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  • 1. Bajdek, Piotr
    et al.
    Owocki, Krzysztof
    Niedzwiedzki, Grzegorz
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Organismal Biology.
    Putative dicynodont coprolites from the Upper Triassic of Poland2014In: Palaeogeography, Palaeoclimatology, Palaeoecology, ISSN 0031-0182, E-ISSN 1872-616X, Vol. 411, p. 1-17Article in journal (Refereed)
    Abstract [en]

    A significant number (more than 100) of brownto dark and silty, carbonate or pyrite-mineralized, in part organic carbon-rich, spherical or oval-shaped structures have been collected fromthe Upper Triassic (uppermost NorianlowerRhaetian) sediments of the Lipie Śląskie clay-pit at Lisowice near Lubliniec town, Poland. Their geological context, morphology, content, geochemistry and association with skeletal remains suggest they are fecal masses of a sizable herbivorous tetrapod. The only large herbivore known from the site is a giant 5 meter-long dicynodont (Synapsida: Anomodontia), represented by numerous bones and also by large, oval-shaped footprints. The putative dicynodont coprolites were collected from mudstone and siltstone with numerous organic remains that were deposited in anoxic conditions. In addition, REEs and other trace element concentrations suggest that the burial environment and diagenesis of these coprolites were under anoxic conditions. SEM and thin section images of the coprolite matrix show numerous nests with pyrite (probably bacterial in origin) and large amount of mineral particles. The putative dicynodont coprolites contain also amorphous, dark organic matter, poorly preserved palynomorphs, small fragments of plant cuticle. Detailed characteristic of these coprolites reveals possible implications for the ecology and physiology of the source animal species. The δ 13C values of the gymnospermcuticle and dark organic matter measured in three coprolites are −23.4‰, −21.2‰and −20.3‰, all average. The evidence from these coprolites suggests that dicynodonts processed plant soft elements into very small pieces, but wood fragments were found also in a mass accumulation in two coprolites.

  • 2.
    Bajdek, Piotr
    et al.
    Aleja Najswietszej Maryi Panny 20-20A, PL-42200 Czestochowa, Poland..
    Owocki, Krzysztof
    Polish Acad Sci, Inst Paleobiol, Twarda 51-55, PL-00818 Warsaw, Poland..
    Sennikov, Andrey G.
    Russian Acad Sci, Borissiak Paleontol Inst, Profsoyuznaya 123, Moscow 117997, Russia.;Kazan Fed Univ, Kremlyovskaya 18, Kazan 420008, Russia..
    Golubev, Valeriy K.
    Russian Acad Sci, Borissiak Paleontol Inst, Profsoyuznaya 123, Moscow 117997, Russia.;Kazan Fed Univ, Kremlyovskaya 18, Kazan 420008, Russia..
    Niedzwiedzki, Grzegorz
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Organismal Biology, Evolution and Developmental Biology.
    Residues from the Upper Permian carnivore coprolites from Vyazniki in Russia - key questions in reconstruction of feeding habits2017In: Palaeogeography, Palaeoclimatology, Palaeoecology, ISSN 0031-0182, E-ISSN 1872-616X, Vol. 482, p. 70-82Article in journal (Refereed)
    Abstract [en]

    Residues of twenty-five coprolite fragments collected from the Upper Permian of Vyazniki (European Russia) were studied in detail. The phosphatic composition, general shape and size, and bone inclusions of these specimens indicate that medium to large-sized carnivores, such as therocephalian therapsids or early archosauriforms, were the most likely coprolite producers. The contents of the examined fossils (i.e. Scale, bone and tooth fragments, mineral grains, and microbial structures) do not differ significantly among the samples, implying fairly comparable feeding habits of their producers. Fragments of large tooth crowns in two of the analyzed samples imply that either (1) the coprolite producer swallowed the cranial elements of its prey or (2) the coprolite producer broke and swallowed its own tooth while feeding (such tooth damage is known in archosaurs that have tooth replacement, e.g. crocodiles and dinosaurs). Indeed, the most complete tooth fragment in these fossils is serrated, most likely belonging to an early archosauriform known from skeletal records from the Late Permian of Vyaznilci. Another coprolite fragment contains the etched tooth of a lungfish, while putative actinopterygian fish remains (scales and small fragments of bones) are abundant in some samples. Mineral particles (mostly quartz grains, feldspars and mica) may have been swallowed accidentally. The preserved microbial colonies (mineralized fossil fungi and bacteria or their pseudomorphs), manifested in the coprolites as Fe-rich mineral structures, seem to have developed on the expelled feces rather than on the items before they were swallowed.

  • 3. Bird, Anna
    et al.
    Stevens, Thomas
    Department of Geography, Royal Holloway University of London, UK.
    Rittner, Martin
    Vermeesch, Pieter
    Carter, Andrew
    Andò, Sergio
    Garzanti, Eduardo
    Lu, Huayu
    Nie, Junsheng
    Zeng, Lin
    Zhang, Hanzhi
    Xu, Zhiwei
    Quaternary dust source variation across the Chinese Loess Plateau2015In: Palaeogeography, Palaeoclimatology, Palaeoecology, ISSN 0031-0182, E-ISSN 1872-616X, Vol. 435, p. 254-264Article in journal (Refereed)
  • 4.
    Brown, Caleb M.
    et al.
    Tyrrell Museum of Paleontology.
    Evans, David C.
    Royal Museum of Nature.
    Campione, Nicolas E.
    Department of Ecology and Evolutionary Biology, University of Toronto, Toronto, Canada.
    O'Brien, Lorna J.
    University of Toronto.
    Eberth, David A.
    Tyrrell Museum of Paleontology.
    Evidence for taphonomic size bias in the Dinosaur Park Formation (Campanian, Alberta), a model Mesozoic terrestrial alluvial‐paralic system2013In: Palaeogeography, Palaeoclimatology, Palaeoecology, ISSN 0031-0182, E-ISSN 1872-616X, Vol. 372, no SI, p. 108-122Article in journal (Refereed)
    Abstract [en]

    A study of the distribution of dinosaurian body masses in the Dinosaur Park Formation (DPF; Campanian; southern Alberta), reveals a prominent negative skew; a pattern distinct from those of modern terrestrial faunas. We find a direct and robust correlation between taxon size (estimated live body mass) and known completeness. There is a clear dichotomy between large and small-bodied taxa at around 60 kg, in which taxa less than 60 kg are significantly less complete (mean completeness = 7.6%) than those with an estimated mass of 60 kg or greater (mean = 78.2%). Along with completeness, there is also a strong association of body size and taphonomic mode, with small taxa known largely from isolated and occasionally associated remains, and large taxa known from articulated skeletons. In addition, there is a significant correlation between taxon body mass and both date of discovery and of description, with taxa < 60 kg taking an average of 65.9 and 75.6 years to discover and describe, respectively, compared to 33.6 and 34.1 years for taxa > 60 kg. The rates of both cumulative discovery and description for large taxa are best described by a logarithmic curve nearing an asymptote, whereas small taxa show either a linear or power increase through time. This suggests that our current knowledge of the large-bodied dinosaur assemblage is reasonably representative of the true biological fauna with few discoveries likely to be made in the future. However, small taxa are greatly underestimated in both their diversity and abundance, with many more potential discoveries to be made. Given that (1) the sedimentary deposits and fossil assemblages in the DPF together represent one of the best studied examples of a Mesozoic alluvial‐paralic (terrestrial) ‘palaeoecosystem,’ and (2) similar patterns have been suggested (but not documented) for other Mesozoic terrestrial ecosystems in the Western Interior of North America, we suggest that this pattern of size bias may typify vertebrate fossil assemblages in terrestrial Mesozoic systems. If so, such biases must be considered before patterns of diversity in dinosaur communities through time can be considered accurate, or used to compare and interpret Mesozoic palaeoecosystems.

  • 5. Chen, Junyuan
    et al.
    Waloszek, Dieter
    Maas, Andreas
    Braun, Andreas
    Huang, Diying
    Wang, Xiuqiang
    Stein, Martin
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, Palaeobiology.
    Early Cambrian Yangtze Plate Maotianshan Shale macrofauna biodiversity and the evolution of predation2007In: Palaeogeography, Palaeoclimatology, Palaeoecology, ISSN 0031-0182, E-ISSN 1872-616X, Vol. 254, no 1-2, p. 250-272Article, review/survey (Refereed)
    Abstract [en]

    The large number of soft-part preserved fossils from the Lower Cambrian Maotianshan Shale (Chengjiang) Lagerstätten suggests particularly favourable conditions for a rich life on the shelf-zone sea bottom of the Yangtze Plate, China. This high degree of biodiversity opens an excellent window into the early radiation phase of Metazoa and represents a significant data source for the study of adaptive strategies among early animals. Feeding and locomotion are the main life strategies of organisms we investigated with regard to two major benthic macrofaunal components of the Maotianshan Shale biota, the nemathelminths and the arthropods. Our attempt was to test whether food, feeding and locomotory strategies of the benthic Lower Cambrian shallow-water communities were as diversified as it appears from the morphological diversity of the organisms present. Two major types of feeders can be discerned: suspension/micro-particle feeders – mostly epibenthic sedentary taxa – and larger-particle feeders, living in benthic to bentho-pelagic realms. Scant evidence exists for exclusive vegetarians, fungi eaters, biomat utilizers and for in-faunal vertical burrowers or grazers (bioturbators). Predation, in a wider sense, seems to be a, if not the, major feeding mode among metazoans. Nemathelminths and arthropods are amongst the best examples. In the benthic shallow-water regime, as exposed by the Maotianshan Shale biota, animals and their ontogenetic stages were the most suitable and readily available food source. At least for arthropods, we propose that improvement of predatory strategies was paralleled by the enhancement of locomotory and food manipulation structures. Accumulating evidence of late Precambrian to Early Cambrian metazoans exposing diverse morphologies and life styles indicates that, on the large scale, phylogenesis progressed gradually in the Late Precambrian. This renders an “explosive” radiation of Metazoa unlikely.

