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Fossil-Lagerstätten are amongst the most important windows onto the paleobiology of ancient ecosystems. Inconsistencies surrounding what constitutes a Lagerstätte limits our ability to compare sites and thus their scientific potential. Here, we provide a modern and utilitarian classification scheme for Konservat-Lagerstätten, allowing for more consistent and improved scientific discourse. [ABSTRACT FROM AUTHOR]

In the last 5 decades, paleontological research has exploded where fossils have enabled robust dating of rocks, improved understanding of origination/extinction rates or mass extinction events, biogeography, adaptive strategies, and many more. New molecular technologies have enabled intensive analyses of vertebrates and invertebrates, plant fossils, fossilized microbes, trace fossils, and fossil molecules, alike. Paleontological research has become interdisciplinary with inputs from geology, chemistry, biology, astronomy, and archaeology. Herein, we review the principles of promising molecular technologies and explore their applications and limitations vis-à-vis paleontological research. This review will attempt to provide a roadmap that can be used for future research directions. Advanced chemical imaging provides the ability to identify and quantify chemical characteristics to evaluate taphonomic damage, original biological structures, or fossils microbes. Molecular methods (e.g., molecular clock, DNA barcode, racemization dating, and biomarkers) offer a unique source of information and provide robust clues into the co-evolution of life in modern and past environments. Two main limitations are noted and include an exceptional preservation of the organic material, which is not always the case, and the complexity and cost of the instruments involved in the analyses. These difficulties are limiting the factual applications in paleontological analysis. Although very little research has been carried out on the aforementioned methods, they however, provide improved answers to highly debated and unsolved biological and climatic issues and a window to better understanding the origin of life. Biomarker proxies will be further developed and refined to answer emerging questions in the Quaternary Period. [ABSTRACT FROM AUTHOR]

The southern Brazilian Pleistocene fauna exhibited a rich diversity of large mammalian herbivores, which are now extinct or locally extinct. In this study, we employed stable isotope analysis to investigate the past ecology of these animals. Specifically, we examined the carbonate fraction of bones and teeth and utilized compiled carbon and oxygen isotopic ratios from previous research publications. The δ13C values indicated that most specimens inhabited grassland environments, which aligns with environmental reconstructions based on pollen records of the "Campos" region. The dominant food resource for these herbivores consisted of C 3 photosynthesizers, mainly cool-season grasses. This preference can be attributed to the higher abundance and nutritional quality of cool-season grasses compared with warm-season grasses employing C 4 photosynthesis. The variability in δ18O values within and between taxa may suggest a seasonal climate. Based on these findings, we conclude that the environmental changes during the Pleistocene-Holocene transition were detrimental to the survival of these large herbivores. [ABSTRACT FROM AUTHOR]

The way we measure entities can have significant downstream effects on the transformations we can employ and the analytical methods we can use without breaking the link between the measurement and the aspect of reality they represent. Despite its obvious importance in any quantitative science, measurement theory is currently underused in biological research, including paleobiology. Proper statistical analysis is invaluable for extracting knowledge from data, but statistical models are blind to measurement theoretical issues because they can be applied to any dataset that fulfills their assumptions regarding the distributional properties of the data. Enhanced awareness of how distinct types of measurements possess different properties can improve the quality of scientific inquiry and lead to more meaningful inferences about the empirical world, including the fossil record. Measurement theory, a branch of applied mathematics, offers guiding principles for extracting meaning from empirical observations and is applicable to any science involving measurements. Measurement theory is highly relevant in paleobiology because statistical approaches assuming ratio-scaled variables are commonly used on data belonging to nominal and ordinal scale types. We provide an informal introduction to representational measurement theory and argue for its importance in robust scientific inquiry. Although measurement theory is widely applicable in paleobiology research, we use the study of disparity to illustrate measurement theoretical challenges in the quantitative study of the fossil record. Respecting the inherent properties of different measurements enables meaningful inferences about evolutionary and ecological processes from paleontological data. [ABSTRACT FROM AUTHOR]

The pollinating role of insects preceded the evolution of flowers. Insects pollinated gymnosperms before the appearance of angiosperms. The oldest record of pollinating insects is from the Upper Jurassic (~163 Ma), demonstrating the antiquity of animal pollination. We present a protocol for the definition and classification of pollinators and presumed pollinators in the fossil record of insects. Detailed study of bioinclusions in amber and fossil compressions can provide invaluable data for understanding insect-plants interactions in deep time. Inferring insect pollination from compression fossils and amber inclusions is difficult because of a lack of consensus on defining an insect pollinator and the challenge of recognizing this ecological relationship in deep time. We propose a conceptual definition for such insects and an operational classification into pollinator or presumed pollinator. Using this approach, we identified 15 insect families that include fossil pollinators and show that pollination relationships have existed since at least the Upper Jurassic (~163 Ma). Insects prior to this can only be classified as presumed pollinators. This gives a more nuanced insight into the origin and evolution of an ecological relationship that is vital to the establishment, composition and conservation of modern terrestrial ecosystems. [ABSTRACT FROM AUTHOR]

• Wide scapula movements could compensate for the reduced mobility of a short humerus. • Lowered head derived in freedom for forelimbs movement increasing the step length. • Limbs biomechanics increased the food encounter rate by improving acceleration. • Macrauchenia patachonica probably ran with the neck in a horizontal position. • The nasal retraction could be an adaptation for dust filtering. Macrauchenia patachonica Owen, 1838 was among the last and largest litopterns, an extinct order of South American native ungulates. Macrauchenia patachonica had anatomical peculiarities as extremely retracted nasals, enlarged cervical vertebrae, and limb bones proportions without good living analogs that lead to asking about its paleobiology. To quantitatively assess the strange combination of limb bone features in M. patachonica , we constructed an indicator of differences in anatomical adaptations for efficient running between forelimb and hind limb (IDFH). We also made a multivariate analysis using data on osteological ratios of living mammals and two other litopterns. We discuss several biomechanical and paleobiological implications of the striking differences between hind limb and forelimb design in M. patachonica. Our main suggestion is that M. patachonica , during fast locomotion, probably used a posture with the neck in a horizontal position. [ABSTRACT FROM AUTHOR]

The global brachiopod palaeobiogeography of the Mississippian is divided into three realms, six regions, and eight provinces, while that of the Pennsylvanian is divided into three realms, six regions, and nine provinces. On this basis, we examined coevolutionary relationships between brachiopod palaeobiogeography and tectonopalaeogeography using a comparative approach spanning the Carboniferous. The appearance of the Boreal Realm in the Mississippian was closely related to movements of the northern plates into middle–high latitudes. From the Mississippian to the Pennsylvanian, the palaeobiogeography of Australia transitioned from the Tethys Realm to the Gondwana Realm, which is related to the southward movement of eastern Gondwana from middle to high southern latitudes. The transition of the Yukon–Pechora area from the Tethys Realm to the Boreal Realm was associated with the northward movement of Laurussia, whose northern margin entered middle–high northern latitudes then. The formation of the six palaeobiogeographic regions of Mississippian and Pennsylvanian brachiopods was directly related to "continental barriers", which resulted in the geographical isolation of each region. The barriers resulted from the configurations of Siberia, Gondwana, and Laurussia, which supported the Boreal, Tethys, and Gondwana realms, respectively. During the late Late Devonian–Early Mississippian, the Rheic seaway closed and North America (from Laurussia) joined with South America and Africa (from Gondwana), such that the function of "continental barriers" was strengthened and the differentiation of eastern and western regions of the Tethys Realm became more distinct. In the Barents Ocean tectonic domain during the Pennsylvanian, the brachiopods on the northern margin of the Barents Ocean formed the Verkhoyansk–Taymyr Province, while those on the southern margin formed the Yukon–Pechora Province. The Mongolia–Okhotsk Province was formed by brachiopods of the Mongolia–Okhotsk Ocean tectonic domain. The Northern Margin of the Palaeo-Tethys Ocean Province and the Southern Margin of the Palaeo-Tethys Ocean Province were formed, respectively, by brachiopods on the northern and southern margins of the Palaeo-Tethys Ocean tectonic domain. South China and Southeast Asia were dissociated from the major continental blocks mentioned above, and formed the South China Province. [ABSTRACT FROM AUTHOR]

