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The sedimentary record of fossil coastal lagoons is an under-explored archive of environmental change in ancient coastal domains. The significant continentality of coastal lagoons, the small volumes of their water bodies, very shallow depths and intermittent connectivity to oceanic aquafacies all result in a highly complex depositional system. The matrix micrite chemostratigraphy (carbon and oxygen isotope ratios) of two mid-Cenomanian shallow coastal lagoon sections in the western Lusitanian Basin, Portugal, are here presented in comparison to the geochemistry of different diagenetic carbonate materials. Geochemical evidence is placed against independent data from field observations, sedimentology, microfacies analysis, and ostracod palaeoecology. Marine ingressions and coastal lagoonal environments are recorded both in sedimentological, micropalaeontological and geochemical data sets. Intervals of more open, marine conditions are evidenced by overall higher (0 to 2‰) carbon and less 18O-depleted (− 3‰) isotope ratios. The opposing pattern is observed for periods of more restricted lagoonal conditions. The combination of a detailed ostracod palaeoecology with geochemical and sedimentological findings is considered a strength of this paper as it allowed to disentangle the complex geochemical signals of ancient coastal lagoonal deposits. The comparison with Recent coastal lagoons provided new arguments to clarify interpretations based on ancient records.

The carbon and oxygen isotope composition of well-preserved belemnite rostra and bulk carbonates from uppermost Aalenian to Lower Tithonian outcrops of the Pieniny Klippen Belt in the Carpathians is under discussion in this paper. New isotope and elemental data from the open marine basin in a rarely studied, northern part of the Tethys Ocean, corroborate the world-wide δ 13 C variations and global temperature changes of a seawater. The δ 13 C temporal trends display prominent positive shift in the Upper Callovian–Middle Oxfordian, as well as a declining trend in the Kimmeridgian–Tithonian interval. δ 18 O values of belemnite rostra suggest a decrease in temperatures during the latest Aalenian–Early Bajocian. The Upper Jurassic temperatures, estimated on the basis of oxygen isotope values and Mg/Ca ratios of belemnite rostra, indicate a warming of the seawater of ca. 5.5 °C in the Late Oxfordian–Early Kimmeridgian. This temperature rise is interpreted to be a result of the global climate warming present during the early Late Jurassic.

The widespread perception that buckwheat (Fagopyrum esculentum and F. tataricum) did not occur in western Eurasia prior to the Late Medieval is challenged by numerous pollen finds. We traced some 240 localities from the area with pollen or macrofossils attributed to Fagopyrum in (often much) earlier time-slices. This paper evaluates various explanations for these finds within the context of palaecological methods, vegetation history, and cultural development. The clear morphological characteristics make large-scale misidentification of the pollen unlikely. Although some records are suspect, contamination is improbable for the vast majority of the pollen diagrams. Also long-distance transport of pollen of Fagopyrum snowdenii or Oxygonum from Africa seems unlikely, as the pollen rain of that continent hardly contains that pollen. The option that Fagopyrum was present in western Eurasia already much earlier than the Late Medieval must therefore be seriously considered. Cultivated species may have reached the area by trade between the Mediterranean and eastern Chinese realms, which was regular since 2000 BCE. As the low pollen values argue against large scale cultivation, the taxon may merely have occurred as a weed, or its pollen was transported with other products and subsequently re-emitted. The pervasive notion that buckwheat was cultivated on large scale by the Scythians in the Ukrainian realm since 800 BCE is highly ambiguous and probably wrong. There are some indications that wild Fagopyrum or a related taxon may have occurred widespread in Eurasia during the Pleistocene glaciations and the early/middle Holocene, i.e. predating 2000 BCE.

Mortality curves are a valuable tool to study taphonomy and to infer population structure in ancient communities; however, they rely on the precise determination of ontogenetic ages of individual animals, which is often uncertain for fragmentary and isolated fossil remains. In this paper, we develop a new protocol to construct mortality curves for fossil rhinocerotids using both tooth rows and isolated teeth, based on dental wear. We tested and calibrated this protocol using 29 skulls and 18 jaws of extant rhinoceroses (Diceros bicornis, Rhinoceros sondaicus, and R. unicornis). We then applied it to four extinct rhinocerotid species from the late early Miocene locality of Beon 1 of Montreal-du-Gers, SW France: the teleoceratines Brachypotherium brachypus and Prosantorhinus douvillei, the basal rhinocerotine Plesiaceratherium mirallesi, and the early elasmotheriine Hispanotherium beonense. Findings allow us to estimate population structures of these rhinocerotids, based on the percentage of juveniles, subadults and adults. The mortality curves of Beon 1 rhinocerotids reveal several major periods of vulnerability: birth, weaning, sexual maturity, and middle-late adulthood. When compared to extant populations (D. bicornis, Ceratotherium simum, and R. unicornis) and other ancient case studies (Miocene of USA, Pleistocene of Southeast Asia and France), mortality rate curves from Beon 1 are similar in early and late life; however, they lack the increased socially-driven mortality that is observed between 25 and 50% of the potential lifespan in some populations of D. bicornis and in the Miocene teleoceratine Teleoceras proterum. The population structures of Pr. douvillei, Pl. mirallesi, and H. beonense are close to those of extant populations of D. bicornis. In contrast, adult specimens of B. brachypus are overrepresented at Beon 1, similarly to Aphelops malacorhinus at Love Bone Bed (USA), probably due to taphonomical bias. It is important to note that considering isolated or associated teeth alone results in significant differences in mortality curves and population structures at Beon 1, hence both samples should be studied.

This paper analyzes the distribution patterns of pollen and spore assemblages in modern surface sediments recovered from the bottom of the San Jorge Gulf (SJG) and from offshore sites, in relation to the location of different phytogeographic provinces surrounding the SJG, including the distant forest from southwestern Patagonia. Results reveal that pollen spectra are dominated by Chenopodiaceae-Amaranthaceae, Poaceae, Asteraceae subf. Asteroideae, Colliguaja integerrima and Ephedra sp.; which represents the vegetation adjacent to the SJG. Overall, the pollen distribution in surface sediments reflects the location of the different phytogeographic provinces and will be used as modern-analogues to document vegetation history around the SJG. Pollen assemblages also reveal the latitudinal variation of vegetation taxa in the Patagonian steppe, which is characterized by a slight increase in herbaceous pollen and a decrease in high shrubs (e.g. Colliguaja integerrima) towards the southern-central part of the SJG. Furthermore, we identified two pollen taxa from the southwestern Patagonian forest, Nothofagus and Podocarpus that could be used as indicators of past dynamics and variations of the Southern Westerly Wind Belt (SWWB) in the SJG during the Late Pleistocene and Holocene. High pollen concentrations are recorded at the central part of the SJG (480–8080 grains/g), while low concentrations are measured in the northern and southern parts of the Gulf, as well as at offshore sites (26–1806 grains/g). The pollen distribution in the study area is most likely governed by the SWWB in combination with the marine sediment composition and surface currents flowing through the SJG. Fil: Faye, Simon. Université Du Québec Á Rimouski; Canadá Fil: Rochon, André. Université Du Québec Á Rimouski; Canadá Fil: St Onge, Guillaume. Université Du Québec Á Rimouski; Canadá Fil: Vilanova, Isabel. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Museo Argentino de Ciencias Naturales "Bernardino Rivadavia"; Argentina

Terrestrial deposits of the Triassic-Jurassic transition are well developed in the Junggar Basin, located in the Haojiagou Valley of Urumqi, Xinjiang Uygur Autonomous Region of Northwest China. This paper describes the palynology of a 10 m thick lignite bed from the Upper Triassic Haojiagou Formation (Rhaetian) with the aim of reconstructing the palaeovegetation and palaeoenvironment of a peat-forming wetland near the Triassic-Jurassic boundary. The palynoflora contains both Eurasian and Gondwanan elements, and is dominated by the spores and pollen of Bennettitales, Corystospermales, Ginkgoales, and Gleicheniales. At the Triassic/Jurassic boundary (Hettangian), the palynoflora significantly changes as Cyatheales spores become the dominant elements. We analyze assemblages in terms of an Eco-Plant model, which assigns the parent plants of the palynomorphs into five groups based on humidity and four groups based on temperature, and uses multivariate statistical analyses to infer palaeoclimate and palaeoenvironmental conditions. Results suggest that the palaeoclimate of the Rhaetian was generally wet and subtropical with short seasonal drought periods. Our analysis shows that an Eco-Plant model may be a useful tool to reveal past vegetation patterns and climate changes, applicable to other Mesozoic assemblages.

In the comment on our paper (this issue), Zaton (2020) questions the conclusions reported in Blazejowski et al. (2019). We present further arguments defending our theses. Late Jurassic horseshoe crabs preserved in sediments of the Kcynia Formation, (Owadow-Brzezinki Quarry), lived in a restricted lagoon repeatedly subjected to dysoxia/anoxia, which promoted their excellent state of preservation. The palaeobiological interpretation of the traces visible on horseshoe crab exoskeletons is consistent with the occurrence of temporal oxygen deficiency.

