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  • 1. Adrian, Brent
    et al.
    Werdelin, Lars
    Naturhistoriska riksmuseet, Enheten för paleobiologi.
    Grossman, Aryeh
    New Miocene Carnivora (Mammalia) from Moruorot and Kalodirr, Kenya2018Inngår i: Palaeontologia Electronica, ISSN 1935-3952, E-ISSN 1094-8074, Vol. 21Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

     We describe new carnivoran fossils from Kalodirr and Moruorot, two late Early

    Miocene sites in the Lothidok Formation of West Turkana, Kenya. The fossils include a

    new species of viverrid, Kichechia savagei  sp. nov., a new genus and species of felid,

    Katifelis nightingalei  gen. et sp. nov., and an unidentified musteloid. We also report

    new records of the amphicyonid Cynelos macrodon. These new fossils increase the

    known diversity of African Early Miocene carnivorans and highlight regional differences

    in Africa.

    Fulltekst (pdf)
    fulltext
  • 2.
    Adroit, Benjamin
    et al.
    Naturhistoriska riksmuseet, Enheten för paleobiologi.
    Grímsson, Friðgeir
    University of Vienna, Department of Botany and Biodiversity Research, 1030 Vienna, Austria.
    Suc, Jean-Pierre
    Sorbonne Université, CNRS-INSU, Institut des Sciences de la Terre Paris, ISTeP UMR7193, 75005 Paris, France.
    Escarguel, Gilles
    Laboratoire d'Ecologie des Hydrosystèmes Naturels et Anthropisés UMR CNRS 5023 LEHNA, Université Claude Bernard Lyon 1, France.
    Zetter, Reinhard
    University of Vienna, Department of Palaeontology, 1090 Vienna, Austria.
    Bouchal, Johannes M.
    University of Vienna, Department of Botany and Biodiversity Research, 1030 Vienna, Austria.
    Fauquette, Séverine
    ISEM, Univ Montpellier, CNRS, EPHE, IRD, Montpellier, France.
    Zhuang, Xin
    Institute for Atmospheric and Earth System Research (INAR), University of Helsinki, Finland.
    Djamali, Morteza
    Institut Méditerranéen de Biodiversité et d'Ecologie–IMBE (Aix Marseille Univ, Avignon Université, CNRS, IRD), Europôle de l'Arbois, Aix-en-Provence, France.
    Are morphological characteristics of Parrotia (Hamamelidaceae) pollen species diagnostic?2022Inngår i: Review of Palaeobotany and Palynology, ISSN 0034-6667, E-ISSN 1879-0615, Vol. 307, s. 104776-104776, artikkel-id 104776Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Parrotia persica is one of the most notable endemic relict tree species growing in the Hyrcanian forest at the southern Caspian Sea. The recent discovery of sibling species Parrotia subaequalis, occurring in the temperate forests of south-eastern China, offers the opportunity to compare their morphology and ecological preferences and to dig deeper into the paleophytogeographic history of the genus from a perspective. Since pollen morphology of these species would be essential to unravel the origin and evolution of these Arcto-Tertiary species, the present study aimed to investigate whether it is possible to segregate pollen from these two species. Therefore, a detailed combined light- and scanning electron microscopy-based pollen-analysis of each taxon was conducted, the pollen was described, measured, and compared using statistical approaches and principal component analyses to establish unbiased results. The correlation-based principal component analysis achieved for each species shows an overall good superposition of pollen grains measured in equatorial and polar views in the first principal plane, revealing that the P. persica pollen is morphometrically as homogeneous as that of P. subaequalis. Then, the significant difference, mainly driven by lumen density, has been highlighted between the two species. Ultimately, the cross-validation of the resulting two-species linear discriminants classifier shows that based upon this reference dataset, (sub)fossil pollen grain can now be confidently assigned to either of the two species with an 85.8% correct-assignment rate. This opens new doors in the affiliation of fossil Parrotia pollen and suggests that previous pollen records need to be revised.

    Fulltekst (pdf)
    fulltext
  • 3. Adroit, Benjamin
    et al.
    Teodoridis, Vasilis
    Güner, H. Tuncay
    Denk, Thomas
    Naturhistoriska riksmuseet, Enheten för paleobiologi.
    Patterns of insect damage types reflect complex environmental signal in Miocene forest biomes of Central Europe and the Mediterranean2021Inngår i: Global and Planetary Change, ISSN 0921-8181, E-ISSN 1872-6364, Vol. 199, artikkel-id 103451Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Ecosystems are defined by the community of living organisms and how they interact together and with theirenvironment. Insects and plants are key taxa in terrestrial ecosystems and their network determines the trophicstructure of the environment. However, what drives the interactions between plants and insects in modern andfossil ecosystems is not well understood. In this study, we analyzed insect damage richness and frequency in 5000 fossil leaves deposited during the early Miocene at 20–17 Ma along a latitudinal gradient from Europe (twolocalities in Czech Republic) to Turkey (one locality) in a temperate climate setting. Damage frequency wasmainly linked with abiotic factors (temperature, precipitation seasonality) whereas damage richness was mainlylinked with biotic factors (plant richness, biome). Univariate analysis of insect damage types consistently suggested closer trophic similarity between the Mediterranean and either the one or the other Central European plant assemblage. In contrast, multivariate analysis of all insect damage types indicated closer similarity between the two Central European sites highlighting the importance of biogeographic legacy and geographic closeness to the plant-insect interaction patterns. Our results underscore the high complexity of the herbivory network andcall for careful interpretations of plant-insect interaction patterns in palaeoecological studies. Finally, comparing the trophic similarity between different localities using total evidence plots as done in this work might be apromising complementary method in comparative studies of plant-insect interactions.

    Fulltekst (pdf)
    Adroit et al. 2021
  • 4.
    Amano, Kazutaka
    et al.
    Department of Geoscience, Joetsu University of Education, Joetsu, Japan.
    Kiel, Steffen
    Naturhistoriska riksmuseet, Enheten för paleobiologi.
    Hryniewicz, Krzysztof
    Institute of Paleobiology, Polish Academy of Sciences, Warszawa, Poland.
    Jenkins, Robert
    College of Science and Engineering, Kanazawa University, Kanazawa, Japan.
    Bivalvia in ancient hydrocarbon seeps2022Inngår i: Ancient Hydrocarbon Seeps / [ed] Kaim, Andrzej; Landman, Neil H.; Cochran, J. Kirk, Berlin: Springer Berlin/Heidelberg, 2022, s. 267-321Kapittel i bok, del av antologi (Fagfellevurdert)
    Abstract [en]

    Bivalves are an important part of the methane seep fauna ever since seeps appeared in the geologic record. The chronostratigraphic ranges of seep-inhabiting chemosymbiotic bivalves show an overall increase in diversity at seeps since the Paleozoic. The most common group at Paleozoic and early Mesozoic seeps are modiomorphids, with a few additional records of solemyids and anomalodesmatans. The most common infaunal chemosymbiotic bivalve taxa at modern seeps, lucinids and thyasirids, appeared at seeps in the Late Jurassic and earliest Cretaceous. They diversified during the Cretaceous synchronous with the peak of the “Mesozoic Marine Revolution” and first occurrences of gastropod predatory drill holes in the shells of seep-inhabiting bivalves, soon after the appearance of these gastropods in the mid-Cretaceous. The two dominant bivalve clades of the modern vent and seep fauna, bathymodiolins and vesicomyids, appeared in the Eocene. Their origin has been linked to a deep-water extinction event at the Paleocene-Eocene Thermal Maximum. However, the fossil record of chemosymbiotic bivalves at seeps during this time interval does not display any extinction. Rather, the mid-Eocene appearance of semi-infaunal and epifaunal bivalves such as bathymodiolins and vesicomyids might be linked to a dramatic rise in seawater sulfate concentrations at this time.

  • 5.
    Anderson, Heidi
    et al.
    Dorrigo, NSW, Australia.
    David J. Batten, David
    Manchester University.
    Cantrill, David
    National Herbarium of Victoria, Royal Botanic Gardens Melbourne.
    Cleal, Christopher
    Museum of Wales.
    Susanne Feist-Burkhardt, Susanne
    SFB Geological Consulting & Services, Odenwaldstrasse 18, D-64372 Ober-Ramstadt, Germany.
    Fensome, Robert
    Natural Resources Canada.
    Head, Martin
    Brock University, Canada.
    Herendeen, Patrick
    Chicago Botanuic Garden.
    Jaramillo, Carlos
    Smithsonian Institution.
    Kvaček, Jiří
    Czech National Museum, Prague.
    McLoughlin, Stephen
    Naturhistoriska riksmuseet, Enheten för paleobiologi.
    Skog, Judith
    George Mason University.
    Takahashi, Masamichi
    Niigata University.
    Wicander, Reed
    Department of Earth and Atmospheric Sciences, Central Michigan University .
    (087–090) Proposal to treat the use of a hyphen in the name of a fossil-genus as an orthographical error2015Inngår i: Taxon, ISSN 0040-0262, E-ISSN 1996-8175Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    We propose modifications to the Code such that use of a hyphen in the name of a fossil-genus is treated as an error to be corrected by deletion of the hyphen. This will circumvent the need to conserve the numerous de-hyphenated names against unused hyphenated forms. We propose changes to Art. 60 of the Code to allow this correction, and the addition of a phrase in Art. 20 to add clarity to the naming of fossil-genera.

    Fulltekst (pdf)
    fulltext
  • 6.
    Andersson, Ulf Bertil
    et al.
    Committee for Geological Nomenclature, Swedish National Committee for Geology, Royal Swedish Academy of Sciences, Stockholm, Sweden.
    Jansson, Nils
    Committee for Geological Nomenclature, Swedish National Committee for Geology, Royal Swedish Academy of Sciences, Stockholm, Sweden.
    Wickström, Linda
    Committee for Geological Nomenclature, Swedish National Committee for Geology, Royal Swedish Academy of Sciences, Stockholm, Sweden.
    Bergman, Stefan
    Committee for Geological Nomenclature, Swedish National Committee for Geology, Royal Swedish Academy of Sciences, Stockholm, Sweden.
    Kumpulainen, Risto
    Committee for Geological Nomenclature, Swedish National Committee for Geology, Royal Swedish Academy of Sciences, Stockholm, Sweden.
    Johnson, Mark
    Committee for Geological Nomenclature, Swedish National Committee for Geology, Royal Swedish Academy of Sciences, Stockholm, Sweden.
    Olvmo, Mats
    Committee for Geological Nomenclature, Swedish National Committee for Geology, Royal Swedish Academy of Sciences, Stockholm, Sweden.
    McLoughlin, Stephen
    Naturhistoriska riksmuseet, Enheten för paleobiologi. Committee for Geological Nomenclature, Swedish National Committee for Geology, Royal Swedish Academy of Sciences, Stockholm, Sweden.
    Calner, Mikael
    Committee for Geological Nomenclature, Swedish National Committee for Geology, Royal Swedish Academy of Sciences, Stockholm, Sweden.
    Emendment to the term complex in: “Guide for geological nomenclature in Sweden” (Kumpulainen 2016)2022Inngår i: GFF, ISSN 1103-5897, E-ISSN 2000-0863, Vol. 144, nr 3-4, s. 151-151Artikkel i tidsskrift (Annet vitenskapelig)
    Abstract [en]

    Since the publication of Kumpulainen (2016), the Committeehave been alerted by the investigation and subsequent changesto the North American Stratigraphic Code concerning thelithodemic unit“complex”(Easton et al.2016; North Ameri-can Commission on Stratigraphic Nomenclature (NACSN)2017). These changes concern the introduction of the nomen-clature unit“Intrusive Complex”. In the original version(NACSN1983), as well as in the Swedish Guide for nomencla-ture (Kumpulainen2016), the unit“complex”is defined ascontaining at least two genetic classes of rocks, i.e., igneous,sedimentary, or metamorphic.

    Fulltekst (pdf)
    fulltext
  • 7.
    Bagriy, I.D.
    et al.
    Institute of Geological sciences, of the National Academy of Sciences, Ukraine.
    Repkin, O.O.
    Institute of Geological sciences, of the National Academy of Sciences, Ukraine.
    Zabulonov, Yu.L.
    Institute of Geological sciences, of the National Academy of Sciences, Ukraine.
    Vyzhva, S.V.
    Institute of Geological sciences, of the National Academy of Sciences, Ukraine.
    Khrushchev, D.P.
    Institute of Geological sciences, of the National Academy of Sciences, Ukraine.
    Payuk, S.O.
    Institute of Geological sciences, of the National Academy of Sciences, Ukraine.
    Shchurov, I.V.
    Institute of Geological sciences, of the National Academy of Sciences, Ukraine.
    Gafych, I.P.
    Institute of Geological sciences, of the National Academy of Sciences, Ukraine.
    Kryl, Y.M.
    Institute of Geological sciences, of the National Academy of Sciences, Ukraine.
    Rusakov, O.M.
    Institute of Geological sciences, of the National Academy of Sciences, Ukraine.
    Popov, O.O.
    Institute of Geological sciences, of the National Academy of Sciences, Ukraine.
    Kovach, V.O.
    Institute of Geological sciences, of the National Academy of Sciences, Ukraine.
    Maslun, N.V.
    Institute of Geological sciences, of the National Academy of Sciences, Ukraine.
    Ivanik, O.M.
    Institute of Geological sciences, of the National Academy of Sciences, Ukraine.
    Shevchuk, O.A.
    Naturhistoriska riksmuseet, Enheten för paleobiologi. Stockholm University; Institute of Geological sciences, of the National Academy of Sciences, Ukraine.
    Leskiv, I.V.
    Institute of Geological sciences, of the National Academy of Sciences, Ukraine.
    Rudenko, Y.F.
    Institute of Geological sciences, of the National Academy of Sciences, Ukraine.
    Semenyuk, V.G.
    Institute of Geological sciences, of the National Academy of Sciences, Ukraine.
    Sira, N.V.
    Institute of Geological sciences, of the National Academy of Sciences, Ukraine.
    Solodkyi, E.V.
    Institute of Geological sciences, of the National Academy of Sciences, Ukraine.
    Grishanenko, V.P.
    Institute of Geological sciences, of the National Academy of Sciences, Ukraine.
    Dubosarskyi, V.R.
    Institute of Geological sciences, of the National Academy of Sciences, Ukraine.
    Dovbysh, N.S.
    Institute of Geological sciences, of the National Academy of Sciences, Ukraine.
    Mamyshev, I.E.
    Institute of Geological sciences, of the National Academy of Sciences, Ukraine.
    Lihvan, V.M.
    Institute of Geological sciences, of the National Academy of Sciences, Ukraine.
    Kuzmenko, S.O.
    Institute of Geological sciences, of the National Academy of Sciences, Ukraine.
    Koval, A.M.
    Institute of Geological sciences, of the National Academy of Sciences, Ukraine.
    Starodubets, K.M.
    Institute of Geological sciences, of the National Academy of Sciences, Ukraine.
    H2 - Ecological source of decarbonization - The path to energy independence of Ukraine2023Bok (Annet vitenskapelig)
    Abstract [en]