The combined use of the meiofauna (benthic foraminifers and ostracods) and geochemical data from three cores, recovered in distinct bathymetric sectors of the southern Adriatic shelf (Apulia, SE Italy), provides new insights on the relationships between shallow-marine environments, sediment fluxes and eutrophication trends over the last ∼7000 years. The stratigraphic distribution of meiofauna assemblages allows distinguishing a variety of facies associations, accumulated at proximal (Manfredonia Gulf), intermediate and distal shelf sectors. Spatial-temporal facies trajectories mainly reflect changes in fluxes of fine-grained, inorganic and organic particles at the seafloor. Major palaeoenvironmental shifts are paralleled by stratigraphic variations of Cr-Ni values, which represent effective provenance tracers for the Adriatic region. The correlation between the meiofauna content and trace-metal concentrations documents the link between the type of substrate (organic matter-OM and grain-size) and sediment provenance along the bathymetric profile and through time. After 6000 yr B.P., the gulf, partly sheltered by the Gargano Promontory, experienced the first increase in OM fluxes (transition from open-bay to prodelta). This turnaround occurred under the progressive change in sediment supply from southern Apennine source-rocks, poor in trace metals, to a mixed contribution including northern sources, enriched in chromium and nickel (mafic/ultramafic rocks of the Po River catchment) via the SSE-directed longshore drift. Alongside, prodelta clays in lateral transition to mud-belt deposits accumulated in the adjacent open shelf under the steady influence of the longshore drift. Finally, since ∼2000 yr B.P. a pervasive subaqueous delta system developed across the study area in response to increased sediment load by Po + Apennine rivers, likely induced by enhanced anthropic pressure during Roman times. This study highlights the key role played by the sediment routing system, coastal morphology and human land-use on shelf facies patterns and eutrophication trends, even in areas hundreds of km away from the main fluvial mouths. • Shallow-marine facies, meiofauna and sediment provenance are closely related. • Beyond water depth, meiofauna reflect organic content and grain-size sea bottom. • Longshore drift coupled with coastal morphology drives shelf facies patterns. • Human land-use can fuel environmental changes on shelves far from major deltas. [ABSTRACT FROM AUTHOR]

Recent renewed interest in using fossil data to understand how biotic interactions have shaped the evolution of life is challenging the widely held assumption that long-term climate changes are the primary drivers of biodiversity change. New approaches go beyond traditional richness and co-occurrence studies to explicitly model biotic interactions using data on fossil and modern biodiversity. Important developments in three primary areas of research include analysis of (i) macroevolutionary rates, (ii) the impacts of and recovery from extinction events, and (iii) how humans (Homo sapiens) affected interactions among non-human species. We present multiple lines of evidence for an important and measurable role of biotic interactions in shaping the evolution of communities and lineages on long timescales. Challenging the widespread perspective that long-term diversity patterns are shaped primarily by climate is not possible without using fossil record data to understand the role of biotic interactions. Important recent development and application of models that utilize data of both living and extinct species have enabled analyses to move beyond simply excluding potential abiotic drivers to explicitly modeling biotic drivers for the first time. Analyses of paleontological data show that biotic interactions shape the temporal diversity trajectories and rates of origination and extinction for numerous taxa. Extinction of keystone species has disproportionate impacts on biotic interactions among surviving species. Recovery from extinction events can be sped up or slowed down by biotic interactions among surviving species. Historically, humans (Homo sapiens) have acted as large, generalist predators, disrupting interaction networks among non-human species. [ABSTRACT FROM AUTHOR]

Lumentxa is a classic site in Basque Prehistory, excavated in three different phases during the 20th century, which has yielded evidence of both Pleistocene and Holocene occupations. In this article, we present a detailed study of the human remains from this site including paleobiological, taphonomic, biomechanical and chronological perspectives. The human assemblage comprises of a minimum number of seven individuals: three subadult and four adults, with both sexes represented, although part of the human collection is currently lost. We have obtained C14 dates from 4 of these 7 individuals indicating a prolonged funerary use of the cave from the Early Neolithic until the Bronze Age. We observed some biases in the skeletal representation which could be due to differences in the excavation methods between field seasons and/or the action of carnivores, the latter being evident in at least three of the individuals. The taphonomic modifications are typical off those found in the post-abandonment phases in cave funerary contexts. The relatively low number of individuals compared with other sites in the region and extended timespan over which the remains were deposited suggest that the cave was used only sporadically for funerary purposes. We report the first biomechanical data for a Neolithic individual from the Iberian Peninsula, which show greatest overall similarity to the Neolithic sample from France and Italy. Finally, the broad time period covered by the direct dates and the more complex taphonomic history than was previously assumed for such sites indicate that caution is warranted when assigning sepulchral caves to cultural periods in the Western Pyrenees when no direct radiocarbon dates have been obtained. [ABSTRACT FROM AUTHOR]

A systematic horizon scanning was undertaken to identify the up-to-date perspectives on paleontological research. A summarized evaluation (applicability and acceptability) was also provided to identify the challenges and opportunities of paleontological techniques. Present-day advances in molecular analyses and scanning techniques generate valuable new data to test old and recent systematic problems and provide a revolution in systematic paleontology. Integrating non-destructive high-resolution virtual solutions such as X-ray computed tomography and 3D-laser scanning with machine learning can be widely used for the analysis of internal features of fossils and more efficiently for automated taxonomy. The slow pace of the revolution in paleontological techniques can be attributed to the limited advanced statistical training and the cost of the instruments, software, and hardware needed for digitization and imaging. In addition, molecular techniques offer a unique source of information (e.g., biomarkers), however, costs and difficulties are limiting their applications. Sclerochronology using carbonate shells of well-preserved fossils (e.g., mollusks, corals, and fish) has the potential to reconstruct the paleoclimate at very high resolution (daily, seasonal, and annual). These approaches are revolutionary and will grow continuously to substitute traditional methods and will reduce time and human efforts. • Systematic horizon scanning was undertaken to identify the perspectives on paleontological research. • Physical and computational technologies have revolutionized the paleontological research. • Molecular analyses and scanning techniques provide a revolution in systematic paleontology. • Machine Learning in automated taxonomy is a very promising and exponentially growing. [ABSTRACT FROM AUTHOR]

In cave bear studies, stable isotope analysis of carbon and nitrogen is typically conducted on bone collagen. However, challenges arise due to biases in the classification of bones into age groups, which can be influenced by various factors that affect bone size. To overcome such issues, we present and evaluate a novel approach that involves sampling dental collagen from different ontogenetic stages of 45 fossil teeth, where only a portion of each tooth formed during the periods of interest was sampled. This approach enabled us to obtain a carbon and nitrogen fingerprint specific to a particular period in a cave bear's life without interference from earlier stages. Stable isotopic analysis revealed a rapid decrease in δ15N values from 3 to 15 months of age. After that, the δ15N values remain stable. Based on the nitrogen isotope composition (15N/14N), cubs aged 0–3 months exclusively consumed milk, while the gradual introduction of solid plant food occurs at 5–10 months, resulting in a shift in δ15N values. Based on similar δ 15N values in older age groups, it can be assumed that juveniles did not resume milk suckling after the first hibernation. The δ13C values increase until 15 months, followed by a gradual decrease until adulthood, potentially attributable to hibernation. The δ 13C values also seems to indicate isotopic differences between yearlings with low δ 13C values that successfully established hibernation and those with high δ 13C values that failed to hibernate and starved. This novel observation, i.e., decreasing δ 13C values from the second year of life onward, agrees with predicted isotopic skeletal collagen δ13C values calculated from modern brown bear blood plasma. In summary, the ontogenetic sampling strategy facilitated the acquisition of further paleobiological insights into the distinct life periods of cave bears. [Display omitted] • Ontogeny-based dental tissue sampling gives higher isotopic signal resolution. • Revealed new insight into the diet, physiology and behavior of cave bear. • The similarity of trends in δ 13C values with brown bears due to hibernation. • Detected differences in δ 13C values between hibernating and non-hibernating yearlings. • δ15N reveals a transition in diet and difference in wintering of yearlings. [ABSTRACT FROM AUTHOR]

Abstract Cretoxyrhina mantelli was a large pelagic lamniform shark geographically widespread during the Late Cretaceous, and well known because of several nearly complete skeletons from the Western Interior Seaway of North America. Here we report 15 partial skeletons belonging to lamniform sharks from the 'lastame' lithozone of the Upper Cretaceous Scaglia Rossa Formation of the Lessini Mountains (northeastern Italy). Seven partial but articulated skeletons include tooth sets that allow a confident attribution to Cretoxyrhina mantelli based on dental morphologies. We review the taxonomic history of C. mantelli , evidencing that the taxon was erected by Agassiz (1835) and tracing back four of the original syntypes. Based on calcareous plankton biostratigraphy, the rock in which the Italian skeletal remains are embedded is constrained to the middle-upper Turonian. Total length estimates of the specimens suggest that the sample includes the largest specimen of Cretoxyrhina mantelli (615–650 cm estimated total length) known to date. The placoid scale morphology indicates that C. mantelli most likely was a fast swimmer with a similar ecology as the extant white shark, Carcharodon carcharias. The associated skeletal elements of the specimens represent large chondrichthyan deadfalls and the cadavers decayed on the seafloor where they remained exposed for several months, as indicated by bioerosional traces, some of which are interpreted as a product of bone-eating worm activities and other bioerosional traces with Gastrochaenolites -like structure. The Cretoxyrhina mantelli remains described herein provide new information about the ʻlastameʼ vertebrate assemblage, which seemingly was strongly dominated by chondrichthyans, especially lamniform sharks. Highlights • Description of partial skeletal remains of the ʻginsuʼ shark Cretoxyrhina mantelli. • Nomenclatural Remarks about the species C. mantelli. • Emendation of the diagnosis of the species C. mantelli. • Paleobiological and taphonomic Remarks about the deadfalls of C. mantelli. • Micropaleontological analyses on the C. mantelli specimen matrix. [ABSTRACT FROM AUTHOR]

