seams, with Upper Nothofagidites asperus Zone (early Oligocene) ages. The Traralgon Formation coals in the Gormandale Syncline and Seaspray Depression, however, are mainly T1 and T2 coal seams of Middle and Lower Nothofagidites asperus Zone (late and middle Eocene) ages. The Rosedale Monocline, situated between the Latrobe Valley–Lake Wellington and Gormandale–Seaspray depressions, acted as a hinge that reversed movements at the Eocene–Oligocene boundary. Using quantitative palynology, the paleoclimates of the T0 seam are examined where it straddles the transition between the Eocene 'greenhouse' and the Oligocene 'icehouse'. In the Seaspray and Lake Wellington depressions below the T0 coal is an up to 150 m-thick regressive barrier sand of the upper Eocene Dutson Sand Member. The regression indicates that the climate transition began before end-Eocene and continued into the lower T0 coal. Mean annual temperatures (MATs) fell sharply from 16–17 °C to 14–16 °C to be ≤14 °C in the latest Eocene–earliest Oligocene. The lower T0 coal seams comprise a semi-continuous terrestrial record through the earliest Oligocene (the Oil glaciation event), marking the first significant glaciations in Antarctica. The upper part of T0 seam indicates a warmer, mesothermal climate, and MATs generally within the range of 14–16 °C. New palynology indicates that in the Loy Yang, Latrobe Valley, and the Lake Wellington depressions, the thickest Traralgon Formation coal seams have an Upper Nothofagidites asperus Zone (early Oligocene) age. In the Gormandale Syncline and Seaspray Depression the major coal seams are T1 and T2 with Middle and Lower Nothofagidites asperus Zone (late and middle Eocene) ages. Using quantitative palynology the transition between the Eocene 'greenhouse' and the Oligocene 'icehouse' began in the upper Eocene Dutson Sand Member and continued into the lower T0 coal. The upper part of T0 seam indicates a warmer, mesothermal climate, and mean annual temperatures generally within the range of 14–16 °C. [ABSTRACT FROM AUTHOR]

Northern British Columbia was repeatedly covered by the Cordilleran Ice Sheet (CIS) during the glacial periods. However, its mountainous terrain and remote location have thus far impeded our understanding of the central sector of the ice sheet. The improved resolution of remotely sensed data provides new opportunities to unravel the glacial history of this inaccessible location. Here, we present a comprehensive map of glacial landforms for the central sector of the CIS (55° to 60° N). Seven landform categories were mapped: ice flow parallel lineations, moraines (CIS outlet glacier moraines, Late Glacial moraines and moraines of unknown origin), meltwater channels (lateral and submarginal, subglacial, proglacial, and meltwater channels of unknown origin), kame terraces, eskers (single ridges and esker complexes), perched deltas and subglacial ribs. Collectively, these landforms provide a record of the extent, thickness and behaviour of the CIS, the direction of its movement and pattern of ice retreat. [ABSTRACT FROM AUTHOR]

Since the discovery of glacial features on sub-Antarctic Marion Island, the character and extent of a historic glacial period have remained an important research focus for earth science investigations. Previous glacial reconstructions were limited to mostly pre-GPS field observations and pre-digital mapping through a Geographic Information System. With the aid of GPS field mapping, high-resolution satellite imagery and a digital surface model with a 1 × 1 m cell resolution, this paper provides a comprehensive, geo-rectified spatial geodatabase and map of Marion Island's glacial geomorphology. The geodatabase includes an inventory of glacial erosional (e.g. striations) and depositional (e.g. moraines) features compiled from existing records as well as new features mapped from recent field observations. The final map and the geodatabase, which is downloadable as ESRI layerpackage files, will aid future field investigations and modelling applications to understand Marion Island's Quaternary landscape evolution and post-glacial ecological succession. [ABSTRACT FROM AUTHOR]

This study presents a 1:25,000 geomorphological map of the northern sector of Ulu Peninsula, James Ross Island, Antarctic Peninsula. The map covers an area of c. 250 km², and documents the landforms and surficial sediments of one of the largest ice-free areas in Antarctica, based on remote sensing and field-based mapping. The large-scale landscape features are determined by the underlying Cretaceous sedimentary and Neogene volcanic geology, which has been sculpted by overlying ice masses during glacial periods. Paraglacial and periglacial features are superimposed upon remnant glacial features, reflecting the post-glacial evolution of the landscape. The study area can be broadly separated into three geomorphological sectors, according to the dominant contemporary Earth-surface processes; specifically, a glacierised southern sector, a paraglacial-dominated eastern sector, and a periglacial-dominated central/northern sector. This map provides a basis for further interdisciplinary research, and insight into the potential future landscape evolution of other parts of the Antarctic Peninsula as the climate warms. [ABSTRACT FROM AUTHOR]

