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  • 1.
    Denk, Thomas
    et al.
    Swedish Museum of Natural History, Department of Paleobiology.
    Güner, H. Tuncay
    Swedish Museum of Natural History, Department of Paleobiology. Istanbul University Cerrahpaşa, Faculty of Forestry, Department of Forest Botany, 34473 Bahçeköy, Istanbul, Turkey.
    Bouchal, Johannes M.
    Swedish Museum of Natural History, Department of Paleobiology.
    Early Miocene climate and biomes of Turkey: Evidence from leaf fossils, dispersed pollen, and petrified wood2019In: Palaeogeography, Palaeoclimatology, Palaeoecology, ISSN 0031-0182, E-ISSN 1872-616X, Vol. 530, p. 236-248Article in journal (Refereed)
    Abstract [en]

    The early Miocene was a period of major palaeogeographic reorganization in the eastern Mediterranean region, during which time the Anatolian Plateau became subaerial and several intracontinental basins intermittently became connected to the Paratethys and Mediterranean seas. In this paper, we analyse early Miocene vegetation and climate using leaf records, palynological assemblages, and fossil wood at 36 localities from western and central Turkey, most of which have precise age control based on radiometric dating and mammal faunal ages. Using the leaf flora of Güvem (Beş Konak, Keseköy), Climate Leaf-Analysis Multivariate Program (CLAMP) analyses and Köppen signatures were employed to infer a palaeoclimate typical of modern laurel forest regions. Based on the palynological records, abundance of various pollen-taxa was used as a measure of openness of vegetation and regional presence of major tree taxa. Most pollen floras are dominated by tree pollen (ranging from 85 to 98%) and indicated widespread afforestation. In the pollen diagrams, shifts in dominance from swamp forest elements (Taxodioideae) to well-drained forests (Pinaceae) indicate changes in lake levels or phases of basin development. Such shifts may have been associated with the development of more xeric forest vegetation. Wood anatomical features such as false tree rings further may indicate seasonal climate. Pollen diagrams and macrofossils reflect zonal and azonal broadleaf and needleleaf forest and extrazonal open vegetation. The latter occurred in areas with shallow soils on volcanic rocks or limestone (e.g. cycads, Dracaena), or coastal areas (herb dominance). Taxonomic composition and biogeographic affinities suggest laurel forest as a major forest biome on well-drained soils and ecotones between laurel forest and broadleaf deciduous forest biomes. A comparison with younger floras shows that these are neither more diverse nor more warmth-loving despite an increase in global temperature (Mid-Miocene Climatic Optimum) suggesting bottlenecks during previous (Oligocene) cooler times for warmth-loving taxa.

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  • 2.
    Hagström, Jonas
    et al.
    Swedish Museum of Natural History, Department of Paleobiology.
    Hryniewicz, Krzysztof
    Hammer, Øyvind
    Kaim, Andrzej
    Little, Crispin T.S.
    Nakrem, Hans Arne
    Late Jurassic–Early Cretaceous hydrocarbon seep boulders from NovayaZemlya and their faunas2015In: Palaeogeography, Palaeoclimatology, Palaeoecology, ISSN 0031-0182, E-ISSN 1872-616X, Vol. 436, p. 231-244Article in journal (Refereed)
    Abstract [en]

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

  • 3.
    Kiel, Steffen
    et al.
    Swedish Museum of Natural History, Department of Paleobiology.
    Amano, Kazutaka
    Jenkins, Robert G.
    Predation scar frequencies in chemosymbiotic bivalves at an Oligocene seep deposit and their potential relation to inferred sulfide tolerances2016In: Palaeogeography, Palaeoclimatology, Palaeoecology, ISSN 0031-0182, E-ISSN 1872-616X, Vol. 453, p. 139-145Article in journal (Refereed)
  • 4.
    Li, Jianguo
    et al.
    Nanjing Institute of Geology and Palaeontology.
    Sha, Jingeng
    Nanjing Institute of Geology and Palaeontology.
    McLoughlin, Stephen
    Swedish Museum of Natural History, Department of Paleobiology.
    Wang, Xiaoming
    Natural History Museum of Los Angeles County.
    Mesozoic and Cenozoic palaeogeography, palaeoclimate and palaeoecology in theeastern Tethys2019In: Palaeogeography, Palaeoclimatology, Palaeoecology, ISSN 0031-0182, E-ISSN 1872-616X, Vol. 515, p. 1-5Article in journal (Refereed)
    Abstract [en]