Highlights • Integrated Tonian & Cambrian stratigraphy in Huaibei region at the southeastern (SE) margin of the North China Craton (NCC). • The Great Unconformity is identified and positioned between the redefined Tonian Gouhou Formation and the Cambrian Houjiashan Formation at the SE margin of the NCC. • The Great Unconformity at the SE margin of the NCC represent a ca. 200–300 Myr gap. • New data provide insights into Tonian-Cambrian tectonic history in the NCC. Abstract The Great Unconformity between the Precambrian basement rock and Cambrian sedimentary cover has been extensively documented in Laurentia and may provide insights into the environmental context of the Cambrian explosion. A similar unconformity has been known in the North China Craton (NCC) and it offers an opportunity to constrain the geographic extent and geochronological magnitude of the Great Unconformity. However, the placement and magnitude of the Great Unconformity in the NCC, particularly at the southeastern margin of the NCC, is uncertain. For example, in the Huaibei region of the southeastern margin of the NCC, this unconformity has been variously placed beneath or above the Gouhou Formation, which preserves critical micro- and macrofossil assemblages with great paleobiological and biostratigraphic significance. This uncertainty significantly hampers our ability to fully appreciate the geological history of the NCC. To resolve this issue, we carried out an integrated biostratigraphic, sedimentary petrological and detrital zircon geochronological investigation on the Gouhou Formation and the overlying Houjiashan Formation in the Huaibei region. Our data suggest that the Great Unconformity lies within the Gouhou Formation and represents a ca. 200–300 Myr depositional gap: the Lower Member of the Gouhou Formation is of Tonian age whereas the Middle-Upper members of the Gouhou Formation are of early Cambrian. Therefore, we propose that the Gouhou Formation be redefined to contain only the Lower Member, and the Middle-Upper members be included in the Houjiashan Formation. Our analysis also confirms that the Great Unconformity can be widely recognized along the southeastern margin of the NCC. The recognition of the Great Unconformity in the Huaibei region helps to clarify the tectonic history, basin development, stratigraphic correlation, and paleogeographic reconstruction of the southeastern margin of the NCC during the Tonian–Cambrian periods. [ABSTRACT FROM AUTHOR]

Highlights • Strelley Pool Formation type locality has a maximum depositional age 3414 ± 34 Ma (2σ). • East Pilbara Terrane emergent by this time, with implications for development of life. • Detrital zircons >3.5 Ga hint at nature of cryptic early evolved crust. • Juvenile source to TTG until ca. 3.3 Ga then enhanced reworking of existing crust. • Relationship between early crust and 3.5–3.2 Ga TTG domes unknown. Abstract The detrital zircon record yields important information on crustal evolution that may be missing from extant magmatic rocks. The Palaeoarchaean to Neoarchaean East Pilbara Terrane (EPT), Western Australia, is the ancient core of the Pilbara Craton, and the archetypal granite-greenstone terrane. Magmatic zircon U–Pb crystallization ages from the EPT record crustal magmatism spanning 3.53–3.22 Ga. However, detrital zircons with ages as old as 3.65 Ga have been identified in EPT supracrustal sequences, which may provide key insights into the EPT's early Archaean history. The Strelley Pool Formation (SPF), one of the earliest EPT siliciclastic sedimentary successions, is a critical unit in the field of Precambrian palaeobiology, containing multiple lines of evidence for some of Earth's earliest life forms. The SPF was deposited on a continental shelf in a shallow water environment, upon perhaps the oldest preserved terrestrial erosion surface on Earth; it thus provides a record of a newly-emergent Palaeoarchaean continent. We report U–Pb, Lu–Hf and O isotope data from a suite of detrital zircon crystals sourced from the type locality of the SPF. Two hundred and five U–Pb detrital zircon analyses were undertaken via SIMS and LA–ICPMS. Four analyses define a young age peak of 3414 ± 34 Ma (2σ), which we interpret as a maximum depositional age. Zircon Hf isotope analyses yield εHf i of −3.5 to +5.2, clustering around chondritic values, with two-stage Hf crustal model ages of 3.9–3.5 Ga. Zircon O isotopes give a range in δ18O values from mantle-like (5.3‰) to more elevated (∼6.4‰). Taken together, the Hf and O isotope record, from new and published detrital and magmatic zircon crystals, implies a juvenile (mafic) source for evolved rocks of the EPT until ca. 3.3 Ga, after which time it experienced a period dominated by reworking of existing crust, possibly reflective of a change in geodynamics. The relationship between the cryptic core of the EPT, which is perhaps as old as 3.8–3.7 Ga, and the extant magmatic rocks that comprise the exposed Palaeoarchaean granite domes, remains uncertain. [ABSTRACT FROM AUTHOR]

Abstract A three-dimensionally preserved stellate fossil from the Middle-Upper Devonian of New York is described. Although it shares gross similarities with oral cones of anomalocaridids, we interpret it as the mold of the dorsal portion of the segmented alimentary canal of the rare, soft-bodied animal Paropsonema cryptophya. Together with two other dorsally preserved P. cryptophya specimens, such fossils strengthen the hypothesized link between two primitive deuterostome stem groups - the paropsonemids and the eldonids. Although the taxonomic affinities of these groups remain uncertain, it is important to illustrate fossils like these because they provide paleontologists with a 'search image' for more material that may elucidate patterns in early animal evolution or may help revise taxonomic interpretations. The new specimen of Paropsonema is also the youngest described occurrence of the paropsonemids and its sediment-filled gut is consistent with an epibenthic lifestyle for that group. Highlights • Discovery of the youngest known paropsonemid, an enigmatic soft-bodied group that is probably a stem-group deuterostome. • Three-dimensional preservation of the described fossils strengthens links between the eldonids and paropsonemids. • Please add a third highlight: The sediment-filled gut of Paropsonema supports a benthic mode of life for that group. [ABSTRACT FROM AUTHOR]

Abstract This special issue of Palaeogeography Palaeoclimatology Palaeoecology on "Cenozoic Climate Change in Eastern Asia" contains a series of multidisciplinary studies representing a wide range of research on paleovegetation, sedimentology, clay mineralogy, geochemistry, magnetostratigraphy, and climate modelling. The general significance of these studies is that analysis of terrestrial paleoclimate changes in eastern Asia may offer insights into the effects of Tibetan Plateau uplift, and ultimately the dynamic processes of global change that took hold throughout the Cenozoic. The present volume is Part II of this special issue. The first part of the special issue was dedicated to understanding eastern Asian paleoclimate variation during the Cenozoic by especially evaluating proxy data from geochemistry and climate modeling. Part II includes additional geochemical studies of terrestrial deposits from different regions of eastern Asia as well as climate modeling. Some of these papers focus on the impact or effect of these climatic changes on various floras and faunas in this region. In these studies, the period investigated ranges from the Eocene to the middle Holocene, thus encompassing most of the Cenozoic. Collectively, these studies provide significant new insights into the Cenozoic paleoclimate framework of eastern Asia. [ABSTRACT FROM AUTHOR]

Stegodon florensis florensis is an example of a diminutive insular stegodon from the early Middle Pleistocene bonebeds of Mata Menge, So'a Basin (Flores, Indonesia). We report the first insights into this Stegodon 's bone histology, which furthers our understanding of this species' palaeobiology, and evaluate the micro-anatomy and metabolic microstructural products retained in well-preserved rib bone tissue. A proximal rib fragment selected from a larger assemblage was sampled at three anatomical regions from which histological sections were produced. The sampling regions differed in cortical width size ranging from relatively thick to thin (17.94 mm to 6.31 mm). Bone tissue arrangement and histomorphometric variables measuring histological products of adult bone remodelling processes (secondary osteon population density and area, bone area, and Haversian canal percentage) were examined. The preservation of bone histology was very good, showing widespread Haversian bone with indication of several generations of remodelling processes, multiple resorption cavities, and the presence of 'super' (unusually large) osteons. Secondary osteon density and geometry varied with cortical width through the serial sections whereby the section with the narrowest cortex produced the highest secondary osteon density but also the largest osteon area. The effects of medullary cavity infilling on the endocortical region in the Stegodon rib may also relate to the adjacent periocortical region. The rib histology of this intermediate-sized dwarfed species shows, for the first time, a degree of secondary bone active remodelling in a Stegodon that indicates this was possibly a long-lived individual. Microscopic bone characteristics shared with other extinct and extant proboscideans may be useful in identifying Stegodon from fragmented mixed fossil assemblages. [ABSTRACT FROM AUTHOR]

