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In the granitic part of the eastern Massif Central (France), the Gourd des Ailleres (GDA) mire provides one of the only Late-Glacial and Early Holocene sequences with a continuous sedimentation since the Oldest Dryas around 16000 years calibrated Before Present (16 ka cal. BP). Bioclimatic and hydrological changes were reconstructed based on sedimentological parameters, as well as by means of plant and animal macrofossils, pollen, and diatoms analyses through time. The environmental history of this site started with a small lake formed behind a moraine-dam. The multi-proxy study of the sedimentary sequence demonstrated that the coldest conditions took place around 14.3 ka cal. BP, at the very end of the Oldest Dryas. The Bolling period (14.2–13.9 ka cal. BP) was obviously warmer than the Allerod period (13.9–12.8 ka cal. BP) in the Monts du Forez Mountains. However, both chronozones presented a short cooling phase: the Intra Bolling Cold Period (IBCP) and the Intra Allerod Cold Period (IACP), respectively. The Older Dryas (14–13.9 ka cal. BP) was identified for the first time in this region based on pollen and diatom indicators. Thereafter, the Younger Dryas (12.9–11.7 ka cal. BP) was characterised by major temperature fluctuations. Windy conditions prevailed as indirectly demonstrated by the high frequency of Aulacoseira diatoms in the sequence. The onset of the Holocene was dated to 11.7 ka cal. BP. Peat-forming processes started thereafter due to the quick postglacial warming and the former GDA lake finally evolved into a limnogenous mire at the end of the Preboreal (10.4 ka cal. BP).

Detailed knowledge of the periglacial flora is essential to assess the vegetation dynamics in deglaciated regions of northern and north eastern Europe, previously covered by the ice sheet of the Late Weichselian Glaciation. Therefore, the territory of Belarus, which stretches in the periglacial zone of the Last Glaciation and the most part of which was free of ice during the Last Glacial maximum, is off particular importance in analysing the postglacial floral establishment and the subsequent vegetation dynamics in this part of the continent. In this study, results of palaeobotanical (pollen and plant macrofossil), lithological (measurements of magnetic susceptibility, MS) and isotopic (14C) investigations were obtained to fill the existing gap in reconstructing the peculiarities of the terrestrial and aquatic vegetation dynamics throughout the Lateglacial - Early Holocene period in the central Belarus. The investigated sediment profile, comprising organically enriched gyttja at 13,400–13,100 cal yr BP, carbon enriched and sandy gyttja at 13,100–9700 cal yr BP and unconsolidated mud after 9500 cal yr BP, provides clear evidence proving the flourishing of a pine-birch predominated forest with occasional spruce stands during the Allerod in area. Three occasions of change in the vegetation structure were noted within the Younger Dryas, i.e. 12,900–12,700 cal yr BP, 12,200–12,000 cal yr BP and 11,900–11,700 cal yr BP, suggesting negative climatic excursion taken place in area and facilitating flourishing of a Picea-predominating forest that culminated at about 12,300 and 12,000 cal yr BP. Pollen record suggests the Early Holocene vegetation shifts occurring at about 11,300–11,200 cal yr BP, 10,800–10,600 cal yr BP and 10,300–10,100 cal yr BP evidence the general response to the global-scale climatic events i.e. Preborael Oscillation or “10,2 ka” while fluctuations triggered by local or regional-scale climatic events have been identified as well. About 10,800–10,700 cal yr BP, formation of the forest with an increasing representation of thermophilous taxa (Ulmus, Tilia, Quercus) started in area.

Results of dendrochronological analysis of subfossil pine (Pinus sylvestris) buried in the Imszar raised bog deposits (NE Poland, Podlasie Region), were compared with multiproxy analysis of peat deposits (pollen and Non Pollen Palynomorphs, plant macrofossils, Cladocera, and geochemical analyses). The peat (3.3 m thick) accumulation started in the Allerod interstadial. The oldest pine tree population grew in this peatland in ca 6790–6530 cal yrs. BP: floating chronology (determined with the wiggle–matching method) covers this period is 255 years long. The growth of trees on the fen was related to the drying out of the fen at that time, which caused the break in peat accumulation (hiatus). Apart from numerous fallen trees excavated during the peat extraction, a horizon of vertical in situ tree trunks ingrown to the ground, were exposed during peat exploitation. On the basis of a dozen or so trees, a second, “dead forest” floating chronology 197 years long, was compiled with a time range of ca 4255-4060 cal yrs. BP. The youngest, third pine floating chronology (310 years long), elaborated on the basis of ex situ tree trunks, covers the time frame of ca 3130-2820 cal yrs. BP. Multiproxy analyzes of fen deposits indicate that the three stage colonization of the peatland by bog pine was associated with the periods of warming and overdrying in the climate of the Holocene, during which the groundwater table in the Imszar peatland significantly lowered. In turn, the dying off stages of the pine trees occurred in the phases of climate humidity growth, during which the groundwater level in the fen raised. They are well correlated with analogous bog pine germination and dying-off phases in the other European peatlands.