    It is now more than 100years since Suess advanced the concept of the Tethys Ocean in 1893. Since the 1960s when the theory of plate tectonics became established, the Tethys region has attracted the attention of many geologists because it has experienced a complex evolution involving numerous continental fragments drifting in several discrete stages from the Gondwanan margin in the Southern Hemisphere northward to amalgamate with Eurasia in the Northern Hemisphere. The subsequent orogenies associated with consecutive microplate collisions caused great changes to the regional topography and environments, which researchers now realize had global impacts on climate, biotic evolution, and biogeography.

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  • 5.
    McLoughlin, Stephen
    et al.
    Swedish Museum of Natural History, Department of Paleobiology.
    Bomfleur, Benjamin
    Swedish Museum of Natural History, Department of Paleobiology.
    Biotic interactions in an exceptionallywell preserved osmundaceous fern rhizome from the Early Jurassic of Sweden2016In: Palaeogeography, Palaeoclimatology, Palaeoecology, ISSN 0031-0182, E-ISSN 1872-616X, Vol. 464, p. 86-96Article in journal (Refereed)
    Abstract [en]

    A remarkably well permineralized osmundaceous rhizome from the Early Jurassic of southern Sweden yields evidence of an array of interactions with other organisms in its immediate environment. These include epiphytism by a herbaceous heterosporous lycopsid; putative oribatid mite herbivory and detritivory (petiole and detritus borings and coprolites); potential pathogenic, saprotrophic or mycorrhizal interactions between fungi and the host plant and its epiphytes; parasitism or saprotrophy by putative peronosporomycetes; and opportunistic or passivemycophagy by oribatid mites evidenced by fungal spores in coprolites. A combination of abrupt burial by lahar deposits and exceedingly rapid permineralization by precipitation of calcite from hydrothermal brines facilitated the exquisite preservation of the rhizome and its component community of epiphytes, herbivores, saprotrophs and parasites. Ancient ferns with a rhizome cloaked by a thick mantle of persistent leaf bases and adventitious roots have a high potential for preserving macro-epiphytes and associated micro-organisms, and are especially promising targets for understanding the evolution of biotic interactions in forest understorey ecosystems.

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  • 6.
    McLoughlin, Stephen
    et al.
    Swedish Museum of Natural History, Department of Paleobiology.
    Haig, David W.
    Centre for Energy Geoscience, School of Earth Sciences, The University of Western Australia, Perth 6009, Australia.
    Siversson, Mikael
    Department of Earth and Planetary Sciences, Western Australian Museum, Welshpool, WA 6106, Australia.
    Einarsson, Elisabeth
    Department of Geology, Lund University, S-223 62 Lund, Sweden.
    Did mangrove communities exist in the Late Cretaceous of the Kristianstad Basin, Sweden?2018In: Palaeogeography, Palaeoclimatology, Palaeoecology, ISSN 0031-0182, E-ISSN 1872-616X, Vol. 498, p. 99-114Article in journal (Refereed)
    Abstract [en]