The Ottfjället Dyke Swarm (ODS) is a prominent component of the Ediacaran mafic magmatism associated with opening of the Iapetus ocean, and hosted in the Särv Nappe, Middle Allochthon of the Scandinavian Caledonides. A U-Pb baddeleyite age of 596.3 ± 1.5 Ma for a thick, well preserved, plagioclase-phyric dolerite dyke in Härjedalen, Sweden, dates emplacement of the swarm. The age represents a robust, inheritance-free reference age for variably deformed and metamorphosed tholeiitic dykes in sandstone-dominated sequences of the lower part of the Middle Allochthon, representing the proximal, rifted Baltoscandian margin preceding the opening of Iapetus. The new age is within the narrow time span between 610 and 595 Ma defined by the most reliable age estimates for mafic dykes in structurally higher nappes (upper part of Middle Allochthon), representing the distal margin during the opening of Iapetus. The Ottfjället Dyke Swarm cuts the Tossåsfjället Group succession, which includes sabkha-related carbonate platform and diamictite couples, one of several correlated Neoproterozoic glaciogenic successions in Scandinavia. The intrusion age of ca. 596 Ma therefore sets a minimum age for the glaciogenic successions. It implies that Neoproterozoic glaciations in Scandinavia predate the ca. 580 Ma Gaskiers glaciation event and are probably part of the ca. 635 Ma Marinoan "Snowball-Earth"-type glaciation. [ABSTRACT FROM AUTHOR]

In this study, the lichenometry studies of the Hoksar Glacier valley in Kashmir Himalaya, India supported by the extensive ground- and remote sensing-based glacial geomorphological mapping enabled the identification of the six episodes of glacier advances in the valley. Field-based geomorphologic evidence suggests that the glacial episode 1 (GEI) experienced the most extensive glaciation in the Hoksar valley extending ∼1 km down the valley (altitude 3565 m) from the current snout position of the Hoksar Glacier (altitude 3680m). Lichenometric dating of the moraines suggests that the GE1 episode is chronologically the oldest (∼480 ± 25 years) and GE6 episode the youngest (∼245 ± 10 years). The mean equilibrium line altitude (ELA) during the GE1 episode was calculated as 3755 ± 4 m compared to the observed present ELA position of 4060 ± 5 m, an upward shift of 305 m observed during the period. The spatio-temporal changes of the Hoksar Glacier during different episodes of the glacier advances until 2018 showed that the glacier area has shrunk from ∼212 ha during the GE1 to 100 ha at present losing an area of 112 ha (52%) during the period mainly as a result of the recent climate change. The recent observed glacier recession (1980–2018) is much higher (11 000 m2 a−1) compared to the past recession (1300 m2 a−1). The study provides valuable insights about the glacier recession in the Kashmir Himalayan region during the Late Holocene where knowledge about the past glacial history on a regional scale is generally poorly investigated. [ABSTRACT FROM AUTHOR]

Island ecosystems can be severely affected by climate change as they provide limited opportunities for species to track their habitat. Studying the population dynamics of keystone species from these ecosystems can shed a light on climate – ecosystem interactions. Southern beeches are such keystone species in New Zealand with beech forests constituting the most abundant forest cover on the two main islands. Here we use 2.4 kilobase pairs of chloroplast genetic markers from four species of southern beech across their geographic distribution to help elucidate the Pleistocene history of New Zealand forests, and the processes that led to the present-day distribution of southern beech diversity. Broadly concordant phylogeographic patterns were observed across all beech species analysed. The centre of genetic diversity in silver beech was in the northern South Island, with unique haplotypes in the southern South Island, and southern and northern North Island, separated by known 'beech gaps'. Significantly less genetic diversity was evident in the subgenus Fuscospora (red, hard, black/mountain beech). All three species shared a single haplotype in the southern South Island, and a unique haplotype north of the central South Island 'beech gap'. Our study indicates that the present-day distribution of southern beech diversity in New Zealand is largely a result of Plio-Pleistocene environmental changes, with survival in cryptic southern South Island and multiple North Island in situ microrefugia throughout recent glacial cycles. By contrast, the northern South Island was likely the only New Zealand region that supported large (silver) beech populations throughout the Pleistocene. With beech species in New Zealand being keystone forest species, the distribution of the genus throughout the Pleistocene provides a proxy for forest cover at different times. It helps understand the ecological challenges the New Zealand forest fauna and flora were exposed to during the climate oscillations of the ice ages. [ABSTRACT FROM AUTHOR]

Mountain glaciers are useful climatic indicators in alpine regions where instrumental climate observations are sparse. Here we review the state of understanding of past and present glaciation in North Island, New Zealand. During the last glacial, mountain glaciers descended to ∼1200 m on both Ruapehu and Tongariro. Glacier modelling indicates that air temperatures during the Last Glacial Maximum were 5–7°C lower than present. Under such conditions, favourable topoclimatic mass balance processes (e.g. snowblow, shading) may have promoted marginal glaciation in lower-elevation North Island mountain ranges. The timing and magnitude of North Island glacier changes are broadly consistent with moraine chronologies and climatic reconstructions from glaciers in the Southern Alps. As of 2016, several glaciers and multi-year snow patches persist in North Island (totalling 3.0 km2 – a 25% reduction in area since 1988), all situated on the summit region of Ruapehu volcano. Mass balance of these glaciers is modulated by topoclimatic factors and debris cover, which may reduce rates of mass loss in the near term. However, given the proximity of the present equilibrium line altitude to the summit elevation of Ruapehu, complete loss of the present glaciers is probable under even moderate warming scenarios predicted for the coming decades. [ABSTRACT FROM AUTHOR]