A multi-proxy study was performed on a gravity core supplemented by acoustics profiles and new radiocarbon dates of macrofossils found in the sedimentation history of the Odra Channel during the Holocene. The channel is located in the western part of Pomeranian Bay and was shaped by a pre-Odra river that flowed northwest along the Peene valley and the eastern part of Rugen Island during a drop in Yoldia Sea level. The acoustic profiling enabled identification of glacial till, the Baltic Ice Lake and Littorina sediments. The studied core penetrated only marine sediments deposited during Littorina and Post-Littorina stages and was the subject of grain size, geochemical and diatom analyses. The age of appearance of a marine environment in the studied area was estimated at 7200 yrs BP. The performed studies enabled division of the core into three phases of environmental evolution: the Littorina I phase occurred during the time span 7200–6000 yrs BP and is described as a shallow water brackish basin with a low rate of sea level rise and favourable conditions for biogenic production, the Littorina II phase dated at 6000–3800 yrs BP reflects a deep marine environment with relatively high salinity and greater current velocity, and the last phase, Post-Littorina, covered the last 3800 yrs BP and turned out to be a strongly energetic environment with decreasing salinity. The change from Littorina II to Post Littorina phase correlates clearly with a change in the acoustic reflection. Core analyses could be associated with extreme stormy cold events known as Bond events dated at 5900–5500 yrs BP and 4200 yrs BP evidencing the final destruction of the Odra Bank barrier.

Glacial lake sediments exposed at two sites in Skagit Valley, Washington, encase abundant macrofossils dating from 27.7 to 19.8 cal ka BP. At the last glacial maximum (LGM) most of the valley floor was part of a regionally extensive arid boreal (subalpine) forest that periodically included montane and temperate trees and open boreal species such as dwarf birch, northern spikemoss, and heath. We used the modern distribution and climate of 14 species in 12 macrofossil assemblages and a probability density function approach to reconstruct the LGM climate. Median annual precipitation (MAP) at glacial Lake Concrete (GLC) was ~50% lower than today. In comparison, MAP at glacial Lake Skymo (GLS) was only ~10% lower, which eliminated the steep climate gradient observed today. Median January air temperature at GLC was up to 10.8°C lower than today at 23.5 cal ka BP and 8.7°C lower at GLS at 25.1 cal ka BP. Median July air temperature declines were smaller at GLC (3.4°C–5.0°C) and GLS (4.2°C–6.3°C). Warmer winters (+2°C to +4°C) and increases in MAP (+200 mm) occurred at 27.7, 25.9, 24.4, and 21.2–20.7 cal ka BP. These changes accord with other regional proxies and Dansgaard–Oeschger interstades in the North Atlantic.

A new method of digital whitening of macrofossil images is based on the processing of a series of photographs of a fossil and represents a variation of the conversion photogrammetry method. It does not require 3-D modelling or specialized and expensive resources. The method is technically simple and fast. It has been tested on the imaging of large and medium-sized macrofossils, but it can also be used in the photography of small fossils, including microfossils.