We analyse the evolution of carnivoran guilds (body mass, locomotor pattern, and diet preference) across the Middle to Upper Miocene boundary based on a comparison of the carnivoran fauna from Steinheim (Mammal Neogene zone MN 7/8; Servallian to early Tortonian), and from the Eppelsheim Formation (Mammal Neogene zone MN 9/10; mid-Tortonian), Germany. Results reveal a massive faunal turnover between these two communties due to taxonomic differences up to the family level. Guild structures of both carnivoran faunas were similar, implying that Late Miocene taxa replaced Middle Miocene taxa in their respective niches rather than new ecological strategies being added to the guild. This is not surprising, as (1) the majority of Late Miocene taxa were derived from European Middle Miocene ancestors and mostly share their paleoecology, (2) of the few undisputed Late Miocene immigrant taxa (Eomellivora, Simocyon, Sivaonyx), only Eomellivora adds new ecological strategies to the guild, and (3) both faunas occupied the same kind of partly open woodland paleoenvironment. Our paper supports previous studies, suggesting that ecological diversity remains stable across the Middle to Upper Miocene boundary and that similar environments produce similar carnivoran guild structures irrespective of taxonomical composition.

The lower Permian continental succession of the Lodeve Basin (southern France) contains a rich tetrapod ichnofossil record. In this paper, we re-describe ~20 large footprints from the Autunian (Asselian) Lunas locality using new data and photogrammetric techniques. Analysis of the best-preserved footprints permits the recognition of two trackways of Ichniotherium cottae and we compare this material with all known Carboniferous–Permian occurrences of the ichnogenus. The large size, slow gait, footprint arrangement and depth pattern inferred from the trackways are consistent with a primitive diadectomorph, and suggest a progressive adaptation to more terrestrial locomotion. A synapomorphy-based track-trackmaker correlation indicates Limnoscelis or analogous forms as possible trackmakers. These footprints increase our knowledge of the ichnofaunal diversity of central Pangaea.

Extinct giant ground sloths are a common taxon in New World Quaternary deposits, but relatively little is known about individual species' behavior or social structure. In this paper, we investigate the development of the late-Pleistocene locality Tanque Loma on the southwest coast of Ecuador, which preserves remains of at least 22 individuals of the giant ground sloth, Eremotherium laurillardi in asphaltic sediments. Multiple lines of evidence suggest that these sloths may have congregated and died in a mass mortality event in a marshy riparian habitat. Such evidence includes (1) a dense, laterally-extensive, bonebed-style accumulation; (2) a multigenerational age structure with adult and large juvenile individuals well-represented; (3) sediments suggestive of a low-energy anoxic aquatic environment; and (4) the presence of abundant plant material consistent with digested fodder representing coprolites or gut contents of E. laurillardi. Taking observations from modern megafaunal ecosystems as an analogue, we suggest that this death event could have resulted from drought and/or disease stemming from the contamination of the wallow, paralleling situations observed among hippopotamus populations in watering holes on the present-day African savannah.

The proboscidean Notiomastodon platensis is widely recognized in the Pleistocene of Brazil, but direct evidence for its feeding behavior is scant. In this paper, we report palynological assemblages preserved in dental calculi to infer dietary preferences and habitats. Molar specimens (m1 and M3/m3) with significant calculus accumulation were examined from localities along the Coastal Plain (CPRS) and the Campanha region (western state in Pampa biome) in Rio Grande do Sul state, southern Brazil. Palynomorphs obtained from calculus were identified with light microscopy, and we applied species distribution modelling (SDM) for arboreal/shrub pollen taxa to investigate the environmental contexts for proboscideans during the Last Interglacial (LIG, 120 ka BP) and Last Glacial Maximum (LGM, 21 ka BP). Pollen assemblages indicate a generalist diet for N. platensis, and corroborate previous paleoecological studies. N. platensis from CPRS showed two patterns: the subadult individual was a specialized browser in wooded habitats, inferred from pollen taxa dominated by arboreal species (mainly Myrtaceae), while mature/senile adult individuals were dominantly grazers to mixed-feeders in open habitats inferred from herbaceous pollen (mainly Cyperaceae) mixed with woody elements. For the Campanha region, diet interpretation is difficult due to the absence of pollen; however, Poaceae phytoliths indicate that grasses may have been important food items, notably pooid C3 grasses. N. platensis potentially accessed a more heterogeneous environment with mixed open grasslands and forests around the LIG interval because of the larger extension of forest at the time. Grassland landscapes could have been more foraged by proboscideans around the LGM given the dry and cold climate conditions, which resulted in a northward retraction of forest.

A considerable Upper Albian sand lithosome, developed on the external margin of the Albian epicontinental sea in the Polish Jura Chain (Miechow Synclinorium, southern Poland), is recognized as a shallowing-up sequence within the generally transgressive Albian sands. In particular, burrows described as the ichnospecies Psilonichnus upsilon Frey Curran and Pemberton, 1984 have a particular ecologic and sedimentological significance, and constitute the primary focus of this paper. In the Glanow-Stroniczki section (Cracow Upland, southern Poland), such burrows seem to be a crucial tool in the interpretation of basin bathymetry, indicating a foreshore to backshore (beach) facies and probably recording a temporary break in sedimentation. They were infilled by sand with pebbles or pebble material, potentially during hurricane or strong storm action. Lithification of the burrow infillings and their enveloping concretionary halos should have progressed in a beachrock mode. The Glanow horst, composed of Jurassic biohermal limestones, was likely an emerged element that neigboured, or was surrounded by, a beach with active fauna. The Psilonichnus upsilon burrows in Glanow-Stroniczki closely resemble burrows of the modern ghost crab Ocypode. In modern settings, representatives of Ocypode are encountered in extremely shallow marine (foreshore/intratidal and backshore/supratidal) to dune environments. The ichnological data from Glanow-Stroniczki suggests that fauna behaviorally similar to Ocypode may have occupied the beach backshore (and to a lesser extent the foreshore) zone near the emerged Glanow horst.

Late Cenozoic sediments in the Linxia Basin of China, on the northeastern Tibetan Plateau, bear abundant fossils of the Hipparion fauna. From late Miocene times, these sections record a history of aridification in the Asian Interior, the evolution of the east Asian monsoon, and multiple uplifts of the Tibetan Plateau. In this paper, a new detailed magnetostratigraphic study of a sedimentary sequence from the Duikang (DK) section containing the Hipparion fauna is presented, to better understand interconnected ecologic and environmental changes. The 90-m-thick section reveals nine normal and nine reversed zones that span from chron. C5n.2n to chron. C3Ar or from chron. C4n.2n to chron. C2Ar, yielding magnetostratigraphic ages of ~8.1 Ma - 3.7 Ma for the studied section and 5.3 Ma for the Hipparion fauna-bearing bed. Combined with all the previous magnetostratigraphic ages of the fauna-bearing sediments in the Linxia Basin, Hipparion can be distinguished as mainly having lived during five periods: Phase I (11.5 Ma), Phase II (8.2 Ma), Phase III (6.3 Ma), Phase IV (~5.3 Ma) and Phase V (2.5 Ma). Based on comparison of climate records in the Linxia Basin with aridification records from surrounding regions and global cooling during the late Cenozoic, we suggest that the evolution of Hipparion from the Linxia Basin was mainly driven by continuous global cooling and tectonic uplift of the northeastern Tibetan Plateau since the late Miocene.

Extant turtles exhibit a range of ecological adaptations to terrestrial and pelagic marine habitats. Bone shell microanatomy, and specifically, qualitative and quantitative approaches to shell bone porosity, have been used to infer palaeoecology and habitat. However, such inferences are hindered by the lack of a comprehensive sampling of testudine taxa and, in some instances, of long bones of vertebrates other than turtles. In this paper, we carry out an osteohistological analysis of Testudinata shell bones, including 31 different taxa, both extant and extinct, of known habitats. Costal and peripheral elements of published species and new data presented here are statistically analysed. Although, in some cases, values are congruent with those expected for a particular habitat (e.g. Hydromedusa casamayorensis), this is not true for all taxa examined. Moreover, microanatomical features of several taxa (e.g. Chelonia mydas) are inconsistent with habitat data. Results indicate that, although the microanatomical structure of the shell is related to habitat, this is not the only influence and indeed, in several cases, not the most important factor.

A comprehensive account is given of the discovery and study of the fossil footprints of vertebrates in the British Isles. Brief summaries are given of work published in journals that are generally available to the geologist at large; however, since many papers were published in obscure books and journals, the illustrations in these are reproduced and the papers themselves directly quoted wherever appropriate. A number of specimens important in the history of British vertebrate ichnology are illustrated for the first time; in particular, the holotype of Chelichnus ingens Binney (1856), the “Kegworth footprint” from Leicestershire, the supposed “monotreme footprint” of Seeley (1899), and the first Iguanodon footprint to be described from Sussex (Tagart, 1846). Illustrations are given for the first time of footprints from the Forest Marble of Wiltshire thought to be those collected by Scrope (1831), of a footprint from the Permian of Warwickshire, mentioned by Vernon (1912), and of a footprint from Caithness. The account is extensively supplemented by text-figures of principal footprint types and, so far as possible, the present whereabouts of figured or described specimens is indicated. (Many, unfortunately, are lost.) An exhaustive bibliography of fossil vertebrate footprints from the British Isles is presented. Particular attention is paid to the important discoveries in the Cheshire Basin by the amateur geologists of the Liverpool region. An account of the work of Henry C. Beasley (1836–1919), the most eminent British worker in this field, is given for the first time; his portrait, and photographs relating to his work in the Storeton quarries, are published for the first time. The stratigraphical and palaeoecological significance of the footprints is assessed wherever possible and reasons are presented why a more extensive resumption of work in this field is desirable.