The central Meseta is a high plateau located in the heart of the Iberian Peninsula. Abundant evidence of Lower and Middle Palaeolithic occupations of the region contrasts with scarce evidence of a human presence during the early Upper Palaeolithic. On this basis, it has been suggested that climatic downturns triggered the temporary abandonment, or near abandonment, of the central Meseta during the Last Glacial period. We conducted three archaeological surveys in Guadalajara province, located in the southern part of the region, in 2009, 2010, and 2017. Survey results, interpreted in the light of a habitat suitability model, support a hypothesis of climate-driven abandonment (or near-abandonment) of the central plateau during the Last Glacial Maximum and suggest that the Tagus River Valley, which links the Spanish interior to the Atlantic seaboard, was a focus for the Palaeolithic occupation of the region at other times. [ABSTRACT FROM AUTHOR]

The Tarim Craton, China, records several significant events in the history of the Rodinia supercontinent, including Neoproterozoic glaciations and rift evolution. In this study, we use geochronological, geochemical, and geophysical data from the Aksu region, northwest Tarim Craton, to investigate the rifting history and three discrete Cryogenian glaciations in the Tarim Craton. A total of 268 concordant zircon U–Pb ages were obtained from three samples in the lowermost unit of the Cryogenian Xifangshan Formation. These ages define four Neoproterozoic populations of ca. 975–900, 885–810, 795–755, and 740–720 Ma, which reflect magmatic events in the Rodinia supercontinent. The age of the Xifangshan Formation is constrained by two maximum depositional ages of 739 ± 9 Ma and 719 ± 7 Ma, suggesting a stratigraphic correlation with the Cryogenian Baiyisi Formation in the Kuruktag region, northeast Tarim Craton. Field and geochemical evidence identify three discrete Cryogenian glaciations in the Aksu region, which are the Xifangshan, Qiaoenbrak, and Youermeinark glaciations that can be chronologically correlated with the Baiyisi, Altungal, and Tereeken glaciations in the Kuruktag region, respectively. The northern rift basin in the Aksu region formed at ca. 740 Ma and is filled by a thick Cryogenian volcanic–sedimentary succession. This rift basin gradually expanded to entire northern Tarim Craton, with sediments being unconformably deposited on underlying formations. Although large-scale deformation occurred in the late Ediacaran, corresponding to the Pan-African orogeny, the Aksu rift depocentre was covered with a series of deep-water rocks in the Early Cambrian and Ordovician. [ABSTRACT FROM AUTHOR]

In low relief Precambrian gneiss terrain in eastern Sweden, abraded bedrock surfaces were ripped apart by the Fennoscandian Ice Sheet. The resultant boulder spreads are covers of large, angular boulders, many with glacial transport distances of 1–100 m. Boulder spreads occur alongside partly disintegrated roches moutonnées and associated fracture caves, and are associated with disrupted bedrock, which shows extensive fracture dilation in the near surface. These features are distributed in ice-flow parallel belts up to 10 km wide and extend over distances of >500 km. Our hypothesis is that the assemblage results from (1) hydraulic jacking and bedrock disruption, (2) subglacial ripping and (3) displacement, transport and final deposition of boulders. Soft sediment fills indicate jacking and dilation of pre-existing bedrock fractures by groundwater overpressure below the ice sheet. Overpressure reduces frictional resistance along fractures. Where ice traction overcomes this resistance, the rock mass strength is exceeded, resulting in disintegration of rock surfaces and ripping apart into separate blocks. Further movement and deposition create boulder spreads and moraines. Short boulder transport distances and high angularity indicate that glacial ripping operated late in the last deglaciation. The depths of rock mobilized in boulder spreads are estimated as 1–4 m. This compares with 0.6–1.6 m depths of erosion during the last glaciation derived from cosmogenic nuclide inventories of samples from bedrock surfaces without evidence of disruption. Glacially disrupted and ripped bedrock is also made ready for removal by future ice sheets. Hence glacial ripping is a highly effective process of glacial erosion. [ABSTRACT FROM AUTHOR]

Stratigraphic investigations, supported by palynological dating, detrital zircon and monazite dating, and quartz grain micromorphology were undertaken of the Early Cretaceous strata around the southern margin of the Eromanga Basin where they onlap older rocks of the northern Flinders Ranges. The presence of a tillite within the Early Cretaceous Cadna-owie Formation and another in the Trinity Well Sandstone are evidence of two significant glaciations: the oldest, the Livingston Tillite Member, is from the middle Valanginian; the younger, the Sheehan Tillite Member, is from the early Aptian. A significant hiatus encompassing the Barremian interrupts the succession. Extensive dropstones, minor diamictite lenses and beds and a bed containing glendonite crystals, together indicate that cold (limited glacial and/or seasonal freezing) conditions persisted through the Hauterivian and the Aptian, with cold conditions peaking in the late Aptian. [ABSTRACT FROM AUTHOR]