  • 6. Cobianchi, M.
    et al.
    Mancin, N.
    Lupi, C.
    Bordiga, Manuela
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, Palaeobiology.
    Bostock, H. C.
    Effects of oceanic circulation and volcanic ash-fall on calcite dissolution in bathyal sediments from the SW Pacific Ocean over the last 550 ka2015In: Palaeogeography, Palaeoclimatology, Palaeoecology, ISSN 0031-0182, E-ISSN 1872-616X, Vol. 429, p. 72-82Article in journal (Refereed)
    Abstract [en]

    The effects on calcite dissolution of both oceanic circulation and volcanic ash-fall were evaluated in lower bathyal sediments over the last 550 ka record from core MD 97-2114, recovered on the northern slope (depth of 1936 m, in the Pacific Deep Water, PDW) of the Chatham Rise (east of New Zealand, SW Pacific Ocean). This area has been impacted by changes in glacial/interglacial circulation and ocean chemistry as well as by the explosive volcanic activity of the Taupo Volcanic Zone. Several micro-paleontological dissolution proxies, based on planktonic foraminifera and calcareous nannofossils, were analysed in order to evaluate the calcite dissolution of the deep-sea sediments. These were compared with a couple of proxies of primary productivity (benthic foraminiferal epifaunal/infaunal ratio and delta C-13(benthic) (foraminifera)) and the abundance of volcanic glass. The dissolution proxy data from MD 97-2114 were compared with two nearby ODP sites, ODP 1123 (3290 m deep, bathed by the lower Circumpolar Deep Water, LCDW) and ODP 1125 (1365 m deep, bathed by the Antarctic Intermediate Water, AAIW). The results suggest: (1) the calcite dissolution/preservation cycles at all three core sites show Glacial-Interglacial (G-I) periodicities that match the previously described "Pacific-style" CaCO3 cycles; (2) several short-term dissolution events do not follow this general scheme and occur following tephra deposition. The dissolution related to the tephra deposition seems to have mostly affected calcareous nannofossils, thus we hypothesise that the ash-fall induced a temporary reduction of the surface water pH (below 7.8), which affected the coccolithophores that inhabit the surface waters. (3) Other short-term dissolution events (1000 years) are unrelated to tephra deposition and are possibly driven by the slowing of deep-sea circulation and a reduced Deep Western Boundary Current (DWBC). This lead to the dominance of older, more corrosive Pacific Deep Water (POW) flowing in to the region, resulting in coeval dissolution episodes at all three core sites (depth range from 1365 to 3290 m).

  • 7.
    Dupret, Vincent
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Organismal Biology, Evolution and Developmental Biology.
    Carls, Peter
    Martinez-Perez, Carlos
    Botella, Hector
    First Perigondwanan record of actinolepids (Vertebrata: Placodermi: Arthrodira) from the Lochkovian (Early Devonian) of Spain and its palaeobiogeographic significance2011In: Palaeogeography, Palaeoclimatology, Palaeoecology, ISSN 0031-0182, E-ISSN 1872-616X, Vol. 310, no 3-4, p. 273-282Article in journal (Refereed)
    Abstract [en]

    Different palaeogeographic models have been proposed for the position of Laurussia ( including Baltica) and Gondwana-derived microcontinents ( including Ibero-Armorica) during Ordovician to Late Carboniferous times. Principal differences concern the presence and duration of a large ocean, the Rheic Ocean, acting as a faunal barrier between these areas. The timing of the collision of Laurussia with Gondwana and/or Gondwana-derived terranes continues to be debated. Here we present new faunal data revealing close biogeographical relations between Ibero-Armorica ("Perigondwanan" or Gondwanan derivate terranes) and Podolia (SE margin of Baltica, in Laurussia). The placoderm assemblage found in the mid-late Lochkovian (Lower Devonian) of Celtiberia (north-central Spain), consisting of the 'actinolepid' species Kujdanowiaspis podolica, Erikaspis zychi and the acanthothoracid Palaeacanthaspis aff. P. vasta, is similar, both in terms of taxonomy and stratigraphic record, to that encountered in the Lochkovian of Podolia (Ukraine; Laurussia) and until now considered as endemic to this region. Moreover, vertebrate faunal links between Podolia and Celtiberia are also extended to the chondrichthyan scale-based species Seretolepis elegans and Altholepis composita previously documented exclusively from Laurussian localities (Podolia and Mackenzie Mountains in Canada), which occur together with the placoderm remains described herein. These evidences support the hypothesis that intermittent shallow neritic migration paths between Podolia (as well as "Avalonia") and Iberia existed in the late Lochkovian, agreeing with a palaeogeographic reconstruction showing close proximity between peri-Gondwanan or Gondwana-derived terranes and Laurussia. It supports the palaeogeographic model of the non-oceanic Variscan Mobile Crustal Field and it corroborates the arguments against wide oceans, acting as biogeographical relevant barriers, between Baltica and Gondwana in early Devonian times. The distribution patterns of heavy-shelled ostracods, turbidicolous brachiopods, and Rhenish trilobites also support these conclusions.

  • 8.
    Ebbestad, Jan Ove R.
    Uppsala University, Music and Museums, Museum of Evolution.
    Gastropoda, Tergomya and Paragastropoda (Mollusca) from the Lower Ordovician Fezouata Formation, Morocco2016In: Palaeogeography, Palaeoclimatology, Palaeoecology, ISSN 0031-0182, E-ISSN 1872-616X, Vol. 460, p. 87-96Article in journal (Refereed)
    Abstract [en]

    Gastropoda, Tergomya, and Paragastropoda (GTP) are a small but recognizable part of the collective Fezouata biota from the Lower Ordovician (Tremadocian-Floian) Fezouata Formation in Morocco. GTP range through the sequence but become more abundant and diverse in the stratigraphically higher and shallower marine parts of the succession. About 200 rock samples in existing collections have GTP but usually each slab contains several specimens so the number of individual is many times higher. A total of seven species are recognized of which four were known earlier. Gastropods are represented by the planispiral bellerophontoid Sinuites sp., recognized for the first time in the Tremadocian part of the succession, and the anisostrophic, nearly planispiral Lesueurilla prima (Barrande in Perner). Tergomyans are most abundant, dominated by the genus Carcassonnella with Carcassonnella courtessolei Horny and Peel, Carcassonnella vizcainoi Horny and Peel, and Carcassonnella sp. The latter encompass several specimens from different localities and stratigraphical levels, and may represent one of the named species or new varieties. Carcassonnella is for the first time recorded in the Tremadocian part of the succession. A second tergomyan is Thoralispira laevis (Thoral), while paragastropoda are represented byPelecyogyra fezouataensis Ebbestad and Lefebvre. In the peri-Gondwana area Carcassonnella, Thoralispira, and Lesueurilla are considered signature taxa, and the Fezouata GTP compare closely with those of Montagne Noire, France, both in composition and distribution. The Bohemian fauna is slightly younger (Floian-Darriwilian) with different species, except for Lesueurilla prima. The latter may have a wider distribution, being tentatively recognized in the Lower Ordovician of Argentina and Spain.