The Devonian-Carboniferous transition is marked by major perturbations to the Earth’s climate system and marine redox conditions, a first-order mass extinction, and the succeeding marine ecosystem recovery, recording a sequence of environmental and biotic events. In South China, there exist numerous well-preserved and continuous Devonian-Carboniferous boundary successions that were formed in low-latitude passive margin basin, and this presents a unique opportunity to decipher the strata along a proximal to basinal transect using integrated biostratigraphical, event-stratigraphical, and geochemical approaches. Our geochemical data (δ13Ccarb, δ15Nbulk, δ238U and Mo/U enrichments, I/Ca ratio) indicated local and global C-N cycling perturbations and marine anoxia in the main phase of the Hangenberg Crisis interval (Middle Siphonodella praesulcata Zone), which coincided with a major regression in South China. Stromatoporoid biostromes and most typical Devonian faunas did not survive into the interval, and the deep-water black shales yield only opportunistic survivors, such as ammonoid Postclymenia cf. evoluta and bivalve Guerichina, along with miospores belonging to the LN Zone. The upper Hangenberg Crisis interval (Upper Si. praesulcata Zone, equal to the Protognathodus kockeli Zone) is marked by initial post-glacial transgression, a global δ13Ccarb spike, and opportunistic faunal blooms, coincident with conodont biofacies shift to the polygnathid-protognathodid biofacies. The Protognathodus fauna, nearly absent from platform facies, is often found in the condensed upper crisis interval of the basin, slope, and platform margin facies within the Youjiang Basin, although the abundance is extremely low and the phylogenetic lineage of Pr. meischneri-Pr. collinsoni-Pr. kockeli cannot be recognised in most successions. In South China, the first occurrence of Pr. kockeli seems to correspond to lithofacies changes, recorded in the first level of transgression just above the Hangenberg Sandstone event. Multiple lines of evidence, including great spatial heterogeneity of δ13Ccarb and δ15Nbulk records, extremes of redox proxies, and lack of macrofossils, suggest that marine habitats remained in a critical/turbulent state during the Upper Si. praesulcata Zone, triggering the opportunistic blooms and minor extinctions. Following the crisis intervals, radiation/recovery of many fossil groups did not occur until the upper part of the Siphonodella sulcata Zone to the Si. duplicata Zone. In particular, a negative shift of δ13Ccarb to pre-crisis values occurring near the base of the Si. sulcata/Pr. kuehni Zone could be recognised worldwide. The research history, current status, and achievement of Devonian-Carboniferous boundary in China are briefly reviewed.

Purpose The analysis of n-alkanes in palaeoenvironmental studies of peatlands is mainly limited to ombrogenous peatlands which are a rare feature in the environment. Using n-alkane and plant macrofossil analysis, we have tracked changes in the environment in the valley of a large Central European river. We tested the possibilities for applying such studies to low-moor bogs which are the most commonly occurring type of bog in the world. Materials and methods Representative peat samples were taken from two profiles in a peatland located in the Vistula Valley (southern Poland), and they were analysed for the occurrence and distribution of biomarkers. The distribution of n-alkanes was determined using gas chromatography-mass spectrometry (GC–MS). The botanical composition of the samples was determined by analysis of plant macrofossil remains, and the degree of peat decomposition was also determined. Results and discussion Samples of low-moor peat were characterised by a prevalence of medium- and long-chain n-alkane homologues, which is typical for higher plants. The variable values of the CPI, CPI (25–31), and the C23/C25 ratio have provided information on the stages of formation of the Zapadź bog. The source of n-alkane differentiation is vegetation change related to palaeohydrological dynamics and palaeoenvironmental conditions within the peatland. Conclusions We have shown that analysis of n-alkanes can be successfully used in low-moor bogs as a complement to palaeobotanical and palaeozoological methods. The bringing together of these types of research enables changes in the ecosystems of large river valleys to be tracked.

Lacustrine sediments have the potential to preserve paleoenvironmental proxies such as terrestrial plant waxes at high temporal resolution. The temporal fidelity of plant wax records, however, can be up to several thousand years older than the corresponding sediment, based on compound-specific radiocarbon (14C) analysis. Unfortunately, the factors controlling 14C age offsets between plant waxes and sediments are not well understood. The aims of this study are to quantify and compare plant wax n-alkane 14C age offsets among lakes within the same region, and to determine if drainage and lake basin differences (e.g., size, relief, drainage basin morphology, fluvial inputs) influence these offsets. We collected sediments from five lakes in the Adirondack Mountains, NY, USA that lack petrogenic sources of n-alkanes, and range in drainage basin characteristics. Sediment age models were constructed for each lake using a combination of sediment 210Pb, 137Cs, and macrofossil 14C ages, and compared to 14C ages of long-chain (n-C27, n-C29, n-C31) alkanes sampled from Holocene and Late Glacial aged sediments. The n-alkane 14C ageinitial is a measure of the age offset in n-alkanes relative to the sediment they are deposited in. Across all lakes, the n-alkane 14C ageinitial ranged from penecontemporaneous to 2440 14C yr. This oldest n-alkane 14C ageinitial is significantly outside the distribution of all other samples; when excluded, the overall mean n-alkane 14C ageinitial was 400 ± 255 14C yr (n = 23). The largest n-alkane 14C ageinitial values were observed in the last 1 cal kyr BP (565 ± 180 14C yr (1σ), n = 12)) compared to sediments deposited between 1 and 13 cal kyr BP (220 ± 195 14C yr (1σ), n = 11)). These age offsets develop early after initial lake basin sedimentation and follow a similar pattern in all of the lakes despite differences in lake basin and catchment size, relief, and geomorphology. We speculate that 14C age offsets occur due to reworking of older n-alkanes stored in drainage basin sediments and soils and this mechanism is most effective in the last ∼1 kyr. Regardless, lakes in temperate forested metamorphic bedrock terrains have relatively small and stable n-alkane age offsets compared with lakes with extensive catchment soils or anthropogenic disturbance. By targeting lakes with minimal catchment soils, age offsets may be reduced, thereby minimizing attenuation or age distortion of climate signals in plant wax isotopic records.