The present marine Baltic Sea basin (BSB) occupies an eroded Proterozoic intra-cratonic basin on the Fennoscandian shield. Competing models propose a Neogene fluvial origin, with later modification by glacial erosion, or a much younger development, with overdeepening beneath the Fennoscandian Ice Sheet (FIS). We test these alternatives using a first order source to sink sediment budget for the catchment of the BSB. Best estimates derived from geomorphic and cosmogenic nuclide evidence suggest depths of erosion over the last 1 Ma of 20 m in basement and 40 m in sedimentary rocks that surround the BSB. As the BSB has been overdeepened below a regional base level provided by the shallow Darss Sill at the boundary with the Kattegat, erosion of the BSB may be interpreted as glacial in origin, without a fluvial component. The estimated total volume of source area erosion is 30,628 km3 of which 87% is derived from the present BSB. Sediment volumes in the sink area within the limits of maximum Pleistocene glaciation are estimated at a minimum of 37,629 km3, after correction for local erosion, porosity, and carbonate losses. Marine Isotope Stage 12 and younger sediments account for 87% of the total Pleistocene sediment volume in the sink in Poland. Although significant uncertainties remain, the sediment budget is consistent with erosion of the BSB entirely by the FIS, mainly when the ice sheet reached its maximum extent and thickness during the Middle and Late Pleistocene glaciations. [ABSTRACT FROM AUTHOR]

Although the historical and modern distributional range of the European spring snail genus Marstoniopsis has already been considered in the context of Pleistocene/Holocene glaciations, many details of the eastern limits of these taxa remain uncertain. Also, the taxonomic status of some nominal species commonly attributed to this genus needs to be clarified. In the present study, a literature review of Marstoniopsis and the addition of newly found populations and fossils allow a reconstruction of the geographical and population history of this genus. Results indicate that the majority of the range of Marstoniopsis is inhabited by M. insubrica (Küster, 1853), though several local endemic taxa probably represent distinct species: M. armoricana (Paladilhe, 1869), M. croatica Schütt, 1974, M. vrbasi Bole et Velkovrh, 1987 and M. graeca (Radoman, 1978). The populations in the middle parts of the Dnieper and Volga rivers mark the south-eastern limit of the distribution of Marstoniopsis. Localities along with the eastern distribution limit of the range in European Russia and Ukraine mostly conform to the configuration of the zone of maximal (Riss-Saale-Dnieper) glaciation. Fossil records from Hungary and Slovakia show that Marstoniopsis inhabited central Europe (where these snails are now absent) at least during the early Holocene. It is here suggested that during the whole Pleistocene and Holocene the historical range of Marstoniopsis pulsated in accordance with the area size occupied by the glaciations. The overall geographic range of these snails includes the basins of rivers flowing into the North, Baltic, Black and Caspian seas. Isolated occurrences in Europe are mainly in closed lakes in mountainous areas of the Alps and the Balkans and are considered as refugia in the southern side of the Alps. [ABSTRACT FROM AUTHOR]

Mitochondrial DNA cytochrome b and d-loop sequences (2,137 bp) in 65 specimens of Sarcocheilichthys sinensis from five populations were identified as two lineages (I and II). The pairwise genetic distance between lineages I and II was 1.94%. SAMOVA analyses suggested that the best grouping occurred at three groups, Yangtze, Qiantang and Minjiang Rivers. High haplotype diversity (0.949) and low nucleotide diversity (θπ = 1.067%) were detected. The results of the neutrality tests, mismatch distribution and approximate Bayesian computation (ABC) did not support demographic expansions. The results of phylogenetic analysis, statistical dispersal-vicariance analysis (S-DIVA), ABC, MIGRATE-N and the time to the most recent common ancestor (TMRCA) indicated two colonization routes. First, before the Wuyi Mountains lifted, S. sinensis dispersed from the Yangtze River to the Minjiang River. Second, during glaciation, the continental shelf was exposed, which contributed to the dispersion of populations from the Yangtze River. [ABSTRACT FROM AUTHOR]

The Flinders Ranges in South Australia mainly comprise folded Neoproterozoic to Cambrian sedimentary rocks of the Adelaide Geosyncline, with local inliers of its Paleo–Mesoproterozoic igneous and metamorphic basement. A widely varied range of exceptional geological features is displayed in the rocks of the ranges and forms the basis of a proposal for recognition as a UNESCO World Heritage Serial Property. Abundant fossil evidence is revealed of the evolution and diversification of Earth's early life forms, and these rocks showcase the increasing complexity of life with time, from single-celled life forms and stromatolites, organo-sedimentary structures resulting from microbial life-activity, through multi-cellular organisms such as the Ediacara biota and builders of giant reefs to animals with shells and burrowing, predatory and scavenging behaviour in the early Cambrian. This took place during a time span of over 300 million years of extreme climatic oscillations and fluctuations of ocean and atmospheric composition, punctuated by two global glaciations. The geological evolution of this basin was modified by its radiogenic, unstable basement and mobile salt tectonics and diapirism, which provide a unique natural laboratory for studies of these aspects and, particularly, the possible genetic and causative relationships between them. Added to this unique history are an interval of flood basalt extrusion, sedimentary ironstone deposition accompanying glaciation, a debris layer from a bolide impact and deep canyon incision. Indeed, this unique basin evolution history is likely to have influenced the progress of its biotic evolution. Further, the thermal effects of the radiogenic basement have continued until the present day, as revealed in Paleozoic magmatism, hydrothermal features and hot springs. The Ediacaran, the first geological period defined in the southern hemisphere, and the first for over 100 years, has its defining GSSP (Global Stratotype Section and Point) in the Flinders Ranges. [ABSTRACT FROM AUTHOR]