The paper describes Late Jurassic–Early Cretaceous seep carbonate boulders from the Russian Arctic island of Novaya Zemlya, collected in 1875 by A.E. Nordenskiold during his expedition to Siberia. The carbonates are significantly depleted in heavy carbon isotopes (δ13C values as low as ca. − 40‰) and show textures typical for carbonates formed under the influence of hydrocarbons, such as fibrous carbonate cements and corrosion cavities. The rocks contain index fossils of Late Oxfordian–Early Kimmeridgian, Late Tithonian (Jurassic) and latest Berriasian–Early Valanginian (Cretaceous) age. The fossil fauna is species rich and dominated by molluscs, with subordinate brachiopods, echinoderms, foraminifera, serpulids and ostracods. Most of the species, including two chemosymbiotic bivalve species, likely belong to the ‘background’ fauna. Only a species of a hokkaidoconchid gastropod, and a possible abyssochrysoid gastropod, can be interpreted as restricted to the seep environment. Other seep faunas with similar taxonomic structure are suggestive of rather shallow water settings, but in case of Novaya Zemlya seep faunas such structure might result also from high northern latitude.

Two new 40Ar/39Ar ages (*) and previously published K/Ar ages of basaltic pillow lava flows are coeval with closely-related fossiliferous marine layers, allowing us to establish the beginning (5.8; 5.0; 4.8 Ma at Ajui, Fuerteventura Island and 4.8 ± 0.03 Ma (2σ)* at Tamaraceite) and a middle stage (4.20 ± 0.18 Ma (2σ)* at La Esfinge in Gran Canaria Island) of Early Pliocene marine deposits in the Canary Islands. Here the presence of tropicopolitan fossils (Megaselachus megalodon, Janthina typica) suggests the influence of a possible Central American Circumtropical Current during the Pliocene and in the North Atlantic basin. The presence of both Janthina typica and the Argonauta argo also indicate the occurrence of tropical storms in the area of the Canary Islands around that time. In addition, the pillow lava flow at La Esfinge overlies a submarine pyroclastic layer containing Ostrea offreti that was preserved in its life position, a fossil from the terminal Miocene and commonly found on the south eastern Iberian Peninsula. At La Cruz on Fuerteventura Island, a dune formed above marine deposits lies beneath a palaeosol and a basaltic lava flow that was K/Ar dated at 2.9 Ma. Near El Marmol in Gran Canaria the corresponding palaeosol lies between lava flows K/Ar dated at 3 Ma. Based on these observations, we argue in this paper that the first appearance of the Canary Current, the eastern boundary current of the North Atlantic sub-tropical gyre, occurred between 4.2 Ma and 2.9 Ma ago. This was followed by a major sea level drop (of about 40 m) and the formation of a first fossil-bearing palaeosol which indicate that major climate change that took place around 2.95–2.82 Ma.

The present study consists of the microscopic and geochemical analyses of specimens of the trace fossil Phymatoderma from the Pliocene deep-marine strata (Shiramazu Formation, Japan). The aim of this paper is to assess whether benthic-pelagic coupling functioned in the ancient ocean as it does in the modern ocean. Various types of microfossils (e.g., coccoliths, diatoms, planktonic foraminifera, and radiolaria) were detected by SEM observation of fecal pellets of Phymatoderma. Among these plankton, coccolithophores are considered to have been the most important dietary source for the Phymatoderma-producing echiuran worm, because excreted tuffaceous fecal pellets are occasionally found to be composed exclusively of coccoliths. Elemental analysis using the SEM-EDS system revealed that CaO, which is probably derived from the microfossils of calcareous plankton (i.e., coccoliths and planktonic foraminifera), was abundant in the tuffaceous fecal pellets. Considering the obtained microscopic and geochemical evidence, it is most likely that the echiurans’ deposit-feeding activity was synchronized with an episodic (probably seasonal) coccolithophore bloom deposition on the deep-sea floor. Such a mode of feeding may have facilitated the effective uptake of freshly deposited phytodetritus. The present study provides geologic evidence for benthic-pelagic coupling in the Pliocene Epoch. In addition, based on the integration of the obtained results and reinterpretations of the existing data, the present study further supports the possibility that the modern-type benthic-pelagic coupling had established during the Cretaceous Period.

Sea-level reconstructions based on foraminiferal assemblage data are common for temperate salt-marsh settings. In comparison, the widespread mangrove swamps of equatorial to subtropical settings have received considerably less attention due to enhanced taphonomic loss of specimens, extensive bioturbation, abundant infaunal foraminifera and irregular intertidal topography. The tropics, however, provide the best possible estimate of “eustatic function” and thus are important for testing earth-ice models. In this paper, we use foraminiferal data, in a chronologic framework provided by optically stimulated luminescence, radiocarbon and Pb-210 age estimates, to determine coastal evolution and rates of sea-level rise in the Setiu wetland of northeastern peninsular Malaysia on the western margin of the southern South China Sea over the past ca. 200 years. Foraminiferal data from three surface transects across fringing mangrove swamps were used to interpret four cores from mid to high mangrove swamp settings. Patterns of foraminiferal distribution were determined by correspondence analysis, canonical correspondence analysis and detrended canonical correspondence analysis of dead assemblage data. We used weighted averaging as the transfer function model to reconstruct sea-level curves for the cores and to provide a composite reconstruction for the last ca. 200 years. Based on one C-14 estimate, sea level rose during the 19th century at 1.26 mm yr− 1. The rate increased to 3.2 ± 0.6 mm yr− 1.around 1900 CE, roughly coincident with rate increases recorded globally. However, the 20th century rate in the Setiu wetland is considerably greater than that of global estimates (ca. 1.8 mm yr− 1) for this period. Rates of sea-level rise in the Gulf of Thailand (immediately to the north of the Setiu wetland) determined from GPS-corrected tide gauge data and multi-satellite altimetry are geographically variable but also greater than the global rate. The data from the Setiu wetland provide the first foraminifera-based sea-level reconstruction of the past few hundred years from the southeastern South China Sea (SCS) and they represent the first time the early 20th century increase in rate of sea-level rise has been identified using proxy foraminiferal data in an equatorial setting.

The accurate habitats of the extinct ammonites and belemnites are largely unknown. Most ammonites are thought to have had a pelagic lifestyle, while belemnites are often considered to have dwelled in deeper, colder waters. Stable isotope analysis (δ18O, δ13C) provides a useful method to reconstruct the habitats of these two groups of extinct cephalopods, but is at the same time limited by various unknowns, including the isotopic composition of the past seawater, ‘vital’ effects and diagenesis. In this paper, stable isotope data from 12 ammonite shells (Simbirskites spp.) from the upper Hauterivian of the Lower Saxony Basin (northwest Germany) are presented. Ontogenetic isotope profiles have been obtained from six of these shells in order to reconstruct habitat changes during their lifetime. These new ammonite data are combined with published stable isotope data from belemnites (Hibolithes jaculoides) and TEX86 palaeotemperature-estimates from the same section. The combination of isochronous ammonite and belemnite stable isotope data shows that the resulting values of both groups go along with each other. Calculated palaeotemperatures of the two groups differ by 5–10 °C, with belemnites always showing the colder temperatures. All juvenile shells show an increase of the δ13Camm to more positive values throughout their ontogeny; they are stable in an adult shell-fragment. The incorporation of carbon isotopes in the ammonite shell therefore correlates with ontogeny and is influenced by metabolic effects, probably linked to the shell growth rate. The isotope profiles further suggest vertical habitat changes during the ontogeny of the ammonites, indicating that the δ13Camm values might record a combination of environmental and metabolic signals. Taking into account studies on oxygen isotope fractionation of recent aragonitic and calcitic mollusc shells, a similar pelagic habitat is proposed here for both, ammonites and belemnites.

The Wenbudangsang section is a newly discovered continuous succession of marine carbonates that straddles the Permian–Triassic boundary (PTB), extending from the late Permian to the earliest Triassic (Induan). The section is located in the Wenbudangsang area of Geji County, northern Tibet, and tectonically sits within the northern Gangdise Stratigraphic division. Conodonts are abundant throughout this section, except being comparatively rare and less diverse in the Permian strata below the distinctive PTB Clay Bed. The conodonts are mainly represented by Hindeodus–Isarcicella Pa elements, Neogondolella Pa elements, and ramiform elements, with few Neospathodus Pa elements present at the top of the section. Two conodont zonal successions have thus been determined based on Hindeodus–Isarcicella and Neogondolella species. The Hindeodus–Isarcicella succession includes the uppermost Permian Hindeodus julfensis Zone, Hindeodus praeparvus Zone, and the lowermost Triassic Hindeodus parvus Zone, Isarcicella staeschei Zone, Isarcicella isarcica Zone, and Hindeodus postparvus Zone. The Neogondolella succession consists of the upper Permian Neogondolella changxingensis–Neogondolella deflecta–Neogondolella postwangi Zone, Neogondolella yini–Neogondolella zhangi Zone, Neogondolella meishanensis Zone, the Neogondolella taylorae Zone that crosses the PTB, and the lowermost Triassic Neogondolella krystyni Zone and Neogondolella prediscreta n. sp. Zone. The top of the section is defined by the Neospathodus kummeli Zone and Neospathodus cristagalli Zone. Two new species, Hindeodus microdentatus n. sp. and N. prediscreta n. sp., are established and described in this paper. The PTB conodont successions recognised in the new Wenbudangsang section have been closely correlated herein with other well-known PTB sections: the GSSP Meishan section of South China, sections in Abadeh in Iran, and sections at Spiti in India. Importantly, the conodont faunas from Wenbudangsang now provide an opportunity to effectively correlate the PTB hindeodid and gondolellid zonal schemes given the high abundance of both assemblages, which is unique to this section.