Quantitative studies of fossil data have proven critical to a number of major macroevolutionary and macroecological discoveries, such as the 'Big 5' mass extinctions of the Phanerozoic. The development and easy accessibility of major meta-data sources such as the Paleobiology Database and Geobiodiversity Database have also spurred the widespread application of these data to testing ecological hypotheses at finer spatiotemporal and phylogenetic scales. However, preservational, sampling, and taxonomic issues, along with analytical decisions, can impact the degree of interpretative resolution and obscure biological 'signal' from error/bias-introduced 'noise'. The degree to which these factors can impact analytical interpretations is not well-documented in comparison to the scale of their application. Here, we review many forms of systematic bias that can creep into a paleoecological study, from the stage of data collection to the interpretation of analytical results. We provide two case studies where we artificially introduce such biases to previously-published datasets to illustrate their varying impacts on otherwise well-constrained data. The first case study focuses on the Cambrian Burgess Shale (konservat lagerstätte), and the second on bonebeds of the Cretaceous Belly River Group (konzentrat laggerstätte), with both representing highly-sampled, taphonomically-characterized, and spatiotemporally-constrained datasets developed through multiple years of sustained field collecting. In the former, we illustrate the impacts of collecting bias through quantitative comparisons of collected vs. discarded specimens over multiple field seasons and the impact of the loss of these data on ecological reconstructions and analysis. In the latter case study, we review the impact of preservational biases, differing approaches to their mitigation, and the impact of analytical decisions on ecological resolution. Lastly, we synthesize these case studies with our review of past approaches to propose a series of recommendations for future paleoecological and macroecological studies, emphasizing the continued importance of high-quality primary data and ongoing need for a first-principles approach to address existing issues of missing data. [ABSTRACT FROM AUTHOR]

In this paper, we report a new vertebrate ichnoassemblage from the mid- to late Permian red beds of the Ikakern Formation (Tourbihine Member, T2) from the Argana Basin of Morocco, to improve knowledge of paleobiology and palaeobiogeography. The ichnofossils comprise than 50 footprints organized as four trackways and assigned to the ichnogenus Hyloidichnus. The tetrapod tracks are preserved in convex hyporelief and concave epirelief on upper and lower mud-rich surfaces near the top of fine-grained sandstone units. The trackway pattern and the alternating arrangement of the pes-manus sets suggest a sprawling and symmetrical gait, with the movements of the front and hind limbs being of similar size, and it is likely that the animal moved at slow trot. We infer that the potential trackmaker was a captorhinomorph within the Moradisaurinae. This new fossil discovery helps reconstruct the palaeoenvironments and the palaeogeographic distribution of these Permian organisms, with Morocco acting as a faunal exchange gateway between western Gondwana and western Laurasia. Besides the tetrapod tracks, the red beds contain ubiquitous rain-drop marks, current ripples, plant fossil impressions, invertebrate burrows, tetrapod skin imprints, and a single insect wing that suggest that the strata were deposited in an episodically inundated alluvial plain. [Display omitted] • New ichnological evidence of captorhinids (Hyloidichnus) from Middle to Late Permian in North Africa. • Moradisaurines are suggested as the most potential trackmaker of small, large and broad Hyloidichnus. • Hyloidichnus trackways patterns suggest a gait of sprawling limbed tetrapods that would show a slow trot. • Morocco probably played a key-role as a gateway for faunal exchange of captorhinids. • These trackways are restricted to low-energy fluvial settingswith firm ground of sandy streambeds. [ABSTRACT FROM AUTHOR]

Highlights • Immunohistochemistry has been used to claim fossil protein preservation. • Reanalysis of a fossil feather reveals that it is inorganic, not proteinaceous. • The fossil feather was also covered in cyanoacrylate consolidant. • Antibody cross-reactivity might lead to false positive results in fossils. • Claims for ancient proteins require multiple lines of corroborating evidence. Abstract White fibers from a Late Cretaceous dinosaur Shuvuuia deserti stained positive for β-keratin antibodies in a 1999 paper, followed by many similar immunological claims for Mesozoic protein in bones and integument. Antibodies recognize protein epitopes derived from its tertiary and quaternary structure, so such results would suggest long polypeptide preservation allowing for sequencing with palaeobiological implications. However, proteins are relatively unstable biomacromolecules that readily hydrolyze and amino acids exhibit predictable instability under diagenetic heat and pressure. Furthermore, antibodies can yield false positives. We reanalyzed a Shuvuuia fiber using focused ion beam scanning electron microscopy, energy-dispersive X-ray spectroscopy, time-of-flight secondary ion mass spectrometry, and laser-stimulated fluorescence imaging, finding it to be inorganic and composed mainly of calcium phosphate. Our findings are inconsistent with any protein or other original organic substance preservation in the Shuvuuia fiber, suggesting that immunohistochemistry may be inappropriate for analyzing fossils due to issues with false positives and a lack of controls. [ABSTRACT FROM AUTHOR]

Devonian occurrences of Zoophycos are often observed in successions representing shelfal deposits and have been interpreted as the first expansion of this trace fossil during the Paleozoic. Dense Zoophycos occurrences in storm-generated Paleozoic beds have been interpreted as the result of ecological opportunist strategy when the tracemaker exploited quiet, nutrient garden substrates after storms. In the Devonian Ponta Grossa Formation (Pragian to Frasnian) of the Paraná Basin (Brazil), Zoophycos is both preserved in storm-generated strata indicating oxyc substrates, and in association with Chondrites and Phycosiphon suggesting dysoxic offshore deposition. This study focuses on the analysis of Zoophycos observed in the Devonian strata to understand the depositional context reflected by paleoecologic strategies and taphonomic signatures. We analyzed the ichnofabrics and sedimentary facies of Devonian sections from the Paraná Basin, focusing on the occurrences of Zoophycos . The tiering structure involving dense Zoophycos ichnofabrics demonstrated that shallower burrows (e.g., Asterosoma , Palaeophycus , Cylindrichnus , Schaubcylindrichnus , Skolithos ) reworked deep-tier burrows ( Chondrites , Phycosiphon , and Zoophycos ), indicating erosion of surficial levels. The dense Zoophycos ichnofabric representing the fair-weather suite obliterated primary sedimentary structures of storm deposits, which favored the visibility of deep-tier structures in a lam-scram pattern. In this sense, dense Zoophycos ichnofabric from Paraná Basin cannot be linked to an opportunistic behavior, but to an over-represented occurrence in space and time, being a taphonomic artifact related to low accommodation space in prograding context. The association with other trace fossils allowed the attribution of Zoophycos as a component of distal and archetypal expressions of Cruziana Ichnofacies rather than Zoophycos Ichnofacies. Concerning the vertical distribution of Zoophycos in the Paraná Basin, this trace appears in strata related to the first occurrence of land plants, being common in the Pragian–Eifelian interval, and declining in upper strata. This decline might be related to a potential structural change of the Paraná Basin during Middle Devonian. [ABSTRACT FROM AUTHOR]

Holocrinid crinoids ( Holocrinus ) are among the oldest, if not the oldest, post-Paleozoic crinoids, which are widely considered the stem-group isocrinids for the post-Paleozoic monophyletic subclass Articulata. Owing to their phylogenetic and stratigraphic position, the morphology and paleobiology of these crinoids have received considerable attention. Although the holocrinid stalk is similar to that of fossil and living isocrinids, it lacks flat and rigid synostosial articulations, which are sites specialized for autotomy. Holocrinids were thus long considered sessile, without the ability to re-attach. However, taphonomic data, such as specific pattern of preferred disarticulation at the distal facet of nodals, indicated that Holocrinus was likely capable of stalk autotomy and relocation. This trait, that is considered an anti-predatory adaptation against benthic predation, has recently served as example of fundamental change in benthic marine communities, such as the Mesozoic marine revolution (MMR). Here I describe stereom microstructure of the stalk of Early-Middle Triassic Holocrinus . The holocrinid stalk is mainly constructed of straight stereom passageways passing through the columnals, that are diagnostic of long through-going ligaments. At the distal symplexial nodal facet, however, fine and dense stereom, in which pores are irregular in outline and show no alignment, is observed. The latter stereom type strongly resembles synostosial stereom in living isocrinids, that is associated with short ligaments, specifically designed for autotomy. These findings thus strongly support stalk shedding abilities in holocrinids. These results emphasize that microstructural observations, coupled with taphonomic data, may provide more insights into functional inferences than macromorphological data alone. [ABSTRACT FROM AUTHOR]