The article reports a dispersed megaspore morphotaxon, Biharisporites Potonie for the first time from the Nidpur beds, Madhya Pradesh, India. The megaspores are structurally preserved compressions and reveal the presence of lycopsids in the parent flora, though macrofossil evidence of such plants is almost lacking. The diagnosis of Biharisporites is emended, to include all externally similar cavate spore types, irrespective of whether their inner sac/nexine/inner body/mesosporium/inner exospore, is pitted/cushioned or unpitted. The megaspores assigned to the genus are represented by two new species, viz., Biharisporites gopalii sp. nov. and B. bosei sp. nov. They are rare, non-lageniculate, trilete megaspores having spinae or coni on both proximal and distal surfaces. Though the early Triassic has traditionally been interpreted as semi-arid, the recovery of carbonaceous debris from the non-coal bearing Nidpur beds suggests a favourable climate for vegetation in the middle Triassic (Anisian-Ladinian) at the time of deposition of plant debris.

Herbivory is a common ecological function among extant lepidosaurs, but little is known about the origin of this feeding strategy within Lepidosauria. Here we describe a sphenodontian (Lepidosauria) from the Late Triassic of western North America, Trullidens purgatorii n. gen. n. sp., that reveals new aspects of the earliest radiation of herbivorous lepidosaurs. This taxon is represented by an isolated lower jaw with robust structure bearing transversely widened dentition and extensive wear facets, suggesting a masticatory apparatus specialized for herbivory. An unusual 'incisor-like' tooth is present at the anterior end of the jaw; a unique feature among lepidosaurs, this tooth is convergent with the incisors of extant rodents and lagomorphs. Phylogenetic analyses support the placement of this taxon within opisthodontian sphenodontians, a group sharing derived cranio-dental morphologies specialized for herbivory. The new taxon was recovered in a recently discovered and unnamed series of Upper Triassic strata in southeastern Colorado, USA, exposed in Canyons incised by the Purgatoire River and its tributaries. These strata comprise a dominantly red-bed sequence of conglomerates, sandstones, and siltstones deposited in a fluvio-lacustrine setting, preserving a Late Triassic biota of invertebrate and vertebrate ichnofossils, plant macrofossils, bony fish, temnospondyl amphibians, and reptiles. We use aetosaur osteoderms as biostratigraphic links to the nearby Chinle Formation of Arizona, USA, establishing a middle Norian age for these strata. The presence of an opisthodontian from western equatorial Pangaea in the Norian Stage reveals a near-global radiation of this clade across the Pangaean supercontinent during the Late Triassic. UUID: http://zoobank.org/A737c03f-863a-488e-a860-5cc914548774. Virginia Tech Paleobiology Group Published version M.R. Stocker and S.J. Nesbitt of the Virginia Tech Paleobiology Group provided funding for and conducted mu CT scanning, which was conducted at the Duke Shared Instrumentation Facility and facilitated by J. Gladman. J. Autry, the Southeast Colorado Project Director at The Nature Conservancy, facilitated access to the J.E. Canyon Ranch and provided logistical support, supplies, and housing for the authors. B. Preston, S. Korbitz, B. Small, and Y. Huang assisted in field work. The Virginia Tech Paleobiology Research Group provided useful critiques and suggestions for figures in the manuscript. M. R. Stocker provided useful critiques and discussions on the manuscript. W.G. Parker of Petrified Forest National Park provided assistance in identifying aetosaur osteoderms. K. MacKenzie and J. Sertich of the DMNH facilitated curation of specimens used in this study. B. Creisler provided valuable etymological assistance. D. Whiteside and an anonymous reviewer provided valuable reviews of the manuscript. Public domain – authored by a U.S. government employee