    The research studied the pressing problem of the fuel and energy strategy of the XXI century. For the first time, there was shown the diversity of the authors' approach to theoretical and applied problems of hydrogen energy. General issues of fundamental and applied aspects of hydrogen origin were covered. The study provides the results of scientific developments on hydrogen mapping performed within the framework of scientific and practical exploratory and geo-ecological research on more than 200 hydrocarbon objects both on land (including mining fields) and in marine water areas. Prognostic and search system criteria were substantiated, with hydrogen being used for the first time as a component of the complex of methodical solutions in the search practice. The research showed the importance of solving the problem of geo-ecological processes and accidents in mine workings and wells, connected to numerous disasters. According to numerous studies of mine massives, a set of preventive measures and criteria that prevent explosive processes was provided.The presence of a unique complex of natural components of hydrogen technology, solar and wind energy resources and fresh waters of the Danube lakes and the Danube was stated.The study emphasises the decisive role of Ukraine in the competition for primacy in scientific developments. For the first time in world practice, the implementation of global projects for the extraction and production of green and white hydrogen was substantiated.The technology was tested on numerous hydrocarbon deposits, water resources and mine workings and therefore has all the prospects for the effective application in the search and extraction of hydrogen. This monograph can be useful and informative for specialists in the fields of oil and gas geology, general and regional geology, hydrology, environmental protection, as well as for the students and postgraduate students of fuel and energy, oil and gas geological and hydrological areas, as well as for domestic and foreign investors.

    Fulltekst (pdf)
    fulltext
  • 8.
    Bagriy, Ihor Dmytrovych
    et al.
    Institute of Geological Sciences of the National Academy of Sciences of Ukraine.
    Riepkin, Oleksandr Oleksandrovуch
    Ukrainian Hydrogen Council.
    Zabulonov, Yuriy Leonidovych
    Institute of Environmental Geochemistry of the NAS of Ukraine.
    Vyzhva, Sergiy Andriyovych
    Institute of Geology of Taras Shevchenko Kyiv National University.
    Khrushchev, Dmytro Pavlovуch
    National Academy of Sciences of Ukraine.
    Rusakov, Oleg Maksimovich
    Institute of Geophysics of NAS of Ukraine.
    Popov, Oleksandr Oleksandrovych
    Institute of Geochemistry of the Environment, NAS of Ukraine.
    Maslun, Ninel Volodymyrivna
    Institute of Geological Sciences of the NAS of Ukraine.
    Ivanik, Olena Mykhailivna
    Department of General and Historical Geology, Institute of Geology, Taras Shevchenko National University of Kyiv, Ukraine.
    Kovach, Valeriya Omelanivna
    Institute of Environmental Geochemistry of the NAS of Ukraine.
    Shevchuk, Olena
    Naturhistoriska riksmuseet, Enheten för paleobiologi. Ukrainian Academy of Sciences; Stockholm University.
    Kryl, Iaroslav Mykolayovych
    Voden Ukrainy.
    Payuk, Serhii Oleksiyovych
    State Commission of Ukraine on Mineral Reserves.
    Shchurov, Ihor Vyacheslavovуch
    DTEK Naftogaz.
    Hafуch, Ivan Petrovych
    DTEK Naftogaz.
    Leskiv, Ihor Volodymyrovych
    UNGA.
    Rudenko, Yury Fedorovych
    Scientific and Engineering Center of Radio-Hydrogeoecological Polygon Research of the National Academy of Sciences of Ukraine.
    Semenyuk, Volodymyr Grуgorovуch
    Smart Energy.
    Sira, Nataliia Vasilivna
    Ukrainian Geological Research and Production Center.
    Grishanenko, Volodymyr Petrovych
    Center of Oil and Gas Resources.
    Solodkyy, Evgeniy Valeriyovych
    Naftogaz LLC.
    Dubosarsky, Viktor Rudolfovich
    Institute of Geological Sciences of the National Academy of Sciences of Ukraine.
    Dovbysh, Nina Serhiivna
    Institute of Geological Sciences of the NAS of Ukraine.
    Mamyshev, Ihor Evgeniyovych
    Institute of Geological Sciences of the NAS of Ukraine.
    Lihvan, Vadim Maksymovich
    Plativske LLC.
    Kuzmenko, Svyatoslav Oleksandrovich
    Institute of Geological Sciences of the NAS of Ukraine.
    Koval, Anatoly Mykhailovych
    Naftogaz of Ukraine.
    Starodubets, Kyrylо Mykolayovych
    Institute of Geological Sciences of National Academy of Sciences of Ukraine.
    Development and implementation of monitoring of corrosion processes of hydrogen degasation in embrillation zones during the operation of gas pipeline2023Inngår i: Environmental and Energy Challenges of the XXI Century. Global Projects. Ways of Implementation / [ed] I.D. Bagriy, Kyiv: Institute of Geological Sciences of the National Academy of Sciences of Ukraine , 2023, s. 254-286Kapittel i bok, del av antologi (Fagfellevurdert)
    Abstract [en]

    Pipelines for oil and gas create significant risks of destruction in the systems of industrial and main transportation of hydrocarbons in the presence of corrosion-embrittlement of metal. According to many researchers one of the main reasons for this process is in the area of hydrogen anomalies. It occurs under insulating coating. Insulating coating on the pipeline is peeled off from the metal in such places. Microcracks and pores appear; then moisture spreads to outer surface of the pipe and causes corrosion processes — embrittlement. In addition, it is not excluded that corrosion is intensified due to electrochemical processes and due to undercurrents of gaseous diffusion of hydrogen gas from the mantle strata formed in the areas of the pipeline location. Hydrogen is extremely permeable gas. It leads to swelling, insulation peeling off and defects expanding. The situation creates possibility for moisture penetration to the pipes surface. It also directly affects strength of the metal causing corrosion, cracking and embrittlement. Results of the studies show that embrittlement processes take place mostly in the areas where pipelines pass through oil and gas-bearing structures. In such places hydrogen exits are recorded.

    Fulltekst (pdf)
    fulltext
  • 9.
    Bagriy, Ihor Dmytrovych
    et al.
    Institute of Geological Sciences of the National Academy of Sciences of Ukraine.
    Riepkin, Oleksandr Oleksandrovуch
    Ukrainian Hydrogen Council.
    Zabulonov, Yuriy Leonidovych
    Institute of Environmental Geochemistry of the NAS of Ukraine.
    Vyzhva, Sergiy Andriyovych
    Institute of Geology of Taras Shevchenko Kyiv National University.
    Khrushchev, Dmytro Pavlovуch
    National Academy of Sciences of Ukraine.
    Rusakov, Oleg Maksimovich
    Institute of Geophysics of NAS of Ukraine.
    Popov, Oleksandr Oleksandrovych
    Institute of Geochemistry of the Environment, NAS of Ukraine.
    Maslun, Ninel Volodymyrivna
    Institute of Geological Sciences of the NAS of Ukraine.
    Ivanik, Olena Mykhailivna
    Department of General and Historical Geology, Institute of Geology, Taras Shevchenko National University of Kyiv, Ukraine.
    Kovach, Valeriya Omelanivna
    Institute of Environmental Geochemistry of the NAS of Ukraine.
    Shevchuk, Olena
    Naturhistoriska riksmuseet, Enheten för paleobiologi. Ukrainian Academy of Sciences; Stockholm University.
    Kryl, Iaroslav Mykolayovych
    Voden Ukrainy.
    Payuk, Serhii Oleksiyovych
    State Commission of Ukraine on Mineral Reserves.
    Shchurov, Ihor Vyacheslavovуch
    DTEK Naftogaz.
    Hafуch, Ivan Petrovych
    DTEK Naftogaz.
    Leskiv, Ihor Volodymyrovych
    UNGA.
    Rudenko, Yury Fedorovych
    Scientific and Engineering Center of Radio-Hydrogeoecological Polygon Research of the National Academy of Sciences of Ukraine.
    Semenyuk, Volodymyr Grуgorovуch
    Smart Energy.
    Sira, Nataliia Vasilivna
    Ukrainian Geological Research and Production Center.
    Grishanenko, Volodymyr Petrovych
    Center of Oil and Gas Resources.
    Solodkyy, Evgeniy Valeriyovych
    Naftogaz LLC.
    Dubosarsky, Viktor Rudolfovich
    Institute of Geological Sciences of the National Academy of Sciences of Ukraine.
    Dovbysh, Nina Serhiivna
    Institute of Geological Sciences of the NAS of Ukraine.
    Mamyshev, Ihor Evgeniyovych
    Institute of Geological Sciences of the NAS of Ukraine.
    Lihvan, Vadim Maksymovich
    Plativske LLC.
    Kuzmenko, Svyatoslav Oleksandrovich
    Institute of Geological Sciences of the NAS of Ukraine.
    Koval, Anatoly Mykhailovych
    Naftogaz of Ukraine.
    Starodubets, Kyrylо Mykolayovych
    Institute of Geological Sciences of National Academy of Sciences of Ukraine.
    Gas dynamic phenomena (gdf) and causes of accidents at mines2023Inngår i: Environmental and Energy Challenges of the XXI Century. Global Projects. Ways of Implementation / [ed] I.D. Bagriy, Kyiv: Institute of Geological Sciences of the National Academy of Sciences of Ukraine , 2023, s. 238-253Kapittel i bok, del av antologi (Fagfellevurdert)
    Abstract [en]

    There is a problem of development and implementation of prospecting technology to ensure protection of mining products and prevent disasters during the of coal deposits. It is especially relevant now when issue of environmental protection and improving labor safety in coal mines is very acute. Development of safe search technology for coal deposits is proposed by the authors. It will allow early monitoring to identify places of possible manifestations of gas-dynamic phenomena and make operational decisions for their elimination. The technology is based on application of exploratory gas-geochemical methods for mapping places of accumulation of gas-hydrogen accumulations and their areas. It together with a complex of geological-geophysical method allows to identify areas of possible emergency processes in development zones of mine fields. Feasibility of using search technology to justify use of laying anticipatory degassing wells to prevent uncontrolled explosive processes and technical disasters was proved on large array of conducted field work of planar and profile surveys. The proposed technology was tested on numerous mining sites in the process of exploratory and ecological research in development zones of active and exhausted mine fields.

    Fulltekst (pdf)
    fulltext
  • 10.
    Bagriy, Ihor Dmytrovych
    et al.
    Institute of Geological Sciences of the National Academy of Sciences of Ukraine.
    Riepkin, Oleksandr Oleksandrovуch
    Ukrainian Hydrogen Council.
    Zabulonov, Yuriy Leonidovych
    Institute of Environmental Geochemistry of the NAS of Ukraine.
    Vyzhva, Sergiy Andriyovych
    Institute of Geology of Taras Shevchenko Kyiv National University.
    Khrushchev, Dmytro Pavlovуch
    National Academy of Sciences of Ukraine.
    Rusakov, Oleg Maksimovich
    Institute of Geophysics of NAS of Ukraine.
    Popov, Oleksandr Oleksandrovych
    Institute of Geochemistry of the Environment, NAS of Ukraine.
    Maslun, Ninel Volodymyrivna
    Institute of Geological Sciences of the NAS of Ukraine.
    Ivanik, Olena Mykhailivna
    Department of General and Historical Geology, Institute of Geology, Taras Shevchenko National University of Kyiv, Ukraine.
    Kovach, Valeriya Omelanivna
    Institute of Environmental Geochemistry of the NAS of Ukraine.
    Shevchuk, Olena
    Naturhistoriska riksmuseet, Enheten för paleobiologi. Ukrainian Academy of Sciences; Stockholm University.
    Kryl, Iaroslav Mykolayovych
    Voden Ukrainy.
    Payuk, Serhii Oleksiyovych
    State Commission of Ukraine on Mineral Reserves.
    Shchurov, Ihor Vyacheslavovуch
    DTEK Naftogaz.
    Hafуch, Ivan Petrovych
    DTEK Naftogaz.
    Leskiv, Ihor Volodymyrovych
    UNGA.
    Rudenko, Yury Fedorovych
    Scientific and Engineering Center of Radio-Hydrogeoecological Polygon Research of the National Academy of Sciences of Ukraine.
    Semenyuk, Volodymyr Grуgorovуch
    Smart Energy.
    Sira, Nataliia Vasilivna
    Ukrainian Geological Research and Production Center.
    Grishanenko, Volodymyr Petrovych
    Center of Oil and Gas Resources.
    Solodkyy, Evgeniy Valeriyovych
    Naftogaz LLC.
    Dubosarsky, Viktor Rudolfovich
    Institute of Geological Sciences of the National Academy of Sciences of Ukraine.
    Dovbysh, Nina Serhiivna
    Institute of Geological Sciences of the NAS of Ukraine.
    Mamyshev, Ihor Evgeniyovych
    Institute of Geological Sciences of the NAS of Ukraine.
    Lihvan, Vadim Maksymovich
    Plativske LLC.
    Kuzmenko, Svyatoslav Oleksandrovich
    Institute of Geological Sciences of the NAS of Ukraine.
    Koval, Anatoly Mykhailovych
    Naftogaz of Ukraine.
    Starodubets, Kyrylо Mykolayovych
    Institute of Geological Sciences of National Academy of Sciences of Ukraine.
    Justification of global natural, environmental and hydrological conditions of green hydrogen generation, accumulation and logistics ways2023Inngår i: Environmental and Energy Challenges of the XXI Century. Global Projects. Ways of Implementation / [ed] I. D. Bagriy, Kyiv: Institute of Geological Sciences of the National Academy of Sciences of Ukraine , 2023, s. 26-95Kapittel i bok, del av antologi (Fagfellevurdert)
    Abstract [en]

    The implementation of global energy projectsfor comprehensive solutions to the developmentof energy from renewable sources has all thenecessary conditions for the production, accumulationand transportation of green hydrogenin the south-west of the Odesa region, within theboundaries of the Izmail administrative districtand is timed to the floodplain of the Danube River.