Exhumed Paleozoic glacial deposits and landforms of the North Gondwana are reported here for the first time from the South Eastern Desert (SED) of Egypt. Using field observations and remote sensing datasets (Advanced Land Observing Satellite [ALOS], Phased Array L-band Synthetic Aperture Radar [PALSAR] radar, multispectral Landsat TM datasets, and digital elevation models [DEMs]), we mapped the distribution of Paleozoic glacial features (i.e. deposits and landforms) in the SED. Two main glaciogenic facies were identified in three locations in the SED: (1) massive, poorly sorted, matrix supported, boulder-rich diamictites in Wadi El-Naam and Korbiai, and (2) moderately-sorted, occasionally bedded outwash deposits in Betan area. Inspection of radar, DEMs, and Landsat Operational Land Imager (OLI) images revealed previously unrecognized ENE-WSW trending glacial megalineations (MLs) over the peneplained Neoproterozoic basement rocks in the central sections of the SED, whose trends align along their projected extension with those of glacial features (tunnel valleys and striation trends) reported from Saudi Arabia. The glaciogenic features in the SED are believed to be largely eroded during the uplift associated with the Red Sea opening, except for those preserved as basal units beneath the Nubia Sandstone Formation or as remnant isolated deposits within paleo-depressions within the basement complex. The apparent spatial correlation of the SED glacial features with well-defined Late Ordovician deposits in North Africa and in Saudi Arabia, and the reported thermochronometric analyses and fossil records are consistent with a Late Ordovician age for the SED glaciogenic features and support models that call on the continuation of the Late Ordovician (Hirnantian) ice sheet from the Sahara into Arabia through the SED of Egypt. [ABSTRACT FROM AUTHOR]

Seabirds are higher-order predators in the marine ecosystem and hence good indicators of the marine environment. Although the North Pacific has been the focal area for investigations of seabird faunal dynamics, the Pleistocene seabird fossil record has been scarce in the western North Pacific. Here, remains of 32 species of seabirds and related taxa (Anatidae, Podicipedidae, Gaviidae, Diomedeidae, Hydrobatidae, Procellariidae, Phalacrocoracidae, Scolopacidae, Laridae, and Alcidae) are reported from the middle–late Pleistocene Shiriya local fauna, northeastern Japan (Marine Isotope Stages 9 and 5e, ~ 320 and ~ 120 ka). This is the first substantial Pleistocene seabird fauna reported from the region so far, and includes globally first fossil records for Cepphus carbo and extant species of Aethia. The fauna also includes three extinct species, Shiriyanetta hasegawai, Mancalla? sp., and Uria onoi, the former two of which were flightless. The occurrence of immature individuals indicates that at least two species had nearby breeding sites. The seabird populations had probably been sustained by enhanced oceanic productivity in this area during their age, but oceanographic fluctuations in the subsequent glacial period, including the probable disappearance of a nearby oceanic front, would have seriously affected their subsistence, likely causing local extinctions of some species. [ABSTRACT FROM AUTHOR]

In the northern lakes of Yakutia, Vorota and Labynkyr, which are 2100 kilometres northeast of Lake Baikal, we found a putative Lake Baikal endemic, Lindavia minuta. Morphological analysis and non-metric multidimensional scaling showed that L. minuta populations from Yakutian and Transbaikalian lakes belong to the same (morpho) species. The possible dispersal history is discussed. The most probable hypothesis is that L. minuta was present in the Baikal basin during several Pleistocene glaciation cycles, and since Lake Baikal was previously connected to the River Lena, it is possible that there was a stable population of this species in the river, and that the river carried some cells to other suitable habitats. During glaciated periods, L. minuta could also have survived for longer periods in several ice dam lakes and possibly dispersed further north-east to the lakes in Yakutia. [ABSTRACT FROM AUTHOR]