    Previous inferences of oyster-dominated communities occupying mangrove-like depositional settings in the Kristianstad Basin, Sweden, during the late early Campanian are reassessed. A significant percentage of oysters (Acutostrea incurva) from the Belemnellocamax mammillatus zone in Bed 3 at Åsen bear indentations on their left valves indicating attachment to plant axes. Many of these axes bear morphological features characteristic of the distal subaerial portions of woody plant branches and appear to have been rafted into the marine environment rather than representing in situ mangrove stems and roots. Foraminiferal assemblages recovered from sediment within the oyster body cavities differ from modern mangrove-community associations by the absence of siliceous agglutinated Foraminifera, the presence of diverse and relatively abundant Lagenida, relatively common triserial Buliminida, and a notable percentage of planktonic taxa. Chondrichthyan teeth assemblages from the same beds are similarly incompatible with the interpretation of a mangrove depositional environment based on comparisons with the distribution of related extant taxa. Apart from oyster shells and belemnite rostra, these beds are notably depauperate in diversity and abundance of macroinvertebrate remains compared with coeval carbonate shoal and rocky shoreline assemblages from the same basin. The collective palaeontological and sedimentological evidence favours an inner neritic sandy-substrate setting, but not nearshore or mangrove-like depositional environment for the oyster-rich Bed 3 at Åsen. The absence of mangrove-like assemblages at Åsen is consistent with the development of modern mangrove ecosystems much later (during the Maastrichtian and Cenozoic) based on the global palynological record.

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  • 7.
    McLoughlin, Stephen
    et al.
    Swedish Museum of Natural History, Department of Paleobiology.
    Pott, Christian
    LWL-Museum of Natural History, Münster, Germany.
    Plant mobility in the Mesozoic: Disseminule dispersal strategies of Chineseand Australian Middle Jurassic to Early Cretaceous plants2019In: Palaeogeography, Palaeoclimatology, Palaeoecology, ISSN 0031-0182, E-ISSN 1872-616X, Vol. 515, p. 47-69Article in journal (Refereed)
    Abstract [en]

    Four upper Middle Jurassic to Lower Cretaceous lacustrine Lagerstätten in China and Australia (the Daohugou, Talbragar, Jehol, and Koonwarra biotas) offer glimpses into the representation of plant disseminule strategies during that phase of Earth history in which flowering plants, birds, mammals, and modern insect faunas began to diversify. No seed or foliage species is shared between the Northern and Southern Hemisphere fossil sites and only a few species are shared between the Jurassic and Cretaceous assemblages in the respective regions. Freesporing plants, including a broad range of bryophytes, are major components of the studied assemblages and attest to similar moist growth habitats adjacent to all four preservational sites. Both simple unadorned seeds and winged seeds constitute significant proportions of the disseminule diversity in each assemblage. Anemochory, evidenced by the development of seed wings or a pappus, remained a key seed dispersal strategy through the studied interval. Despite the rise of feathered birds and fur-covered mammals, evidence for epizoochory is minimal in the studied assemblages. Those Early Cretaceous seeds or detached reproductive structures bearing spines were probably adapted for anchoring to aquatic debris or to soft lacustrine substrates. Several relatively featureless seeds in all assemblages were potentially adapted to barochory or to endozoochory—the latter evidenced especially by the presence of smooth seeds in vertebrate gut contents and regurgitant or coprolitic masses. Hydrochory is inferred for several aquatic plants that notably bear small featureless seeds, particularly aggregated into detachable pods.

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  • 8.
    Peterffy, Olof
    et al.
    Department of Geology, Lund University.
    Calner, Michael
    Department of Geology, Lund University.
    Vajda, Vivi
    Swedish Museum of Natural History, Department of Paleobiology. Department of Geology, Lund University, Sweden.
    Early Jurassic microbial mats—A potential response to reduced biotic activity in the aftermath of the end-Triassic mass extinction event2016In: Palaeogeography, Palaeoclimatology, Palaeoecology, ISSN 0031-0182, E-ISSN 1872-616X, Vol. 464, p. 76-85Article in journal (Refereed)
    Abstract [en]