Paleontologists have favoured univariate statistical methods over multivariate ones, using information-rich data to derive diversity measures such as the Simpson's index. However, such palaeontological datasets may benefit from flexible multivariate methods that exploit data directly. Hence in this work, with the aim of quantifying and characterising the spatio-temporal change in the species composition and abundance of benthic foraminiferal assemblages, univariate and multivariate statistical techniques are applied on a Lusitanian Basin dataset from the Lower–Middle Jurassic transition. This paper presents the trends identified at spatial and temporal scales, i.e. among sections corresponding to distal, middle and proximal palaeogeographical positions within the platform and between two successive stratigraphic intervals (upper Toarcian and lower Aalenian). It also compares the results obtained by univariate and multivariate methods. Samples in the reference sections are composed by taxa typical of the Jurassic carbonate marine platforms of the Boreal Realm, such as Vaginulinidae and Lenticulina species. Univariate analysis only found significant change in species diversity between the two most distant sections and failed to detect any temporal change. In contrast, multivariate analysis (PERMANOVA and NMDS) revealed that spatial change in assemblage structure (22%) quadruples temporal change (5%). CAP analysis identified characteristic species for each section along the palaeogradient, with a posterior cross-validation procedure that classified correctly 97% of the samples. In fact, multivariate results suggest the existence of stable palaeoecological conditions across the Lower–Middle Jurassic transition in the Lusitanian Basin. Future work in the field may benefit from multivariate analysis, including hydrocarbon exploration activities where only core samples are available and foraminifera are currently used.

Lobopodians are an important group of organisms which appeared during the Cambrian Explosion. The underlying morphology is invariably a worm-like body bearing multiple pairs of legs. Yet in detail these animals preserve a range of morphologies and have attracted much paleontological attention; particularly since this assemblage probably includes the ancestors of living velvet worms (Onychophora), water bear (Tardigrada) and arthropods (Arthropoda). In recent years, knowledge of Cambrian lobopodians has increased dramatically based on numerous new records. However, there have been few comprehensive reviews of these animals since Ramskold & Chen's study in 1998. In the present paper, new insights into Cambrian lobopodians are presented. The legs of Aysheaia pedunculata have a strong attachment with the body, like those of lobopodians in the Chengjiang Fauna. Hallucigenia fortis has a pair of eyes, two pairs of tentacles are observed in the ‘neck’ region while a bivalved head shield is unequivocally lacking. Some new characters for, and the orientation of, Hallucigenia sparsa are discussed. Longitudinal wrinkles on the body of Xenusion auerswalde are regarded here as putative muscles. Cardiodictyon sinicum bears doublure structures at the anterior margin of head and a pair of eye spots; the shape of dorsal plates is also reinterpreted. Onychodictyon has a pair of anterior appendages, but no sclerotized head shield. The affinities of Miraluolishania haikouensis are clarified and the proposal that M. haikouensis is a junior synonym of Luolishania longicruris is refuted. The large lobopodians, Kerygmachela, Jianshanopodia and Megadictyon – all with frontal appendages, gill-like limbs and tree-like or lamellate-like branches – may be swimming predators.

The occurrence of crowded Rosselia ichnofabric in Early Devonian deposits of ‘Transition Beds’ (Western Gondwana Parana Basin, southern Brazil) and the paleobiology and paleoecology of its potential tracemakers are discussed in this paper. Crowded Rosselia ichnofabric has been recorded chiefly in Cenozoic storm beds associated with high sedimentation rates on the inner shelf, and is usually interpreted as resulting from opportunistic behavior of terebellid polychaetes. Rosselia is a common ichnotaxon in the archetypical Cruziana ichnofacies, developed preferentially in fair-weather deposits formed in inner shelf settings. During storm surges, however, this endobenthic community is strongly affected, decimating those that are unable to escape. New records presented herein reinforce the conclusion that short-term colonization represented by crowded Rosselia ichnofabric occurs essentially in erosive storm deposits of high sedimentation rates. Rather than being opportunistic, the crowded Rosselia ichnofabric appears to be the result of a strategic behavior developed by stress-tolerant terebellid polychaetes in inner shelf zones during or just after storm surges. This strategic behavior appeared during the early Paleozoic and was adopted by terebellids from their earliest appearance.

The ability to discriminate between open vegetation and closed forest in the fossil record is constrained by a paucity of suitable proxies. Taxonomy-based proxies (especially the floristic composition of fossil pollen assemblages) provide the main tool for inferring vegetation type but this approach can be confounded by evolutionary changes in ecology, especially for ancient fossil assemblages. This paper considers a range of indicators of open vegetation that can be observed on fossil leaves. We show that the presence of amphistomatic leaves (i.e. leaves with stomata on both upper and lower surfaces) is unambiguously associated with open vegetation in the ecologically diverse family Proteaceae. This linkage shows very high levels of evolutionary convergence and the relationship is not explained by climate. Similar relationships are also present in a wide range of other plant groups. The combination of these empirical correlations and physiological theory suggests that there is a strong functional link between amphistomatic leaves and open vegetation. Theory says that amphistomy increases the efficiency of water transport and gas exchange by allowing two layers of high performance photosynthetic tissue to be proximal to sources of both carbon dioxide (stomata) and water (veins). However these benefits come at the cost of requiring thick leaves, which are inefficient in shaded environments. Other leaf characteristics observable on fossils (especially very thick cuticles, the presence of thick lignified hypodermal layers and the presence of deeply encrypted stomata) may also indicate the presence of open vegetation, although the functional links between these traits and vegetation type are more indirect. We propose that amphistomatic fossil leaves of dicotyledonous angiosperms provide a strong proxy for open vegetation but any inference will be enhanced by evidence from alternative proxies. We also provide an example of the application of this proxy.

Geographically isolated insular species face energetic restrictions and commonly evolve adaptations that distinguish them from their mainland ancestors. During the Pleistocene, several Mediterranean islands were inhabited by now extinct Hippopotamidae. They underwent diverse changes in locomotion, dentition and body size. Based on these differences, it is supposed that they occupied different ecological niches depending on their respective faunal complexes and available resources. In this paper, we assess the paleoecology of dwarfed hippopotami from Crete, Malta, Sicily and Cyprus using a novel dental multiproxy approach. We applied dental topography analysis (SAGA-GIS) to measure the mean slope of the dental occlusal surface, mirroring dietary adaptations, as well as 3D surface texture analysis (3DST) to quantify the surface of occlusal wear facets, which correlate with dietary abrasiveness. Low slope values were found in the larger, more hypsodont hippopotami, whilst the smaller Phanourios minor displayed the highest occlusal relief with large compression basins. Since Hippopotamus pentlandi exhibited lower mean slope values than the larger, more hypsodont Hippopotamus amphibius, we conclude that lower occlusal reliefs reflect adaptations to lower diet quality and arid environments, which are characteristic of freshwater-limited island habitats. The 3DST analysis revealed distinct ecological niches for the investigated insular hippos. Hippopotamus creutzburgi exhibited enamel surface textures analogous to those of Hippopotamus amphibius, a fresh grass grazer, thus confirming a semiaquatic lifestyle at the upland lake at Katharo, Crete. Hippopotamus pentlandi was bound to a similar niche to the extant form, probably due to the mainland character of its fauna, but experienced more dust intake. Hippopotamus melitensis had to cope with high ingestion of abrasives, seemingly on account of a more generalistic diet in its resource-limited and small habitat. Results point to either Phanourios minor broadening its dietary niche in its almost competition-free habitat, or suggest a dietary shift following a climatic change. The adopted multiproxy approach proved to be useful in identifying dental adaptations and individual foraging strategies linked to energetically restricted habitats, and therefore contributes to a better understanding of basic evolutionary and ecological principles.

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 δ 13 C 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 δ 13 C excursion is interpreted as a record of increased rates of organic carbon burial. The δ 13 C 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.

article i nfo The Pliocene (5.3-2.6 Ma) 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 consti- tute 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 environ- mental 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 charac- teristic 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 ~400 Ka to 6.4 Ma. Within the 800-m Zanda section, the lower 0-150 m is of latest Miocene age, spanning 6.4-5.3 Ma. Sparsely fos- siliferous, the lower section has produced five taxa so far: Ochotona, Panthera, Qurliqnoria, Palaeotragus ,a nd Hipparion—all are consistent with a late Miocene age. The middle 150-620 m section spans the entire Pliocene. This section is by far the most fossiliferous, including such typical Pliocene small mammals as Prosiphneus, Mimomys, Apodemus ,a ndTrischizolagus, as well as large mammals such as Coelodonta thibetana, Hipparion zandaense, Chasmaporthetes, Nyctereutes, Meles, Antilospira, and others. In the upper 620-800 m section the fos- sils 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 ,a ndXenocyon 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 barrierby the Himalayas despite a short distance (~100 km) between Zanda Basin and the Indian subcontinent.