The morphologically similar populations of the Korean freshwater spined loach recently described as a new species Cobitis nalbanti (Actinopterygii: Cypriniformes: Cobitidae) inhabit the rivers and streams on the Korean Peninsula that flow into the Yellow Sea and the Korea Strait. These shallow sea areas have experienced recurrent sea-level rises and falls. In this study, we investigate the impact of repeated disconnection and reconnection of rivers on the population genetics and morphological variation of C. nalbanti. A total of 264 individuals of C. nalbanti were collected from 17 localities covering the entire distribution range of this species in South Korea. We examined multi-locus genetic data including a mitochondrial gene, seven nuclear genes and eight microsatellite loci, and scrutinized 31 morphological variables based on 26 morphometric and 3 meristic characters. We uncovered a population genetic structure and noticeable morphological variation among populations approximately corresponding to the geography of river basins along the Yellow Sea. Overall genetic diversity was significantly reduced in the more northern populations, suggesting range expansion from ancestral southern populations into northern rivers via the paleo-Yellow River system in the Yellow Sea during glacial periods of lowered sea levels. A northward range expansion hypothesis was strongly supported by the reconstruction of geographic ranges of ancestral species and/or populations based on phylogenetic analyses. Both mitochondrial and nuclear phylogenetic trees revealed a relatively highly divergent lineage of C. nalbanti in the southernmost populations (Tamjin lineage). Noticeable differences in morphological variables between the Tamjin lineage and other lineages of C. nalbanti also suggest potential separate specific status of the former. The close phylogenetic relationships between the Tamjin lineage and the Japanese species of Cobitis signify interaction or exchange between the Korean and Japanese cobitids and imply that there was historically at least one freshwater passage on the terrestrial bridge between the Korean Peninsula and the southwestern part of the Japanese archipelago. [ABSTRACT FROM AUTHOR]

Inocybe (Inocybaceae) is one of the most diverse ectomycorrhizal genera in arctic and alpine habitats where the primary hosts are Salix, Betula, and Dryas. Subgenus Inocybe is common in these habitats and typically characterized by the presence of thick-walled pleurocystidia. Here, we focus on species that have angular or nodulose spores. Historically, over 30 taxa from this group have been reported from arctic and alpine habitats. Many names have been synonymized, whereas molecular analysis has revealed new species. Nuc rDNA internal transcribed spacer ITS1-5.8S-ITS2 (ITS) sequence data of 26 type specimens in this group now allow for further taxonomic clarification and comparison across continents of disjunct populations. Here, we compare ITS sequence data and the D1–D2 portion of nuc 28S rDNA (28S) from Rocky Mountain specimens with those of types and European reference material. We report 10 species from the Rocky Mountain alpine zone, all of which are conspecific with known European boreal, montane, or alpine species, and four are described as new; all have intercontinental distributions. Nodulose-spored Inocybe taxa that occur in the Rocky Mountain alpine zone include I. alpinomarginata, sp. nov., I. arctica, I. giacomi, I. leonina, I. murina, sp. nov., I. occulta, I. paragiacomi, sp. nov., I. phaeocystidiosa, I. purpureobadia, and I. subgiacomi, sp. nov. Remarkably, these species occur at elevations up to 4000 m and at latitudes as low as 36°N, hundreds of miles from the Arctic, the European alpine, and original type localities. Distributions are explained in part by host distributions and historical glaciation patterns. A key and full descriptions for Rocky mountain species are provided to promote species recognition. [ABSTRACT FROM AUTHOR]

Influence of nanoparticles of the clay nanomaterial laponite on the crystallization process of various polymorphic phases of the composite TPP/laponite was studied by infrared spectroscopy and differential scanning calorimetry method. It was shown that the presence of clay nanoparticles leads to the formation of a new crystalline phase of the composite stable at room temperature, which melts at 306.8 K. It was also shown that in this stable phase conformers of TPP molecule dominate, different from the conformers realized in other metastable phases of the composite. The glass transition temperature, as derived from the DSC heating curves, is found to be only minor influenced by the clay addition. [ABSTRACT FROM AUTHOR]

Several regions of tropical America show imprints of past glacial activity. These relict landforms can support the understanding of past climate conditions, such as during the Last Glacial Maximum (LGM), and the implications that these paleoclimatic conditions could have had on landscape change. Here, we present and analyze glacial morphologies for the Chirripó National Park in Costa Rica based on aerial imagery (1:25,000), detailed Digital Elevation Models, geomorphic mapping, as well as geomorphic assessments in the field to determine and validate landforms. This study adds valuable insights into the reconstruction of the maximum expansion of tropical glaciation during the LGM in Costa Rica and into tropical America glacial landscapes in general. [ABSTRACT FROM AUTHOR]

The Neoproterozoic glaciations represent a milestone in the Earth evolution due to their influence on atmosphere, biosphere and hydrosphere. Evidence for the Sturtian glaciation, the early stage of Cryogenian, has been recorded worldwide, but the precise timing and synchroneity of its counterpart, the Chang'an glaciation, in South China have been controversial. As such, new zircon U–Pb ages from the pre-Sturtian Gongdong Formation and the overlying the Chang'an Formation in southeastern Yangtze Block were reported. The youngest U–Pb zircon age from a tuff sample of the topmost Gongdong Formation was 716.8 ± 6.8 Ma, and that from a sandstone sample of the lower Chang'an Formation was 725.9 ± 4.4 Ma. The zircon weighted mean age of 716.8 ± 6.8 Ma was interpreted as the maximum depositional age of the termination of the Danzhou Group. This age, along with the ages reported from the bottom of the Danzhou Group, constrains deposition of the Danzhou Group to between ca. 820 Ma and ca. 715 Ma. The age of 716.8 ± 6.8 Ma from the top of the Gongdong Formation is consistent with the SIMS U-Pb age of 715.9 ± 2.8 Ma from the Sibao section, as well as ages from the Banxi Group, Liantuo Group, and Kaijianqiao Formation in the Yangtze Block, which further constrain the onset time of the Sturtian glaciation in South China at ca. 715 Ma. It is also, with uncertainties, consistent with ages from pre-Sturtian strata in Laurentia and Oman, which indicates a global synchroneity and extent for the Sturtian glaciation. [ABSTRACT FROM AUTHOR]