    Wrinkle structures are microbially induced sedimentary structures (MISS) formed by cyanobacteria and are common in pre-Cambrian and Cambrian siltstones and sandstones but are otherwise rare in the Phanerozoic geological record. This paper reports the first discovery of Mesozoic wrinkle structures from Sweden. These are preserved in fine-grained and organic-rich heterolithic strata of the Lower Jurassic (Hettangian) Höganäs Formation in Skåne, southern Sweden. The strata formed in a low-energy, shallowsubtidal setting in themarginal parts of the Danish rift-basin. Palynological analyses of fine-grained sandstones hosting the wrinkle structures show that the local terrestrial environment probably consisted of a wetland hosting ferns, cypress and the extinct conifer family Cheirolepidaceae. Palynostratigraphy indicates a Hettangian age, stillwithin the floral recovery phase following the end-Triassic mass extinction event. The finding of wrinkle structures is significant as the presence of microbial mats in the shallow subtidal zone, (in a deeper setting compared to where modern epibenthic microbial mats grow) suggests decreased benthic biodiversity and suppressed grazing in shallow marine environments in the early aftermath of the end-Triassic mass extinction event.

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  • 9.
    Skovsted, Christian
    et al.
    Swedish Museum of Natural History, Department of Paleobiology.
    Bing, Pan
    Topper, Timothy, P.
    Betts, Marissa, J.
    Li, Guoxiang
    Brock, Glenn, A.
    The operculum andmode of life of the lower Cambrian hyolith Cupitheca from South Australia and North China2016In: Palaeogeography, Palaeoclimatology, Palaeoecology, ISSN 0031-0182, E-ISSN 1872-616X, Vol. 443, p. 123-130Article in journal (Refereed)
    Abstract [en]

    The operculum of the problematic tubular fossil Cupitheca holocyclata Bengtson in Bengtson et al., (1990) is described for the first time based on collections from South Australia and North China. The phosphatized sub-circular operculum exhibits well defined cardinal processes and a narrow cardinal shield unequivocally demonstrating that Cupitheca is a hyolith, probably an orthothecid. C. holocyclata has an almost global distribution in Cambrian Stages 3–4. The apical structure of the operculum is an elevated, disc-shaped platform with a concave base and a marginal rim that could represent the scar of a specialized larval attachment structure, perhaps anchoring the larval hyolith to a sediment grain, algae or other benthic substrate. Cupitheca probably had a pelagic larval stage and settled on the seafloor by attachment of the apical disc to suitable substrates before developing a free-living benthic adult lifestyle. This contrasting mode of life compared to other hyolith genera suggests that the group had already evolved a range of distinct lifestyles in the Cambrian, providing significant clues into their ecology and distribution.

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  • 10. Slater, Sam
    Episodic river flooding events revealed by palynological assemblages inJurassic deposits of the Brent Group, North Sea2017In: Palaeogeography, Palaeoclimatology, Palaeoecology, ISSN 0031-0182, E-ISSN 1872-616XArticle in journal (Refereed)
  • 11.
    Slater, Sam
    et al.
    Swedish Museum of Natural History, Department of Paleobiology.
    McKie, Tom
    Shell UK Ltd., 1 Altens Farm Road, Nigg, Aberdeen AB12 3FY, UK.
    Vieira, Manuel
    UK Ltd., 1 Altens Farm Road, Nigg, Aberdeen AB12 3FY, UK.
    Wellmann, Charles
    Department of Animal and Plant Sciences, University of Sheffield, Alfred Denny Building,Western Bank, Sheffield S10 2TN, UK.
    Vajda, Vivi
    Swedish Museum of Natural History, Department of Paleobiology. Department of Geology, Lund University, Sweden.
    Episodic river flooding events revealed by palynological assemblages inJurassic deposits of the Brent Group, North Sea2017In: Palaeogeography, Palaeoclimatology, Palaeoecology, ISSN 0031-0182, E-ISSN 1872-616X, Vol. 485, p. 389-400Article in journal (Refereed)
    Abstract [en]