In this paper we present a paleoceanographic reconstruction of the southwestern South Atlantic for the past 13 kyr based on faunal and isotopic analysis of planktonic foraminifera from a high-resolution core retrieved at the South Brazil Bight continental slope. Our record indicates that oceanographic changes in the southwestern South Atlantic during the onset of the Holocene were comparable in strength to those that occurred during the Younger Dryas. Full interglacial conditions started abruptly after 8.2 kyr BP with a sharp change in faunal composition and surface hydrography (SST and SSS). Part of the observed events may be explained in terms of changes in thermohaline circulation while the other part suggests a dominant role of winds. Our data indicate that during the Early Holocene upwelling was significantly strengthened in the South Brazil Bight promoting high productivity and preventing the establishment of the typically interglacial menardiiform species. In general terms, oceanographic changes recorded by core KF02 occurred in synchrony with Antarctica's climate.

This paper reports the results of an analysis of 508 sub-fossil carpometacarpi of swiftlets (Aves: Apodidae) recovered during archaeological excavations of the Great Cave of Niah in Sarawak, North-western Borneo. The bones date from 48 ky BP (ky BP: 103 calibrated years before present [1950]) to 0.35 ky BP and provide a means to consider populations of birds (of which one species is a significant commercial interest) in the context of environmental and climatic change in the past, and their responses to recent anthropogenic landscape changes in the present. Biometric analyses and comparative data indicate that the collection contained specimens attributable to the three extant species of swiftlet that currently inhabit the Great Cave: the black-nest swiftlet (Aerodramus maximus), mossy-nest swiftlet (Aerodramus salanganus) and the white-bellied swiftlet (Collocalia esculenta). A subset of 267 identified specimens provides a time series that suggests that the Great Cave and environs have sustained populations of these three species throughout last 48,000 years. While changes in the wing length of extant species of swiftlet are known as a function of geographical and altitudinal range, statistical testing of a single character (greatest length of the carpometacarpus) did not indicate changes in wing length in any of the identified species. The findings indicate that the local environs maintained a sufficient abundance of aerial arthropods to support populations of these obligate insectivores and are consistent with studies that suggest that the structural diversity of forest habitats was maintained throughout the late Pleistocene (48 ky BP to 11.6 ky BP) and Holocene (11.6 ky BP to 0.35 ky BP). The findings also provide context for the recent declines of the commercially-significant black-nest swiftlet and suggest that this species may be ill-equipped to adapt to recent anthropogenic deforestation of the Niah area.

This paper presents a stratigraphical and geomorphological analysis supported with geochronological dating aiming to reconstruct the Late Holocene lake-level fluctuations and paleohydrological history of Lake Hayk. This lake (23 km2 in surface) is located in the eastern side of the northern Ethiopia highlands, at an altitude of around 2000 m above sea level. Along the northern margin of the lake, which is mainly characterized by steep rocky slopes, the studied succession consists of colluvial and stromatolitic deposits. Along the southern margin, which is characterized by a wide coastal plain drained by the main watercourse feeding the lake (the Ankarka River), the study deposits are mainly palustrine, deltaic and fluvial in origin. Geomorphological and sedimentological data, integrated with a radiocarbon chronology, highlighted that during the last 3500 years the lake was affected by three main highstand phases, which occurred at about 3250–3000, 2600–950 and 650–160 cal yrs BP, respectively. These highstands are documented by aggradation of siliciclastic systems both along the southern and northern margins, whereas isotope data highlight that most of the stromatolitic deposits developed during phases of intense evaporation. This peculiar feature could be differently explained: i) stromatolite growth was triggered by rapid lacustrine rises, but mainly occurred during the long-lasting lacustrine falls; ii) stromatolite developed during tectonic-induced transgressions, which occurred during phases of intense evaporation. Despite the possible effects of local tectonics, the Lake Hayk record shows a good correlation with those of several late Holocene lakes of East Africa lakes (Naivasha, Tanganyika, Victoria, Turkana, Abhe, Ziway-Shala, Bosumtwi and Abyiata), highlighting that it can be considered as a suitable climatic proxy for late Holocene time span. In particular, by both siliciclastic and stromatolitic deposits occurring in the uppermost part of the sedimentary succession record high-frequency oscillations, which have been ascribed to three main droughts that occurred during the Little Ice Age. These droughts were previously documented only in Lake Naivasha and Lake Victoria.

The tectonic evolution of the Qiangtang Block in the Qinghai–Tibetan Plateau has been a controversial subject for a long time. In this paper, the discovery of new stratigraphic and fusuline fossil evidence from the Permian sequences (Qudi and Lugu formations) of the Qiangtang Block is reported and the palaeogeographical position and tectonic history of this block during the Late Cisuralian (Late Early Permian) are discussed. The Qudi Formation is typified by thick turbidite deposits and contains Artinskian fusulines such as Pseudofusulina and Chalaroschwagerina . The fusulines were deposited as grains involved in debris flow deposits, suggesting a synchronicity with the depositional time of the turbidites. The subsequent Lugu Formation is dominated by seamount-type carbonates with an irregular basalt base. Fusulines Cancellina , Pseudodoliolina and Parafusulina in the base of the carbonates confirm its age as middle Kungurian. The transition from the turbidite Qudi Formation to the seamount Lugu Formation is here interpreted to be a continuous depositional process recording the Qiangtang Block's separation from the Indian Plate. This separation signaled the opening of the Neotethys Ocean between the Qiangtang Block and the Indian Plate. Palaeogeographically, the Qiangtang Block's separation is comparable with the Baoshan Block's separation in the east and Central Pamir's separation in the west. By contrast, the ultimate opening of the Neotethys Ocean by the separation of India–Pakistan and northern Oman is apparently much later than this event recorded in the Qiangtang Block. Consequently, it is interpreted that the opening of the Neotethys Ocean in the whole northern Gondwanan margin is a diachronous series of events.

This paper presents the first quantitative study of the Early Jurassic recovery of ammonoids after the end-Triassic mass extinction based on detailed U–Pb ID-TIMS (isotope dilution thermal ionization mass spectrometry) geochronology from ash bed zircons placed within a clear phylogenetical and biochronological framework at the subzonal and species level. This study was triggered by the discovery of a rich Peruvian succession of ammonites, deposited concomitantly with an unusually large number of ash beds. Two major phases of rediversification are observed during the Psiloceras spelae and Angulaticeras zones that correspond to positive peaks in the δ13Corg curve, providing a possible link between biodiversity and the global carbon cycle. In the case of the post-extinction recovery, the development of the earliest Hettangian ammonites occurs within the genus Psiloceras, which begins with the occurrence of P. spelae and then explodes into worldwide development of smooth psiloceratids of the Psiloceras planorbis group s.l. This rapid biodiversification likely occurred less than 100 ka after the end-Triassic crisis; the genus Psiloceras occupied all the possible ecological niches worldwide, from the Pacific deep waters to the NW European shallow deposits and also in some rare Tethyan occurrences like at Germig in Tibet. This global dispersion allowed the differentiation of the group in several major phyla, the Schlotheimiidae, Discamphiceratinae, Arietitidae and Lytocerataceae, which were the roots of all other Jurassic and Cretaceous ammonites.

Long-term evolution is thought to take opportunities that arise as a consequence of mass extinction (as argued, for example, by Gould, 2002) and the following biotic recovery, but there is absolutely no evidence for this being the case. However, our study shows that eutrophication by oceanic mixing also played a part in the enhancement of several evolutionary events amongst marine organisms, and these results could indicate that the rates of oceanic biodiversification may be slowed if upwelling becomes weakened by future global warming. This paper defines three distinct evolutionary events of resting spores of the marine diatom genus Chaetoceros, to reconstruct past upwelling through the analysis of several DSDP, ODP and land-based successions from the North, South and equatorial Pacific as well as the Atlantic Ocean during the past 40 million years. The Atlantic Chaetoceros Explosion (ACE) event occurred across the E/O boundary in the North Atlantic, and is characterized by resting spore diversification that occurred as a consequence of the onset of upwelling following changes in thermohaline circulation through global cooling in the early Oligocene. Pacific Chaetoceros Explosion events-1 and -2 (PACE-1 and PACE-2) are characterized by relatively higher occurrences of iron input following the Himalayan uplift and aridification at 8.5 Ma and ca. 2.5 Ma in the North Pacific region. These events not only enhanced the diversification and increased abundance of primary producers, including that of Chaetoceros, other diatoms and seaweeds, but also stimulated the evolution of zooplankton and larger predators, such as copepods and marine mammals, which ate these phytoplankton and plants. Current thinking suggests new evolutionary niches open up after a mass extinction, but our study finds that eutrophication can also stimulate evolutionary diversification. Moreover, in the opposite fashion, our results show that as thermohaline circulation abates, global warming progresses and the ocean surface becomes warmer, many marine organisms will be affected by the environmental degradation.