Cryptocercus cockroaches are remarkable for their similarity in external morphology while having a diversity in chromosome numbers. Most species are therefore delimited by karyotyping combined with phylogenetics. However, the investigation of chromosome diversity within a limited region is not well-studied, and the causes of their geographic distribution patterns remain unclear. Here, we applied a multipronged set of analyses that included external morphological analysis, chromosomal data, molecular species-delimitation methods and phylogenetic reconstruction after extensive sampling on the Western Sichuan Plateau (WSP) in western China. As a result, six new species were discovered, which increases the known species in WSP to 15. Multiple extinction-isolation events caused by the lifting of the Qinghai-Tibetan Plateau and by glacial periods likely account for the present-day distribution of WSP species. For Manchurian species, major extinctions may have been caused by the Quaternary glaciation and Cenozoic volcanic activities. We believe that three factors shaped the current distribution of Cryptocercus karyotypes: (1) a variability of chromosomes, (2) their low capability for dispersal, and (3) their vulnerability to climate change. [ABSTRACT FROM AUTHOR]

New Zealand's remote five Sub-Antarctic island groups are the only sub-aerial exposures of the ∼800,000 km2 Campbell Plateau portion of Zealandia. An up-to-date geological map, a summary of the current geological knowledge and a geological interpretation is presented for each island group. The oldest rocks are Early Paleozoic metasediments on Campbell Island/Motu Ihupuku. Granitoids dominate the Bounty Islands/Moutere Hauriri (Early Jurassic) and Snares Islands/Tini Heke (Early Cretaceous), form a small part of the Auckland Islands/Motu Maha (Late Cretaceous), and occur as rare Cretaceous xenoliths in tuffs on the Antipodes Islands/Moutere Mahue. The Campbell Island/Motu Ihupuku metasedimentary rocks are overlain by Late Cretaceous-Cenozoic basin sediments, which are in turn overlain by tuff and lava resulting from emergent intraplate volcanism. The Auckland Islands/Motu Maha and Antipodes Islands/Moutere Mahue stratigraphies are also related to emergent intraplate volcanism. Limited radiometric dating indicates that the Auckland Islands/Motu Maha breached the Southern Ocean in the Early-Middle Miocene, Campbell Island Volcano formed in the Late Miocene, and the Antipodes Volcano formed in the last 300,000 yrs. Basaltic dikes on the Snares Islands/Tini Heke are undated, and mafic dikes on the Bounty Islands/Moutere Hauriri are Mesozoic; it is unclear when these two island groups formed. The Auckland Islands/Motu Maha and Campbell Island/Motu Ihupuku have cirques, terminal and lateral moraines, till deposits and glacially carved fjords, and near-shore bathymetry indicates that all island groups exposed significantly larger areas during glacial periods. More work is required to understand the geological formation of these islands and their Southern Ocean climatic records. [ABSTRACT FROM AUTHOR]

Anderson Pond in eastern Tennessee is one of only a handful of sites in the interior southeastern US where researchers have developed pollen records that extend to the last full glacial period. Pollen data from the site have been widely used in regional syntheses and models of past vegetation and climate. Previous researchers either constructed age models that assumed continuous sedimentation from the Late Pleistocene to the present, and plotted pollen data by radiocarbon or calibrated ages (1976 core), or recognized the likelihood of hiatuses in the postglacial sediments, and plotted pollen data by depth (2007 cores). We present an improved chronology for the 1976 core based on prior delineation and dating of two hiatuses, and on new age modeling using AMS dates on macrofossils from cores collected in 2007. This new age model allows us to plot pollen and microscopic charcoal by age for the entirety of the record, and more accurately represents site history. Plotting pollen and charcoal assemblages by age using our new chronology highlights the long intervals of time that are missing from the postglacial record at Anderson Pond, while improving our ability to make use of proxy data from the fragmented sediments of this classic pollen site. [ABSTRACT FROM AUTHOR]