In the Estepona basin (Málaga, S Spain), the richest and the most diverse Pliocene sites of marine invertebrates (mostly molluscs) of the Mediterranean are found. Most of the species described up until now (~95% out of 892 identified species) occur at the Parque Antena and the Velerín Area (Velerín, Velerín-Carretera and Velerín-Antena) sites. Although molluscs are very well known, the age of these important sites is still controversial. In this paper, a biochronological study of these sites based on an integrated study of the microfossil (calcareous nannoplankton and planktonic foraminifers) and macrofossil (molluscs) assemblages is presented. The Parque Antena and Velerín-Carretera sites can be attributed to the late Zanclean (uppermost part of the early Pliocene) based on the presence of Globorotalia margaritae, Gr. puncticulata and Gr. group crassaformis (including Gr. crassaformis s.s.). Nannoplankton assemblages agree with this age, and can be attributed to the CN11b biozone of Okada & Bukry (1980) due to the presence of small Gephyrocapsa, Sphenolithus abies and Reticulofenestra pseudoumbilica. At the Velerín-Antena section, the bioindicators of the early Pliocene Gr. margaritae, Sphenolithus abies and Reticulofenestra pseudoumbilica are absent. The molluscs found in the studied sites correlate with the Mediterranean Pliocene Molluscan Unit 1 of Raffi & Monegatti (1993) (MPMU1). Finally, the coexistence of Gr. margaritae and Gr. group crassaformis in the Mediterranean domain is described for the first time.

Siberian larch (Larix Mill.) forests dominate vast areas of northern Russia and contribute important ecosystem services to the world. It is important to understand the past dynamics of larches in order to predict their likely response to a changing climate in the future. Sedimentary ancient DNA extracted from lake sediment cores can serve as archives to study past vegetation. However, the traditional method of studying sedimentary ancient DNA - metabarcoding - focuses on small fragments which cannot resolve Larix to species level nor allow a detailed study of population dynamics. Here we use shotgun sequencing and hybridization capture with long-range PCR-generated baits covering the complete Larix chloroplast genome to study Larix populations from a sediment core reaching back to 6700 years from the Taymyr region in northern Siberia. In comparison to shotgun sequencing, hybridization capture results in an increase of taxonomically classified reads by several orders of magnitude and the recovery of complete chloroplast genomes of Larix. Variation in the chloroplast reads corroborate an invasion of Larix gmelinii into the range of Larix sibirica before 6700 years ago. Since then, both species have been present at the site, although larch populations have decreased with only a few trees remaining in what was once a forested area. This study demonstrates for the first time that hybridization capture applied directly to ancient DNA of plants extracted from lake sediments can provide genome-scale information and is a viable tool for studying past genomic changes in populations of single species, irrespective of a preservation as macrofossil. published

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UV-light-induced fluorescence is widely used in the study of coal macerals and palynological samples, but to date has not been described in great detail for plant macrofossils. Here, we report the characteristics of bright UV-light-induced fluorescence of various fossil angiosperm leaf taxa from the Upper Pliocene of Willershausen, Lower Saxony, Germany. The fluorescence is exceptional, since different fluorescence colors ranging from green to yellow to red can be observed and fluorescence properties are found to be related to genera. Using confocal laser scanning microscopy, fluorescence was studied in detail and emission spectra were obtained that allowed to differentiate broad groups of fluorophores. Fluorescence emissions attributed to chlorophyll degradation products demonstrate that fluorescence can be used as an indicator for exceptional chemical preservation of leaf fossils. Comparison with present-day senescing plants suggests that the fluorescence differences in the fossil leaves are mainly caused by taxon-specific degeneration of organic compounds during senescence. The occurrence of various leaf taxa with different fluorescence properties, preserved under identical conditions of fossilization, indicate that diagenesis was not crucial for the differences in leaf fluorescence.

Potential Last Glacial Maximum (LGM, 26,500–15,000 bp) members of the Eastern Beringia (now Alaska-Yukon, northwest North America) vascular flora were recognized based on their contemporary co-occurrence in easternmost Siberia (formerly part of Western Beringia). Of 1,633 indigenous terrestrial Alaska-Yukon taxa, 835 also occur in easternmost Siberia, including 526 arctic/alpine and 90 subarctic taxa. Archival macrofossil and DNA evidence corroborated the occurrence of 55 LGM taxa and indicated the presence of an additional 13 non–Western Beringian taxa. The total (848) was double the number of taxa previously considered amphi-Beringian, but likely, still an underestimate. Most Eastern Beringian arctic/alpine and subarctic taxa were perennials (94%) and forbs (64%), with herbaceous plants having average median heights of ≤ 37 cm. Arctic/alpine taxa were associated with xeric to submesic environments (54%), whereas the subarctic taxa favoured moister conditions. Both arctic/alpine and subarctic taxa were potentially present in unglaciated Eastern Beringia. However, some subarctic taxa may have migrated from refugial areas peripheral to Western Beringia during the Late Wisconsinan, prior to opening of the Bering Strait (11,000 bp), rather than being migrants from mid-latitude North America because of timing and distance considerations. Currently, former LGM Eastern Beringian taxa dominate (> 80% content) the flora and plant canopy cover of Alaska-Yukon arctic vegetation, but their frequency decreases curvilinearly (~ 0.102 taxon km−1) from Alaska to Hudson Bay, and from Yukon to southern British Columbia (p 1,400 km from Eastern Beringia.