  • 9.
    Ekblom, Anneli
    et al.
    Uppsala University, Disciplinary Domain of Humanities and Social Sciences, Faculty of Arts, Department of Archaeology and Ancient History, African and Comparative Archaeology.
    Gillson, Lindsey
    University of Cape Town, South Africa.
    Dung fungi as indicators of past herbivore abundance, Kruger and Limpopo National Park2010In: Palaeogeography, Palaeoclimatology, Palaeoecology, ISSN 0031-0182, E-ISSN 1872-616X, Vol. 296, no 1-2, p. 14-27Article in journal (Refereed)
    Abstract [en]

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

  • 10.
    Ekblom, Anneli
    et al.
    Uppsala University, Disciplinary Domain of Humanities and Social Sciences, Faculty of Arts, Department of Archaeology and Ancient History, African and Comparative Archaeology.
    Gillson, Lindsey
    Plant Conservation Unit, Botany department, University of Cape Town.
    Risberg, Jan
    Bert Bolin Centre for Climate research, Stockholm University.
    Holmgren, Karin
    Bert Bolin Centre for Climate research, Stockholm University.
    Chidoub, Zara
    Rainfall variability and vegetation dynamics of the lower Limpopo Valley, Southern Africa, 500 AD to present2012In: Palaeogeography, Palaeoclimatology, Palaeoecology, ISSN 0031-0182, E-ISSN 1872-616X, Vol. 363, p. 69-78Article in journal (Refereed)
    Abstract [en]

    The long‐term responses of vegetation to climate variability are of relevance for predicting present and future vegetation change, and have implications for the management of savanna and riparian ecosystems. This paper explores the links between regional rainfall, hydrology and vegetation dynamics in the savannas and riverine forests of the lower Limpopo Valley, southern Africa, from 800 AD to the present, reviewing palaeoecological data (fossil pollen, spores, diatoms and lithology) from several hydrological systems in Kruger National Park (KNP), South Africa and Limpopo National Park (PNL), Mozambique. The PNL–KNP records show that riverine arboreal taxa expanded during wetter periods, including 800–1400 AD and after 1800 AD. Between 1400 and 1800 AD, grasses, savanna taxa and generalist taxa were favored over riparian taxa, a change that is linked with the onset of dry spells in the region (corresponding to the so-called Little Ice Age). The most extreme drought events around 1700 AD resulted in a marked decline of riparian forest taxa near Lake Mapimbi, KNP. In contrast, many water-scarce sequences away from the riverine environment, such as Radio Pan, Mafayeni Pan, Malahlapanga Pan and Lake Makwadzi show stable grassland vegetation throughout the last 1200 years. The results demonstrate the resilience of the grassland–savanna ecosystems to projected climate change with warmer and overall drier climate. The riverine forests are predicted to be more vulnerable especially as more extreme weather events are projected.

  • 11. Fox-Dobbs, Kena
    et al.
    Leonard, Jennifer A.
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Evolution, Genomics and Systematics, Evolutionary Biology.
    Koch, Paul L.
    Pleistocene megafauna from eastern Beringia: paleoecological and paleoenvironmental interpretations of stable carbon and nitrogen isotope and radiocarbon records2008In: Palaeogeography, Palaeoclimatology, Palaeoecology, ISSN 0031-0182, E-ISSN 1872-616X, Vol. 261, no 1-2, p. 30-46Article in journal (Refereed)
    Abstract [en]

    Late Pleistocene eastern Beringia is a model paleo-ecosystem for the study of potential and realized species interactions within a diverse mammalian fauna. Beringian paleontological records store a wealth of information that can be used to investigate how predator-prey and competitive interactions among consumers shifted in response to past episodes of environmental change. Two such recent periods of rapid climate change are the Last Glacial Maximum (LGM) and the end of glacial conditions at the beginning of the Holocene. Here we assemble carbon and nitrogen stable isotope, and AMS C-14 data collected from bone collagen of late Pleistocene carnivores and megafaunal prey species from the interior of eastern Beringia (Alaska), and reconstruct the diets of ancient Alaskan carnivores and herbivores. We are able to account for the relative influences of diet versus changing environmental conditions on variances in consumer isotope values, to identify species hiatuses in the fossil record, and to draw conclusions about paleoenvironmental conditions from faunal chronologies. Our isotopic results suggest that there was dietary niche overlap among some Beringian herbivore species, and partitioning among other species. We rely upon delta C-13 and delta N-15 values of modem Alaskan C-3 plant types to infer Beringian herbivore dietary niches. Horse, bison, yak, and mammoth primarily consumed grasses, sedges, and herbaceous plant species. Caribou and woodland muskox focused upon tundra plants, including lichen, fungi, and mosses. The network of Beringian carnivore interaction was complex and dynamic, some species (wolves) persisted for long periods of time, while others were only present during specific timeframes (large felids and ursids). Beringian carnivore diets included all measured herbivore species, although mammoth and muskox only appeared in carnivore diets during specific times in the late Pleistocene. We identified the potential presence of unmeasured diet sources that may have included forest-dwelling cervids and/or plant materials. None of the large-bodied carnivore species we analyzed (except short-faced bear) were specialized predators of a single prey species during the late Pleistocene. Differences in carnivore diet and dietary breadth between time periods either reflect changes in the relative abundances of prey on the Beringian landscape, or changes in competitive interactions among Beringian carnivore species

  • 12.
    Frisk, Åsa M.
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, Palaeobiology.
    Harper, David A.T.
    Late Ordovician brachiopod distribution and ecospace partitioning in the Tvären crater system, Sweden2013In: Palaeogeography, Palaeoclimatology, Palaeoecology, ISSN 0031-0182, E-ISSN 1872-616X, Vol. 369, p. 114-124Article in journal (Refereed)
    Abstract [en]

    Patterns of distribution and ecospace utilization of Late Ordovician brachiopods in a recently formed, contemporary meteorite crater are described and analyzed. Rhynchonelliformean brachiopod communities, dominated by a wide range of orthides and strophomenides, colonized the newly formed crater. At the crater rim communities were established early on, although the crater depression was not inhabited until deposition of the upper third of the remaining crater fill. The crater formed a protected but restricted microenvironment where sediments four times the thickness of the nearby basinal succession accumulated. Within this narrow space environments varied from shallow-water to deeper-waters, about 200 m in depth, and from well oxygenated to hypoxic. Such varied environments generated a rough ecological landscape, facilitating niche partitioning across a relatively small geographic area. Analysis of the guild structure of the fauna permits explanation of a local biodiversity hotspot in otherwise low-diversity strata elsewhere in the Scandinavian region. The Tvären impact event had an important palaeobiologic effect upon the fossil record as it served as a local pump and reservoir for biodiversity. Moreover the development of new community types and narrowly-defined niches helped further drive both α and β biodiversity during a critical phase of the Great Ordovician Biodiversification Event.

  • 13. Haig, David W.
    et al.
    Martin, Sarah K.
    Mory, Arthur J.
    McLoughlin, Stephen
    Backhouse, John
    Berrell, Rodney W.
    Kear, Benjamin P.
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, Palaeobiology.
    Hall, Russell
    Foster, Clinton B.
    Shi, Guang R.
    Bevan, Jennifer C.
    Early Triassic (early Olenekian) life in the interior of East Gondwana: mixed marine-terrestrial biota from the Kockatea Shale, Western Australia2015In: Palaeogeography, Palaeoclimatology, Palaeoecology, ISSN 0031-0182, E-ISSN 1872-616X, Vol. 417, p. 511-533Article in journal (Refereed)
    Abstract [en]

    A new terrestrial marine assemblage from the lower beds of a thin outcrop section of the Kockatea Shale in the northern Perth Basin, Western Australia, contains a range of fossil groups, most of which are rare or poorly known from the Lower Triassic of the region. To date, the collection includes spinose acritarchs, organic-cemented agglutinated foraminifera, lingulids, minute bivalves and gastropods, ammonoids, spinicaudatans, insects, austriocaridid crustaceans, actinopterygians, a temnospondyl-like mandible, plant remains, and spores and pollen. Of these groups, the insects, crustaceans and macroplant remains are recorded for the first time from this unit. Palynomorphs permit correlation to nearby sections where conodonts indicate an early Olenekian (Smithian) age. The locality likely represents the margin of an Early Triassic shallow interior sea with variable estuarine-like water conditions, at the southwestern end of an elongate embayment within the East Gondwana interior rift sag system preserved along the Western Australian margin. Monospecific spinose acritarch assemblages intertwined with amorphous organic matter may represent phytoplankton blooms that accumulated as mats, and suggest potentially eutrophic surface waters. The assemblage represents a mixure of marine and terrestrial taxa, suggesting variations in water conditions or that fresh/brackish-water and terrestrial organisms were transported from adjacent biotopes. Some of the lower dark shaly beds are dominated by spinicaudatans, likely indicating periods when the depositional water body was ephemeral, isolated, or subjected to other difficult environmental conditions. The biota of the Kockatea Shale is insufficiently known to estimate biotic diversity and relationships of individual taxa to their Permian progenitors and Triassic successors, but provides a glimpse into a coastal-zone from the interior of eastern Gondwana. Specialist collecting is needed to clarify the taxonomy of many groups, and comparisons to other Lower Triassic sites are required to provide insights into the pattern of biotic decline and recovery at the end-Permian crisis. (C) 2014 Elsevier B.V. All rights reserved.