The continental colonization process by plants is an underexplored theme in Brazil, especially concerning taphonomic studies of plants that existed during this age. This study aims to interpret the taphonomic and paleoenvironmental settings that best represent the fossil plant assemblages preserved in the upper strata of the Furnas Formation (Lower Devonian of Paraná Basin), at Jackson de Figueiredo county, municipality of Jaguariaíva (Paraná), clarifying the potential of these fossil plant assemblages for paleogeographic reconstructions. Taphonomic and sedimentological signatures were analyzed and submitted to multivariate statistical analyses (cluster and correspondence analyses). Two taphonomic groups were identified (Taphofacies A and B). The interpretation of the two groups allowed the visualization of: Taphofacies A, which consists of samples with a dispersed degree of packing, fragmented plant fossils, 40% mica with sizes between 0.5 and 1 mm and no trace fossils, is representative of relatively high-energy conditions; and Taphofacies B, which consists of densely packed plants with partial degree of fragmentation, 10% mica with sizes under 0.5 mm and both horizontal and vertical trace fossils, is representative of relatively low-energy conditions. Our taphonomic data are consistent with previous facies interpretations of a lagoon/interdistributary bay environment. In this context, taphofacies A represents episodic sedimentation events influenced by fluvial dynamics, yielding assemblages that are not suitable for paleogeographic interpretations, while Taphofacies B represents fossil assemblages originated in a low-energy sedimentary regime, with utility for paleogeographic reconstructions. [ABSTRACT FROM AUTHOR]

A comprehensive set of organic and inorganic geochemical proxies, clay mineralogy, and molecular fossils are presented from two biostratigraphically well-dated oil shale horizons of Egypt, within the Upper Cretaceous Duwi and Dakhla formations. The studied oil shales were deposited within intracratonic sedimentary basins in a broad northern African epeiric sea. Calcareous nannofossil biostratigraphy indicates that the oil shales range from early to late Maastrichtian in age, covering nannofossil zones UC18, UC19, and UC20. The oil shales contain smectite and kaolinite as the main clay minerals that formed by weathering of precursor basement rocks. The relative abundances of clay minerals and several geochemical proxies (e.g. C-value, CIA, Ga/Rb, Rb/Sr and Sr/Cu), along with the occurrence of warm-water nannofossil taxa, demonstrate that the Maastrichtian oil shales accumulated under a warm, arid to humid greenhouse climate during a general Maastrichtian cooling trend. This episode of oil shale deposition in Egypt coincided with the first potential imprint of the global warming, that has been recorded during early-to-late Maastrichtian times (~70.6–67.7 Ma). Elevated eolian terrigenous input was recorded within the Duwi Formation oil shales, shown by high Ti/Al, Si/Al, Zr/Al and low La/Lu ratios. The Duwi Formation environment was characterized by enhanced salinity and a stratified water column, compared to that of the Dakhla Formation, shown by elevated values of the gammacerane index, tetracyclic terpane, β‑carotene and Sr/Ba ratio. The CaCO 3 content and carbonate/siliciclastic ratio indicate that the Dakhla Formation oil shales were deposited during a relative sea-level rise in a deeper marine setting than the Duwi Formation oil shales. The data further imply a wind-driven upwelling scenario of nutrient input s that simulated primary production and increased organic matter fluxes. Thus, paleoclimate and paleoceanography had a considerable impact on organic matter enrichment. [ABSTRACT FROM AUTHOR]

The evolution of the San Marino carbonate succession, developed on a wedge-top basin of the northern Apennines during the Middle Miocene (Torriana outcrop, Marecchia Valley), was studied through a high-resolution stable isotope analysis on different carbonate components. A marked positive carbon isotopic excursion is identified at ca. 16 Ma. The excellent correlation of the San Marino δ 13 C carbonates with the global δ 13 C reference curve from Zachos et al. (2008) allows to link the marked positive δ 13 C present in the San Marino section with the global carbon isotope maximum of the Monterey event. Subordinate long-eccentricity-driven δ 13 C cycles (~405 kyr) as recorded by Holbourn et al. (2007) were also identified. The correlation with carbon signatures of coeval successions of the Mediterranean region shows that this main carbon isotopic excursion at the Burdigalian–Langhian boundary is widely recorded and predates the crisis of these heterozoan shelves. The demise of the San Marino shelf resulted from a combination of global and regional factors that controlled the nutrient budget, the detrital input and the subsidence of the basin. The high-resolution chemostratigraphy of San Marino succession shows that even though the shelf evolved in the complex setting of a wedge-top basin, which should be largely influenced by local factors (i.e. tectonic subsidence and detrital input), it records the Monterey event and its eccentricity paced rhythms with high precision. This highlights the strong connection of the Monterey event with the development and subsequent demise of shallow water carbonate depositional systems in the Mediterranean, irrespective of variable and changing local conditions. [ABSTRACT FROM AUTHOR]

We report the occurrence of sponge borings in composite molds of heteropectinid shells from Early Permian marine siliciclastic deposits of the Paraná Basin of southern Brazil. Sponge borings are preserved mainly as chambers ( Entobia ) and channels ( Entobia and Clionolithes ). Three preservational variations of Entobia are present, morphologically equivalent to the alpha, beta, and gamma ontogenetic stages of clionid sponges. This equivalence suggests that the ontogenetic behavior in clionid sponges remains the same since Early Permian times and points to a conservative evolutionary trend for this group. The pattern of bioerosion and other taphonomic signatures indicate rapid shell burial due to frequent and energetic storm events that might have limited the time available for bioerosion activity. The new findings improve the Paleozoic record of Entobia and Clionolithes and indicate that sponge borings have potential to be preserved in ancient siliciclastic rocks. [ABSTRACT FROM AUTHOR]

A new carbon isotope excursion was recovered from the Capitanian marine carbonates at the Rencunping (RCP) section of South China. Significantly, a pronounced excursion with elevated δ 13 C carb values over +5‰ was coeval with the conodont Jinogondolella prexuanhanensis Zone and resembles the Kamura event recorded in Tethys. The excursions in δ 13 C carb , constrained by conodont biostratigraphy, however, present inconsistent carbon cycle behaviors, especially between the separated basins in South China, and evidently reflect regional litho-facies controls. In addition, a transitional environment in association with a fall in sea level, was recovered from deposits of anoxic cherty carbonates subsequent to shallow-water carbonates around the positive excursion in δ 13 C carb . Accordingly, instead of this being a signal of global-scale climatic cooling, we suggest that the positive excursion in δ 13 C carb can be attributed to eutrophication effects regionally along a continental shelf. In this scenario, the increasing dissolved O 2 level in the mixing zone that induced by the initial sea-level fall will efficiently impede denitrification and increase the bio-available N in N:P ratio to satisfy the demands of primary producers in surface waters. Subsequently, deposits of shallow-water carbonates comprising calcareous algae and massively-bedded lime muds accumulated widely around South China. These deposits appear to represent an unusual environment and ecosystem fertilized, perhaps, by the weathering products from the earliest stages of volcanism prior to the main Emeishan flood basalt eruptions at the Guadalupian-Lopingian boundary (GLB). [ABSTRACT FROM AUTHOR]

Diacodexeidae are the first representatives of Artiodactyla in the fossil record. Their first occurrence is at the very base of the Ypresian (earliest Eocene, 56.0 Ma) with Diacodexis , a genus well diversified during the early Eocene in Europe, especially during the MP7–MP8 + 9 interval. However, most of European species are documented by scarce material, retrieved from single localities. In this work, we describe new Diacodexis material from ∼MP7 and ∼MP8 + 9 localities of Southern Europe, including material of D. antunesi from Silveirinha, considered as the most primitive European Diacodexis species, and material from three localities from Southern France (Fordones, Palette, and La Borie). The new material documents Diacodexis premolar morphology and deciduous dentition which bear potentially important phylogenetic information, as well as astragali, including a specimen from Silveirinha that constitutes the earliest occurrence of an astragalus of the genus Diacodexis in the European fossil record. Investigation of the enamel microstructure reveals that early European species had a simple enamel pattern with one-layered Schmelzmuster composed of ‘basic’ radial enamel only, instead of the two-layered Schmelzmuster (thin radial enamel + thick layer of Hunter-Schreger bands) observed on North American species and so far considered to represent the primitive condition within Artiodactyla. In accordance with previous studies, our observations highlight that Diacodexis gigasei from Belgium is morphologically closer to the North American species D. ilicis than to D. antunesi from Portugal. The latter species, together with D . aff. antunesi from Fordones, appears to be morphologically closer to the Asiatic taxa D. indicus and D. pakistanensis . Finally, we found numerous similarities between D. cf. gigasei from Palette and D. gigasei , a result that challenges the intra-European provincialism that characterizes the earliest Ypresian. Diacodexis gigasei could be one of the rare species shared by the northwestern and southwestern European bioprovinces. [ABSTRACT FROM AUTHOR]

Twenty species belonging to fifteen genera of cyclostome and cheilostome bryozoans encrusting belemnite rostra are described from the late Campanian to Maastrichtian of the Aktolagay Plateau, in western Kazakhstan. Due to the moderate to poor preservation of the material, only four cheilostome species are identified down to the species level: Wilbertopora ? besoktiensis (Voigt, 1967), ‘ Aechmellina ’ stenostoma Voigt, 1930, and two new species, ‘ Aechmellina ’ viskovae and Cheethamia aktolagayensis . All remaining species are left in open nomenclature. Type material of Wilbertopora ? besoktiensis from the early Maastrichtian of the Mangyshlak Peninsula in Kazakhstan, has been re-examined. Palaeobiogeographical and implications are discussed. Cheilostomes slightly dominated over cyclostomes in the Aktolagay Plateau fauna encrusting on belemnites in terms of diversity. The dominant colony forms observed were spots and sheets. [ABSTRACT FROM AUTHOR]