Annulated discoidal structures are common in many Neoproterozoic and particularly Ediacaran successions. Their interpretations, especially their biogenicity, are often contentious. Some of them (e.g., Aspidella and related forms) are demonstrably biological structures and may represent holdfasts of frondose Ediacara-type organisms. Others may represent fluid escape structures or tool marks produced by the rotation of tethered organisms. Here we show that differential chemical weathering of diagenetic dolomite concretions can also produce annulated discoidal structures that could be mistaken as Ediacara-type discoidal fossils. Using transmitted-light and cathodoluminescence microscopy in conjunction with Raman and energy dispersive spectroscopy, we analyzed dolomitized discoidal concretions embedded in a phosphorite matrix from the Ediacaran Miaohe Member of South China. Our observations reveal that pervasive and displacive syn-compactional dolomitization of the concretions and differential compaction of surrounding sediment led to the formation of biconvex or upward-convex primary laminae within the concretions. When exposed along parting surfaces and/or bedding planes, disparities in the weatherability of the warped primary laminae within the concretions resulted in the formation of circular annuli that mimic Neoproterozoic discoidal structures, some of which have been contentiously interpreted as discoidal fossils. These findings emphasize the importance of thin-section petrographic observations in the study of discoidal dubiofossils in order to assess their origin as diagenetic concretions or as discoidal macrofossils.

The study of faecal samples to reconstruct the diets and habitats of extinct megafauna has traditionally relied on pollen and macrofossil analysis. DNA metabarcoding has emerged as a valuable tool to complement and refine these proxies. While published studies have compared the results of these three proxies for sediments, this comparison is currently lacking for permafrost preserved mammal faeces. Moreover, most metabarcoding studies have focused on a single plant-specific DNA marker region. In this study, we target both the commonly used chloroplast trnL P6 loop as well as nuclear ribosomal ITS (nrITS). The latter can increase taxonomic resolution of plant identifications but requires DNA to be relatively well preserved because of the target length (∼300–500 bp). We compare DNA results to pollen and macrofossil analyses from permafrost and ice-preserved faeces of Pleistocene and Holocene megafauna. Samples include woolly mammoth, horse, steppe bison as well as Holocene and extant caribou. Most plant identifications were found using DNA, likely because the studied faeces contained many vegetative remains that could not be identified using macrofossils or pollen. Several taxa were, however, identified to lower taxonomic levels uniquely with macrofossil and pollen analysis. The nrITS marker provides species level taxonomic resolution for commonly encountered plant families that are hard to distinguish using the other proxies (e.g. Asteraceae, Cyperaceae and Poaceae). Integrating the results from all proxies, we are able to accurately reconstruct known diets and habitats of the extant caribou. Applying this approach to the extinct mammals, we find that the Holocene horse and steppe bison were not strict grazers but mixed feeders living in a marshy wetland environment. The mammoths showed highly varying diets from different non-analogous habitats. This confirms the presence of a mosaic of habitats in the Pleistocene ‘mammoth steppe’ that mammoths could fully exploit due to their flexibility in food choice.

A system of farming with an alternation of land use between being cultivated or left fallow as grassland (Feldgraswirtschaft) developed in southwestern Germany since the Bronze Age. It involved fallow periods, where the arable land is left without crops in order to let it recover its fertility for several years while becoming grassland. This led to regeneration of the topsoil humus, which could later be mobilized by cultivation. With later farming systems, the supply of nutrients needed for crops could also be provided by manuring, which allowed shorter fallow periods but required the production of manure. Such cultivation systems with short or even without fallow phases and with intensive manuring are known from the medieval period as one, two or three field systems of agriculture and their development was an important step towards the intensification of farming. The current study considers on-site plant macrofossil data from archaeological sites as well as the off-site pollen data from cores in Baden-Württemberg in order to recognize the main changes towards agricultural intensification through time from the Bronze Age up to medieval times. The various landscape types included in the study area also reveal their different agricultural histories of intensification. In lowlands with good soils, the intensification can be recognized earlier and more strongly than in uplands or other marginal areas. The main shift towards intensification took place in the Roman period, which is also confirmed by written sources of the time that mention manuring as well as a kind of two field system and alternation between grassland and arable land.