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  • 11.
    Bagriy, Ihor Dmytrovych
    et al.
    Institute of Geological Sciences of the National Academy of Sciences of Ukraine.
    Riepkin, Oleksandr Oleksandrovуch
    Ukrainian Hydrogen Council.
    Zabulonov, Yuriy Leonidovych
    Institute of Environmental Geochemistry of the NAS of Ukraine.
    Vyzhva, Sergiy Andriyovych
    Institute of Geology of Taras Shevchenko Kyiv National University.
    Khrushchev, Dmytro Pavlovуch
    National Academy of Sciences of Ukraine.
    Rusakov, Oleg Maksimovich
    Institute of Geophysics of NAS of Ukraine.
    Popov, Oleksandr Oleksandrovych
    Institute of Geochemistry of the Environment, NAS of Ukraine.
    Maslun, Ninel Volodymyrivna
    Institute of Geological Sciences of the NAS of Ukraine.
    Ivanik, Olena Mykhailivna
    Department of General and Historical Geology, Institute of Geology, Taras Shevchenko National University of Kyiv, Ukraine.
    Kovach, Valeriya Omelanivna
    Institute of Environmental Geochemistry of the NAS of Ukraine.
    Shevchuk, Olena
    Naturhistoriska riksmuseet, Enheten för paleobiologi. Ukrainian Academy of Sciences; Stockholm University.
    Kryl, Iaroslav Mykolayovych
    Voden Ukrainy.
    Payuk, Serhii Oleksiyovych
    State Commission of Ukraine on Mineral Reserves.
    Shchurov, Ihor Vyacheslavovуch
    DTEK Naftogaz.
    Hafуch, Ivan Petrovych
    DTEK Naftogaz.
    Leskiv, Ihor Volodymyrovych
    UNGA.
    Rudenko, Yury Fedorovych
    Scientific and Engineering Center of Radio-Hydrogeoecological Polygon Research of the National Academy of Sciences of Ukraine.
    Semenyuk, Volodymyr Grуgorovуch
    Smart Energy.
    Sira, Nataliia Vasilivna
    Ukrainian Geological Research and Production Center.
    Grishanenko, Volodymyr Petrovych
    Center of Oil and Gas Resources.
    Solodkyy, Evgeniy Valeriyovych
    Naftogaz LLC.
    Dubosarsky, Viktor Rudolfovich
    Institute of Geological Sciences of the National Academy of Sciences of Ukraine.
    Dovbysh, Nina Serhiivna
    Institute of Geological Sciences of the NAS of Ukraine.
    Mamyshev, Ihor Evgeniyovych
    Institute of Geological Sciences of the NAS of Ukraine.
    Lihvan, Vadim Maksymovich
    Plativske LLC.
    Kuzmenko, Svyatoslav Oleksandrovich
    Institute of Geological Sciences of the NAS of Ukraine.
    Koval, Anatoly Mykhailovych
    Naftogaz of Ukraine.
    Starodubets, Kyrylо Mykolayovych
    Institute of Geological Sciences of National Academy of Sciences of Ukraine.
    Scientific justification of spatial distribution of hydrogen anomalies in the nearsurface layer of traditional and untraditional oil and gas-bearing structures and implementation of hydrogen search technology2023Inngår i: Environmental and Energy Challenges of the XXI Century. Global Projects. Ways of Implementation / [ed] I.D. Bagriy, Kyiv: Institute of Geological Sciences of the National Academy of Sciences of Ukraine , 2023, s. 96-237Kapittel i bok, del av antologi (Fagfellevurdert)
    Abstract [en]

    Long-term results of research on mapping of oil and gas-bearing areas on traditional and non-traditional objects (mine fields, shelf areas, astroblems) made it possible to create a database of system criteria for search technology of structural-thermo-atmospheric-hydrologic geochemical research (STAHGR). It is an integral part of methodological solutions complex.There hydrogen was used as the main constituent element of explosives for the first time insearch practice. There are of hydrogen concentrations obtained in the process of research into the mapping features of the oil and gas capacity of traditional and non-traditional HC (hydrocarbons). Their spectrum of research includes H2-hydrogen. Analysis of data results made it possible to single out anomalous single values in areas and in productive areas (in the absence of background) and to conduct detailed, multi-scale studies for the purpose of planar mapping on prospecting works and environmental impacts of gas dynamic phenomena (GDF) during the development of coal massifs.

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  • 12.
    Bengtson, Stefan
    et al.
    Naturhistoriska riksmuseet, Enheten för paleobiologi.
    Rasmussen, Birger
    School of Earth Sciences, The University of Western Australia, Perth.
    Zi, Jian-Wei
    State Key Laboratory of Geological Processes and Mineral Resources, China University of Geosciences, Wuhan.
    Fletcher, Ian R.
    School of Earth Sciences, The University of Western Australia, Perth.
    Gehling, James G.
    Palaeontology, South Australian Museum, Adelaide.
    Runnegar, Bruce
    Department of Earth, Planetary and Space Sciences, University of California, Los Angeles.
    Eocene animal trace fossils in 1.7-billion-year-old metaquartzites2021Inngår i: Proceedings of the National Academy of Sciences of the United States of America, ISSN 0027-8424, E-ISSN 1091-6490, Vol. 118, nr 40, s. 1-8, artikkel-id e2105707118Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The Paleoproterozoic (1.7 Ga [billion years ago]) metasedimentary rocks of the Mount Barren Group in southwestern Australia contain burrows indistinguishable from ichnogenera Thalassinoides, Ophiomorpha, Teichichnus, and Taenidium, known from firmgrounds and softgrounds. The metamorphic fabric in the host rock is largely retained, and because the most resilient rocks in the sequence, the metaquartzites, are too hard for animal burrowing, the trace fossils have been interpreted as predating the last metamorphic event in the region. Since this event is dated at 1.2 Ga, this would bestow advanced animals an anomalously early age. We have studied the field relationships, petrographic fabric, and geochronology of the rocks and demonstrate that the burrowing took place during an Eocene transgression over a weathered regolith. At this time, the metaquartzites of the inundated surface had been weathered to friable sandstones or loose sands (arenized), allowing for animal burrowing. Subsequent to this event, there was a resilicification of the quartzites, filling the pore space with syntaxial quartz cement forming silcretes. Where the sand grains had not been dislocated during weathering, the metamorphic fabric was seemingly restored, and the rocks again assumed the appearance of hard metaquartzites impenetrable to animal burrowing.

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  • 13.
    Benoit, Julien
    et al.
    University of the Witwatersrand.
    Kruger, Ashley
    Naturhistoriska riksmuseet, Enheten för paleobiologi. Swedish Museum of Natural History.
    Jirah, Sifelani
    University of the Witwatersrand.
    Fernandez, Vincent
    University of the Witwatersrand.
    Rubidge, Bruce
    University of the Witwatersrand.
    Palaeoneurology and palaeobiology of the dinocephalian Anteosaurus magnificus2021Inngår i: Acta Palaeontologica Polonica, ISSN 0567-7920, E-ISSN 1732-2421, Vol. 66, s. 29-39Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Dinocephalians (Therapsida), some of the earliest amniotes to have evolved large body size, include the carnivorous Anteosauria and mostly herbivorous Tapinocephalia. Whilst the palaeoneurology of the Tapinocephalia has been investigated in Moschognathus whaitsi, that of the Anteosauria remains completely unknown. Here we used X-ray micro-Computed Tomography to study, for the first time, the palaeoneurology of Anteosaurus magnificus. Compared to Moschognathus, we reconstruct Anteosaurus as an agile terrestrial predator based on the enlarged fossa for the floccular lobe of the cerebellum and semicircular canals of the inner ear. A major difference between the two genera resides in the orientation of the braincase, as indicated by the angle between the long axis of the skull and the plane of the lateral semicircular canal. This angle is 25° in Anteosaurus, whereas it is 65° in Moschognathus, which suggests that the braincase of the latter was remodelled as an adaptation to head-butting. This is consistent with less cranial pachyostosis and the retention of a large canine in Anteosauria, which suggests that dentition may have been used for intraspecific fighting and display in addition to trophic interactions. The evolution of a thick skull, horns, and bosses in tapinocephalids parallels the evolutionary reduction of the canine, which lead to a shift of the agonistic function from the mouth to the skull roof, as observed in extant social ungulates. Similarly, tapinocephalians may have developed complex social behaviour.

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  • 14.
    Bercovici, Antoine
    et al.
    Department of Geology, Lund University, Sölvegatan 12, SE-223 62 Lund, Sweden.
    Cui, Ying
    Department of Geosciences, 512 Deike Building, The Pennsylvania State University, University Park, PA 16802, USA.
    Forel, Marie-Béatrice
    State Key Laboratory of Biogeology and Environmental Geology of Ministry of Education, China University of Geosciences, Wuhan 430074, People’s Republic of China.
    Vajda, Vivi
    Naturhistoriska riksmuseet, Enheten för paleobiologi. Department of Geology, Lund University, Sweden.
    Terrestrial paleoenvironment characterization across the Permian–Triassic boundary in South China2015Inngår i: Journal of Asian Earth Sciences, ISSN 1367-9120, Vol. 98, s. 225-246Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Well-preserved marine fossils in carbonate rocks permit detailed studies of the end-Permian extinction event in the marine realm. However, the rarity of fossils in terrestrial depositional environments makes it more challenging to attain a satisfactory degree of resolution to describe the biotic turnover on land. Here we present new sedimentological, paleontological and geochemical (X-ray fluorescence) analysis from the study of four terrestrial sections (Chahe, Zhejue, Mide and Jiucaichong) in Western Guizhou and Eastern Yunnan (Yangtze Platform, South China) to evaluate paleoenvironmental changes through the Permian–Triassic transition.

    Our results show major differences in the depositional environments between the Permian Xuanwei and the Triassic Kayitou formations with a change from fluvial–lacustrine to coastal marine settings. This change is associated with a drastic modification of the preservation mode of the fossil plants, from large compressions to small comminuted debris. Plant fossils spanning the Permian–Triassic boundary show the existence of two distinct assemblages: In the Xuanwei Formation, a Late Permian (Changhsingian) assemblage with characteristic Cathaysian wetland plants (mainly Gigantopteris dictyophylloides, Gigantonoclea guizhouensis, G. nicotianaefolia, G. plumosa, G. hallei, Lobatannularia heinanensis, L. cathaysiana, L. multifolia, Annularia pingloensis, A. shirakii, Paracalamites stenocostatus, Cordaites sp.) is identified. In the lowermost Kayitou Formation, an Early Triassic (Induan)Annalepis–Peltaspermum assemblage is shown, associated with very rare, relictual gigantopterids. Palynological samples are poor, and low yield samples show assemblages almost exclusively represented by spores. A 1 m thick zone enriched in putative fungal spores was identified near the top of the Xuanwei Formation, including diverse multicellular forms, such as Reduviasporonites sp. This interval likely corresponds to the PTB ‘‘fungal spike’’ conventionally associated with land denudation and ecosystem collapse. While the floral turnover is evident, further studies based on plant diversity would be required in order to assess contribution linked to the end-Permian mass extinction versus local paleoenvironmental changes associated with the transition between the Xuanwei and Kayitou formations.

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  • 15.
    Bergström, Jan
    et al.
    Naturhistoriska riksmuseet, Enheten för paleobiologi.
    Hou, Xian-Guang
    Yunnan University, Kunming.
    Hålenius, Ulf
    Naturhistoriska riksmuseet, Enheten för geovetenskap.
    Gut contents and feeding in the Cambrian arthropod Naraoia2007Inngår i: GFF, ISSN 1103-5897, E-ISSN 2000-0863, Vol. 129, s. 71-76Artikkel i tidsskrift (Fagfellevurdert)
  • 16.
    Bermúdez, Hermann
    et al.
    Grupo de Investigación Paleoexplorer.
    Arenillas, Ignacio
    Universidad de Zaragoza.
    Arz, José Antonio
    Universidad de Zaragoza.
    Vajda, Vivi
    Naturhistoriska riksmuseet, Enheten för paleobiologi. Department of Geology, Lund University, Sweden.
    Renne, Paul
    University of California, Berkeley.
    Gilabert, Vicente
    Universidad de Zaragoza.
    Rodríguez, José Vicente
    Grupo de Investigación Paleoexplorer.
    The Cretaceous/Paleogene Boundary Deposits on Gorgonilla Island2019Inngår i: The Geology of Colombia, Volume 3 Paleogene – Neogene / [ed] Gómez, J. & Mateus–Zabala, D., Bogota: Servi­cio Geológico Colombiano , 2019, 1, s. 1-19Kapittel i bok, del av antologi (Fagfellevurdert)
    Abstract [en]

    A ca. 20 mm thick spherule bed representing Chicxulub impact ejecta deposits and marking the Cretaceous/Paleogene (K/Pg) boundary was recently discovered on Gorgonilla Island (Gorgona National Natural Park, Pacific of Colombia). This discovery represents the first confirmed record of the K/Pg event in Colombia, South America and the eastern Pacific Ocean. The deposit consists of extraordinarily well–preserved glass spherules (microtektites and microkrystites) reaching 1.1 mm in diameter. Importantly, the Gorgonilla spherule bed is unique relative to other K/Pg boundary sites in that up to 90% of the spherules are intact and not devitrified, and the bed is virtually devoid of lithic fragments and microfossils. The spherules were deposited in a deep marine environment, possibly below the calcite compensation depth. The preservation, normal size–gradation, presence of fine textures within the spherules, and absence of bioturbation or traction transport indicate that the Gorgonilla spherules settled within a water column with minimal disturbance. The spherule bed may represent one of the first parautochthonous primary deposits of the Chicxulub impact known to date. 40Ar/39Ar dating and micropaleontological analysis reveal that the Gorgonilla spherule bed resulted from the Chicxulub impact. Intense soft–sediment deformation and bed disruption in Maastrichtian sediments of the Gorgonilla Island K/Pg section provide evidence for seismic activity triggered by the Chicxulub bolide impact, 66 million years ago. It is also notable that the basal deposits of the Danian in the Colombian locality present the first evidence of a recovery vegetation, characterized by ferns from a tropical habitat, shortly following the end–Cretaceous event.