The limits of the distribution of closed canopy forest in Southeast Asia during the glacial cycles of the Pleistocene are the subject of continuing debate. In this context, this paper reports the results of an analysis of a novel line of evidence as a local scale case study. 22 dated assemblages of bat bones that were recovered from the archaeological sequences of the Great Cave of Niah in Sarawak, Malaysian Borneo were examined. By examination of the morphological characteristics of the distal articulation of the humerus, seven families and nine genera were identified. Five species level attributions could be made. These assemblages formed a time series of 14 chronological intervals 48–0.35 ky BP (ky BP: 103 calibrated years before present [1950]) incorporating samples from the high glacial interval (26–18 ky BP) and Last Glacial Maximum (23–19 ky BP). Bones of bat taxa that are adapted to forage in the cluttered environments in the interior of closed canopy forest (“Strategy I” bats) were employed as proxy evidence for the presence of closed canopy forested habitats in the vicinity ( Bones of Strategy I bats (principally small Hipposideros spp.) were identified in all examined assemblages and intervals in the time series. Statistical testing indicated no evidence of differences in the absolute frequency of distal humeri from Strategy I bats in the Pleistocene samples 48–11.8 ky BP, or in the entire time series 48–0.35 ky BP and no significant linear trend was found in the time series to suggest an increase of the bones Strategy I bat taxa with the onset of the Holocene. These findings suggest that closed canopy forest habitats have been a persistent component in the landscape around the Great Cave of Niah since 48 ky BP. A taphonomic hypothesis is proposed to explain the dichotomy between the findings of this study and the pollen record of the site.

In this paper, we present a chronostratigraphic calibration of the shallow benthic zones (SBZs) of larger foraminifera during Lutetian times based on new magnetostratigraphic data (Isuela section) and two new densely sampled biostratigraphic sections (Isuela and Gabardiella). These sections are located in the External Sierras (Southern Pyrenees) and represent an ideal location to avoid previous chronostratigraphic problems. 1) They belong to a shallow carbonate shelf environment with abundant larger foraminifera, which ensure the reliability of SBZ data. 2) The time span covers almost the entire Lutetian interval. 3) The profiles are sufficiently long to establish trustworthy local scales, both the SBZs (520 m and 760 m in Isuela and Gabardiella respectively) and the paleomagnetic local polarity sequence (LPS) (520 m). 4) The excellent outcropping conditions also permit a detailed paleomagnetic and biostratigraphic sampling to be performed. The LPS at the Isuela section was built after sampling every 2.6 m. In total, more than 359 samples were thermal (244) and alternating field (115) demagnetized. Characteristic remanent magnetization (ChRM) usually dropped at 560 °C. Only 43% the samples (359 demagnetizations) gave reliable directions (high quality) for the LPS. A further short section (Gas line) was also cored (38 samples in 90 m) to obtain more detailed data for the upper part of the section. At the Isuela section, the results allow three pairs of trustable magnetozones to be assembled within the Lutetian. A further 255 samples were taken for biostratigraphic purposes, 55 sites at the Isuela and 52 at the Gabardiella sections being determinant. This density enabled a thorough study of changes in fossil associations to be performed. Assuming a constant accumulation rate within the chron boundaries, absolute ages have been estimated for the biostratigraphic boundaries. Combining all these data allows the previous calibration of SBZ during Lutetian times in the geological time scale to be refined. In particular, with this new data, we identify the SBZ 13/SBZ 14 boundary at 44.46 Ma reaching C20r; a boundary interval spanning from SBZ 14 to SBZ 15 (41.36 and 42.45 Ma) is found within C20n and C19n; and, finally, the top of SBZ 15 can be accurately located at 41.12 Ma (C19r), Unidad de Zaragoza, Instituto Geológico y Minero de España, España, Departamento de Ciencias de la Tierra, Universidad de Zaragoza, España, Departament d'Estratigrafia, Paleontologia i Geociències Marines, Universitat de Barcelona, España, Consultant Geologists, Unidad de Tres Cantos, Instituto Geológico y Minero de España, España

In northeastern Siberia, Russia, a 1.2 m sediment core was retrieved and radiocarbon dated from a small and shallow lake located at the western side of the lower Lena River (N 69°24′, E 123°50′, 81 m a.s.l.). The objective of this paper is to reconstruct the palaeoenvironmental variability and to infer major palaeoclimate trends that have occurred since ~ 13.3 cal. kyr BP. We analysed the diatom assemblages, sedimentology (grain-size, total organic carbon (TOC), total nitrogen (TN)), and the elemental and mineralogical composition using X-ray fluorescence (XRF) and X-ray diffractometry (XRD) of the sediment core. Our results show parallel changes in the diatom species composition and sediment characteristics. Enhanced minerogenic sediment input and the occurrence of pyrite is indicative of a cold period between ~ 12.7 and 11.6 cal. kyr BP. The diatom data enable a qualitative inference about the local ecological conditions to be made, and reveal an oligotrophic lake system with alkaline and cold conditions during the earliest Holocene. Moderately warmer climates are inferred for the period from ~ 9.1 to 5.7 cal. kyr BP. The major shift in the diatom assemblage, from dominance of small benthic fragilarioid taxa to a more complex diatom flora with an influx of several achnanthoid and naviculoid diatom species, occurred after a transitional period of about 1400 yr (7.1 to 5.7 cal. kyr BP) at ~ 5.7 cal. kyr BP, indicating a circumneutral and warmer hydrological regime during the Holocene thermal maximum (HTM). Diatom valve concentrations declined starting ~ 2.8 cal. kyr BP, but have been rising again since ≤ 600 cal. yr BP. This has occurred in parallel to the increased presence of acidophilous diatom taxa (e.g. Eunotia spp.) and decreased presence of small benthic fragilarioid species in the most recent sediments, which is interpreted as the result of neoglacial cooling and subsequent recent climate warming. Our findings are compared to other lake-inferred climate reconstructions along the Lena River. We conclude that the timing and spatial variability of the HTM in the lower Lena River area reveal a temporal delay from north to south.

The ability to correlate with high precision among geological successions is critical in evaluating the global coincidence and therefore magnitude and duration of geological events. This is a difficult problem given resolution uncertainties and ambiguities in biostratigraphic data sets. The magnetostratigraphy susceptibility (MSS) method, based on low-field bulk magnetic susceptibility (MS) measurements of closely spaced samples, provides a well-established, abiotic, high-resolution correlation tool in stratigraphy, that when combined with bio-, chemostratigraphic, and other geophysical techniques, offers ways to resolve correlation problems. In addition, such data sets lend themselves to time-series analysis, where developing high-resolution timing of events becomes possible. This paper examines the final episode (equivalent to the Geneseo Bioevent in the Appalachian Basin) of the important Taghanic Biocrisis known from globally distributed Middle Devonian geological sections. The Geneseo Bioevent is important because the extinction of some major fossil groups occurred during this time, while other groups declined significantly, including many benthonic groups. However, the maxima of extinctions does not appear to have occurred everywhere simultaneously. To help resolve timing of this bioevent, results are reported for two Middle Devonian successions from Northern Spain, the S. Huergas de Gordon and Punta Boletos sections, both showing the final Taghanic Biocrisis, Geneseo interval, and correlate these successions to the same interval within an independent, global database. Time-series analyses of the MSS data sets from the Spanish sections was performed using Multi-Taper (MTM) and Fourier Transform (FT) methods, and have extracted well-defined Milankovitch bands from the primary MS data from each section. Using FT and MTM values for eccentricity at ~ 400 kyr and ~ 100 kyr, a floating-point time scale was developed for the two Spanish sections that provides age resolution to ~ 50 kyr for these successions. The results show that the Geneseo Bioevent in Northern Spain occurred within a narrow time window estimated to have lasted for ~ 70 kyr. This time window fall s within the Polygnathus ansatus (uppermost part)–Ozarkodina semialternans conodont zones, just at the Middle–Upper Givetian boundary of the Middle Devonian in what appears to be the upper, regressive phase of T–R cycle IIa.

The Triassic is bounded by two of the most severe biotic crises, but nevertheless this time was, for bivalves, both a recovery and a diversification period, and a moment to fully exploit some of their evolutionary novelties. Just how and when this was achieved is analyzed in this paper, which covers Induan to Sinemurian bivalve diversity, based on a newly compiled database. Taxonomic diversity and ecospace dynamics are examined separately. Diversity and evolutionary rates were assessed, extinction selectivity was tested using a resampling algorithm, and cohort analysis was used to study extinction patterns. During the Early Triassic most bivalve genera were survivors from the Permian and they were mainly cosmopolitan epifaunal and semi-infaunal endobyssate taxa. Reclined, epifaunal and semi-infaunal bivalves increased in diversity during the Triassic, but from Norian on, their diversity declined, and they were strongly affected by the T/J crisis. Although the Triassic/Jurassic extinction strongly impacted bivalve taxonomic diversity, it had little impact on bivalve ecologic diversity. Not a single bivalve life strategy was eliminated at the end of the Triassic. The present study does not support previous conclusions that infaunal bivalves suffered greater extinction than epifaunal ones during the T/J extinction. Not all life strategies were equally affected by the extinction event, being the deep infaunal burrowers positively selected. Bivalves with major energetic requirements seem to have been more affected with negative selectivity on fast shallow burrowers. The ecologic diversity changes of bivalves during the Late Triassic and several adaptations of durophagous predators reflect the effects of increasing predation pressure and support a Late Triassic origin of the Mesozoic Marine Revolution. Fil: Ros, Sonia. Universidad de Valencia; España Fil: De Renzi, Miquel. Universidad de Valencia; España Fil: Damborenea, Susana Ester. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata; Argentina. Universidad Nacional de La Plata. Facultad de Ciencias Naturales y Museo. Departamento de Paleontología Invertebrados; Argentina Fil: Márquez Aliaga, Ana. Universidad de Valencia; España