    Spore and pollen (sporomorph) assemblages from Middle Jurassic marine deposits of the Brent Group in the northern North Sea are investigated to assess temporal and spatial variations in vegetation and depositional processes. Four wells were sampled for palynology from the Penguins Cluster and the Don North East fields through the Rannoch Formation shoreface succession. Hyperpycnite deposits occur throughout, but are concentrated within the lower part of the section. These are expressed by sand-prone beds displaying waxing and waning current motifs, normally graded muddy beds and structureless mudstones. Hyperpycnal/hypopycnal deposits resulting from episodic river flooding represent important sedimentary features as they may be preserved below fair weather wave base in more offshore settings and potentially be the only record of the former presence of a nearby river mouth. The hyperpycnites typically contain abundant Botryoccocus spp., Amorphous Organic Matter (AOM) and hinterland sporomorph taxa with relatively few marine components compared to associated marine shoreface facies. Variations in palynofacies assemblages and Botryococcus spp. abundances indicate frequent river mouth avulsion. Ordination of samples using non-metric multidimensional scaling (NMDS) indicates that shoreface samples of the sampled wells are relatively distinct, but hyperpycnite samples are highly similar regardless of their sampled well. This suggests that depositional processes and spore/pollen sources (i.e. catchment zones) were similar among hyperpycnite events across different wells. Abundant bisaccate pollen, Botryococcus spp. and AOM within interpreted hyperpycnites suggest sediment mixing along the fluvial drainage path during flooding events. The terrestrial signature of hyperpycnite sporomorph assemblages demonstrates that underflows remained coherent as they descended the shoreface profile with little turbulent mixing with ambient marine waters. Sporomorph assemblages display few large changes through time suggesting vegetation on the adjacent coastal plain was relatively static through the studied interval.

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  • 12.
    Steinthorsdottir, Margret
    Department of Geological Sciences and Bolin Centre for Climate Research, Stockholm University.
    Pole, Mike
    Nanjing Institute of Geology and Palaeontology, The Chinese Academy of Sciences.
    Global trends of pCO2 across the Cretaceous-Paleogene boundary supported by the first Southern Hemisphere stomatal proxy-based pCO2 reconstruction2016In: Palaeogeography, Palaeoclimatology, Palaeoecology, ISSN 0031-0182, E-ISSN 1872-616X, Vol. 464, p. 143-152Article in journal (Refereed)
    Abstract [en]

    Reliable reconstructions of atmospheric carbon dioxide concentrations (pCO2) are required at higher resolution than currently available to help resolve the relationship between mass extinctions and changes in palaeo-pCO2 levels. Such reconstructions are needed: 1, at a high temporal resolution for constraining the pre- and post-extinction atmospheres; and 2, at a sufficient spatial resolution to constrain potential inter-hemispheric differences. Here we estimate pCO2 based on fossil Lauraceae leaf cuticle specimens derived from three localities with strata spanning the latest Cretaceous to the mid-Paleocene, including a new Cretaceous–Paleogene boundary (K–Pg) locality, in New Zealand. We use two independent methods of stomatal density-based pCO2 reconstructions; a transfer function calibrated using herbarium material and the stomatal ratio method, producing three calibration sets. Our results based on the mean values of each of the three calibration methods indicate pCO2 ranging between ca. 460 and 650 ppm during the latest Cretaceous, falling precipitously to average values between ca. 360 and 430 ppm across the K–Pg boundary, and further to ca. 305–320 ppm in the mid-Paleocene. A ‘spike’ of extremely high pCO2 at the K–Pg could not be confirmed, but our results are, nonetheless, consistent with previously published pCO2 records from the Northern Hemisphere, and show that stomatal density worldwide was responding to significant changes in pCO2 across the K–Pg.