This study presents the first report of angiosperm macrofossil assemblage from the Early Cretaceous sediments of India, containing a fruit, a spike, a petal, leaves, and an axis from the Krishna Godavari Basin. This assemblage provides clues to angiosperm evolution and ecology during the Early Cretaceous of India. The described enigmatic forms are comparable to fruits of Trapa, and palm leaves and spikes of Potamogeton. The fossil material also includes ribbon-like leaves with a small axis; fossil remains suggest affinity with the monocotyledon group and support recent morphological and molecular phylogenetic studies to establish the divergence of this group from dicotyledons, during the early Cretaceous. Fossils described in the present study suggest an affinity for an aquatic environment that appears to be ideal for some early angiosperms.

Examination of macrofossils from the late Neogene Pipe Creek Sinkhole in Indiana, USA, yielded 15 distinct plant taxa, one fungal taxon, and six invertebrate taxa. The plant assemblage was dominate...

Age assessments from both palynostratigraphy and macrofossil biostratigraphy of the sandstone-dominated Mågensfjeld Formation, Wandel Sea Basin, North Greenland were hitherto hampered by post-burial thermal degradation of dinoflagellate cysts and a lack of well-preserved macrofossils. The formation was previously assigned to the Upper Cretaceous based on erroneous fossil identifications. Finds of cardioceratid and kosmoceratid ammonites during recent field work now provide the first age control of the unit, demonstrating it to be of late Bajocian – late Bathonian and perhaps Callovian (Middle Jurassic) age. This makes it among the oldest Jurassic units, perhaps even Mesozoic units, recorded in Kilen, North Greenland and eastern North Greenland. Previously, the complex structural and tectonic evolution of the area was poorly understood, and the structural relation of the Mågensfjeld Formation to the surrounding Mesozoic units was a puzzle. The new age assessment simplifies the structural situation in the area significantly. Further, the inference of a large reverse fault previously required to explain the proximity of the Mågensfjeld Formation to neighbouring Jurassic units is now unnecessary. The data show that the Wandel Sea Basin was influenced by the Middle Jurassic transgression and had sufficient accommodation space for marine deposition earlier than previously thought. The unit serves as a key datapoint and analogue for possible Middle Jurassic units in adjacent offshore basins.

The fluvial facies of the Catskill Formation record important ecological events that occurred during Late Devonian time. A well-exposed section between the towns of Blossburg and Covington, in north-central Pennsylvania, contains abundant macrofossils and sedimentary features, making it well-suited for linking Upper Devonian fossil occurrences with depositional environments and sedimentary processes. Strata consist of two distinct fluvial facies: floodplain lithofacies consist of mudrocks, with evidence of pedogenic overprinting and sharp-based sandstones interpreted as crevasse splays; channel-bar lithofacies consist of single- and multi-storied cross-stratified lenticular sandstone bodies interpreted as fluvial channel-bar complexes. Macrofossils occur in 22 discrete horizons spanning > 240 m of stratigraphic succession that include Archanodon bivalve shell impressions, two genera of “placoderms” (Bothriolepis, Phyllolepis), an unidentified acanthodian, and several taxa of sarcopterygian fishes, including lungfish (Dipnoi indet.), Holoptychius, Langlieria, and Sauripterus. Most vertebrate macrofossils are preserved as disarticulated, abraded plates, scales, and bone fragments in sandstone channel-bar deposits. Articulated, unabraded remains are preserved in proximal floodplain deposits. Miospores recovered from Catskill Formation fossil sites in the Blossburg-Covington section belong to the COR subzone of the VCo (Diducites versabilis-Grandispora cornuta) palynological zone, indicating deposition ca. 362 to 361.8 Ma during the late Famennian stage of the Late Devonian. Catskill Formation fluvial strata exposed tens of kilometers to the south and west yield latest Famennian palynomorphs. These broadly contemporaneous continental depositional environments supported Late Devonian vertebrate evolution, including the fin-to-limb transition in tetrapodomorphs, and the possible euryhalinity of vertebrates occupying marine-to-nonmarine transitional habitats.

Deposits of at least three glaciations are present in New Jersey and the New York City area. The oldest deposits are magnetically reversed. Pollen and stratigraphic relations suggest that they are from the earliest Laurentide advance at ~2.4 Ma. Deposits of a second advance are overlain by peat dated to 41 ka and so are pre-Marine Isotope Stage (pre-MIS) 2. Their relation to marine deposits indicates that they predate MIS 5 but postdate MIS 11 and may postdate MIS 7 or 9, suggesting an MIS 6 age. The most recent deposits are of MIS 2 (last glacial maximum [LGM]) age. Radiocarbon dates and varve counts tied to glacial-lake events indicate that LGM ice arrived at its terminus at 25 ka, stood at the terminus until ~24 ka, retreated at a rate of 80 m/yr until 23.5 ka, and then retreated at a rate of 12 m/yr to 18 ka. At 18 ka the retreat record connects to the base of the North American Varve Chronology at Newburgh, New York. The 25–24 ka age for the LGM is slightly younger than, but within the uncertainty of, cosmogenic ages; it is significantly older than the oldest dated macrofossils in postglacial deposits in the region.