  • 14.
    Han, Zhiyong
    et al.
    Nanjing Univ, Sch Geog & Oceanog Sci, Nanjing 210023, Jiangsu, Peoples R China..
    Li, Xusheng
    Nanjing Univ, Sch Geog & Oceanog Sci, Nanjing 210023, Jiangsu, Peoples R China..
    Yi, Shuangwen
    Nanjing Univ, Sch Geog & Oceanog Sci, Nanjing 210023, Jiangsu, Peoples R China..
    Stevens, Thomas
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, LUVAL.
    Chen, Yingyong
    Nanjing Univ, Sch Geog & Oceanog Sci, Nanjing 210023, Jiangsu, Peoples R China..
    Wang, Xiaoyong
    Nanjing Univ, Sch Geog & Oceanog Sci, Nanjing 210023, Jiangsu, Peoples R China..
    Lu, Huayu
    Nanjing Univ, Sch Geog & Oceanog Sci, Nanjing 210023, Jiangsu, Peoples R China..
    Extreme monsoon aridity episodes recorded in South China during Heinrich Events2015In: Palaeogeography, Palaeoclimatology, Palaeoecology, ISSN 0031-0182, E-ISSN 1872-616X, Vol. 440, p. 467-474Article in journal (Refereed)
    Abstract [en]

    Geological records of climate change since the last glaciation in South China, a core area of the East Asian monsoon, are key to understanding secular variation in the monsoon system. However, with the exception of the speleothems, records from this area with independent age control are few. We investigated aeolian sand deposition on a sand hill on the shore of Poyang Lake in South China and reconstructed the chronological sequence of aeolian deposition using Optically Stimulated Luminescence (OSL) dating. Without exception, all aeolian sediments were deposited within seven periods that generally match the timing of Heinrich events and other cold periods in Greenland. We argue that aeolian sand accumulation in this region is most likely forced by extreme aridity driven by weakening of the summer monsoon, while the characteristics of this deposition are influenced by winter monsoon intensity. The monsoon shifts revealed here suggest a possible link between North Atlantic cooling and summer monsoon strength in South China, and support the intensities of cooling phases recorded in Greenland ice cores.

  • 15.
    Jarochowska, Emilia
    et al.
    GeoZentrum Nordbayern, Fachgruppe Paläoumwelt, University of Erlangen-Nuremberg, Loewenichstr. 28, 91054 Erlangen, Germany.
    Bremer, Oskar
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Organismal Biology, Evolution and Developmental Biology.
    Heidlas, Daniel
    GeoZentrum Nordbayern, Fachgruppe Paläoumwelt, University of Erlangen-Nuremberg, Loewenichstr. 28, 91054 Erlangen, Germany.
    Pröpster, Stephanie
    GeoZentrum Nordbayern, Fachgruppe Paläoumwelt, University of Erlangen-Nuremberg, Loewenichstr. 28, 91054 Erlangen, Germany.
    Vandenbroucke, Thijs R.A.
    Department of Geology, Ghent University, Krijgslaan 281-S8, B-9000 Ghent, Belgium;Evo-Eco-Paléo UMR 8198, Université de Lille, Avenue Paul Langevin, Bâtiment SN5, 59655 Villeneuve d'Ascq Cedex, France.
    Munnecke, Axel
    GeoZentrum Nordbayern, Fachgruppe Paläoumwelt, University of Erlangen-Nuremberg, Loewenichstr. 28, 91054 Erlangen, Germany.
    End-Wenlock terminal Mulde carbon isotope excursion in Gotland, Sweden: Integration of stratigraphy and taphonomy for correlations across restricted facies and specialized faunas2016In: Palaeogeography, Palaeoclimatology, Palaeoecology, ISSN 0031-0182, E-ISSN 1872-616X, Vol. 457, p. 304-322Article in journal (Refereed)
  • 16.
    Kars, Myriam
    et al.
    Kochi Univ, Ctr Adv Marine Core Res, B200 Monobe, Nankoku, Kochi 7830004, Japan..
    Musgrave, Robert J.
    Univ Sydney, Sch Geosci, Sydney, NSW 2006, Australia.;Geol Survey New South Wales, NSW Dept Ind, Maitland, NSW 2320, Australia..
    Kodama, Kazuto
    Kochi Univ, Ctr Adv Marine Core Res, B200 Monobe, Nankoku, Kochi 7830004, Japan..
    Jonas, Ann-Sophie
    Christian Albrethts Univ, Inst Geosci, Dept Organ Geochem, Ludewig Meyn Str 10, D-24118 Kiel, Germany..
    Bordiga, Manuela
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences.
    Ruebsam, Wolfgang
    Christian Albrethts Univ, Inst Geosci, Dept Organ Geochem, Ludewig Meyn Str 10, D-24118 Kiel, Germany..
    Mleneck-Vautravers, Maryline J.
    Univ Cambridge, Dept Earth Sci, Downing St, Cambridge CB2 3EQ, England..
    Bauersachs, Thorsten
    Christian Albrethts Univ, Inst Geosci, Dept Organ Geochem, Ludewig Meyn Str 10, D-24118 Kiel, Germany..
    Impact of climate change on the magnetic mineral assemblage in marine sediments from Izu rear arc, NW Pacific Ocean, over the last 1 Myr2017In: Palaeogeography, Palaeoclimatology, Palaeoecology, ISSN 0031-0182, E-ISSN 1872-616X, Vol. 480, p. 53-69Article in journal (Refereed)
    Abstract [en]

    A rock magnetic study was conducted on upper Pleistocene marine sediments from International Ocean Discovery Program Expedition 350 Site U1437 in order to highlight the paleoenvironmental changes in the NW Pacific Ocean influenced by the East Asian monsoon regime. Remanent magnetization analyses, hysteresis properties, first-order reversal curves and low temperature magnetic measurements were carried out, along with electron microscope observations. The results indicate that coarse-grained (titano)-magnetite is the dominant magnetic phase in the magnetic mineral assemblage. Time-series analysis supports that this assemblage is modulated by global climate changes over the last 1 Myr. During the interglacial stages, magnetic minerals are more abundant; and are dominated by coarse-grained (titano)-magnetite of both terrigenous (likely from mainland China) and volcanic (Izu arc front, Japan) origin. During the glacial stages, the magnetic mineral content is lower, probably reflecting partial dissolution of (Ti)-magnetite, and the magnetic assemblage is composed of terrigenous coarse-grained (titano)-magnetite and of higher coercivity, presumably finer eolian particles (likely hematite) as a result of the enhancement of the winter monsoon in continental Asia. The magnetic mineral assemblage reflects a superimposition of volcanic and global climate signals. Bulk organic-geochemical analyses for total and organic carbon as well as nitrogen and sulfur contents confirm a climatic signature in the composition of the sediments with more oxygenated water masses being present during glacial periods. Additional X-ray fluorescence measurements on bulk samples indicate various origins of the sediment particles with both proximal and distal sources.

  • 17.
    Looy, Cindy V.
    et al.
    Univ Calif Berkeley, Dept Integrat Biol, Berkeley, CA 94720 USA.;Univ Calif Berkeley, Museum Paleontol, Berkeley, CA 94720 USA..
    Ranks, Stephanie L.
    Univ Calif Berkeley, Dept Integrat Biol, Berkeley, CA 94720 USA.;Univ Calif Berkeley, Museum Paleontol, Berkeley, CA 94720 USA..
    Chaney, Dan S.
    Smithsonian Inst, NMNH, Dept Paleobiol, Washington, DC 20560 USA..
    Sanchez, Sophie
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Organismal Biology, Evolution and Developmental Biology.
    Steyer, Jean-Sebastien
    UPMC, Ctr Rech Paleobiodivers & Paleoenvironnements, MNHN, UMR 7207,CNRS, CP 38,8 Rue Buffon, F-75005 Paris, France..
    Smith, Roger M. H.
    Iziko South African Museum, Karoo Palaeontol, ZA-8000 Cape Town, South Africa.;Univ Witwatersrand, Evolutionary Studies Inst, 1 Jan Smuts Ave, ZA-2000 Johannesburg, South Africa..
    Sidor, Christian A.
    Univ Washington, Burke Museum, Seattle, WA 98195 USA.;Univ Washington, Dept Biol, Seattle, WA 98195 USA..
    Myers, Timothy S.
    So Methodist Univ, Huffington Dept Earth Sci, Dallas, TX 75275 USA..
    Ide, Oumarou
    Inst Rech Sci Humaines, Niamey, Niger..
    Tabor, Neil J.
    So Methodist Univ, Huffington Dept Earth Sci, Dallas, TX 75275 USA..
    Biological and physical evidence for extreme seasonality in central Permian Pangea2016In: Palaeogeography, Palaeoclimatology, Palaeoecology, ISSN 0031-0182, E-ISSN 1872-616X, Vol. 451, p. 210-226Article in journal (Refereed)
    Abstract [en]

    Climate models indicate increased desertification in the continental interior of Pangea during the Permian, which would have affected the composition of the flora and fauna. We present a multi-proxy paleoenvironmental reconstruction of a terrestrial ecosystem in central Pangea of Lopingian age. The reconstruction is based on biological and physical data from the Moradi Formation, located in the Tim Mersoi sub-Basin, northern Niger. Paleosols and sedimentological evidence indicate that the prevailing climate was semi-arid to very arid with marked intervals of high water availability. Carbon stable isotope data from organic matter and paleosols suggest that both the soil productivity and actual evapotranspiration were very low, corresponding to arid conditions. Histological analysis of pareiasaur bones shows evidence of active metabolism and reveals distinct growth marks. These interruptions of bone formation are indicative of growth rhythms, and are considered as markers for contrasting seasonality orepisodic climate events. The macrofossil floras have low diversity and represent gymnosperm dominated woodlands. Most notable are ovuliferous dwarf shoots of voltzian conifers, and a 25-m long tree trunk with irregularly positioned branch scars. The combined biological and physical evidence suggests that the Moradi Formation was deposited under a generally arid climate with recurring periods of water abundance, allowing for a well-established ground water-dependent ecosystem. With respect to its environment, this system is comparable with modern ecosystems such as the southern African Namib Desert and the Lake Eyre Basin in Australia, which are discussed as modern analogues.