The Miocene vegetation and climate history of western China remains unclear. However, widely-distributed Miocene sediments of the Tianshui Basin in the NE Tibetan Plateau provide a great potential for deciphering the Miocene vegetation and climate history of this region. This paper presents first sporopollen record from these sediments, covering the period from 17.1 to 6.1 Ma. Sporopollen data reveal that temperate, warm-temperate broad-leaved forest of Quercus, Ulmus and Betula dominated the Tianshui region between 17.1 and 14.7 Ma, which was replaced by forest or forest-steppe of Ulmus, Artemisia and Betula between 14.7 and 11.7 Ma. After a return to a broad-leaved forest of Betula and Quercus during 11.7–8.5 Ma, the forest decreased rapidly and was replaced mostly by steppe vegetation (mainly composed of Artemisia, Chenopodiaceae and Poaceae) after 8.5 Ma. We interpret the observed vegetation changes as a result of global climate change, which is characterized by global cooling, development of Arctic ice-sheets and permanent El Nino state after the Middle Miocene Climatic Optimum. The rapid development of steppe at about 8.5 Ma suggested a permanent drying of the Asian interior at this time, coinciding with the onset of the well-known Hipparion red clay deposition in North China.

Long-term high-resolution climate proxies are essential for understanding climate variability on the Tibetan Plateau (TP), where few long-term climate records are available. In this paper, we describe a summer (August) temperature reconstruction over the period 1385-2002 based on a tree-ring width chronology of Balfour spruce (Picea likiangensis var. balfouriana) on the southeastern TP created using the Regional Curve Standardization method. The reconstruction explains 44.7% of the variance in the instrumental temperature records during the calibration period (1962-2002), and captures temperature variability over a broad region of the TP. Warmer than average Augusts were found during the periods 1446-1494, 1509-1522, 1553-1567, 1797-1812, 1845-1905 and 1918-2002. Cooler than average Augusts occurred from 1385-1416, 1426-1445, 1495-1508, 1523-1552, 1568-1686, 1695-1718, 1725-1796, 1813-1844 and 1906-1917. A warming trend in the 20th century was unprecedented during the past six centuries. The reconstruction closely matched other tree-ring summer temperature reconstructions from neighboring regions, as well as patterns from ice-core delta(18)O data, and fluctuated in synchrony with Northern Hemisphere temperature reconstructions. (C) 2011 Elsevier B.V. All rights reserved.

A middle Tournaisian flora comprising several taxa of arborescent lignophytes is documented for the first time in Australia. It challenges earlier hypotheses considering that the early Mississippian vegetation of Australia was impoverished and dominated by small to medium sized arborescent lycopsids until the Serpukhovian when climatic conditions became favorable to the thriving of the famous lignophyte-dominated “ Rhacopteris flora” recorded in Australia but also South America. The present account is based on anatomically preserved fragments of trunks and branches from two localities of Queensland, in the Broken River Province and the Burdekin Basin. Three taxa are recognized, Dameria hueberi gen. et sp. nov., the putative progymnosperm species Protopitys buchiana Goeppert 1850, and a taxon of uncertain affinities characterized by a Pitus type of wood but which differs from the latter genus by anatomical traits relative to its primary body. The possible occurrence of subtle growth rings in some of the woods from the Burdekin Basin and the conifer like traits of the Dameria wood are interpreted as ecological clues suggesting that these trees may have inhabited drier settings than the wetland habitats generally inferred for the lycopsids. This difference in habitats is suggested to explain the rarity of arborescent lignophytes compared to lycopsids in the Australian record of plants of early Mississippian age. The three taxa reported in this paper represent the earliest record of arborescent lignophytes in Australia after the global events that affected the vegetation at the Devonian–Carboniferous boundary and the extinction of Archaeopteris . They show that the successional pattern of arborescent lignophytes around the Devonian–Carboniferous boundary is comparable to that observed in Western Europe with the evidence of a diversification occurring as early as the middle Tournaisian. The palaeogeographic and stratigraphic distribution of Protopitys and Dameria indicates the occurrence of extensive floral exchanges between southern Laurussia and north-eastern Gondwana in the Late Devonian to Mississippian.

Sauropod dinosaurs reached their acme in abundance and diversity in North America during the Late Jurassic. Persisting in lesser numbers into the Early Cretaceous, sauropods disappeared from the North American fossil record from the Cenomanian until the Campanian or Maastrichtian stage of the Late Cretaceous. This ca. 25–30 million-year long sauropod hiatus has been attributed to either a true extinction, perhaps due to competition with ornithischian dinosaurs, or a false extinction, due to non-preservation of sediments bearing sauropods. The duration of the sauropod hiatus remains in question due to uncertainty in the ages and affinities of the specimens bounding the observed gap. In this paper, we re-examine the phylogenetic affinity of materials from Campanian-aged sediments of Adobe Canyon, Arizona that currently mark the end of the sauropod hiatus. Based on the original description of those remains and new specimens from the same formation, we conclude that the Adobe Canyon vertebrae do not pertain to titanosaurs, but to hadrosaurid dinosaurs. Other reports of Campanian North American titanosaurs are imprecisely or erroneously dated and/or identified. Based on this reassessment, the sauropod hiatus extended until the last 5 million years of the Cretaceous. Reintroduction of sauropods into North America in the Maastrichtian is first registered ca. 30 million years after the first recorded dispersals of dinosaur taxa between the continent and Asia (e.g., ceratopsians, pachycephalosaurids, theropods), but is nearly coincident with the dispersal of derived hadrosaurids to South America.

Effective wildlife management needs historical data on herbivore abundance and its interactions with vegetation, climate and disturbance over longer time periods that is available through observational and archive data. Spores specific to herbivore dung provide a potential source of information on past herbivore abundances. This paper sets out to evaluate the potential of fungal spores as environmental indicators and in particular the use of coprophilous fungi in understanding past herbivore densities and their impact on the savanna landscape of Kruger and Limpopo National Parks (South Africa and Mozambique). Spore assemblages from six sedimentary cores are analysed and compared with the pollen data. Spores of coprophilous fungi, Coniochaeta cf ligniaria, and Sordariaceae in particular provide a valuable source of information about past herbivore densities. The spore assemblages of investigated localities show historical fluctuations in herbivore abundance. Peaks in wild/domestic herbivore densities can be seen, on a local scale from 800 to 900 AD and another at 1400 AD, however, these cannot be linked with any significant changes in vegetation. The last 200–300 years have seen an increased abundance of herbivores in the Limpopo floodplain sites, particularly domestic cattle. There is no clear correspondence between changes in herbivore abundance and local vegetation in this period or the 20th century. However, domestic cattle, together with wild herbivores, probably contributed to creating a mosaic type of landscape with heterogeneous tree cover.

The present paper provides new petrographic and geochemical insights into the tectonic and depositional environment of the Late Cretaceous volcaniclastic deposits from the Hateg Basin, in the South Carpathians. These deposits are widespread in the Rachitova–Stei unit, which is tectonically delimitated from the South Carpathians' geological background by strike-slip faults. The conducted petrographic studies have revealed that the volcaniclastic rocks from the Rachitova–Stei unit are mainly pyroclastic (i.e. coarse tuffs, tuff-breccia and tuffites), with a wide variety of volcanic pyroclastic fragments, most commonly including andesites (amphibole andesites, biotite-bearing-amphibole andesites, pyroxene-bearing-amphibole andesites, pyroxene-andesites), and less frequently latite-andesites, latites, rhyolites and dacites. The rhyolites are found only in the lower sequence of the Rachitova–Stei unit. The volcaniclastic deposits were altered by diagenetic processes. The celadonite is the most common diagenetic mineral formed in these rocks, whose presence indicates that the pyroclastic fragments have interacted with sea water. The high percentage of pyroclastic fragments with mainly angular forms and the rich-hornblende content evidence a highly explosive volcanism. The poorly-sorted pyroclastic assemblages with larger blocks and with little reworked pyroclastic material indicate a very short distance of transportation and a deposition relatively close to the explosion centre. The huge quantity of pyroclastic material from the Rachitova–Stei unit suggests that the volcanic explosion had a centre of considerable dimensions, but there is no evidence of such a volcano neither in the Hateg Basin nor anywhere else in the South Carpathians. The whole-rock geochemical composition and the immobile trace element signature from the pyroclastic fragments indicate an island arc depositional environment that was placed close to an active continental margin. In addition, the andesitic nature of the pyroclasts indicates that the volcaniclastic rocks were most probably derived from a magma generated by the subduction of an oceanic plate under a thin continental plate. The presence of the non-volcanic pyroclasts (i.e. granites, quartz-muscovite schists, muscovite quartzites, graphitic phyllites etc.), detached from the continental crust by explosion, confirms that the overriding plate is of continental material. The presence of the rhyolitic magma in the first stage of eruption also supports the continental nature of the overriding plate, the magma having resulted by the partial melting of the rocks from the continental crust. The petrographic and geochemical data have evidenced that the volcanism took place on a thin continental crust. However, this crust is not characteristic to the Getic Unit from the South Carpathians, which is commonly accepted to represent the basement of the Hateg Basin. Most probably, the volcanism was generated in another geotectonic context, respectively, in a continental island arc with a thin overriding crust, most likely situated at a lower latitude. The volcaniclastic units of the Hateg Basin were displaced and moved from this tectonic context to the present location by strike-slip movements.