  • 17. BERMÚDEZ,, Hermann Darío
    et al.
    ARENILLAS, Ignacio
    ARZ, José Antonio
    Vajda, Vivi
    Naturhistoriska riksmuseet, Enheten för paleobiologi. Department of Geology, Lund University, Sweden.
    RENNE, Paul R.
    GILABERT, Vicente
    RODRÍGUEZ, José Vicente
    The Cretaceous/Paleogene boundary deposits on Gorgonilla Island2018Inngår i: The Geology of Colombia: Volume  3   Paleogene – Neogene / [ed] Tapias, J.G. et al., Bogota: Servicio Geológico Colombiano , 2018, s. 1-34Kapittel i bok, del av antologi (Fagfellevurdert)
    Abstract [en]

    A ~20 mm thick spherule bed representing Chicxulub impact ejecta deposits and marking the Cretaceous/Paleogene (K/Pg) boundary was recently discovered on Gorgonilla Island (Gorgona National Natural Park, Pacific of Colombia). This discovery represents the first confirmed record of the K/Pg event in Colombia, South America and the eastern Pacific Ocean. The deposit consists of extraordinarily well–preserved glass spherules (microtektites and microkrystites) reaching 1.1 mm in diameter. Importantly, the Gorgonilla spherule bed is unique relative to other K/Pg boundary sites in that up to 90% of the spherules are intact and not devitrified, and the bed is virtually devoid of lithic fragments and microfossils. The spherules were deposited in a deep marine environment, possibly below the calcite compensation depth. The preservation, normal size–gradation, presence of fine textures within the spherules, and absence of bioturbation or traction transport indicate that the Gorgonilla spherules settled within a water column with minimal disturbance. Thus, the spherule bed may represent one of the first parautochthonous primary deposits of the Chicxulub impact known to date. 40Ar/39Ar dating and micropaleontological analysis reveal that the Gorgonilla spherule bed resulted from the Chicxulub impact. Intense soft–sediment deformation and bed disruption in Maastrichtian sediments of the Gorgonilla Island K/Pg section provide evidence for seismic activity triggered by the Chicxulub bolide impact, 66 million years ago. It is also notable that the basal deposits of the Danian in the Colombian locality present the first evidence of a recovery vegetation, characterized by ferns from a tropical habitat, shortly following the end–Cretaceous event.

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  • 18. Bibi, Faysal
    et al.
    Pante, Michael
    Souron, Antoine
    Stewart, Kathlyn
    Varela, Sara
    Werdelin, Lars
    Naturhistoriska riksmuseet, Enheten för paleobiologi.
    Boisserie, Jean-Renaud
    Fortelius, Mikael
    Hlusko, Leslea
    Njau, Jackson
    de la Torre, Ignacio
    Paleoecology of the Serengeti during the Oldowan-Acheulean transition at Olduvai Gorge, Tanzania: The mammal and fish evidence2017Inngår i: Journal of Human Evolution, ISSN 0047-2484, E-ISSN 1095-8606Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Eight years of excavation work by the Olduvai Geochronology and Archaeology Project (OGAP) has produced a rich vertebrate fauna from several sites within Bed II, Olduvai Gorge, Tanzania. Study of these as well as recently re-organized collections from Mary Leakey's 1972 HWK EE excavations here provides a synthetic view of the faunal community of Olduvai during Middle Bed II at ~1.7e1.4 Ma, an interval that captures the local transition from Oldowan to Acheulean technology. We expand the faunal list for this interval, name a new bovid species, clarify the evolution of several mammalian lineages, and record new local first and last appearances. Compositions of the fish and large mammal assemblages support previous indications for the dominance of open and seasonal grassland habitats at the margins of an alkaline lake. Fish diversity is low and dominated by cichlids, which indicates strongly saline conditions. The taphonomy of the fish assemblages supports reconstructions of fluctuating lake levels with mass die-offs in evaporating pools. The mammals are dominated by grazing bovids and equids. Habitats remained consistently dry and open throughout the entire Bed II sequence, with no major turnover or paleoecological changes taking place. Rather, wooded and wet habitats had already given way to drier and more open habitats by the top of Bed I, at 1.85e1.80 Ma. This ecological change is close to the age of the Oldowan-Acheulean transition in Kenya and Ethiopia, but precedes the local transition in Middle Bed II. The Middle Bed II largemammal community is much richer in species and includes a much larger number of large-bodied species (>300 kg) than the modern Serengeti. This reflects the severity of Pleistocene extinctions on African large mammals, with the loss of large species fitting a pattern typical of defaunation or ‘downsizing’ by human disturbance. However, trophic network (food web) analyses show that the Middle Bed II communitywas robust, and comparisons with the Serengeti community indicate that the fundamental structure of foodwebs remained intact despite Pleistocene extinctions. The presence of a generalized meateating hominin in the Middle Bed II community would have increased competition among carnivores and vulnerability among herbivores, but the high generality and interconnectedness of the Middle Bed II food web suggests this community was buffered against extinctions caused by trophic interactions.

  • 19.
    Bomfleur, Benjamin
    et al.
    Westfälische Wilhelms-Universität, Münster, Germany.
    Blomenkemper, Patrick
    Westfälische Wilhelms-Universität, Münster, Germany.
    Kerp, Hans
    Westfälische Wilhelms-Universität, Münster, Germany.
    McLoughlin, Stephen
    Naturhistoriska riksmuseet, Enheten för paleobiologi.
    Polar regions of the Mesozoic–Paleogene greenhouse world as refugia for relict plant groups2018Inngår i: Transformative Paleobotany: Papers to Commemorate the Life and Legacy of Thomas N. Taylor / [ed] Krings, M., Harper, C.J., Cúneo, N.R., Rothwell, G.W., Amsterdam: Elsevier, 2018, s. 593-611Kapittel i bok, del av antologi (Fagfellevurdert)
    Abstract [en]

    Throughout Earth history, plants were apparently less dramatically affected by global biotic crises than animals. Here, we present the unexpected occurrence of Dicroidium, the iconic plant fossil of the Gondwanan Triassic, in Jurassic strata of East Antarctica. The material consists of dispersed cuticles of three Dicroidium species, including the type species D. odontopteroides. These youngest occurrences complement a remarkable biogeographic pattern in the distribution of Dicroidium through time: the earliest records are from palaeoequatorial regions, whereas the last records are from polar latitudes. We summarize similar, relictual high-latitude occurrences in other plant groups, including lycopsids, various ‘seed ferns’, Bennettitales, and cheirolepid conifers, to highlight a common phenomenon: during times of global warmth, the ice-free high-latitude regions acted as refugia for relictual plant taxa that have long disappeared elsewhere. Eventually, such last surviving polar populations probably disappeared as they became outcompeted by newly emerging plant groups in the face of environmental change.

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  • 20.
    Bomfleur, Benjamin
    et al.
    Naturhistoriska riksmuseet, Enheten för paleobiologi.
    Decombeix, Anne-Laure
    Schwendemann, Andrew
    Escapa, Ignacio
    Taylor, Edith
    Taylor, Thomas
    McLoughlin, Stephen
    Naturhistoriska riksmuseet, Enheten för paleobiologi.
    Habit and Ecology of the Petriellales, an Unusual Group of Seed Plants from the Triassic of Gondwana2014Inngår i: International journal of plant sciences, ISSN 1058-5893, E-ISSN 1537-5315, Vol. 175, nr 9, s. 1062-1075Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Premise of research. Well-preserved Triassic plant fossils from Antarctica yield insights into the physiology of plant growth under the seasonal light regimes of warm polar forests, a type of ecosystem without any modern analogue. Among the many well-known Triassic plants from Antarctica is the enigmatic Petriellaea triangulata, a dispersed seedpod structure that is considered a possible homologue of the angiosperm carpel. However, the morphology and physiology of the plants that produced these seedpods have so far remained largely elusive.

    Methodology. Here, we describe petriellalean stems and leaves in compression and anatomical preservation that enable a detailed interpretation of the physiology and ecology of these plants.

    Pivotal results. Our results indicate that the Petriellales were diminutive, evergreen, shade-adapted perennial shrubs that colonized the understory of the deciduous forest biome of polar Gondwana. This life form is very unlike that of any other known seed-plant group of that time. By contrast, it fits remarkably well into the “dark and disturbed” niche that some authors considered to have sheltered the rise of the flowering plants some 100 Myr later.

    Conclusions. The hitherto enigmatic Petriellales are now among the most comprehensively reconstructed groups of extinct seed plants and emerge as promising candidates for elucidating the mysterious origin of the angiosperms.

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  • 21.
    Bomfleur, Benjamin
    et al.
    Naturhistoriska riksmuseet, Enheten för paleobiologi.
    Grimm, Guido
    Naturhistoriska riksmuseet, Enheten för paleobiologi.
    McLoughlin, Stephen
    Naturhistoriska riksmuseet, Enheten för paleobiologi.
    Osmunda pulchella sp. nov. from the Jurassic of Sweden--reconciling molecular and fossil evidence in the phylogeny of modern royal ferns (Osmundaceae)2015Inngår i: BMC Evolutionary Biology, E-ISSN 1471-2148, Vol. 15, nr 126, s. 1-25Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Background: The classification of royal ferns (Osmundaceae) has long remained controversial. Recent molecular phylogenies indicate that Osmunda is paraphyletic and needs to be separated into Osmundastrum and Osmunda s.str. Here, however, we describe an exquisitely preserved Jurassic Osmunda rhizome (O. pulchella sp. nov.) that combines diagnostic features of both Osmundastrum and Osmunda, calling molecular evidence for paraphyly into question. We assembled a new morphological matrix based on rhizome anatomy, and used network analyses to establish phylogenetic relationships between fossil and extant members of modern Osmundaceae. We re-analysed the original molecular data to evaluate root-placement support. Finally, we integrated morphological and molecular data-sets using the evolutionary placement algorithm.

    Results: Osmunda pulchella and five additional Jurassic rhizome species show anatomical character suites intermediate between Osmundastrum and Osmunda. Molecular evidence for paraphyly is ambiguous: a previously unrecognized signal from spacer sequences favours an alternative root placement that would resolve Osmunda s.l. as monophyletic. Our evolutionary placement analysis identifies fossil species as probable ancestral members of modern genera and subgenera, which accords with recent evidence from Bayesian dating.

    Conclusions: Osmunda pulchella is likely a precursor of the Osmundastrum lineage. The recently proposed root placement in Osmundaceae—based solely on molecular data—stems from possibly misinformative outgroup signals in rbcL and atpA genes. We conclude that the seemingly conflicting evidence from morphological, anatomical, molecular, and palaeontological data can instead be elegantly reconciled under the assumption that Osmunda is indeed monophyletic.

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  • 22.
    Bomfleur, Benjamin
    et al.
    Naturhistoriska riksmuseet, Enheten för paleobiologi. Westfälische Wilhelms-Universität Münster.
    Grimm, Guido
    Department fu¨r Pala¨ontologie, Universita¨t Wien, Wien, Austria.
    McLoughlin, Stephen
    Naturhistoriska riksmuseet, Enheten för paleobiologi.
    The fossil Osmundales (Royal Ferns)—a phylogenetic network analysis, revised taxonomy, and evolutionary classification of anatomically preserved trunks and rhizomes2017Inngår i: PeerJ, E-ISSN 2167-8359, Vol. 5, artikkel-id e3433Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The Osmundales (Royal Fern order) originated in the late Paleozoic and is the most ancient surviving lineage of leptosporangiate ferns. In contrast to its low diversity today (less than 20 species in six genera), it has the richest fossil record of any extant group of ferns. The structurally preserved trunks and rhizomes alone are referable to more than 100 fossil species that are classified in up to 20 genera, four subfamilies, and two families. This diverse fossil record constitutes an exceptional source of information on the evolutionary history of the group from the Permian to the present. However, inconsistent terminology, varying formats of description, and the general lack of a uniform taxonomic concept renders this wealth of information poorly accessible. To this end, we provide a comprehensive review of the diversity of structural features of osmundalean axes under a standardized, descriptive terminology. A novel morphological character matrix with 45 anatomical characters scored for 15 extant species and for 114 fossil operational units (species or specimens) is analysed using networks in order to establish systematic relationships among fossil and extant Osmundales rooted in axis anatomy. The results lead us to propose an evolutionary classification for fossil Osmundales and a revised, standardized taxonomy for all taxa down to the rank of (sub)genus. We introduce several nomenclatural novelties: (1) a new subfamily Itopsidemoideae (Guaireaceae) is established to contain Itopsidema, Donwelliacaulis, and Tiania; (2) the thamnopteroid genera Zalesskya, Iegosigopteris, and Petcheropteris are all considered synonymous with Thamnopteris; (3) 12 species of Millerocaulis and Ashicaulis are assigned to modern genera (tribe Osmundeae); (4) the hitherto enigmatic Aurealcaulis is identified as an extinct subgenus of Plenasium; and (5) the poorly known Osmundites tuhajkulensis is assigned to Millerocaulis. In addition, we consider Millerocaulis stipabonettiorum a possible member of Palaeosmunda and Millerocaulis estipularis as probably constituting the earliest representative of the (Todea-)Leptopteris lineage (subtribe Todeinae) of modern Osmundoideae.