Planktic foraminiferal analyses of the Campanian-Maastrichtian sediments from four sections a long a Tethyan transect in north Sinai, enabled to recognize twelve planktic foraminiferal zones and subzones ranges from CF11 to CF1, in addition to Globotruncanita elevata Zone. The planktic morphotypes were basically subdivided into three groups, Deep taxa (DT), Surface taxa (ST) and subsurface e Taxa (SsT) to provide insights into paleotemperature changes. Q-mode cluster analysis as well as the relative dominance of planktic groups revealed the recognition of long term warming in the Campanian with warmest interval in Globotruncana ventricosa . Whereas minor cold events intervened at 80, 78.4, 75.4, 73.6 and particularly at 72 Ma indicates the Campanian/Maastrichtian boundary. The Maastrichtian (CF7-CF1) were characterized by successive warm-cool intervals superimposed on long term cooling, the late Maastrichtian (CF3-CF1) in particular, is characterized by alternate warm cold interval, where the last event was cooling, prior to K/T boundary. The Campanian- Maastrichtian paleodepth in North Sinai indicate that the cooling event much consistent with regression phases and equivalent to global eustasy whereas, the warm interval is consistent with the transgression phases. It is concluded that the late Maastrichtian was much controlled with local tectonics since CF3 and prior the K/T boundary. [ABSTRACT FROM AUTHOR]

This study presents a high-resolution, chronologically well-constrained pollen record from Lake Kushu (45°25′58″N, 141°02′05″E) and a record of archaeobotanical remains from the nearby Hamanaka 2 archaeological site. The pollen record suggests continuous long-term cooling, which parallels the decline in Northern Hemisphere summer insolation. This cooling trend is overlaid by several rather quick transitions towards cooler conditions (ca. 5540/5350, 1550, and 390 cal BP) and one distinct decadal-scale cold event around 4130 cal BP. These shifts, on one hand, correspond with major hemispherical or global-scale climate transitions/events, including the ‘Holocene Climate Transition’, the onset of the ‘Dark Ages Cold Period’ main phase, the ‘Little Ice Age’, and the ‘4.2 kiloyear event’, respectively. On the other hand, the shifts partly coincide with transformations in the Hokkaido prehistoric cultural sequence including the onset of the Middle Jomon (ca. 5000 cal BP), the Middle/Late Jomon transition (ca. 4000 cal BP), the immigration of Okhotsk culture groups (from ca. 1500 cal BP), and the establishment of the Classic Ainu culture (ca. 350 cal BP). AMS radiocarbon dating of charred macrobotanical remains from Hamanaka 2 suggests three discontinuous occupational periods ca. 390–50 BCE, 420–970 CE, and from 1640 CE, which correspond to the northern Hokkaido Epi Jomon (ca. 300–100 BCE), Okhotsk (ca. 500–1000 CE), and Classic Ainu (ca. 1600–1868 CE) cultural phases, respectively. While impact on the island's natural environments (forest clearance) was marginal during the Epi Jomon phase, it became significant during the Okhotsk and the Classic Ainu culture phases. [ABSTRACT FROM AUTHOR]

Different taphonomic processes throughout the history of a fossil assemblage may preserve, modify or destroy, particular palaeobiological traits, but these processes always increase taphonomic information of the past. Similarly, fossils are affected during later stages of taphonomic history, i.e. excavation, preparation, study and storage of fossils, known as sullegic and trephic phases. Tools used during excavation and preparation of fossils can damage them and produce marks on their surface. Some of these recent marks highly mimic taphonomic marks produced before excavation. Both modern and fossil marks lead to misinterpretations and erroneous conclusions when similarities are not clearly detected. In order to distinguish recent from ancient marks, several diagnostic criteria resulting from experimental work are described in this paper. [ABSTRACT FROM AUTHOR]

Once perceived as a continent-wide extinction event, doubts have been raised as to the severity and extent of the Vallesian Crisis. In this paper, we use the high-resolution late Aragonian to middle Turolian micromammal record from both the coastal Vallès-Penedès Basin and inland Calatayud-Teruel Complex to determine geographic extent of this late Miocene turnover event and its effects within the reaches of the Iberian Peninsula. Differences in faunal composition between the two regions confirm that the event was much less severe than previously thought. Surprisingly, the diversity peaks in the two regions do not coincide. Whereas at the coast highest diversity is found in the early Vallesian (just before the turnover), in the inland it peaks in the late Vallesian. Several taxa never made it inland as reflected by the low similarity between both regions during the early Vallesian, suggesting that the Vallès-Penedès was indeed unique and consistently showed higher affinities with northern regions. The large differences even at relatively short distances support the idea that the ‘Vallesian Crisis’ was a local event. [ABSTRACT FROM AUTHOR]

The Middle Pleistocene site of Fontana Ranuccio (Anagni Basin, Central Italy) has yielded nearly 25,000 remains belonging to large and small vertebrates, including four isolated teeth of Homo sp., and a rich lithic assemblage containing bone tools. Here we provide new dental wear analyses of the ungulate community to improve the palaeoenvironmental reconstruction for the site. Analyses indicate a mostly browsing diet for the cervids and a grazing diet for the perissodactyls Stephanorhinus sp. and Equus cf. E. mosbachensis , suggesting a range of habitats that spanned from forests to open grasslands. A discrepancy between mesowear and microwear results is observed in the case of the bovid, Bos primigenius ; this can be tentatively explained as resulting from a temporal switch towards a sub-optimal diet, possibly reflecting the effects of marked seasonality. Findings shed new light on the structure of the 400 kyr ecosystems that existed during the early occupation of Homo in Europe. [ABSTRACT FROM AUTHOR]

Here we present a revision of dipnoans from the Middle-Upper Buntsandstein and the Lower Muschelkalk (Lower-Middle Triassic) of the Holy Cross Mountains (southeastern Poland) and from the Middle Buntsandstein of northeastern Poland. Two genera are identified: Arganodus and Ptychoceratodus . Specimens resemble synchronous species from the European part of Russia. It is the first Middle Triassic finding of Arganodus worldwide. Ptychoceratodus is reported for the first time from the Lower Triassic of Poland. It is its oldest known occurrence in Europe. The Holy Cross Mountains stands between the area of European Russia and the Central European Basin which were both inhabited by Arganodus and Ptychoceratodus in the Early-Middle Triassic. Resulting from a summary of palaeobiogeographic data of these two genera their distributional patterns are hypothesized herein. In the Early Triassic both genera often co-occurred in many regions. Starting from the Middle Triassic their ranges split into two almost separate ones. They reflect the palaeolatitudinal belts in the Late Triassic with Arganodus in the northern tropic belt and Ptychoceratodus along the palaeolatitudes 30°. [ABSTRACT FROM AUTHOR]

The Upper Cretaceous sediments in the Moghan area, NW Iran, contain diverse planktonic and benthic foraminifera, with a total of 33 genera and 53 species (17 genera and 38 species of planktonic foraminifera and 16 genera and 15 species from benthic foraminifera), which led to the identification of six biozones spanning the middle Campanian to late Maastrichtian. A detailed paleontological study and biostratigraphic zonation of these sequences has been carried out in four surface sections. This study shows that there are two different facies in the Moghan area, based on the faunal content. A deep open marine condition exists in the Molok, Selenchai and Nasirkandi sections. In these sections, Upper Cretaceous sequences have diverse planktonic foraminiferal species including the Globotruncana ventricosa (middle to late Campanian), Globotruncanella havanensis (late Campanian), Globotruncana aegyptiaca (latest Campanian), Gansserina gansseri (latest Campanian to early Maastrichtian), Contusotruncana contusa- Racemiguembelina fructicosa (early to late Maastrichtian) and Abathomphalus mayaroensis (late Maastrichtian) zones. This deep open marine setting grades laterally into shallower marine condition dominated by large benthic foraminifera such as Orbitoides media , Orbitoides gruenbachensis , Orbitoides cf. apiculata , Lepidorbitoides minor , Pseudosiderolites sp., Siderolites praecalcitrapoides , Siderolites aff. calcitrapoides and Siderolites calcitrapoides . This facies is mainly recorded in the Hovay section. A detailed biostratigraphic zonation scheme is presented for the studied sections and correlated with the results of other studies in the Tethyan realm. This is the first biozonation scheme for Upper Cretaceous sequences of the Moghan area that can be used as a basis for ongoing studies in this area and other parts of Tethys basin. [ABSTRACT FROM AUTHOR]