  • 18. Narkiewicz, Marek
    et al.
    Grabowski, Jacek
    Narkiewicz, Katarzyna
    Niedzwiedzki, Grzegorz
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Organismal Biology, Evolution and Developmental Biology.
    Retallack, Gregory J.
    Szrek, Piotr
    De Vleeschouwer, David
    Palaeoenvironments of the Eifelian dolomites with earliest tetrapod trackways (Holy Cross Mountains, Poland)2015In: Palaeogeography, Palaeoclimatology, Palaeoecology, ISSN 0031-0182, E-ISSN 1872-616X, Vol. 420, p. 173-192Article in journal (Refereed)
    Abstract [en]

    The Eifelian dolomites in the Zachelmie Quarry (Holy Cross Mountains, Poland) contain tracicways and tracks of tetrapods 390-391 Ma old, and thus the oldest known so far. The environments of the trackway-bearing beds have been investigated using sedimentological, palaeontological, geochemical and palaeomagnetic methods. The reconstructed tetrapod habitats comprised shallow-water lagoons separated from an open marine basin by sparsely vegetated islands and spits. The lagoonal waters were well-aerated and a few metres deep at most, undergoing periodic desiccation. The dolomitic sediments, primarily of microbial origin, formed in tropical waters of slightly modified marine composition. Oxygen isotope data obtained from the dolomicrites suggest water temperatures around 30 degrees C. The seasonal semi-arid to sub-humid climate, deduced from paleosol characteristics, was probably of a tropical monsoonal type. The degree of restriction of the lagoonal system evolved from relatively open, evaporation-dominated towards increasingly closed, freshwater influenced. The detailed observations of the footprint-bearing beds, as well as the characteristics of the tracks, indicate that they were formed mostly under subaqueous conditions, by wading, walking on the bottom or swimming animals. Lack of tidal indicators in the restricted Zachelmie lagoons argues against previous concept that tidal flats served as a food source for the early tetrapods. Nor is a hypothesis of flooded woodlands confirmed as a habitat promoting the "fish-to-tetrapod" transition. We propose that functional limbs emerged among aqueous animals that acquired their locomotional capabilities in a shallow lagoonal water before attempting longer excursions on land.

  • 19. Nie, Junsheng
    et al.
    Peng, Wenbin
    Pfaff, Katharina
    Moeller, Andreas
    Garzanti, Eduardo
    Ando, Sergio
    Stevens, Thomas
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, LUVAL.
    Bird, Anna
    Chang, Hong
    Song, Yougui
    Liu, Shanpin
    Ji, Shunchuan
    Controlling factors on heavy mineral assemblages in Chinese loess and Red Clay2013In: Palaeogeography, Palaeoclimatology, Palaeoecology, ISSN 0031-0182, E-ISSN 1872-616X, Vol. 381, p. 110-118Article in journal (Refereed)
  • 20.
    Niedzwiedzki, Grzegorz
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Organismal Biology, Evolution and Developmental Biology.
    Bajdek, Piotr
    Aleja Najswietszej Maryi Panny 20-20A, PL-42200 Czestochowa, Poland..
    Owocki, Krzysztof
    Polish Acad Sci, Inst Paleobiol, Twarda 51-55, PL-00818 Warsaw, Poland..
    Kear, Benjamin P.
    Uppsala University, Music and Museums, Museum of Evolution.
    An Early Triassic polar predator ecosystem revealed by vertebrate coprolites from the Bulgo Sandstone (Sydney Basin) of southeastern Australia2016In: Palaeogeography, Palaeoclimatology, Palaeoecology, ISSN 0031-0182, E-ISSN 1872-616X, Vol. 464, p. 5-15Article in journal (Refereed)
    Abstract [en]

    Vertebrate trace fossils often provide a measure of cryptic biodiversity, and are especially pertinent when skeletal remnants are exceptionally rare. The Lower Triassic (lower Olenekian) Bulgo Sandstone at Long Reef in the Sydney Basin of southeastern Australia constitutes just such a deposit, having yielded isolated bones of giant capitosaurian temnospondyls and proterosuchid archosauriforms, together with abundant coprolites that are geochemically rich in elemental phosphate and carbon denoting vertebrate predators. Microstructural analysis of these preserved droppings reveals occasional bone fragments, fish scales, insect cuticles, plant material and bacterial traces (pseudomorph voids), as well as silicate mineral particles. REE concentrations indicate that burial and early diagenesis occurred explicitly within fluvial sediments. Furthermore, external morphological characterization permits attribution of spiral coprolites to chondrichthyan or osteichthyan fishes, polygonal, ovoid spherical and typically flattened feces to temnospondyls, and conspicuously large cylindrical droppings to archosauriforms or other amniote apex predators. Collectively, the Bulgo Sandstone coprolite assemblage thus offers new insights into ecosystem structure and palaeoenvironment in what was an earliest Triassic near polar setting. Such data compliments the documented skeletal record, but indicates a greater range of aquatic and possibly terrestrial carnivores the latter being enigmatically sparse in the Australian Triassic and yet detected here via the hitherto underexplored trace fossil evidence of their ecological presence.

  • 21.
    Niedzwiedzki, Grzegorz
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Organismal Biology, Evolution and Developmental Biology.
    Bajdek, Piotr
    Aleja Najswietszej Maryi Panny 20-20A, PL-42200 Czestochowa, Poland..
    Qvarnström, Martin
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Organismal Biology, Evolution and Developmental Biology.
    Sulej, Tomasz
    Polish Acad Sci, Inst Paleobiol, Twarda 51-55, PL-00818 Warsaw, Poland..
    Sennikov, Andrey G.
    Russian Acad Sci, Borissiak Paleontol Inst, Profsoyuznaya 123, Moscow 117997, Russia.;Kazan Fed Univ, Kremlyovskaya 18, Kazan 420008, Russia..
    Golubev, Valeriy K.
    Russian Acad Sci, Borissiak Paleontol Inst, Profsoyuznaya 123, Moscow 117997, Russia.;Kazan Fed Univ, Kremlyovskaya 18, Kazan 420008, Russia..
    Reduction of vertebrate coprolite diversity associated with the end-Permian extinction event in Vyazniki region, European Russia2016In: Palaeogeography, Palaeoclimatology, Palaeoecology, ISSN 0031-0182, E-ISSN 1872-616X, Vol. 450, p. 77-90Article in journal (Refereed)
    Abstract [en]

    This study investigates the paleoecological significance of vertebrate coprolites collected from seven sections and three lithofacies of the uppermost Permian and lowermost Triassic succession from the Vyazniki site in the European part of Russia. The analyzed specimens (coprolites and possibly some cololites) were grouped into nine morphotypes (A-I). The coprolite morphotypes were characterized geochemically and compared to the record of other Permian and Triassic coprolites worldwide. Based on the stratigraphic position, shape, structure and composition, all morphotypes were linked to supposed producers. The phosphatic composition of most of the morphotypes and inclusions of arthropod remains, fish scales and bone fragments, suggest that they were produced by carnivores, but non-phosphatic, carbonate-rich, large and oval-shaped coprolites with impressions after plant remains have also been found. The extinction of terrestrial vertebrates around the Permian-Triassic boundary in Russia is interpreted to have occurred within a few thousands of years. Here, we show a pattern of coprolite morphotypes disappearing across this boundary that is consistent with a relatively sudden change in the vertebrate faunal composition across this interval.

  • 22.
    Petryshyn, Victoria
    et al.
    Department of Earth, Planetary, and Space Sciences, University of California, Los Angeles, Los Angeles, CA, USA.
    Juarez Rivera, Marisol
    School of Earth and Space Exploration, Arizona State University, Tempe, AZ, USA.
    Agić, Heda
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, Palaeobiology.
    Frantz, Carie
    Applied Physics Laboratory, University of Washington, Seattle, WA, USA.
    Corsetti, Frank
    Department of Earth Sciences, University of Southern California, Los Angeles, CA, USA.
    Tripati, Aradhna
    Department of Earth, Planetary, and Space Sciences, University of California, Los Angeles, Los Angeles, CA, USA.
    Stromatolites in Walker Lake (Nevada, Great Basin, USA) record climate and lake level changes ~ 35,000 years ago2016In: Palaeogeography, Palaeoclimatology, Palaeoecology, ISSN 0031-0182, E-ISSN 1872-616X, Vol. 451, p. 140-151Article in journal (Refereed)
    Abstract [en]

    Walker Lake is a closed-basin remnant of the large Pleistocene glacial Lake Lahontan system that has experienced multiple high amplitude (100–200 m) changes in water level over the past ~ 40,000 years in response to changes in climate. A laminated carbonate stromatolite composed of varying proportions of calcite fans and micrite was collected from a paleoshoreline located at approximately 58 m above present lake level. Radiocarbon dating revealed that the stromatolite spans approximately 2000 years of growth, from 35,227 to 33,727 calibrated years before present (YBP), a time period during which paleolake-level is not well-constrained. Distinct laminae were drilled along the growth axis, and the resulting powders were collected for clumped isotope analyses to generate formation temperatures (lake water temperatures) during stromatolite formation from which δ18Owater was calculated.