Six Tsuga ovuliferous/seed cone impression fossils were discovered from the late Eocene (34.6 ± 0.8 Ma) Lawula Formation in Mangkang County, eastern Tibet and the early Oligocene (32 ± 1 Ma) lacustrine deposits in Luhe Basin, Nanhua County, Yunnan Province. These two fossil sites are both located in southwestern China, ∼800 km apart from each other. These fossils represent the oldest records of this genus in southwestern China, even earliest reliable macrofossil records of this genus in the world. These well-preserved seed cones provide sufficient materials for the establishment of Tsuga asiatica Wu et Zhou n. sp. to accommodate five specimens, leaving one to be assigned to T. cf. dumosa Eichler (cf. Wu et Zhou). Both qualitative and quantitative comparisons with other cone fossils and cones of all living species of the genus suggested that T. asiatica shares more similarities with one of the basal species of the genus T. heterophylla. The discovery of late Paleogene macrofossil records of Tsuga in southwestern China supports the previous hypothesis of the early disposal routes of this coniferous genus predicted by phylogenetic analysis. The elevation ranges and the climate requirements of living species that are closely related to our fossils suggest that the southeastern edge of the Qinghai-Tibetan Plateau should be much warmer, and wetter in late Paleogene than nowadays.

Author(s): Surprenant, Rachel Lorraine | Advisor(s): Droser, Mary | Abstract: The Ediacara Biota represent a turning point in the evolution of life on Earth, signifying the transition from single celled organisms to complex, community forming macrobiota. The exceptional fossil record of the soft-bodied Ediacara Biota provides critical insight into the nature of this transition and into ecosystem dynamics leading up to the so-called “Cambrian Explosion”. However, the preservation of non-biomineralizing organisms in a diversity of lithologies goes hand-in-hand with considerable taphonomic complexity that often shrouds true ecological and biological signatures. We address the nature of this taphonomic complexity within the fossiliferous sandstones of the Ediacara Member in South Australia. Utilizing the most data-rich and well-preserved outcropping of the Ediacara Member, the Nilpena Station National Heritage Ediacara Fossil Site, we conduct a focused, taxon-level taphonomic characterization of the tubular organism Funisia dorothea. Funisia is the most abundant body fossil in the Ediacara Member, making its taphonomic characterization essential to the accurate interpretation of regional paleobiology and paleoecology. We identify two primary modes of Funisia population structure, cluster-type and surface-type packages, each of which exhibit distinct suites of taphonomic variation in individual Funisia. Within the two package types, four preservational modes of Funisia are identified: convex external molds, concave external molds, convex internal molds, and concave internal molds. Among macrofossils at Nilpena, this tiered preservational complexity is unique to Funisia; its systematic classification elucidates population-level biostratinomy at Nilpena as well as aspects of Funisia’s paleobiology and autecology.

During the early Eocene, Patagonia had highly diverse floras that are primarily known from compression and pollen fossils. Fossil wood studies from this epoch are scarce in the region and largely absent from the Laguna del Hunco flora, which has a highly diverse and excellently preserved compression assemblage. A collection of 26 conifer woods from the Laguna del Hunco fossil-lake beds (early Eocene, ca. 52 Ma) from central-western Patagonia was studied, of which 12 could be identified to genus. The dominant species is Phyllocladoxylon antarcticum, which has affinity with early-diverging Podocarpaceae such as Phyllocladus and Prumnnopitys. A single specimen of Protophyllocladoxylon francisiae probably represents an extinct group of Podocarpaceae. In addition, two taxonomic units of cf. Cupressinoxylon with putative affinity to Podocarpaceae were found. Diverse Podocarpaceae taxa consistent with the affinities of these woods were previously reported from vegetative and reproductive macrofossils as well as pollen grains from the same source unit. Some of the woods have galleries filled with frass. Distinct growth ring boundaries indicate seasonality, inferred to represent seasonal light availability. Growth ring widths suggest that the woods came from mature trees, whereas the widths and types of some rings denote near-uniform temperature and water availability conditions. Fil: Pujana, Roberto Roman. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Museo Argentino de Ciencias Naturales "Bernardino Rivadavia"; Argentina Fil: Wilf, Peter. State University of Pennsylvania; Estados Unidos Fil: Gandolfo, María Alejandra. Cornell University; Estados Unidos