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  • 23.
    Bomfleur, Benjamin
    et al.
    Naturhistoriska riksmuseet, Enheten för paleobiologi.
    Klymiuk, Ashley
    Taylor, Edith
    Taylor, Thomas
    Gulbranson, Erik
    Isbell, John
    Diverse bryophyte mesofossils from the Triassic of Antarctica2014Inngår i: Lethaia: an international journal of palaeontology and stratigraphy, ISSN 0024-1164, E-ISSN 1502-3931, Vol. 47, nr 1, s. 120-132Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Compared with the fossil record of vascular plants, bryophyte fossils are rare; this circumstance is probably related to a lower preservation potential compared with that of vascular plants. We searched for bryophyte remains in extensive collections of plant-fossil assemblages from the Triassic of Antarctica and identified three assemblages with surprisingly well-preserved bryophyte fossils. Although most bryophyte remains are too fragmented to conclusively place them in a detailed systematic context, they exhibit features sufficient to suggest the presence of at least four types of leafy bryophytes and two orders of thallose liverworts (Pallaviciniales and Metzgeriales) in the high-latitude Triassic ecosystems of Antarctica. The leafy bryophytes exhibit combinations of morphological features (e.g. keeled and entire-margined, ecostate leaves with elongated cells) that today occur in only a few small, systematically isolated groups, but were common among Palaeozoic and especially Mesozoic bryophytes. The diverse morphologies of the bryophyte fossils add further support to previous hypotheses that during warmer periods in the Earth’s history, bryophyte vegetation may have been particularly rich and diverse in high-latitude regions. Through analysis of the sedimentology and taphonomy of these assemblages, we identify a combination of key factors that may explain the preservation of bryophyte fossils in these deposits: (1) punctuated, high-energetic sedimentary events causing traumatic removal and incorporation of bryophytes into sediment-laden flood waters; (2) limited transport distance, and short period of suspension, followed by rapid settling and burial as a result of a rapidly decelerating flow discharging into a floodplain environment; and (3) early-diagenetic cementation with iron hydroxides in locally anoxic zones of the organic-rich, muddy substrate.

  • 24.
    Bomfleur, Benjamin
    et al.
    Institute for Geology and Palaeontology, Westfälische Wilhelms-Universität Münster.
    Mörs, Thomas
    Naturhistoriska riksmuseet, Enheten för paleobiologi.
    Unverfärth, Jan
    Institute for Geology and Palaeontology, Westfälische Wilhelms-Universität Münster.
    Feng, Liu
    State Key Laboratory of Palaeobiology and Stratigraphy, Nanjing Institute of Geology and Palaeontology.
    Läufer, Andreas
    Federal Institute for Geosciences and Natural Resources (BGR), Germany.
    Castillo, Paula
    Institute for Geology and Palaeontology, Westfälische Wilhelms-Universität Münster.
    Oh, Changhwan
    Department of Earth Sciences Education, Chungbuk National University, Republic of Korea.
    Park, Tae-Yoon, S.
    Division of Polar Earth-System Sciences, Korea Polar Research Institute, Republic of Korea.
    Woo, Jusun
    School of Earth and Environmental Sciences, Seoul National University, Republic of Korea.
    Crispini, Laura
    DISTAV, University of Genova.
    Uncharted Permian to Jurassic continental deposits in the far north of Victoria Land, East Antarctica2020Inngår i: Journal of the Geological Society, ISSN 0016-7649, E-ISSN 2041-479X, Vol. 178, artikkel-id jgs2020-062Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The remote lower reaches of the Rennick Glacier in the far north of Victoria Land hold some of the least-explored outcrop areas of the Transantarctic basin system. Following recent international field-work efforts in the Helliwell Hills, we here provide a comprehensive emendation to the regional stratigraphy. Results of geological and palaeontological reconnaissance and of petrographic, geochemical and palynostratigraphic analyses reveal a stack of three previously unknown sedimentary units in the study area: the Lower Triassic Van der Hoeven Formation (new unit, 115+ m thick) consists mainly of quartzose sandstone and non-carbonaceous mudstone rich in continental trace fossils. The Middle to Upper Triassic Helliwell Formation (new unit, 235 m thick) consists of coal-bearing overbank deposits and volcaniclastic sandstone and yielded typical plant fossils of the Gondwanan Dicroidium flora together with plant-bearing silicified peat. The succession is capped by c. 14 m of the sandstone-dominated Section Peak Formation (uppermost Triassic–Lower Jurassic). Our results enable more detailed correlation of the Palaeozoic–Mesozoic successions throughout East Antarctica and into Tasmania. Of particular interest is one section that spans the end-Permian mass extinction interval, which promises to allow detailed reconstructions of high-latitude vegetation dynamics across this critical interval in Earth history.

  • 25.
    Bomfleur, Benjamin
    et al.
    Naturhistoriska riksmuseet, Enheten för paleobiologi.
    Schöner, Robert
    John, Nadine
    Schneider, Jörg
    Elsner, Martin
    Viereck-Goette, Lothar
    Kerp, Hans
    New Palaeozoic deposits of the Victoria Group in the Eisenhower Range, northern Victoria Land, Antarctica2014Inngår i: Antarctic Science, ISSN 0954-1020, E-ISSN 1365-2079, Vol. 26, nr 3, s. 277-278Artikkel i tidsskrift (Fagfellevurdert)
  • 26.
    Bomfleur, Benjamin
    et al.
    Naturhistoriska riksmuseet, Enheten för paleobiologi.
    Schöner, Robert
    Schneider, Jörg
    Viereck, Lothar
    Kerp, Hans
    McKellar, John
    From the Transantarctic Basin to the Ferrar Large Igneous Province: New palynostratigraphic age constraints for Triassic-Jurassic sedimentation and magmatism in East Antarctica2014Inngår i: Review of Palaeobotany and Palynology, ISSN 0034-6667, E-ISSN 1879-0615, Vol. 207, s. 18-37Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    We present new palynological data from the Transantarctic Mountains that clarify the timing of sedimentary and magmatic processes in the transition from continental deposition of the Beacon Supergroup to emplacement of the Ferrar Large Igneous Province. Samples were collected from twenty-three Triassic and Jurassic sections in the southern area of north Victoria Land (NVL), East Antarctica. Recovered palynomorph assemblages are correlated with the widely used, although informal palynostratigraphic framework established for eastern Australia by Price. The associated Late Triassic–earliest Jurassic zone, APT5, is modified here with a proposed new subdivision: Lower APT5 (“APT5L”; middle–late Norian), Middle APT5 (“APT5M”; Rhaetian), and Upper APT5 (“APT5U”;Hettangian–earliest Sinemurian). We further propose a modification unifying the relevant formal eastern Australian and New Zealand palynostratigraphic zones, with a new Polycingulatisporites crenulatus Association Zone (new zonal status) that includes the P. crenulatus Association Subzone (new subzone; equivalent toAPT5L) and the following Foveosporites moretonensis Association Subzone (new subzonal status; equivalent to APT5M). Our palynostratigraphic dating of the NVL assemblages demonstrates that the onset of sedimentation was diachronous in this part of the Transantarctic Basin, ranging from at least the Rhaetian to, in places, early Sinemurian. By lack of evidence for rocks containing APT5U assemblages and by analogy with the few coeval sections in Australia, we infer that the Hettangian interval in NVL is probably consumed by unconformity. Depositionof ashes from distal silicic volcanism commenced in the early Sinemurian and reached a peak phase beginning in middle Pliensbachian (ca 187Ma), coinciding with the first major magmatic interval of the silicic Chon Aike Province in Patagonia and West Antarctica. Two major episodes of phreatomagmatic activity, driven by shallow-level sill intrusion into sandstone aquifers, occurred during the middle Pliensbachian and during the late Pliensbachian–early Toarcian. The latter episode was closely followed by the first pillow extrusion and local lava effusion. Contrary to some previous studies, we further conclude that all available palynological evidence is compatible with a short-lived emplacement of the plateau-forming Kirkpatrick Basalt at around 180 Ma during the early Toarcian.

  • 27.
    Bosi, Ferdinando
    University of Rome "La Sapienza".
    Balik-Zunic, Tonci
    Natural History Museum of Denmark.
    Thermal stability of extended clusters in dravite: a combined EMP, SREF and FTIR study.2016Inngår i: Physics and chemistry of minerals, ISSN 0342-1791, E-ISSN 1432-2021, Vol. 43, s. 395-407Artikkel i tidsskrift (Fagfellevurdert)
  • 28.
    Bouchal, Johannes M.
    et al.
    Naturhistoriska riksmuseet, Enheten för paleobiologi.
    Denk, Thomas
    Naturhistoriska riksmuseet, Enheten för paleobiologi.
    Low taxonomic resolution of papillate Cupressaceae pollen (former Taxodiaceae) impairs their applicability for palaeo-habitat reconstruction2020Inngår i: Grana, ISSN 0017-3134, E-ISSN 1651-2049, Vol. 59, nr 1, s. 71-93, artikkel-id https://doi.org/10.1080/00173134.2019.1701704Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The former family Taxodiaceae is currently treated as nine genera in five subfamilies of the family Cupressaceae. Pollen ofthe ‘taxodiaceous’ Cupressaceae typically has a papilla in the leptoma area and is common in Cenozoic strata because someof its genera were key elements in lignite forming swamp forests. Dispersed fossil pollen of this group are often assigned toparticular genera and, based on the modern ecologies of these taxa, to particular palaeoenvironments. In this study, weinvestigated pollen of all nine genera of the former Taxodiaceae using light and scanning electron microscopy to evaluatewhether pollen morphology can be used to discriminate modern genera of this paraphyletic group. We found few genus- orsubfamily-diagnostic characters among members of taxodiaceous Cupressaceae. Features such as orbiculae and pollen andleptoma size cannot be used to discriminate subfamilies. However, three basal subfamilies share short papillae, whereas intwo more derived clades (Sequoioideae and Taxodioideae) papillae are markedly longer. In the generally non-papillate coreCupressaceae, the leptoma (aperture) area may or may not possess a distinct circular thinning as also found in the basalgrade of taxodiaceous Cupressaceae. Our results show that it is difficult if not impossible to distinguish genera of theecologically distinct Taxodioideae and Sequoioideae based on pollen morphology. In view of a much wider ecologicalamplitude of many taxodiaceous Cupressaceae during large parts of the Cenozoic, we conclude that it is not recommendableto infer particular palaeoenvironments on the basis of dispersed taxodiaceous pollen grains alone.

  • 29.
    Bouchal, Johannes M.
    et al.
    Naturhistoriska riksmuseet, Enheten för paleobiologi.
    Güner, Tuncay H.
    Naturhistoriska riksmuseet, Enheten för paleobiologi. Faculty of Forestry, Department of Forest Botany, Istanbul University Cerrahpa¸sa, 34473 Bahçeköy, Istanbul, Turkey.
    Velitzelos, Dimitrios
    National and Kapodistrian University of Athens.
    Velitzelos, Evangelos
    National and Kapodistrian University of Athens.
    Denk, Thomas
    Naturhistoriska riksmuseet, Enheten för paleobiologi.
    Messinian vegetation and climate of the intermontane Florina–Ptolemais–Servia Basin, NW Greece inferred from palaeobotanical data: how well do plant fossils reflect past environments?2020Inngår i: Royal Society Open Science, E-ISSN 2054-5703, Vol. 7, s. 1-30, artikkel-id 192067Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The late Miocene is marked by pronounced environmentalchanges and the appearance of strong temperature andprecipitation seasonality. Although environmental heterogeneityis to be expected during this time, it is challenging to reconstructpalaeoenvironments using plant fossils. We investigated leavesand dispersed spores/pollen from 6.4 to 6 Ma strata inthe intermontane Florina–Ptolemais–Servia Basin (FPS) ofnorthwestern Greece. To assess how well plant fossils reflectthe actual vegetation of the FPS, we assigned fossil taxa tobiomes providing a measure for environmental heterogeneity.Additionally, the palynological assemblage was compared withpollen spectra from modern lake sediments to assess biases inspore/pollen representation in the pollen record. We found aclose match of the Vegora assemblage with modern Fagus–Abiesforests of Turkey. Using taxonomic affinities of leaf fossils, wefurther established close similarities of the Vegora assemblage with modern laurophyllous oak forests of Afghanistan. Finally, using information from sedimentaryenvironment and taphonomy, we distinguished local and distantly growing vegetation types.We thensubjected the plant assemblage of Vegora to different methods of climate reconstruction and discussedtheir potentials and limitations. Leaf and spore/pollen records allow accurate reconstructions ofpalaeoenvironments in the FPS, whereas extra-regional vegetation from coastal lowlands isprobably not captured.