    Results indicate that the stromatolite experienced an initial increase in temperature and water δ18O values followed by a decrease in both during the course of accretion. The resulting temperature and isotopic data were input into a Rayleigh distillation model for lakewater evaporation in order to estimate the magnitude of lake level and volume fluctuations over the course of accretion. Modeling results reveal a lake level decrease of between 8.1 and 15.6 m, followed by an increase of between 4.3 and 8.8 m during the course of stromatolite growth.

    The results of this study indicate that Walker Lake experienced significant lake volume change over the course of 2000 years, perhaps as a response to precipitation changes driven by fluctuations in the polar jet stream and accompanying changes in regional climate, and/or evaporation-induced changes in lake level. These results add to a growing body of research indicating that stromatolites and other lacustrine tufas represent a detailed and extensive terrestrial archive that can potentially be used to reconstruct the timing and magnitude of climate change.

  • 23. Posenato, Renato
    et al.
    Holmer, Lars E.
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, Palaeobiology.
    Prinoth, Herwig
    Adaptive strategies and environmental significance of lingulid brachiopods across the late Permian extinction2014In: Palaeogeography, Palaeoclimatology, Palaeoecology, ISSN 0031-0182, E-ISSN 1872-616X, Vol. 399, p. 373-384Article in journal (Refereed)
    Abstract [en]

    Linguliform brachiopods are traditionally considered a conservative group which seems to pass through the late Permian extinction without any significant loss and even appear to thrive immediately after the extinction peak. In the Southern Alps, lingulids are very common in the post-extinction Mazzin Member (early Induan) of the Werfen Formation. Sparse occurrences are also known in the overlying Siusi and Gastropod Oolite members (late Induan and early Olenekian in age respectively). The recent discovery of well preserved specimens from a pre-extinction bed of the Bellerophon Formation (Changhsingian) has permitted a detailed comparative analysis, mostly based on the interior characters, preserved in the lingulid succession from across the extinction beds. The following effects on the lingulid populations have been analyzed: i) change in taxonomic assessment; ii) adaptive strategies during the surviving and recovery phases; and iii) environmental proxy connected with the killing mechanisms of the late Permian extinction.

    The pre-extinction individuals belong to Lingularia? cf. smirnovae Biernat and Emig, a species that is characterized by large-sized shells with a short lophophoral cavity. The post-extinction populations belong to different species and, probably, even to a different genus. The first post-extinction population (early Induan), with small-sized shells and long lophophoral cavity, has been referred to Lingularia yini (Peng and Shi). It records the most severe effects of the late Permian extinction on the marine ecosystems. The late Induan–Olenekian Lingularia borealis (Bittner), with large sized shells and long lophophoral cavity, appears during the first phase of the Triassic biotic recovery.

    The main adaptive strategies of Lingularia yini, in comparison with the Permian species, include: i) shell miniaturization; ii) increasing of the lophophoral cavity surface (respiratory surface); and iii) increasing of shell width/length ratio. These modifications are interpreted as adaptations towards warming and hypoxia, two main killing mechanisms of the marine biota. The recovery species Lingularia borealis maintains a large lophophoral cavity, indicating an adaptation towards predominant low oxygenated bottom marine waters.

    The appearance and the great abundance of Lingularia yini in the Mazzin Member (early Induan) represent a proxy of dysaerobic conditions, which determined the appearance of the second phase of the Lilliput biota, characterized by the definitive disappearance of the rhynchonelliform brachiopods and calcareous algae in the Southern Alps.

  • 24. Scholze, Frank
    et al.
    Golubev, Valeriy K.
    Niedzwiedzki, Grzegorz
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Organismal Biology, Evolution and Developmental Biology.
    Sennikov, Andrey G.
    Schneider, Joerg W.
    Silantiev, Vladimir V.
    Early Triassic Conchostracans (Crustacea: Branchiopoda) from the terrestrial Permian-Triassic boundary sections in the Moscow syncline2015In: Palaeogeography, Palaeoclimatology, Palaeoecology, ISSN 0031-0182, E-ISSN 1872-616X, Vol. 429, p. 22-40Article in journal (Refereed)
    Abstract [en]

    The Permian-Triassic boundary marks the greatest mass extinction in Earth's history. In order to understand the real causes of this severe extinction event, multidisciplinary investigations around the globe are required. Here, the terrestrial Permian-Triassic boundary sections in the Vladimir region, Central Russia, were sampled bed-by-bed for conchostracan study. In the Early Triassic intervals the following taxa were recognized for the first time: Cornia germari (Beyrich, 1857), Euestheria gutta (Lutkevitch, 1937), Magniestheria mangaliensis (Jones, 1862), Palaeolimnadiopsis vilujensis Varentsov, 1955, and Rossolimnadiopsis Novozhilov, 1958. The wide distribution of C germari demonstrates their high value for biostratigraphy, since this species was also reported from the Lower Buntsandstein Subgroup in the Germanic Basin as well as from Early Triassic deposits in Hungary, Greenland and Siberia. The assumption of an Early Triassic age of the studied sections is also supported by associated Tupilakosaurus bone fragments, which point to the Tupilakosaurus wedugensis Zone in the earliest Triassic.

  • 25.
    Skrzycki, Piotr
    et al.
    Polish Acad Sci, Inst Paleobiol, Twarda 51-55, PL-00818 Warsaw, Poland..
    Niedzwiedzki, Grzegorz
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Organismal Biology, Evolution and Developmental Biology.
    Talanda, Mateusz
    Univ Warsaw, Dept Palaeobiol & Evolut, Biol & Chem Res Ctr, Fac Biol, Zwirki & Wigury 101, PL-02089 Warsaw, Poland..
    Dipnoan remains from the Lower-Middle Triassic of the Holy Cross Mountains and northeastern Poland, with remarks on dipnoan palaeobiogeography2018In: Palaeogeography, Palaeoclimatology, Palaeoecology, ISSN 0031-0182, E-ISSN 1872-616X, Vol. 496, p. 332-345Article in journal (Refereed)
    Abstract [en]

    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 degrees.

  • 26. Slater, Ben
    et al.
    McLoughlin, Stephen
    Hilton, Jason
    Animal–plant interactions in a Middle Permian permineralised peat of the Bainmedart Coal Measures, Prince Charles Mountains, Antarctica2012In: Palaeogeography, Palaeoclimatology, Palaeoecology, ISSN 0031-0182, E-ISSN 1872-616X, Vol. 363, p. 109-126Article in journal (Refereed)
    Abstract [en]

    Evidence for invertebrate feeding on glossopterid gymnosperms is documented from Middle Permian silicified peats of the Prince Charles Mountains, Antarctica, in the form of coprolites occurring both free in the peat matrix and clustered within excavations in roots, aerial wood and leaves. Observations of coprolites in thin-sections of the peats and from scanning electron microscopy of examples extracted via bulk maceration reveal nine morphotypes distinguished by size, shape, surface texture and contents. These include coprolites with coarse plant debris, spirally ornamented coprolites, coprolites containing spore/pollen remains and fern sporangia, coprolites within Glossopteris leaves, an ellipsoidal morphotype within a fern sporangium, large isolated coprolites between matted leaves, clustered forms filling galleries inside Vertebraria roots and Australoxylon wood, forms with coarse indeterminate constituents and others with fungal contents. Other faunal evidence is limited to indeterminate arthropod exoskeleton fragments. Collectively, the coprolites within the permineralised peat from the Prince Charles Mountains document the presence of diverse feeding behaviours including stem feeding, sporangial feeding, palynivory, root feeding and mycophagy. The first evidence of invertebrate feeding traces in Vertebraria (glossopterid) roots is identified. These findings indicate that herbivory by invertebrates in the high-latitude Permian forest-mire ecosystems of Antarctica was more intense and diverse than previous studies have reported, and affected all parts of the Glossopteris plant, together with components of associated herbaceous taxa.