Research on the uppermost Cretaceous continental deposits with dinosaur remains from the Haţeg Basin has behind it a history of more than 110 years. The first studies were by Franz Nopcsa (1877–1933) who published between 1897 and 1929 a series of notes and papers on this fauna, including five monographs dedicated to the Haţeg dinosaurs. Nopcsa described 10 vertebrate taxa, including dinosaurs, crocodilians and turtles, from the Haţeg Basin, out of which 6 are still valid. He recognized the primitiveness and the small size of most of the taxa from the Haţeg palaeofauna, characters that he related to the isolated island environment within which this fauna lived for a long time span. After Nopcsa, systematic research on the Haţeg fauna was interrupted for many decades, being resumed after 1977 when D. Grigorescu, leading a small group of students in Geology started to explore the deposits outcropping along the Sibisel valley, near Sânpetru village, from where Nopcsa made most of his collection of fossil bones. Since then the fieldwork continued every summer until now, numerous remains of dinosaurs, crocodiles and turtles being unearthed. The list of the Maastrichtian fauna from Haţeg currently includes 56 taxa from all vertebrate classes. More than half of the recorded taxa were discovered in micropalaeontological samples through screen-washing. The most spectacular discoveries made after 1977 include a large variety of small theropods, several sites with dinosaur egg clutches, one of these also yielding hatchling remains, one of the largest pterosaurs in the world, representing a new genus and species, Hatzegopteryx thambema, and several taxa of multituberculate mammals. Studies of the Haţeg fauna were not restricted to systematic palaeontology, but also covered all the fields that contribute together to an accurate reconstruction of the environment within which the Maastrichtian fauna existed. This overview includes a list of contributors to the actual knowledge on the Haţeg fauna, during the last 30 years, divided by fields of scientific interest.

The site of El Portalon is the entrance to the Cueva Mayor karst system, located in the Sierra de Atapuerca (Burgos, Spain). This is an important Holocene archaeological site, which was excavated in the 1970s but from which little has been published. New excavations starting in 2000 have highlighted a deep stratigraphical sequence, with human occupations starting at the end of the Late Pleistocene. In this paper, we present for the first time, on the basis of the small-vertebrate assemblage, palaeoenvironmental and palaeoclimatic reconstructions of the Latest Pleistocene of the Sierra de Atapuerca, well known for its Early to Middle Pleistocene human-bearing localities. The small vertebrates of El Portalon comprise at least 25 species: 4 amphibians (Alytes obstetricans, Bufo bufo, Bufo calamita and Rana temporaria); 3 squamates (an indeterminate small-size lacertid, an indeterminate large colubrine and Vipera sp.); 6 insectivores (Sorex gr. coronatus-araneus, Sorex minutus, Neomys fodiens, Neomys anomalus, Talpa europaea and Galemys pyrenaicus); 2 bats (Myotis myotis and Myotis gr. myotis-blythi); 10 rodents (Microtus arvalis, Microtus agrestis, Microtus oeconomus, Iberomys cabrerae, Chionomys nivalis, Terricola duodecimcostatus, Arvicola sapidus, Arvicola terrestris, Apodemus sylvaticus and Eliomys quercinus). These taxa, many of which are ecothermal (sensitive to temperature) show variations in their taxonomic diversity throughout the sequence. Although, with the exception of M. oeconomus, they do not differ from the extant fauna of the Iberian Peninsula, they do so in the abundance of their taxonomic assemblage. When the small vertebrates are grouped and studied in terms of vertical trends through the sequence, it is possible to follow environmental and climatic changes. Results from the small-vertebrate associations indicate that the landscape had open habitats in the vicinity of the Atapuerca caves throughout the sequence, with wet locales in the surrounding area. Woodland and water stream meadows were more developed during “warm” periods (Is5, Is6/Is7 and Is3/Is4), whereas during “cold” periods (H3 and LGM) the environment was slightly more humid in response to winter precipitation and the opening of the landscape. These results are compared with pollen analysis and marine isotopic curves, giving a scenario for the palaeoclimatic and palaeoenvironmental changes that occurred during the Latest Pleistocene in the Sierra de Atapuerca.

The classical descriptions of Middle Triassic marine Placodus gigas Agassiz, 1833 (Reptilia) from the Germanic Basin of central Europe as being shell-crushing durophagous placodontids are revised in this paper through analyses in convergent anatomy. In particular, the jaw morphologies of three placodontid genera, Paraplacodus , Placodus and Cyamodus , are compared to those of dugongs (Mammalia) such as the central European Tertiary Halitherium schinzii and the modern Dugong dugon of the Arabian Gulf. The anatomies of Paraplacodus , Placodus and Cyamodus exhibit convergences to Halitherium and Dugong . Whereas mammalian dugongs developed pachyostotic thoracic ribs to enhance their body weight, the placodontid reptiles achieved a similar result in different ways: Paraplacodus developed enlarged thoracic ribs; Placodus had pachyostotic gastral ribs, and Cyamodus had a thoracic osteoderm shield. The teeth of the placodontids are also convergent with those of Halitherium and Dugong in their general function and jaw morphology. Whereas Halitherium and the modern Dugong possess a horny oral pad and counterpart, and a specialized rasp-like tongue with which to grind the seagrass and its roots, placodontids had large teeth that covered the whole of their upper and lower jaws forming a similar crushing or grinding pad. Both of the extinct groups must have fed on sea-plants, as does the modern Dugong , although Halitherium possibly fed on both seagrass and macroalgae. A study of the wear stages of many Placodus teeth, skulls and jaws has revealed a large proportion of highly worn anterior teeth, indicating a usage similar to that of the procumbent front teeth of modern Dugong which are used to scrape plant roots from the sea-floor. In contrast, highly worn (wear stage 3) teeth are rare (0.5%) amongst all other upper palatal, maxillary, or lower-jaw dentary teeth, suggesting a relatively soft diet. Placodus must have used their broadly spaced anterior teeth, to dig macroalgae from carbonate sands in shallow marine, sand bar environments; indirect evidence for the existence of such environments is provided by the benthic communities of the Germanic Basin and the northern Tethys. Sea-plants would have been only crushed and swallowed by the placodontids and not chewed with jaw rotation, in a similar feeding strategy to that used by modern Dugong feeding on seagrass.

The extinct giant deer, Megaloceros giganteus, is among the largest and most famous of the cervids. Megaloceros remains have been uncovered across Europe and western Asia, but the highest concentrations come from Irish bogs and caves. Although Megaloceros has enjoyed a great deal of attention over the centuries, paleobiological study has focused on morphometric and distributional work until now. This paper presents quantitative data that have implications for understanding its sudden extirpation in western Europe during a period of global climate change approximately 10,600 14C years ago (ca. 12,500 calendar years BP). We report here the first stable isotope analysis of giant deer teeth, which we combine with dental cementum accretion in order to document age, diet and life-history seasonality from birth until death. Enamel ?13C and ?18O measured in the second and third molars from seven individual giant deer suggest a grass and forb-based diet supplemented with browse in a deteriorating, possibly water-stressed, environment, and a season of birth around spring/early summer. Cementum data indicate that the ages of the specimens ranged from 6.5 to 14 years and that they possessed mature antlers by autumn, similar to extant cervids. In addition, the possibility for combining these two techniques in future mammalian paleoecological studies is considered. The data presented in this study imply that Megaloceros would have indeed been vulnerable to extirpation during the terminal Pleistocene in Ireland, and this information is relevant to understanding the broader pattern of its extinction

article i nfo In South America, the arid and semiarid subtropical regions through the Atacama Desert and north-central Chile between 19° and 32°S are currently a gap in the tree-ring chronology network. Only a short tree-ring chronology has been published for this vast region and little is known about the suitability of many woody species for tree-ring analysis and dendroclimatology. In this paper we present the first detailed analysis of the climate responses and influences of the El Nino-Southern Oscillation (ENSO) and the Pacific Decadal Oscillation (PDO) on the tree-rings of three species new to dendrochronology and that typically occur at high elevations in the Andes of central and north-central Chile. Three well-replicated tree-ring chronologies of Kageneckia angustifolia, Proustia cuneifolia and Fabiana imbricata are compared with century-long regional records of precipitation and temperature, and with the N3.4 SSTand PDO indices in both time and frequency- domains using correlation and wavelet analysis. The radial growth of these species is controlled by winter precipitation and is also positively correlated with temperature during most of the rainy season from April to September (autumn-spring). The regional climate as well as tree growth is strongly modulated by ENSO and ENSO-like conditions in the equatorial Pacific at both interannual and interdecadal timescales. The decadal and interdecadal variability is not correlated with PDO and appears to be related to the Interdecadal Pacific Oscillation (IPO), a Pacific-wide ENSO-like mode of climate variability. Despite their relatively short lifespans, these three new species have a high potential for dendrochronological and dendroclimatic studies in the semiarid region of Chile over the last two centuries.