    Fulltekst (pdf)
    Bouchal et al 2020 Vegora
  • 30.
    Bralower, T
    et al.
    Pennsylvania State University.
    Cosmidis, J
    Pennsylvania State University.
    Fantle, M.S.
    Pennsylvania State University.
    Lowery, C.M.
    University of Texas at Austin.
    Passey, B.H.
    University of Michigan.
    Gulick, S.P.S.
    University of Texas at Austin.
    Morgan, J.V.
    Imperial College London.
    Vajda, Vivi
    Naturhistoriska riksmuseet, Enheten för paleobiologi. Department of Geology, Lund University, Sweden.
    Whalen, M.T.
    University of Alaska Fairbanks.
    Wittmann, A.
    Arizona State University,.
    Artemieva, N.
    Planetary Science Institute, Tucson.
    Farley, K.
    California Institute of Technology.
    Goderis, S.
    Vrije Universiteit Brussel.
    Hajek, E.
    Pennsylvania State University.
    Heaney, P.J.
    Pennsylvania State University.
    Kring, D.A.
    Lunar and Planetary Institute, Houston.
    Lyons, S.L.
    Pennsylvania State University.
    Rasmussen, C.
    University of Texas at Austin.
    Sibert, E.
    Yale University.
    Rodríguez Tovar, F.J.
    Universidad de Granada.
    Turner-Walker, G.
    National Yunlin University of Science and Technology.
    Zachos, J.C.
    University of California, Santa Cruz.
    Carte, J.
    Pennsylvania State University.
    Chen, S.A.
    Pennsylvania State University.
    Cockell, C.
    University of Edinburgh.
    Coolen, M.
    Curtin University.
    Freeman, K.H.
    Pennsylvania State University.
    Garber, J.
    Pennsylvania State University.
    Gonzalez, M.
    Pennsylvania State University.
    Gray, J.L.
    Pennsylvania State University.
    Grice, K.
    Curtin University.
    Jones, H.L.
    Pennsylvania State University.
    Schaefer, B.
    Curtin University.
    Smit, J.
    VU Universiteit Amsterdam.
    Tikoo, S.M.
    Stanford University.
    The Habitat of the Nascent Chicxulub Crater2020Inngår i: AGU Advances, Vol. 1, artikkel-id e2020AV000208Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    An expanded sedimentary section provides an opportunity to elucidate conditions in the nascent Chicxulub crater during the hours to millennia after the Cretaceous‐Paleogene (K‐Pg) boundary impact. The sediments were deposited by tsunami followed by seiche waves as energy in the crater declined, culminating in a thin hemipelagic marlstone unit that contains atmospheric fallout. Seiche deposits are predominantly composed of calcite formed by decarbonation of the target limestone during impact followed by carbonation in the water column. Temperatures recorded by clumped isotopes of these carbonates are in excess of 70°C, with heat likely derived from the central impact melt pool. Yet, despite the turbidity and heat, waters within the nascent crater basin soon became a viable habitat for a remarkably diverse cross section of the food chain. The earliest seiche layers deposited with days or weeks of the impact contain earliest Danian nannoplankton and dinocyst survivors. The hemipelagic marlstone representing the subsequent years to a few millennia contains a nearly monogeneric calcareous dinoflagellate resting cyst assemblage suggesting deteriorating environmental conditions, with one interpretation involving low light levels in the impact aftermath. At the same horizon, microbial fossils indicate a thriving bacterial community and unique phosphatic fossils including appendages of pelagic crustaceans, coprolites andbacteria‐tunneled fish bone, suggesting that this rapid recovery of the base of the food chain may have supported the survival of larger, higher trophic‐level organisms. The extraordinarily diverse fossil assemblage indicates that the crater was a unique habitat in the immediate impact aftermath, possibly as aresult of heat and nutrients supplied by hydrothermal activity.

    Fulltekst (pdf)
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  • 31.
    Bralower, Timothy
    et al.
    Pennsylvania State University.
    Cosmidis, Julie
    Pennsylvania State University.
    Heaney, Peter
    Pennsylvania State University.
    Kump, Lee
    Pennsylvania State University.
    Morgan, Joanna
    Imperial College London.
    Haroer, Dustin
    University of Kansas.
    Lyons, Shelby
    Pennsylvania State University.
    Freeman, Katherine
    Pennsylvania State University.
    Grice, Kliti
    Curtin University.
    Wendler, Jens
    Friedrich-Schiller-University Jena.
    Zachos, James
    University of California Santa Cruz.
    Artemieva, Natalia
    Planetary Science Institute, Tucson.
    Chen, Si Athena
    Pennsylvania State University.
    Gulick, Sean
    University of Texas.
    House, Christopher
    Pennsylvania State University.
    Jones, Heather
    Pennsylvania State University.
    Lowery, Christopher
    University of Texas at Austin.
    Nims, Christine
    Pennsylvania State University.
    Schaefer, Bettina
    Curtin University.
    Thomas, Ellen
    Yale University.
    Vajda, Vivi
    Naturhistoriska riksmuseet, Enheten för paleobiologi. Department of Geology, Lund University, Sweden.
    Origin of a global carbonate layer deposited in the aftermath of the Cretaceous-Paleogene boundary impact2020Inngår i: Earth and Planetary Science Letters, ISSN 0012-821X, E-ISSN 1385-013X, Vol. 548, artikkel-id 116476Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Microcrystalline calcite (micrite) dominates the sedimentary record of the aftermath of the Cretaceous–Paleogene (K–Pg) impact at 31 sites globally, with records ranging from the deep ocean to the Chicxulub impact crater, over intervals ranging from a few centimeters to more than seventeen meters. This micrite-rich layer provides important information about the chemistry and biology of the oceans after the impact. Detailed high-resolution scanning electron microscopy demonstrates that the layer contains abundant calcite crystals in the micron size range with a variety of forms. Crystals are often constructed of delicate, oriented agglomerates of sub-micrometer mesocrystals indicative of rapid precipitation. We compare the form of crystals with natural and experimental calcite to shed light on their origin. Close to the crater, a significant part of the micrite may derive from the initial backreaction of CaO vaporized during impact. In more distal sites, simple interlocking rhombohedral crystals resemble calcite precipitated from solution. Globally, we found unique calcite crystals associated with fossilized extracellular materials that strikingly resemble calcite precipitated by various types of bacteria in natural and laboratory settings. The micrite-rich layer contains abundant bacterial and eukaryotic algal biomarkers and most likely represents global microbial blooms initiated within millennia of the K–Pg mass extinction. Cyanobacteria and non-haptophyte microalgae likely proliferated as dominant primary producers in cold immediate post-impact environments. As surface-water saturation state rose over the following millennia due to the loss of eukaryotic carbonate producers and continuing river input of alkalinity, “whitings” induced by cyanobacteria replaced calcareous nannoplankton as major carbonate producers. We postulate that the blooms grew in supersaturated surface waters as evidenced by crystals that resemble calcite precipitates from solution. The microbial biomass may have served as a food source enabling survival of a portion of the marine biota, ultimately including life on the deep seafloor. Although the dominance of cyanobacterial and algal photosynthesis would have weakened the biological pump, it still would have removed sufficient nutrients from surface waters thus conditioning the ocean for the recovery of biota at highertrophic levels.

    Fulltekst (pdf)
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  • 32. Butler, Aodhán
    et al.
    Cunningham, John
    Naturhistoriska riksmuseet, Enheten för paleobiologi.
    Budd, Graham
    Donoghue, Philip
    Experimental taphonomy of Artemia reveals the role of endogenous microbes in mediating decay and fossilization2015Inngår i: Proceedings of the Royal Society of London. Biological Sciences, ISSN 0962-8452, E-ISSN 1471-2954, Vol. 282, s. 20150476-Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Exceptionally preserved fossils provide major insights into the evolutionary

    history of life. Microbial activity is thought to play a pivotal role in both the

    decay of organisms and the preservation of soft tissue in the fossil record,

    though this has been the subject of very little experimental investigation.

    To remedy this, we undertook an experimental study of the decay of the

    brine shrimp Artemia, examining the roles of autolysis, microbial activity,

    oxygen diffusion and reducing conditions. Our findings indicate that

    endogenous gut bacteria are the main factor controlling decay. Following

    gut wall rupture, but prior to cuticle failure, gut-derived microbes spread

    into the body cavity, consuming tissues and forming biofilms capable of

    mediating authigenic mineralization, that pseudomorph tissues and structures

    such as limbs and the haemocoel. These observations explain patterns

    observed in exceptionally preserved fossil arthropods. For example, guts

    are preserved relatively frequently, while preservation of other internal anatomy

    is rare. They also suggest that gut-derived microbes play a key role in the

    preservation of internal anatomy and that differential preservation between

    exceptional deposits might be because of factors that control autolysis and

    microbial activity. The findings also suggest that the evolution of a through

    gut and its bacterial microflora increased the potential for exceptional fossil

    preservation in bilaterians, providing one explanation for the extreme rarity

    of internal preservation in those animals that lack a through gut.

    Fulltekst (pdf)
    fulltext
  • 33.
    Campeau, Aydrey
    et al.
    Uppsala University.
    Soerensen, Anne L.
    Naturhistoriska riksmuseet, Enheten för miljöforskning och övervakning.
    Martma, T
    Tallinn University of Technology.
    Åkeblom, Staffan
    Statistic Sweden.
    Zdanowicz, Christian
    Uppsala University.
    Controls on the 14C Content of Dissolved and Particulate Organic Carbon Mobilized Across the Mackenzie River Basin, Canada2020Inngår i: Global Biogeochemical Cycles, ISSN 0886-6236, E-ISSN 1944-9224, Vol. 34, nr 12Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The Mackenzie River Basin (MRB) delivers large quantities of organic carbon (OC) into the Arctic Ocean, with significant implications for the global C budgets and ocean biogeochemistry. The amount and properties of OC in the Mackenzie River's delta have been well monitored in the last decade, but the spatial variability in OC sources transported by its different tributaries is still unclear. Here we present new data on the radiocarbon (14C) content of dissolved and particulate OC (Δ14C‐DOC and Δ14C‐POC) across the mainstem and major tributaries of the MRB, comprising 19 different locations, to identify factors controlling spatial patterns in riverine OC sources. The Δ14C‐DOC and Δ14C‐POC varied across a large range, from −179.9‰ to 62.9‰, and −728.8‰ to −9.0‰, respectively. Our data reveal a positive spatial coupling between the Δ14C of DOC and POC across the MRB, whereby the most 14C‐depleted waters were issued from the mountainous west bank of the MRB. This 14C‐depleted DOC and POC likely originates from a combination of petrogenic sources, connected with the presence of kerogens in the bedrock, and biogenic sources, mobilized by thawing permafrost. Our analysis also reveals intriguing relationships between Δ14C of DOC and POC with turbidity, water stable isotope ratio and catchment elevation, indicating that hydrology and geomorphology are key to understanding riverine OC sources in this landscape. A closer examination of the specific mechanisms giving rise to these relationships is recommended. For now, this study provides a road map of the key OC sources in this rapidly changing river basin.

    Fulltekst (pdf)
    Campeau et al 2020
  • 34.
    Cardoni, Simone
    et al.
    Department of Agricultural and Forestry Science (DAFNE) Università degli studi della Tuscia Viterbo 01100 Italy.
    Piredda, Roberta
    Department of Veterinary Medicine University of Bari ‘Aldo Moro’ Valenzano 70010 Italy.
    Denk, Thomas
    Naturhistoriska riksmuseet, Enheten för paleobiologi.
    Grimm, Guido W.
    Unaffiliated, Orléans France.
    Papageorgiou, Aristotelis C.
    Department of Molecular Biology and Genetics Democritus University of Thrace Alexandroupolis Greece.
    Schulze, Ernst‐Detlef
    Max‐Planck Institute for Biogeochemistry Jena 07701 Germany.
    Scoppola, Anna
    Department of Agricultural and Forestry Science (DAFNE) Università degli studi della Tuscia Viterbo 01100 Italy.
    Salehi Shanjani, Parvin
    Natural Resources Gene Bank, Research Institute of Forests and Rangelands Agricultural Research, Education and Extension Organization Tehran Iran.
    Suyama, Yoshihisa
    Graduate School of Agricultural Science Tohoku University Osaki Miyagi 989‐6711 Japan.
    Tomaru, Nobuhiro
    Graduate School of Bioagricultural Sciences Nagoya University Nagoya Aichi 464‐8601 Japan.
    Worth, James R. P.
    Ecological Genetics Laboratory Forestry and Forest Products Research Institute (FFPRI) Tsukuba Ibaraki 305‐8687 Japan.
    Cosimo Simeone, Marco
    Department of Agricultural and Forestry Science (DAFNE) Università degli studi della Tuscia Viterbo 01100 Italy.
    5S‐IGS rDNA in wind‐pollinated trees ( Fagus L.) encapsulates 55 million years of reticulate evolution and hybrid origins of modern species2021Inngår i: The Plant Journal, ISSN 0960-7412, E-ISSN 1365-313X, Vol. 109, nr 4, s. 909-926Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Standard models of plant speciation assume strictly dichotomous genealogies in which a species, theancestor, is replaced by two offspring species. The reality in wind-pollinated trees with long evolutionaryhistories is more complex: species evolve from other species through isolation when genetic drift exceeds gene flow; lineage mixing can give rise to new species (hybrid taxa such as nothospecies and allopolyploids). The multi-copy, potentially multi-locus 5S rDNA is one of few gene regions conserving signal from dichotomous and reticulate evolutionary processes down to the level of intra-genomic recombination. Therefore, it can provide unique insights into the dynamic speciation processes of lineages that diversified tens of millions of years ago. Here, we provide the first high-throughput sequencing (HTS) of the 5S intergenic spacers (5S-IGS) for a lineage of wind-pollinated subtropical to temperate trees, the Fagus crenata – F.sylvatica s.l. lineage, and its distant relative F. japonica. The observed 4963 unique 5S-IGS variants reflect acomplex history of hybrid origins, lineage sorting, mixing via secondary gene flow, and intra-genomic competition between two or more paralogous-homoeologous 5S rDNA lineages. We show that modern species are genetic mosaics and represent a striking case of ongoing reticulate evolution during the past 55 million years.

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  • 35.
    CARPENTER, RAYMOND
    et al.
    University of Tasmania.
    McLoughlin, Stephen
    Naturhistoriska riksmuseet, Enheten för paleobiologi.
    HILL, ROBERT
    University of Adelaide.
    McNAMARA, KENNETH
    University of Cambridge.
    JORDAN, GREGORY
    University of Tasmania.
    EARLY EVIDENCE OF XEROMORPHY IN ANGIOSPERMS: STOMATAL ENCRYPTION IN A NEW EOCENE SPECIES OF BANKSIA (PROTEACEAE) FROM WESTERN AUSTRALIA2014Inngår i: American Journal of Botany, ISSN 0002-9122, E-ISSN 1537-2197, Vol. 101, nr 9, s. 1486-1497Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Premise of the study: Globally, the origins of xeromorphic traits in modern angiosperm lineages are obscure but are thought to be linked to the early Neogene onset of seasonally arid climates. Stomatal encryption is a xeromorphic trait that is prominent in Banksia , an archetypal genus centered in one of the world’s most diverse ecosystems, the ancient infertile landscape of Mediterranean-climate southwestern Australia.

    Methods: We describe Banksia paleocrypta , a sclerophyllous species with encrypted stomata from silcretes of the Walebing and Kojonup regions of southwestern Australia dated as Late Eocene.