The main Karoo Basin (MKB), internationally renowned for its wealth of fossil tetrapods, has been lithostratigraphically subdivided into three discrete regions: two (east and west) proximal facies adjacent to the Cape Fold Belt, and a distal facies, away from the Cape Fold Belt. Because of lithological differences between formations of the proximal and distal sectors of the MKB, it has been difficult to correlate time-equivalent lithostratigraphic units in the different sectors. Palynology provides a tool for refining stratigraphic correlations within the MKB, but only species with restricted ranges are biostratigraphically significant. Restricted-range palynomorph taxa from the Ecca and Beaufort groups indicate the following relationships: the lowermost Vryheid Formation palynoflora can be strongly correlated with that of the Prince Albert Formation, whereas the Whitehill–Collingham formations and No. 2 seam (Vryheid Formation), and the Ripon Formation and No. 4 seam (Vryheid Formation) can be tentatively linked using palynology. The lower–middle Normandien Formation in the north is chronologically equivalent to the Ripplemead member of the Balfour Formation in the south. Although the Ecca–Beaufort Group boundary is known to be diachronous, restricted-range palynomorphs cannot yet confirm that the uppermost Ecca Group in the northern part of the basin was deposited at the same time as the lower Beaufort Group in the south. This study demonstrates that despite diachronous ranges of some taxa, palynology is useful in correlating age-equivalent lithostratigraphic units in the proximal and distal sectors of the basin. A new First Appearance Datum (FAD) palynozonation for the Karoo is presented that is calibrated by the most recent radiometric dates for South Africa, Australia, and South America. The new zones are also correlated with Permian successions in Antarctica, Zambia, Botswana, and India. Future palynostratigraphic work in South Africa must take into account the ranges and FADs of these palynomorph taxa in order to make meaningful biostratigraphic correlations in the Karoo Basin and across Gondwana. [ABSTRACT FROM AUTHOR]

A detailed understanding of silica postdepositional transformation mechanisms is fundamental for its use as a palaeobiologic and palaeoenvironmental archive. Amorphous silica (opal-A) is an important biomineral, an alteration product of silicate rocks on the surface of Earth and Mars, and a precursor material for stable silica phases. During diagenesis, amorphous silica gradually and gradationally transforms to opal-CT, opal-C, and eventually quartz. Here we demonstrate the early-stage maturation of several million year old opal-A from deeply weathered Early Cretaceous and Ordovician sedimentary rocks of the Great Artesian Basin (central Australia). X-ray diffraction, scanning electron microscopy, and electron probe microanalyses show that the mineralogical maturation of the nanosphere material is decoupled from its chemical properties and begins significantly earlier than micromorphology suggests. Non-destructive and locally highly resolved X-ray microdiffraction (μ-XRD 2 ) reveals an almost linear positive correlation between the main peak position (3.97 to 4.06 Å) and a new asymmetry parameter, AP. Heating experiments and calculated diffractograms indicate that nucleation and growth of tridymite-rich nanodomains induce systematic peak shifts and symmetry variations in diffraction patterns of morphologically juvenile opal-A. Our results show that the asymmetry parameter traces the early-stage maturation of amorphous silica, and that the mineralogical opal-A/CT stage extends to smaller d-spacings and larger FWHM values than previously suggested. [ABSTRACT FROM AUTHOR]

The Brazilian Paleozoic ichthyofauna from the Parnaíba and Amazonas basins regard a sparsely known diversity, including chondrichthyans and acanthodians, besides some osteichthyan remains. This work proposes a revision of the fossil material from these two sedimentary basins and synthesizes the morphological aspect of such material trying to understand the influences of those fossils to the paleontology of the region, comparing the Brazilian fossils with other gondwanan faunas. The Brazilian Paleozoic fish fauna shows great resemblance to those of Bolivia, especially during the Devonian. Many of the Acanthodian spines from the Manacapuru Formation (Amazonas Basin), and the Pimenteira Formation (Parnaíba Basin), are comparable to the taxa found in Bolivia. The lack of more Placoderm remains in the Brazilian outcrops is similar to the low diversity of this group in Bolivia, when compared to other South American and Euramerican localities. The most diverse Brazilian ichthyofauna is encountered in the Permian Pedra de Fogo Formation where numerous chondrichthyans and ‘paleopterygians’ remains are found, together with dipnoans and actinistians. Despite the apparent lack of more representative Paleozoic ichthyofaunas in Brazil, the available material that ranges from Lower Devonian to early Permian from Brazil bears important taxa that could address valuable taxonomic and biogeographic informations. [ABSTRACT FROM AUTHOR]

With high organic content and abundant microbiota, feces are typically only preserved for a few days, weeks or months after deposition and mostly never enter the fossil record. The range of depositional conditions favorable for the preservation of feces is narrow, but depends on a large number of biotic and abiotic factors. Moreover, because the chemistry and microbiology of feces often promotes mineralization, discriminating between coprolites and some inorganic sedimentary structures is often difficult. We propose a protocol to identify coprolites in the fossil record that encompasses all the criteria previously defined. We then apply this protocol to identify putative coprolites from the lower Carnian (Upper Triassic) Chañares Formation of northwestern Argentina. Using a variety of analytical methods and several different criteria, we were able to identify them as carnivore coprolites. Based on extant analogs, the most probable producer would be a small carnivorous cynodont or archosauriforms, and the prey is likely a tiny therapsid or archosauriform. This is the first detailed report of carnivore coprolites from this unit, and provides direct evidence of trophic links in the Chañares ecosystem. [ABSTRACT FROM AUTHOR]

Fossilized feces (coprolites) are remarkable tools for paleobiology and paleoecology assessment. Here they are used to reconstruct the Permian interactions between organisms that once composed a large interior sea at Western Gondwana. Coprolites from the Corumbataí Formation were retrieved from a distal tempestite layer and investigated about their morphology, texture, and food inclusions, applying hand sample description, petrographic analysis, EDS/SEM, and confocal microscopy. Seven morphotypes were recognized, which were probably derived from fishes, like xenacanthid sharks, basal Actinopterygii (Palaeonisciformes), petalodontids/dipnoan, and possible tetrapods, such as temnospondyls and diapsids. Four coprofabrics were also recognized and allowed the establishment of four different feeding/digestive strategies and, consequently, the definition of carnivorous-piscivorous predators as top predators, but also as occupants of intermediate trophic niches. Durophagic/deposit feeders were occupants of inferior trophic niches. This food web developed under stressful conditions, during a moment of aridization of the Paraná Basin, in association with ostracods and sponges' proliferation, and during this moment palaeoniscoid fishes seem to have been the main exploited resource in the environment. [Display omitted] • A four-trophic niche structure for Permian Gondwanan aquatic food web is revealed. • Producers were mostly fishes but there is evidence of cryptic tetrapod producers. • Sediment-rich coprolites are indicative of possible detritivorous bottom feeders. [ABSTRACT FROM AUTHOR]

The Early Toarcian (Early Jurassic) global marine mass extinction is associated with one of the most important environmental perturbations of the Mesozoic, the Toarcian Oceanic Anoxic Event (T-OAE), usually interpreted as a global oceanic anoxic event. In the Lusitanian Basin (LB) — one of the reference areas for the study of the T-OAE — despite an elevated extinction rate among marine invertebrates, the anoxia hypothesis has been discarded based on geochemical and isotopic data. In the Fonte Coberta section the T-OAE is characterised by the extinction of the previously well-represented brachiopod taxa, a decreased abundance of ammonoids, and the establishment of a well-developed endobenthic community mainly composed by Thalassinoides tracemaker, which indicates favourable environmental parameters at least for this community. Thus, the palaeoenvironmental changes associated with the T-OAE event bear a minor incidence on the macrobenthic tracemaker community at the level of extinctions and changes in diversity or abundance; yet they exert a major effect on the behaviour and palaeobiology of tracemakers. The Thalassinoides specimens show an exclusively horizontal development and unusual architectural features during the extinction interval, tied to behavioural adaptations to nutrient availability and/or substrate firmness. Smaller burrow diameters are registered at the base of the T-OAE, and then an increase is observed during the T-OAE. This could be associated with a palaeobiological response (Lilliput effect) to palaeoecological changes at the beginning of the T-OAE, followed by a progressive change to pre-event environmental parameters. This study therefore sheds light on how environmental alterations can determine specific behavioural and palaeobiology changes of the producer, as reflected by variations in significant features of Thalassinoides architecture. [ABSTRACT FROM AUTHOR]

Bones in the fossil record sometimes exhibit unusual structures that can be attributed to pathologies, taphonomic alterations, or morphological variation. The goal of this work is to describe three bone abnormalities present in the type specimen of Bonitasaura salgadoi from the Cretaceous of north Patagonia, Argentina. The studied material corresponds to a left femur, a left metatarsal III, and a right prezygapophysis of a mid-caudal vertebra. Macroscopic and/or histological examinations were conducted, and a discussion concerning the origin of each abnormality is provided. The results of this study suggest that the anomalous structures are pathologies. In the femur, an osteoblastic tumor was identified by the presence of a large outgrowth of ovoid appearance with a spiculated microstructural pattern. The metatarsal III shows an enthesophyte (or bone spur) based on its location, shape and growth in parallel to the long axis of the bone element. Finally, the abnormal tissue observed in the prezygapophysis of the caudal vertebra was determined to be an infection by the presence of reactive new bone associated with a local widening of the subperiosteal margin and a sinus of drainage. This is the first report of multiple pathologies in a single specimen of a titanosaur, and it provides new insights about paleopathologies in sauropod dinosaurs. [ABSTRACT FROM AUTHOR]