  • 27.
    Szrek, Piotr
    et al.
    Polish Geol Inst, Natl Res Inst, Rakowiecka 4 St, PL-00075 Warsaw, Poland. Polish Geol Inst, Natl Res Inst, Holy Cross Mt Branch, Zgoda 21 St, PL-00075 Kielce, Poland..
    Salwa, Sylwester
    Holy Cross Mountains Branch of the Polish Geological Institute—National Research Institute, Zgoda 21 Street, 00-075 Kielce, Poland.
    Niedzwiedzki, Grzegorz
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Organismal Biology, Evolution and Developmental Biology.
    Dec, Marek
    Polish Acad Sci, Inst Paleobiol, Twarda 51-55, PL-00818 Warsaw, Poland..
    Ahlberg, Per E.
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Organismal Biology, Evolution and Developmental Biology.
    Uchman, Alfred
    Jagiellonian Univ, Inst Geol Sci, Oleandry 2a, PL-30063 Krakow, Poland..
    A glimpse of a fish face: An exceptional fish feeding trace fossil from the Lower Devonian of the Holy Cross Mountains, Poland2016In: Palaeogeography, Palaeoclimatology, Palaeoecology, ISSN 0031-0182, E-ISSN 1872-616X, Vol. 454, p. 113-124Article in journal (Refereed)
    Abstract [en]

    An exceptionally well-preserved assemblage of numerous invertebrate and vertebrate trace fossils is described from the Lower Devonian of the Holy Cross Mountains, southern Poland. Two trace-bearing horizons occur in the shallow-marine sequence that is exposed in a small outcrop near Ujazd village. One of the trace fossils is preserved as a bilobate, generally elliptical, epichnial pit is described as Osculichnus tarnowskae isp. nov. and interpreted as a unique example of praedichnia. Neoichnologic experiments and observations indicate that the ichnogenus Osculichnus was produced by feeding fish. The fish producing O. tarnowskae probably hunted bivalves, polychaetes and arthropods, which are represented by invertebrate trace fossils in the same horizons. The overall shape and morphological details of O. tarnowskae suggest that it was made by a lungfish broadly similar to Dipnorhynchus. The trace provides the first direct evidence for Devonian lungfish feeding behaviour, as well as the first record of three-dimensional soft-tissue morphology of the snout area of an Emsian representative of this group. The trace fossils from Ujazd provide new insight into the palaeoecology and taphonomy of the Lower Devonian of the Holy Cross Mountains.

  • 28. Waloszek, Dieter
    et al.
    Maas, Andreas
    Chen, Junyuan
    Stein, Martin
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, Palaeobiology.
    Evolution of cephalic feeding structures and the phylogeny of Arthropoda2007In: Palaeogeography, Palaeoclimatology, Palaeoecology, ISSN 0031-0182, E-ISSN 1872-616X, Vol. 254, no 1-2, p. 273-287Article in journal (Refereed)
    Abstract [en]

    Focusing on structural and functional changes during the evolution of Arthropoda, we based our approach on evidence provided by two major Cambrian lagerstätten yielding exceptional preservation: the Lower Cambrian Chengjiang lagerstätte, Yunnan Province, China, and the Lower to Upper Cambrian ‘Orsten’-type lagerstätten with their 3D-preserved fossils. We established a model of major steps in the evolution of the arthropod feeding system, with emphasis on the head region. Using fossils, we identify two major gaps in our knowledge about this evolutionary process to be filled in the future. One of them is how development progressed from the stem arthropod level toward that of Arthropoda s. str. The latter stage is known now from three Chengjiang taxa, which possess, besides other features, a head composed of only two segments, i.e. those bearing the compound eyes and the limb-shaped antennulae. The post-antennular trunk limbs are very simple and lack any feeding structures, spines or setae. With this, only the antennula could have been involved in food gathering. Another uncertainty concerns the transition from the Arthropoda s. str. level to that of the Euarthropoda. Euarthropoda embraces all those well-sclerotized arthropods with extant descendants, and its ground pattern includes a larger head tagma with four appendage-bearing segments and post-antennular limbs made of a rigid, but flat gnathobasic basipod carrying two rami. At this stage, feeding had become more elaborate than before, yet all post-antennular appendages remained serially designed. Crustacea changed their feeding system initially by modifying the anterior three cephalic appendages, and the mouth area and by developing a specific setation on various body parts. Subsequently, more appendages became involved within certain in-group taxa. Our model elucidates that changes of the functional system occurred at the macroscopic and the microscopic level. Although many allied features, such as the gut system or the appendage morphology, remained remarkably conservative over longer periods, feeding was most likely a significant driving force for evolutionary changes in the morphology of arthropods, particularly of the head region.

  • 29.
    Wang, Haizhou
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, Palaeobiology.
    Zhang, Zhifei
    Holmer, Lars E.
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, Palaeobiology.
    Holmer, E.
    Hu, Shixue
    Wang, Xiangren
    Li, Guoxiang
    Peduncular attached secondary tiering acrotretoid brachiopods from the Chengjiang fauna: Implications for the ecological expansion of brachiopods during the Cambrian explosion2012In: Palaeogeography, Palaeoclimatology, Palaeoecology, ISSN 0031-0182, E-ISSN 1872-616X, Vol. 323-325, p. 60-67Article in journal (Refereed)
    Abstract [en]

    Brachiopods are usually thought to contribute little to the tiering complexity from the Paleozoic to the Recent, mainly due to the fact that their recent representatives live primarily in lower tiers directly above or below the water-sediment interface. Here we present the first and oldest record of varied levels of secondary tiering in minute brachiopods attached by exceptionally preserved thread-like pedicles around the branched fronds of the algae-like Malongitubus kuangshanensis Hu, 2005. The specimens illustrated herein were recovered from the Chengjiang fauna (Series 2, Stage 3) in the Lower Cambrian Heilinpu Formation at the Kuangshan section in Malong County, Yunnan Province, southern China. The micro-morphology and oval outline of the attached brachiopods demonstrate that they can be assigned to acrotretoid brachiopods (Linguliformea, Lingulata, Acrotretoidea), described here as Kuangshanotreta malungensis gen. et sp. nov. This is the first report on the occurrence of acrotretoid brachiopods in the Lower Cambrian muddy deposits from southern China. The posterior margins of the Kuangshanotreta shells are invariably either in direct contact with, or directed towards, and then in situ attached to the algal frond of M. kuangshanensis, indicating a secondary tiering in the ecological structure of Early Cambrian brachiopods. The acrotretoid Kuangshanotreta/algae malongitubus association represents both the first and oldest evidence into the enigmatic paleoecology of the diverse acrotretoid linguliformean stock that comprises an important component of the Cambrian evolutionary fauna, and sheds light on medium-high levels of secondary tiering (+5 to +10 cm) Cambrian soft substrate suspension-feeding communities. When compared to other Chengjiang brachiopods, the miniature morphology and concomitant weight reduction of the shell of K. malungensis may be a good adaption to a suspended epifaunal tiering life style. We infer that the diversification of micromorphic and miniaturized acrotretoids that occurred from the Middle Cambrian to Early Ordovician may be the result of the increased availability of habitable surfaces provided by high levels of tiering in new types of ecological spaces.

  • 30. Womack, Thomas
    et al.
    Slater, Ben
    Stevens, Lidian
    Anderson, Lyall
    Hilton, Jason
    First cladoceran fossils from the Carboniferous: palaeoenvironmental and evolutionary implications2012In: Palaeogeography, Palaeoclimatology, Palaeoecology, ISSN 0031-0182, E-ISSN 1872-616X, Vol. 344, p. 39-48Article in journal (Refereed)
    Abstract [en]

    A new cladoceran crustacean, Ebullitiocaris elatus sp. nov., is described from the Carboniferous. This unusual occurrence originates from an ex situ chert-mineralised cobble collected from beach shingle at Sandsend, Whitby, North Yorkshire. Previous biostratigraphic analysis of the micro- and megaspores from fertile plant remains associated with E. elatus restricts the fossils to an Early Mississippian to Middle Pennsylvanian age. The fossil cladocerans occur individually and in clusters and consist of a thin, oval carapace, elliptical in longitudinal section, bilaterally symmetrical, with an anterior cavity. The head overlaps the anterior cavity and is external to the carapace. Soft tissues preserved within the anterior cavity include thin, delicate thoracic appendages within the carapace and paired second antennae that extend anteriorly from the dorsal carapace cavity. These have at least six branches with segmented hair-like protrusions. The head bears a single oval compound eye with a vertically orientated long axis. A cladoceran identity is demonstrated by the univalve carapace and external head that differentiates it from the Ostracoda and Conchostraca. This is only the second record of a Palaeozoic fossil cladoceran, both recognised from sites of exceptional preservation in wetland ecosystems where they constitute an important faunal element. E. elatus is significant as it documents additional diversity during the early evolutionary history of the Cladocera, but also confirms morphological stasis within the group, sharing many of its characteristics with extant Cladocera adapted to algal grazing in freshwater habitats.

  • 31. Zaton, Michal
    et al.
    Niedzwiedzki, Grzegorz
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Organismal Biology, Evolution and Developmental Biology.
    Marynowski, Leszek
    Benzerara, Karim
    Pott, Christian
    Cosmidis, Julie
    Krzykawski, Tomasz
    Filipiak, Pawel
    Coprolites of Late Triassic carnivorous vertebrates from Poland: An integrative approach2015In: Palaeogeography, Palaeoclimatology, Palaeoecology, ISSN 0031-0182, E-ISSN 1872-616X, Vol. 430, p. 21-46Article in journal (Refereed)
    Abstract [en]

    Vertebrate coprolites derived from Upper Triassic terrestrial deposits of southern Poland have been subjected to various analytical methods in order to retrieve information about their composition, producer's diet and nature of the microscopic structures preserved in the groundmass. Morphologically, the coprolites have been classified into four morphotypes, of which only three were further analysed due to their good state of preservation. Their groundmass are composed of francolite, a carbonate-rich apatite, in which abundant coccoid structures are preserved. Based on various microscopic and organic geochemical techniques, they are interpreted as fossilized bacteria which could have mediated the phosphatization of the faeces. The thin sectioning revealed that the coprolites consist of those containing exclusively bone remains, and those preserving both bone and plant remains. Those coprolites preserving only vertebrate remains are suggestive for exclusive carnivorous diet of the producers. However, the interpretation of coprolites consisting of both vertebrate and plant remains is more debatable. Although they may attest to omnivory, it cannot be excluded that potential producers were carnivorous and occasionally ingested plants, or accidentally swallowed plant material during feeding. The latter may involve predation or scavenging upon other herbivorous animals. The potential producers may have been animals that foraged in or near aquatic habitats, such as semi-aquatic archosaurs and/or temnospondyls. This is supported by the presence of ostracode and other aquatic arthropod remains, and fish scales within the coprolites, as well as by the presence of specific biomarkers such as phytanic and pristanic acids, which are characteristic constituents of fish oil. The preservation of such labile organic compounds as sterols, palmitin, stearin or levoglucosan attests for rapid, microbially-mediated mineralization of the faeces at very early stages of diagenesis.