    Key results: Banksia paleocrypta shows evidence of foliar xeromorphy ~20 Ma before the widely accepted timing for the onset of aridity in Australia. Species of Banksia subgenus Banksia with very similar leaves are extant in southwestern Australia. The conditions required for silcrete formation infer fl uctuating water tables and climatic seasonality in southwestern Australia in the Eocene, and seasonality is supported by the paucity of angiosperm closed-forest elements among the fossil taxa preserved with B. paleocrypta. However, climates in the region during the Eocene are unlikely to have experienced seasons as hot and dry as present-day summers.

    Conclusions: The presence of B. paleocrypta within the center of diversity of subgenus Banksia in edaphically ancient southwestern Australia is consistent with the continuous presence of this lineage in the region for ≥ 40 Ma, a testament to the success of increasingly xeromorphic traits in Banksia over an interval in which numerous other lineages became extinct.

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  • 36.
    Cavalcante, Larissa Lopes
    et al.
    Naturhistoriska riksmuseet, Enheten för paleobiologi.
    Barbolini, Natasha
    Department of Ecology, Environment and Plant Sciences and Bolin Centre for Climate Research, Stockholm University, SE-106 91 Stockholm, Sweden.
    Bacsik, Zoltán
    Department of Materials and Environmental Chemistry, Stockholm University, SE-106 91 Stockholm, Sweden.
    Vajda, Vivi
    Naturhistoriska riksmuseet, Enheten för paleobiologi.
    Analysis of fossil plant cuticles using vibrational spectroscopy: A new preparation protocol2023Inngår i: Review of Palaeobotany and Palynology, ISSN 0034-6667, E-ISSN 1879-0615, Vol. 316, artikkel-id 104944Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Analyses for organic “fingerprints” on fossilized plant cuticles and pollen hold valuable chemotaxonomic and palaeoclimatic information, and are thus becoming more utilized by palaeobotanists. Plant cuticle and pollen composition are generally analyzed after standard treatments with several chemical reagents for mineral and mesophyll removal. However, the potential alterations on the fossil composition caused by the different cleaning reagents used are still poorly understood. We tested the effects of commonly used palaeobotanical processing methods on the spectra of fossilized cuticles from successions of Late Triassic to Early Jurassic age, including the gymnosperms Lepidopteris, Ginkgoites, Podozamites, Ptilozamites and Pterophyllum astartense. Our study shows that standard chemical processing caused chemical alterations that might lead to erroneous interpretation of the infrared (IR) spectra. The difference in pH caused by HCl induces changes in the proportion between the two bands at ~1720 and 1600 cm 1 (carboxylate and C-C stretch of aromatic compounds) indicating that the band at ~1610 cm 1 at least partially corresponds to carboxylate instead of C-C stretch of aromatic compounds. Interestingly, despite being used in high concentration, HF did not cause changes in the chemical composition of the cuticles. The most alarming changes were caused by the use of Schulze ’s solution, which resulted in the addition of both NO2 and (O)NO2 compounds in the cuticle. Consequently, a new protocol using H2CO3, HF, and H2O2 for preparing fossil plant cuticles aimed for chemical analyses is proposed, which provides an effective substitute to the conventional methods. In particular, a less aggressive and more sustainable alternative to Schulze’s solution is shown to be hydrogen peroxide, which causes only minor alteration of the fossil cuticle ’s chemical composition. Future work should carefully follow protocols, having in mind the impacts of different solutions used to treat leaves and other palaeobotanical material such as palynomorphs with aims to enable the direct comparison of spectra obtained in different studies.

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    Cavalcante et al_2023_Analysis of fossil plant cuticles using vibrational spectroscopy
  • 37. Ceballos, Yasmani
    et al.
    Orihuela, Johanset
    Kiel, Steffen
    Naturhistoriska riksmuseet, Enheten för paleobiologi.
    Corals and mollusks from a Miocene carbonate-rich deposit of Madruga, western Cuba2021Inngår i: Poeyana, ISSN 2410-7492, Vol. 512, s. 1-7Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Here is reported fauna from a Middle Miocene limestone deposit of the Cojímar Formation near the town of Aguacate in the Province of Mayabeque, western Cuba. The fossils are preserved only as internal or external molds, but we identified members of at least eight bivalves and six gastropod families and one solitary coral. The most common taxon is a lucinid bivalve probably belonging to the genus Anodontia, which may likely represent a new taxon. This species in particular, and the fauna and facies in general, suggest that the Aguacate limestone may represent an ancient seagrass meadow environment. The fauna of the Aguacate quarry shows biogeographic relationships mainly to the Miocene of Panama and Florida, but also some links to the subtropical Atlantic coast of North America, and the Miocene of northern Ecuador.

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  • 38.
    Chen, Feiyang
    et al.
    Key Laboratory of Coalbed Methane Resources and Reservoir Formation Process of the Ministry of Education, School of Resources and Geosciences, China University of Mining and Technology, Xuzhou 221116, China; State Key Laboratory of Continental Dynamics, Shaanxi Key Laboratory of Early Life & Environments and Department of Geology, Northwest University, Xi’an 710069, China.
    Topper, Timothy
    Naturhistoriska riksmuseet, Enheten för paleobiologi.
    Skovsted, Christian
    Naturhistoriska riksmuseet, Enheten för paleobiologi.
    Strotz, Luke C.
    State Key Laboratory of Continental Dynamics, Shaanxi Key Laboratory of Early Life & Environments and Department of Geology, Northwest University, Xi’an 710069, China.
    Shen, Jian
    Key Laboratory of Coalbed Methane Resources and Reservoir Formation Process of the Ministry of Education, School of Resources and Geosciences, China University of Mining and Technology, Xuzhou 221116, China.
    Zhang, Zhifei
    State Key Laboratory of Continental Dynamics, Shaanxi Key Laboratory of Early Life & Environments and Department of Geology, Northwest University, Xi’an 710069, China.
    Cambrian ecological complexities: Perspectives from the earliest brachiopod – supported benthic communities in the early Cambrian Guanshan Lagerstätte2022Inngår i: Gondwana Research, ISSN 1342-937X, E-ISSN 1878-0571, Vol. 107, s. 30-41Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The Cambrian radiation is characterized by the emergence of diverse bilaterian animal phyla and theestablishment of complex marine ecosystems. The Guanshan Biota records an unusual ecological transition from trilobite- to brachiopod-dominated communities during Cambrian Stage 4. This community transition is accompanied by direct evidence of in situ biological interactions such as durophagous pre-dation and kleptoparasitism. Here we describe new material from the Guanshan biota, focusing on an association of palaeoscolecidomorphs and brachiopods with parasitic tube worms that occur on micro-bedding planes. The bedding plane assemblages are dominated by the organophosphatic brachiopod Neobolus wulongqingensis encrusted with kleptoparasitic tube-dwelling worms, along with infaunal palaeoscolecidans. Taphonomic and sedimentological evidence indicates that these specimens are com-monly preserved in life position, and thus the association between individuals represent potential biological interactions. This case study reveals that ecosystems during the early Cambrian exhibited a well-developed system of tiering and a complex trophic network, easily distinguished from the simple communities typical of precursor deposits in the Ediacaran. Brachiopods forming extremely dense concentrations on the sea floor are effectively acting as ecosystem engineers, not only to stabilize the soft-substrate seafloor, but also act as an alternative substrate for the oldest empirically demonstrated kleptoparasites.The in situ biological interactions preserved in the Guanshan Biota are critical for filling gaps in ourknowledge of ecosystem complexity in the Cambrian.

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  • 39.
    Chi Fru, Ernest
    et al.
    Department of Geological Sciences, 10691, Stockholm University, Stockholm, Sweden; School of Earth and Ocean Sciences, Cardiff University, Park Place, CF10 3AT Cardiff, UK.
    Kilias, Stephanos
    Department of Economic Geology and Geochemistry, Faculty of Geology and Geoenvironment, National and Kapodistrian University of Athens, Panepistimiopolis, Zographou, 15784, Athens, Greece.
    Ivarsson, Magnus
    Naturhistoriska riksmuseet, Enheten för paleobiologi.
    Rattray, Jayne E.
    Department of Geological Sciences, 10691, Stockholm University, Stockholm, Sweden.
    Gkika, Katerina
    Department of Economic Geology and Geochemistry, Faculty of Geology and Geoenvironment, National and Kapodistrian University of Athens, Panepistimiopolis, Zographou, 15784, Athens, Greece.
    McDonald, Iain
    School of Earth and Ocean Sciences, Cardiff University, Park Place, CF10 3AT Cardiff, UK.
    He, Qian
    School of Chemistry, Cardiff University, Park Place, CF10 3AT Cardiff, UK.
    Broman, Curt
    Department of Geological Sciences, 10691, Stockholm University, Stockholm, Sweden.
    Sedimentary mechanisms of a modern banded iron formation on MIlos Island, Greece2018Inngår i: Solid Earth, ISSN 1869-9510, E-ISSN 1869-9529, Vol. 9, s. 573-598Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    An early Quaternary shallow submarine hydrothermal iron formation (IF) in the Cape Vani sedimentary basin (CVSB) on Milos Island, Greece, displays banded rhythmicity similar to Precambrian banded iron formation (BIF). Field-wide stratigraphic and biogeochemical reconstructions show two temporal and spatially isolated iron deposits in the CVSB with distinct sedimentological character. Petrographic screening suggests the presence of a photoferrotrophic-like microfossil-rich IF (MFIF), accumulated on a basement consisting of andesites in a ∼ 150m wide basin in the SW margin of the basin. A banded nonfossiliferous IF (NFIF) sits on top of the Mn-rich sandstones at the transition to the renowned Mn-rich formation, capping the NFIF unit. Geochemical data relate the origin of the NFIF to periodic submarine volcanism and water column oxidation of released Fe(II) in conditions predominated by anoxia, similar to the MFIF. Raman spectroscopy pairs hematite-rich grains in the NFIF with relics of a carbonaceous material carrying an average δ13Corg signature of ∼ −25‰. A similar δ13Corg signature in the MFIF could not be directly coupled to hematite by mineralogy. The NFIF, which postdates large-scale Mn deposition in the CVSB, is composed primarily of amorphous Si (opal-SiO2 ⋅ nH2O) while crystalline quartz (SiO2) predominates the MFIF. An intricate interaction between tectonic processes, changing redox, biological activity, and abiotic Si precipitation are proposed to have collectively formed the unmetamorphosed BIF-type deposits in a shallow submarine volcanic center. Despite the differences in Precambrian ocean–atmosphere chemistry and the present geologic time, these formation mechanisms coincide with those believed to have formed Algoma-type BIFs proximal to active seafloor volcanic centers.

  • 40. Chiappe, Luis M
    et al.
    Lamb, James P
    Ericson, Per G P
    Naturhistoriska riksmuseet, Forskningsavdelningen centralt.
    New enantiornithine bird from the marine Upper Cretaceous of Alabama2002Inngår i: Journal of Vertebrate Paleontology, ISSN 0272-4634, E-ISSN 1937-2809, Vol. 22, nr 1, s. 170-174Artikkel i tidsskrift (Fagfellevurdert)
  • 41.
    Choo, Thereis
    et al.
    School of Integrative Plant Science, Cornell University, Ithaca,.
    Escapa, Ignacio
    CONICET, Museo Paleontológico Egidio Feruglio, Trelew U9100GYO, Chubut, Argentina.
    Benjamin, Bomfleur
    Naturhistoriska riksmuseet, Enheten för paleobiologi.
    Monotypic colonies of Clathropteris meniscioides (Dipteridaceae) from the Early Jurassic of central Patagonia, Argentina: implications for taxonomy and palaeoecology2016Inngår i: Palaeontographica. Abteilung B, Palaophytologie, ISSN 0375-0299, Vol. 294, s. 85-109Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    A collection of over 130 specimens of the fossil dipterid fern Clathropteris meniscioides (Brongn. 1825) Brongn. 1828 from in-situ colonies in the Lower Jurassic of Chubut, Argentina, provides evidence for population-level morphological variation within the species and palaeoecology of the site. Characters such as angle of insertion of secondary veins, tertiary vein arrangement and tooth depth were observed to vary between specimens, and the total range of variation captured by this population was found to overlap and intergrade with the descriptions of several previously identified Clathropteris species. This suggests that species delimitations based on minor differences in such characters should be regarded with skepticism, and that the current number of species ascribed to this genus may be artificially inflated. Abundant C. meniscioides fossils at different development stages buried together in a single, thick bed of sheet-flood deposits provide evidence for the species having formed large, pure colonies in open, disturbed floodplain areas. The characteristic and extremely high leaf-vein densities would have allowed for greater carbon assimilation and rapid growth rates. Altogether, this suggests that the species was a fast-growing pioneer species of floodplains, a prominent part of the Early Jurassic vegetation in Gondwana, and a likely food source for large herbivorous dinosaurs common at that time.

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  • 42.
    Chris, Mays
    et al.
    Naturhistoriska riksmuseet, Enheten för paleobiologi. Monash University.
    Bevitt, Joseph
    Australian Nuclear Science and Technology Organisation, Research Office, Lucas Heights, Australia.
    Stilwell, Jeffrey
    School of Earth, Atmosphere and Environment, Monash University, Clayton, Victoria, Australia.
    Pushing the limits of neutron tomography in palaeontology: Three-dimensional modelling of in situ resin within fossil plants2017Inngår i: Palaeontologia Electronica, ISSN 1935-3952, E-ISSN 1094-8074, Vol. 20, nr 3, s. 1-12, artikkel-id 20.3.57AArtikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Computed tomography is an increasingly popular technique for the non-destructivestudy of fossils. Whilst the science of X-ray computed tomography (CT) has greatlymatured since its first fossil applications in the early 1980s, the applications and limitationsof neutron tomography (NT) remain relatively unexplored in palaeontology. Thesehighest resolution neutron tomographic scans in palaeontology to date were conductedon a specimen of Austrosequoia novae-zeelandiae (Ettingshausen) Mays and Cantrillrecovered from mid-Cretaceous (Cenomanian; ~100–94 Ma) strata of the ChathamIslands, eastern Zealandia. Previously, the species has been identified with in situ fossilresin (amber); the new neutron tomographic analyses demonstrated an anomalouslyhigh neutron attenuation signal for fossil resin. The resulting data provided astrong contrast between, and distinct three-dimensional representations of the: 1) fossilresin; 2) coalified plant matter; and 3) sedimentary matrix. These data facilitated ananatomical model of endogenous resin bodies within the cone axis and bract-scalecomplexes. The types and distributions of resin bodies support a close alliance withSequoia Endlicher (Cupressaceae), a group of conifers whose extant members areonly found in the Northern Hemisphere. This study demonstrates the feasibility of NTas a means to differentiate chemically distinct organic compounds within fossils.Herein, we make specific recommendations regarding: 1) the suitability of fossil preservationstyles for NT; 2) the conservation of organic specimens with hydrogenous consolidantsand adhesives; and 3) the application of emerging methods (e.g., neutronphase contrast) for further improvements when imaging fine-detailed anatomical structures.These findings demonstrate that we are still far from reaching the conceptuallimits of NT as a means of virtually extracting fossils, or imaging their internal anatomyeven when embedded within a rock matrix.