The morpho–environmental similarity between subsections Natrix and Viscosae has been pointed out as the reason for the genetic complexity of these groups of taxa. Based on this characterization a question emerges: could a very recent ongoing evolutionary process explain that morpho–environmental similarity? ISSR and cpSSR amplifications for 45 specimens belonging to taxa of Natrix and Viscosae subsections were developed, along their biogeographic distribution areas. Twenty-nine haplotypes were detected in the biogeographic area of both subsections, 79% were exclusive haplotypes, but the rest is shared between subsections Natrix and Viscosae species. Could that haplotype sharing be the result of potential hybridization between these taxa? Do current environmental conditions restrict the gene flow among taxa? The combination of ancestral genetic polymorphism, introgression, coalescence processes and periodic restricted environments (PRE) by glacial–interglacial environmental dynamics were discussed to explain the relevant percentage of exclusive haplotypes detected, as well as the persistence of shared haplotypes. These results are in accordance with the morpho–environmental proximity previously described for both subsections. [ABSTRACT FROM AUTHOR]

A new taxon of monodontid cetacean, Casatia thermophila, gen. et sp. nov., is here described on the basis of a partial skull from lower Pliocene (5.1–4.5 Ma) marginal-marine deposits of Tuscany (central Italy). This new taxon belongs to Monodontidae based on the presence of a medial exposure of the maxillae anterior and lateral to the external bony nares; it mainly differs from all other named monodontids by the presence of a median depression of the premaxillae anterior to the premaxillary sac fossae and by a medial margin of the premaxillary-maxillary suture that does not parallel the anterolateral profile of the external bony nares. Our phylogenetic analysis, the first including all taxa of Monodontidae, recovers Casatia as a crown monodontid, more closely related to Delphinapterus than to Monodon and sister group of an unnamed taxon from the North Sea. The holotype of Casatia represents the first and only fossil monodontid from the Mediterranean Basin. Taking its place beside abundant fossils of strongly thermophilic marine vertebrates, such as the bull shark Carcharhinus leucas, the tiger shark Galeocerdo cuvier, and the extinct sirenian Metaxytherium subapenninum, Casatia thermophila represents the strongest evidence supporting the hypothesis that monodontids once thrived in low-latitude, warm-water habitats. On the basis of our phylogenetic reconstruction, early relatives of the extant monodontids might have adapted independently to the high-latitude, cold-water environments they currently master. The definitive disappearance of the Neogene thermophilic monodontids could be attributed to the cooling episode that accompanied the onset of long-term Northern Hemisphere glaciation around 3 Ma. [ABSTRACT FROM AUTHOR]

Environmental and climatic conditions of the South American temperate grasslands (Pampas) during the Last Glacial Period have typically been regarded as mostly arid and cold, whereas humid and mild conditions such as those prevailing today may have been established only recently. This hypothesis has been built mostly upon fossil mammals that come from coastal areas and date from the end phase of this period and thus provide both temporally and geographically biased data. Other fossil vertebrates, including anurans, have been overlooked when addressing these conditions in spite of being potentially very informative due to their ecological requirements. Here, we analyze an anuran assemblage from the Last Glacial Period of the inland Pampas. In addition to the description of new records, we discuss the taphonomic settings and the correlation of the fossil-bearing beds with levels referred to the interstadial Marine Isotope Stage (MIS) 3 from other Pampean localities. Based on this evidence, together with what is known for extant anurans, we discuss the environmental and climatic conditions of the Pampas during the Last Glacial Period. The presence of Rhinella arenarum and, particularly, Ceratophrys ornata in the fossil assemblage and their persistence in the Pampas throughout the Quaternary suggest that the range of environmental changes in the region during the Last Glacial Period might have been more limited than has traditionally been acknowledged. In this regard, this study highlights the value of anuran fossil assemblages when addressing environmental and climatic conditions during the Quaternary. [ABSTRACT FROM AUTHOR]

Recently acquired seismic data in the eastern portion of the Amadeus Basin of central Australia have enabled disconformities at the base of both the Sturt and Elatina glaciogenic sequences within the Neoproterozoic succession to be mapped on a semi-regional scale. On a more detailed scale, along the shallowly shelving eastern flank of the basin, seismic data have revealed features that demarcate the transition from a grounded to floating, or possible absent, Sturt ice-sheet. Coincident with this transition is an extensive mound-like accumulation of glacial debris, some 10 to 15km wide, 300 m high and extending at least 150km subparallel to the northeast-southwest-oriented basin margin. This glacial debris entered the basin subglacially through meandering tunnel valleys, one of which can be mapped seismically. [ABSTRACT FROM AUTHOR]

Mitochondrial DNA cytochrome b sequences (1141 bp) in 229 specimens of Acrossocheilus paradoxus from 26 populations were identified as four lineages. The pairwise genetic distances among these four lineages ranged from 1.57 to 2.37% (mean=2.00%). Statistical dispersal-vicariance analysis suggests that the ancestral populations were distributed over mainland China and Northern and Western Taiwan. Approximate Bayesian computation approaches show that the three lineages in Taiwan originated from the lineage in mainland China through three colonization routes during two glaciations. The results indicated that during the glaciation and inter-glacial periods, the Taiwan Strait was exposed and sank, which contributed to the dispersion and differentiation of populations. Furthermore, the populations of A. paradoxus colonized Taiwan through a land bridge to the north of the Formosa Bank, and the Miaoli Plateau in Taiwan was an important barrier that limited gene exchange between populations on both the sides. [ABSTRACT FROM AUTHOR]