  • 32.
    Zhang, Zhifei
    et al.
    Early Life Institute, State Key Laboratory of Continental Dynamics, Northwest University, Xi'an, 710069, China.
    Holmer, Lars E.
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, Palaeobiology.
    Robson, Sean P.
    The Manitoba Museum, 190 Rupert Avenue, Winnipeg, Manitoba, Canada.
    Hu, Shixue
    Yunnan Geological Survey &Yunnan Institute of Geological Science, No. 87, Dongfeng Lane, East Dongfeng Road, Kunming, 650051, Yunnan Province, China.
    Wang, Xiangren
    Early Life Institute, State Key Laboratory of Continental Dynamics, Northwest University, Xi'an, 710069, China.
    Wang, Haizhou
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, Palaeobiology.
    First record of repaired durophagous shell damages in Early Cambrian lingulate brachiopods with preserved pedicles2011In: Palaeogeography, Palaeoclimatology, Palaeoecology, ISSN 0031-0182, E-ISSN 1872-616X, Vol. 302, no 3-4, p. 206-212Article in journal (Refereed)
    Abstract [en]

    Durophagy, the macro-predatory consumption of hard-shelled organisms, has been proposed as an important driving and selective force ("arms race") responsible for the explosive advent of Cambrian skeleton-bearing animals. Nevertheless, the direct evidence of durophagous predation is mostly restricted to borings or drillholes in skeletons at around the Ediacaran-Cambrian transition. In contrast, pre-ingestive breakage or crushing of shell, another important type of durophagous predation evidence, is very rarely fossilized. Here we present the first evidence of durophagous shell-breaking in an exceptionally preserved pedunculate lingulate brachiopod from the Lower Cambrian Wulongqing Formation (Series 2, early Stage 4), Yunnan, southern China. The repaired shells of Diandongia pista all have elongate (up to 36 mm) pedicles that demonstrate that they survived the failed predation and remained in situ. The bite embayment shows three sets of distinctive drape-like convex arcs of shell repairs, suggesting that the specific drape-like ornamentation usually seen in lingulate shells could be taken as reparative responses to shell damage and malformation. Discovery of sublethal shell damage demonstrates that durophagous predators may have caused an increasing predation pressure on brachiopods since the Canglangpuian Stage (Series 2, Stage 4). In contrast there are no records of durophagous shell-breaking recognized from thousands of Chengjiang (Series 2, Stage 3) specimens of D. pista with fully developed organization of tissues and organ system. It is therefore assumed that that predation was of little importance to the earliest evolution of Cambrian lingulates.

  • 33.
    Zhang, Zhi-liang
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, Palaeobiology. Northwest Univ, Shaanxi Key Lab Early Life & Environm, State Key Lab Continental Dynam, Xian 710069, Shaanxi, Peoples R China.;Northwest Univ, Dept Geol, Xian 710069, Shaanxi, Peoples R China..
    Skovsted, Christian B.
    Northwest Univ, Shaanxi Key Lab Early Life & Environm, State Key Lab Continental Dynam, Xian 710069, Shaanxi, Peoples R China.;Northwest Univ, Dept Geol, Xian 710069, Shaanxi, Peoples R China.;Swedish Museum Nat Hist, Dept Palaeobiol, Box 50007, SE-10405 Stockholm, Sweden..
    Zhang, Zhi-fei
    Northwest Univ, Shaanxi Key Lab Early Life & Environm, State Key Lab Continental Dynam, Xian 710069, Shaanxi, Peoples R China.;Northwest Univ, Dept Geol, Xian 710069, Shaanxi, Peoples R China..
    A hyolithid without helens preserving the oldest hyolith muscle scars; palaeobiology of Paramicrocornus from the Shujingtuo Formation (Cambrian Series 2) of South China2018In: Palaeogeography, Palaeoclimatology, Palaeoecology, ISSN 0031-0182, E-ISSN 1872-616X, Vol. 489, p. 1-14Article in journal (Refereed)
    Abstract [en]

    The hyolithid Paramicrocornus zhenbaensis from the lower Cambrian (Cambrian Series 2) Shuijingtuo Formation of southern Shaanxi and western Hubei provinces of the Yangtze Platform is well-preserved in three dimensions. The morphology of the conch and operculum of P.zhenbaensis shows that this species lacked helens, which are considered to be characteristic of hyolithids and hence Paramicrocornus may belong to a sister group of other hyolithids. The shell structure of P.zhenbaensis reveals close similarities to the shell structure of other hyolithids. Furthermore, the smaller size and non-radial orientation of tubules in the shell structure of the operculum also differ from that in orthothecid hyoliths, suggesting that this characteristic may be used to differentiate hyolithids and orthothecids. The phosphatized opercula of P. zhenbaensis exhibit a pair of muscle scars located close to the apex of the internal surface. These muscle scars, as well as similar structures in other hyolithids, probably served as attachment sites of muscles controlling the retraction of the tentaculate feeding organ recently discovered in hyolithids. Without helens, P. zhenbaensis may have been sessile with the conch partly buried in the sea floor. (C) 2017 Published by Elsevier B.V.

  • 34.
    Zivile, Zigaite
    et al.
    University of Lille.
    Joachimski, M. M.
    Lehnert, O.
    Brazauskas, A.
    δ 18O composition of conodont apatite indicates climatic cooling during the middle Pridoli2010In: Palaeogeography, Palaeoclimatology, Palaeoecology, ISSN 0031-0182, E-ISSN 1872-616X, Vol. 294, p. 242-247Article in journal (Refereed)
    Abstract [en]

    Phosphatic microfossils, such as conodonts and fish microremains (dermal scales) from the upper Silurian(Pridoli) of Lithuania have been studied for their oxygen isotope composition. The conodont colour alterationindex of the biogenic apatite did not exceed 1.5 reflecting only a minor thermal alteration. Conodontδ18Oapatite values range from 17.7 to 19.2‰ V-SMOW, with the average values around 18.3‰. Fossil apatite offish exoskeleton microremains from the same samples have lower δ18Oapatite values ranging from 15.2 to17.4‰ V-SMOW, with the average values around 16.3‰ V-SMOW. Palaeoseawater temperatures calculatedfrom conodont apatite δ18O range from 24.8–31.5 °C, those derived from fish δ18O give approximately 10 °Chigher temperatures ranging from 32.6 to 38.1 °C. The lower δ18Oapatite values of fish apatite and thus theunrealistic high palaeotemperatures are interpreted as a result of diagenetic alteration. A significant positiveshift in conodont apatite δ18O of +1.1‰ at the boundary between the Vievis and Lapės formations isobserved, coinciding with a major facies change. It is interpreted as a mid-Pridoli event within theOzarkodina eosteinhornensis Bizone, or the Ozarkodina remscheidensis Biozone reflecting a major coolingevent, which may have resulted in the formation of an ice sheet in high latitudes and a glacio-eustatic sealevelfall.

  • 35. Zyla, Dagmara
    et al.
    Wegierek, Piotr
    Owocki, Krzysztof
    Niedzwiedzki, Grzegorz
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Organismal Biology, Evolution and Developmental Biology.
    Insects and crustaceans from the latest Early-early Middle Triassic of Poland2013In: Palaeogeography, Palaeoclimatology, Palaeoecology, ISSN 0031-0182, E-ISSN 1872-616X, Vol. 371, p. 136-144Article in journal (Refereed)
    Abstract [en]

    Two stratigraphical horizons in the Palegi clay-pit, a new Triassic paleontological site within Buntsandstein deposits (latest Olenekian-early Anisian in age) in the Holy Cross Mountains (Poland), have yielded arthropod faunas comprising ca. 400 fossil specimens assigned to two subphyla: Crustacea (class Branchiopoda and Maxillopoda) and Hexapoda (class Insecta). The Palegi arthropod assemblage is similar to that described from the Middle Triassic of France and Germany but is dominated by remains of conchostracans and cockroaches. This new fauna expands our knowledge of the latest Early-early Middle Triassic diversity of insects and freshwater arthropods in the Germanic Basin. The newly discovered fauna represents one of the oldest Mesozoic records of insects described from the Buntsandstein fades of Europe, and provides important information to better appreciate the process of ecosystem recovery after the Permian-Triassic extinction.

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