Studies of the palaeobiology of titanosaur eggs are significantly more common than studies of titanosaur-egg-bearing strata. Nevertheless, the latter provide significant insight into palaeoenvironmental conditions associated with the egg-laying behaviour. This study examines titanosaur-egg-bearing strata of the Upper Cretaceous Los Llanos Formation (La Rioja, Argentina) and relates them to the laying and preservation of titanosaur egg clutches. Los Llanos Formation is a predominantly sandstone succession throughout represented by palaeosol profiles. Five titanosaur egg clutches were recovered from the Bw horizon of an Inceptisol profile. This palaeosol type, named Tama pedotype, constitutes 69% of the entire succession, by thickness. Rare planar, and undulating lamination and cross stratification, quartz-grain surface microtextures and ventifacts are indicative of the interaction of fluvial-aeolian processes of sedimentation during accumulation of the parent material on the distal part of a coalescent alluvial fan system ( bajada ). Highly abundant root traces, reddish colour, clay coatings and calcium carbonate nodules testify that the Tama pedotype had abundant vegetation cover, and was developed in well-drained conditions under the influence of a semiarid climate regime. Palaeosol horizons with exaggerated thickness and diffuse boundaries indicate a cumulative pedotype, whereby the soil developed in response to continuous accretion via on-going sedimentary processes. Morphological features of eggshells suggest that titanosaurs dug holes in the topographic surface to lay eggs. Thus, palaeosols seem to have been putative areas for the laying of titanosaur eggs. Actually, it is uncommon for palaeosols to constitute sites for the preservation of eggs, since soils typically develop in response to long episodes of weathering. However, cumulative palaeosols can provide ideal conditions for egg burial and preservation. In cumulative soils, the residence time of an object within the weatherable thickness of a soil is reduced to < 10 3 years, thereby significantly increasing the long-term preservation potential of eggs. [ABSTRACT FROM AUTHOR]

Over the past five decades, fossil deposits within the Upper Burgi, KBS and Okote members at East Turkana in northern Kenya have provided many important insights into hominin behavior and ecology during a critical period in hominin evolution between 2.0 and 1.4 Ma. In this study, we use a large compilation of faunal abundance data from paleontological and archaeological collections at East Turkana dating to this time interval to investigate temporal patterns in large mammal taxa, ecosystem evolution and hominin ecology. Our analyses indicate that although portions of the ecosystem were dominated by mesic grasslands, the relative proportion of mesic and arid grassland environments varied though time. We document a major transition in the family Suidae with an increase in the abundance of fossils attributed to the Metridiochoerus lineage coeval with the local extinction of the Notochoerus lineage and decline in abundance of the Kolpochoerus lineage. Finally, by comparing the proportional representation of mammalian taxa found in paleontological collections versus those found in archaeological collections, our data suggest that archaeological sites at East Turkana, particularly those c. 1.5 Ma, contain disproportionately large numbers of alcelaphin bovid remains. This could reflect 1) hominin prey choice, 2) hominin hunting/scavenging habitat choice, or 3) a combination the two. [ABSTRACT FROM AUTHOR]

The Intra-Sudetic Basin is essentially a post-orogenic (Variscan) continental basin with a depositional history that ranges from the late Viséan to the Triassic. The fossil record in the Czech part of the basin, although discontinuous, spans the interval from the late Viséan to the Asselian. Middle Baskhirian (late Namurian) to Asselian adpression floras collected from boreholes, coal mines and outcrops permit reconstruction of the stratigraphic ranges of individual species in considerable detail, and reveal changes in plant diversity and vegetation patterns throughout this ~ 25 Myr interval at high resolution, even to the scale of individual coal-bearing cycles. Species diversity recorded in the rock record throughout the studied interval mainly was controlled by climatically-driven potential for preservation of plant material, which was highest in poorly drained/waterlogged habitats (wetlands, lakes) concentrated in basinal lowlands and representing major windows of preservation. Low fossilization potential is typical for well-drained fluvial habitats, now represented by red beds deposited under drier (seasonal) climate. Diversity in major windows of preservation was highest during the late Langsettian and Duckmantian (> 50 species), lower in the Late Pennsylvanian (25–40 species) and the lowest in the Asselian (~ 20 species). The diversity in red bed intervals with poor preservation potential varies between 11 and 21 species. The two distinct habitat types, with high and low preservation potential, were dominated by different plant groups. Wetland habitats flourishing during the (per)humid to slightly seasonal intervals were colonized mainly by cryptogamic plants and some early gymnosperms, mainly pteridosperms and cordaitaleans. Habitats represented by red beds were dominated by cordaitaleans; from late Asturian time walchian conifers also occurred in these plant assemblages. However, conifers only became common in red beds in the Cantabrian. In the Saberian, conifers are rarely found in discrete beds associated with coal-bearing strata, however, their common occurrences start in lacustrine rocks of Asselian age. Temporal changes in vegetation patterns that show an increasing proportion of gymnosperms, in both wetland and dryland habitats are in agreement with the well known aridification trend in late Paleozoic tropical Pangea. Delays between the first appearance of walchian conifers in red beds (late Asturian) versus coal-bearing deposits (Saberian) supports the hypothesis that evolutionary innovations took place outside the windows of preservation, i.e. in well-drained, moisture-deficient areas. [ABSTRACT FROM AUTHOR]

A new assemblage of fossil beetles of Upper Pleistocene age, dated between 15,754 and 14,697 cal yr BP, is described and interpreted based on cluster analysis. In this study, we present an analysis on the taxonomic composition, and the paleoenvironmental implication of the fossil beetle assemblage in the archaeo- paleontological site of Pilauco in Osorno, south-central Chile (40°34′S-73°07′ W). Around 17,370 cal yr BP at the onset of deglaciation the old Damas River abandoned its alluvial plain; afterwards wetlands grew up by deposition of peat and colluvial sediments. The fossil beetles were deposited in the PB-7 layer where human artefacts and vertebrate remains have been found in the same spatial and temporal context. The assemblage includes 13 families, documented by 285 skeletal remains of fossil beetles. Ten ecological groups were identified and related to riparian, epigean, Nothofagus sp. forests, and lotic environments such as streams and ponds. Dung and fungi beetles were also part of the fossil assemblage. Pollen and carpological investigations in the same strata point towards the presence of wetlands and evergreen North Patagonian rainforest communities in the Pilauco site during the Upper Pleistocene. However, this study reveals that the Pilauco fossil beetles do not completely conform to any of the known modern assemblages. Therefore, we interpret that the fossil beetle assemblage from Pilauco is the result of the coexistence of different small pockets of habitats in a reduced spatial setting during a period of deep environmental/anthropic changes at the end of the last glaciation. The carabids and dung beetles from these beds indicate that the wetlands may have undergone dry conditions for undetermined periods of time. Finally, we compare nearly contemporaneous beetle assemblages of the sites Pilauco and Monte Verde II to discuss differences and similarities between the sites. [ABSTRACT FROM AUTHOR]

We here report on the systematics, paleoecology and biostratigraphy of a rare, but diversified gastropod fauna found in the early Pliocene sediments of the Agia Triada section in the Falanthi Basin (Peloponnese, Greece). Sixty-one species belonging to forty-eight genera are identified, allowing biostratigraphic assignment to the Mediterranean Plio-Pleistocene Molluscan Unit 1 (MPPMU1). Planktonic foraminiferal biostratigraphic analyses indicate that the Agia Triada section correlates with Zones MPL2 and MPL3, corresponding to the latest Zanclean. A comparison is further carried out between the studied assemblages and those previously documented from the Atlantic coasts of Europe and the Mediterranean region. New information on the palaeobiogeography of early Pliocene gastropod fauna is given, as seven species from the Mediterranean, thirty-nine species from the eastern Mediterranean and forty-four species from Greece, are documented here for the first time. [ABSTRACT FROM AUTHOR]

Many peatlands are exposed to intermittent burning but the implications of this burning for microbial communities have been little-studied. Here we consider the impacts of burning on the dominant protists of peatland ecosystems, the testate amoebae. To do this we used a ‘natural experiment’, a peatland exposed to wildfire where fire-fighting activity left a combination of unburned and heavily burned areas in close proximity. We assessed the change in testate amoebae three days after the end of the fire. We find that burning led to a large change in taxon composition, primarily noted by a shift from taxa with tests constructed of idiosomes to those constructed of xenosomes. The most likely explanation for this change is the direct destruction of mostly idiosome tests by extreme heat. Although we did not differentiate live individuals from empty tests it is probable that the fire led to a significant change in the testate amoeba community. This change may have interesting implications for the structure of microbial food webs, for biogenic silica cycling and for palaeoecological reconstruction in burned peatlands. This is clearly a topic which deserves more research attention. [ABSTRACT FROM AUTHOR]