    Fulltekst (pdf)
    Mays et al (2017) - Neutron tomography - methods - in situ resin
  • 43.
    Claybourn, Thomas M.
    Uppsala University.
    Skovsted, Christian
    Naturhistoriska riksmuseet, Enheten för paleobiologi.
    Topper, Timothy
    Naturhistoriska riksmuseet, Enheten för paleobiologi.
    Holmer, Lars, E.
    Uppsala University.
    Brock, Glenn, A.
    Macquarie University.
    Mollusks from the upper Shackleton Limestone (Cambrian Series 2), Central Transantarctic Mountains, East Antarctica2019Inngår i: Journal of Paleontology, ISSN 0022-3360, E-ISSN 1937-2337, Vol. 93, nr 3, s. 437-459Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    An assemblage of Cambrian Series 2, Stages 3–4, conchiferan mollusks from the Shackleton Limestone, Transantarctic Mountains, East Antarctica, is formally described and illustrated. The fauna includes one bivalve, one macromollusk, and 10 micromollusks, including the first description of the species Xinjispira simplex Zhou and Xiao, 1984 outside North China. The new fauna shows some similarity to previously described micromollusks from lower Cambrian glacial erratics from the Antarctic Peninsula. The fauna, mainly composed of steinkerns, is relatively low diversity, but the presence of diagnostic taxa, including helcionelloid Davidonia rostrata (Zhou and Xiao, 1984), bivalve Pojetaia runnegari Jell, 1980, cambroclavid Cambroclavus absonus Conway Morris in Bengtson et al., 1990, and bradoriid Spinospitella coronata Skovsted et al., 2006, as well as the botsfordiid brachiopod Schizopholis yorkensis (Ushatinskaya and Holmer in Gravestock et al., 2001), in the overlying Holyoake Formation correlates the succession to the Dailyatia odyssei Zone (Cambrian Stages 3–4) in South Australia

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  • 44.
    Claybourn, Thomas
    et al.
    Department of Earth Sciences, Uppsala University.
    Skovsted, Christian
    Naturhistoriska riksmuseet, Enheten för paleobiologi.
    Betts, Marissa
    Palaeoscience Research Centre, School of Environmental and Rural Science, University of New England, Armidale.
    Holmer, Lars
    Department of Earth Sciences, Palaeobiology, Uppsala University.
    Bassett-Butt, Lucy
    Department of Earth Sciences, Palaeobiology, Uppsala University.
    Brock, Glenn
    Department of Biological Sciences, Macquarie University.
    Camenellan tommotiids from the Cambrian Series 2 of East Antarctica: biostratigraphy, palaeobiogeography, and systematics2021Inngår i: Acta Palaeontologica Polonica, ISSN 0567-7920, E-ISSN 1732-2421, Vol. 66, s. 207-229Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Cambrian Series 2 shelly fossils from thick carbonate successions in East Antarctica have received limited systematic treatment through the 20th century. Described here are the East Antarctic camenellan tommotiids from the Shackleton Limestone in the Central Transantarctic Mountains and the Schneider Hills limestone in the Argentina Range. This material comes from both newly sampled collections and incompletely described material from older collections. The assemblage supports correlation to the Dailyatia odyssei Zone and Pararaia janeae Trilobite Zone of South Australia, with the newly examined specimens of Dailyatia decobruta from the Shackleton Limestone providing direct correlation to the Mernmerna Formation of the Ikara-Flinders Ranges and White Point Conglomerate of Kangaroo Island. These East Antarctic assemblages include five species referred to Dailyatia, in addition to an undetermined kennardiid species and fragments of the problematic Shetlandia multiplicata. The results further corroborate the notion that fossiliferous carbonate clasts found on King George Island were sourced from the same carbonate shelf as the Shackleton Limestone, with the taxon S. multiplicata found in both units. The Schneider Hills limestone in the Argentina Range has yielded sclerites of Dailyatia icari sp. nov., currently only known from this location. 

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  • 45. Crane, Peter Robert
    et al.
    Friis, Else Marie
    Naturhistoriska riksmuseet, Enheten för paleobiologi.
    Water lilies, loss of woodiness, and model systems2020Inngår i: Proceedings of the National Academy of Sciences, Vol. 117, s. 9674-9676Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The delicate necklace of threaded petals from the tomb of Rameses II, mid-nineteenth century glasshouses built for the newly discovered Victoria amazonica, and Monet’s giant canvases in the Mus´ee de l’Orangerie all testify to a deep human attraction to waterlilies: beguiling plants with showy flowers that seem toarise nymph-like out of the mud. Like orchids, cacti, succulents, and carnivorous plants, water lilies have a dedicated band of horticulturalists devoted to growing and exploring their endless variety. The late nineteenth century craze for water lilies that attracted Monet was fueled by one such enthusiast, Joseph Bory Latour-Marliac, who developed hardy waterlily cultivars with dazzling new flower colors ranging from “delicate yellow to fuscia and deep red.” Nymphaea thermarum, the focus of the recent paper by Povilus et al., is another unusual water lily variant. The smallest water lily known, N. thermarum was discovered and described in the late 1980s. Endemic to hot spring lakes in the Albertine Rift Valley of Rwanda, now, just a few decades after its discovery,it appears to be extinct in the wild.

  • 46.
    Cui, Ying
    et al.
    Department of Geosciences, The Pennsylvania State University, University Park, PA, United States.
    Bercovici, Antoine
    Department of Geology, Lund University, Lund, Sweden.
    Yu, Jianxin
    State Key Laboratory of Biogeology and Environmental Geology of Ministry of Education, China University of Geosciences (Wuhan), People's Republic of China.
    Kump, Lee R.
    Department of Geosciences, The Pennsylvania State University, University Park, PA, United States.
    Freeman, Katherine
    Department of Geosciences, The Pennsylvania State University, University Park, PA, United States.
    Su, Shangguo
    School of Earth Sciences and Resources, China University of Geosciences (Beijing), People's Republic of China.
    Vajda, Vivi
    Naturhistoriska riksmuseet, Enheten för paleobiologi. Department of Geology, Lund University, Sweden.
    Carbon cycle perturbation expressed in terrestrial Permian–Triassic boundary sections in South China2017Inngår i: Global and Planetary Change, ISSN 0921-8181, E-ISSN 1872-6364, Vol. 148, s. 272-285Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Stable isotopes of inorganic and organic carbon are commonly used in chemostratigraphy to correlatemarine andterrestrial sedimentary sequences based on the assumption that the carbon isotopic signature of the exogenic carbon pool dominates other sources of variability. Here, sediment samples fromfour Permian–Triassic boundary (PTB) sections ofwesternGuizhou and eastern Yunnan provinces in South China, representing a terrestrial tomarine transitional setting,were analyzed for δ13C of organic matter (δ13Corg). These valueswere subsequently compared to published δ13C values of carbonates (δ13Ccarb) from the Global Stratotype Section and Point at Meishan and many other marine and terrestrial sections. A similar isotopic trend evident through all four sections is characterized by a negative shift of 2–3‰ at the top of the Xuanwei Formation, where we tentatively place the PTB. This negative shift also corresponds to a turnover in the vegetation and the occurrence of fungal spores, which is generally interpreted as a proliferation of decomposers and collapse of complex ecosystems during the end-Permian mass extinction event. Moreover, the absolute values of δ13Corg are more extreme in the more distal (marine) deposits. The δ13Corg values for the studied sediments aremore variable compared to coeval δ13Ccarb records from marine records especially in the interval below the extinction horizon. We contend that the depositional environment influenced the δ13Corg values, but that the persisting geographic δ13Corg pattern through the extinction event across the four independent sections is an indication that the atmospheric δ13C signal left an indelible imprint on the geologic record related to the profound ecosystem change during the end-Permian extinction event.

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  • 47.
    Cunningham, John A.
    et al.
    Naturhistoriska riksmuseet, Enheten för paleobiologi. University of Bristol.
    Vargas, Kelly
    School of Earth Sciences, University of Bristol, Bristol.
    Yin, Zongjun
    State Key Laboratory of Palaeobiology and Stratigraphy, Nanjing Institute of Geology and Palaeontology, Chinese Academy of Sciences, Nanjing.
    Bengtson, Stefan
    Naturhistoriska riksmuseet, Enheten för paleobiologi.
    Donoghue, Philip C.J.
    University of Bristol.
    The Weng’an Biota (Doushantuo Formation): an Ediacaran window on soft bodied and multicellular microorganisms.2017Inngår i: journal of the geological society, ISSN 2041-479X, Vol. 174, nr 5, s. 793-802Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The Weng’an Biota is a fossil Konservat-Lagerstätte in South China that is approximately 570-600 million years old and provides an unparalleled snapshot of marine life during the interval in which molecular clocks estimate that animal clades were diversifying. It yields specimens that are three-dimensionally preserved in calcium phosphate with cellular and sometimes subcellular fidelity. The biota includes candidates for the oldest animals in the fossil record, including embryonic, larval and adult forms. We argue that, while the Weng’an Biota includes forms that could be animals, none can currently be assigned to this group with confidence. Nonetheless, the biota offers a rare and valuable window on the evolution of multicellular and soft-bodied organisms in the prelude to the Cambrian radiation.

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  • 48.
    Dagtekin, Dilsad
    et al.
    Eurasia Institute of Earth Sciences, Istanbul Technical University.
    Sahan, Evrim A.
    Naturhistoriska riksmuseet, Enheten för paleobiologi.
    Denk, Thomas
    Naturhistoriska riksmuseet, Enheten för paleobiologi.
    Köse, Nesibe
    Department of Forest Botany, Faculty of Forestry, Istanbul University-Cerrahpasa.
    Dalfes, H. Nüzhet
    Eurasia Institute of Earth Sciences, Istanbul Technical University, Istanbul.
    Past, present and future distributions of Oriental beech (Fagus orientalis) under climate change projections2020Inngår i: PLOS ONE, E-ISSN 1932-6203, Vol. 15, nr 11, s. 1-19, artikkel-id e0242280Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Species distribution models can help predicting range shifts under climate change. The aimof this study is to investigate the late Quaternary distribution of Oriental beech (Fagus orientalis)and to project future distribution ranges under different climate change scenarios usinga combined palaeobotanical, phylogeographic, and modelling approach. Five species distributionmodelling algorithms under the R-package ‘biomod2‘were applied to occurrence dataof Fagus orientalis to predict distributions under present, past (Last Glacial Maximum, 21ka, Mid-Holocene, 6 ka), and future climatic conditions with different scenarios obtainedfrom MIROC-ESM and CCSM4 global climate models. Distribution models were comparedto palaeobotanical and phylogeographic evidence. Pollen data indicate northern Turkey andthe western Caucasus as refugia for Oriental beech during the Last Glacial Maximum.Although pollen records are missing, molecular data point to Last Glacial Maximum refugiain northern Iran. For the mid-Holocene, pollen data support the presence of beech in thestudy region. Species distribution models predicted present and Last Glacial Maximum distributionof Fagus orientalis moderately well yet underestimated mid-Holocene ranges.Future projections under various climate scenarios indicate northern Iran and the Caucasusregion as major refugia for Oriental beech. Combining palaeobotanical, phylogeographicand modelling approaches is useful when making projections about distributions of plants.Palaeobotanical and molecular evidence reject some of the model projections. Nevertheless,the projected range reduction in the Caucasus region and northern Iran highlights theirimportance as long-term refugia, possibly related to higher humidity, stronger environmentaland climatic heterogeneity and strong vertical zonation of the forest vegetation.

    Fulltekst (pdf)
    Dagtekin et al 2020 F orientalis
  • 49. Dalsätt, J
    et al.
    Zhou, Z
    Zhang, F
    Ericson, Per G P
    Naturhistoriska riksmuseet, Forskningsavdelningen centralt.
    Food remains in Confuciusornis sanctus suggest a fish diet.2006Inngår i: Die Naturwissenschaften, ISSN 0028-1042, E-ISSN 1432-1904, Vol. 93, nr 9, s. 444-6Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Despite hundreds of excellent fossils of Confuciusornis, the most abundant group of birds in the Early Cretaceous, 'Jehol Biota' in China, there is yet no indication of the food choice of these birds. Here, we describe fish remains preserved in the alimentary system of a specimen of Confuciusornis sanctus from the Jiufotang Formation. This find is about five million years younger than all previously published confuciusornithid birds from the Yixian Formation. Although it is unknown how common fish was in the diet of Confuciusornis, the find does not support previous hypotheses that it fed on plants or grain.

  • 50.
    Dalsätt, Johan
    et al.
    Naturhistoriska riksmuseet, Enheten för zoologi.
    Mörs, Thomas
    Naturhistoriska riksmuseet, Enheten för paleobiologi.
    Ericson, Per G P
    Naturhistoriska riksmuseet, Forskningsavdelningen centralt.
    Fossil birds from the Miocene and Pliocene of Hambach (NW Germany)2006Inngår i: Palaeontographica. Abteilung A, Palaozoologie, Stratigraphie, ISSN 0375-0442, Vol. 277, nr 1-6, s. 113-+Artikkel i tidsskrift (Fagfellevurdert)
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