  • 13.
    Steinthorsdottir, Margret
    et al.
    Swedish Museum of Natural History, Department of Paleobiology. Bolin Centre for Climate Research, Stockholm University.
    Vajda, Vivi
    Swedish Museum of Natural History, Department of Paleobiology. Department of Geology, Lund University, Sweden.
    Pole, Mike
    Queensland Herbarium, Brisbane Botanic Gardens, Mt. Coot-tha, Mt. Coot-tha Rd., Toowong, QLD 4066, Australia.
    Global trends of pCO2 across the Cretaceous–Paleogene boundary supported by the first Southern Hemisphere stomatal proxy-based pCO2 reconstruction2016In: Palaeogeography, Palaeoclimatology, Palaeoecology, ISSN 0031-0182, E-ISSN 1872-616X, Vol. 464, p. 143-152Article in journal (Refereed)
    Abstract [en]

    Reliable reconstructions of atmospheric carbon dioxide concentrations (pCO2) are required at higher resolution than currently available to help resolve the relationship between mass extinctions and changes in palaeo-pCO2 levels. Such reconstructions are needed: 1, at a high temporal resolution for constraining the pre- and post- extinction atmospheres; and 2, at a sufficient spatial resolution to constrain potential inter-hemispheric differ- ences. Here we estimate pCO2 based on fossil Lauraceae leaf cuticle specimens derived from three localities with strata spanning the latest Cretaceous to the mid-Paleocene, including a new Cretaceous–Paleogene bound- ary (K–Pg) locality, in New Zealand. We use two independent methods of stomatal density-based pCO2 recon- structions; a transfer function calibrated using herbarium material and the stomatal ratio method, producing three calibration sets. Our results based on the mean values of each of the three calibration methods indicate pCO2 ranging between ca. 460 and 650 ppm during the latest Cretaceous, falling precipitously to average values between ca. 360 and 430 ppm across the K–Pg boundary, and further to ca. 305–320 ppm in the mid-Paleocene. A ‘spike’ of extremely high pCO2 at the K–Pg could not be confirmed, but our results are, nonetheless, consistent with previously published pCO2 records from the Northern Hemisphere, and show that stomatal density world- wide was responding to significant changes in pCO2 across the K–Pg. 

  • 14.
    Steinthorsdottir, Margret
    et al.
    Swedish Museum of Natural History, Department of Paleobiology. Bolin Centre for Climate Research, Stockholm University.
    Vajda, Vivi
    Swedish Museum of Natural History, Department of Paleobiology. Department of Geology, Lund University, Sweden.
    Pole, Mike
    Significant transient pCO2 perturbation at the New Zealand Oligocene- Miocene transition recorded by fossil plant stomata2018In: Palaeogeography, Palaeoclimatology, Palaeoecology, ISSN 0031-0182, E-ISSN 1872-616X, Vol. 515, p. 152-161Article in journal (Refereed)
    Abstract [en]

    The reorganisation of Earth's climate system from the Oligocene to the Miocene was influenced by complex interactions between Tethyan tectonics, orbital parameters, oceanographic changes, and carbon cycle feedbacks, with climate modelling indicating that pCO2 was an important factor. Oscillating episodes of climate change during the Oligocene–Miocene transition (OMT) have however been difficult to reconcile with existing pCO2 records. Here we present a new pCO2 record from the OMT into the early Miocene, reconstructed using the stomatal proxy method with a database of fossil Lauraceae leaves from New Zealand. The leaf database derives from three relatively well-dated sites located in the South Island of New Zealand; Foulden Maar, Mataura River and Grey Lake. Atmospheric pCO2 values were obtained based on four separate calibrations with three nearest living equivalents, using the stomatal ratio method as well as transfer functions. Our results, based on the mean values of each of the four calibrations, indicate pCO2 ranging ~582–732 ppm (average 650 ppm) at the OMT, falling precipitously to mean values of ~430–538ppm (average 492ppm) for the earliest Miocene and ~454–542 ppm (average 502 ppm) in the early Miocene. The much higher values of pCO2 at the OMT indicate that pCO played an important role in climate dynamics during this time, potentially including the abrupt ter- mination of glaciations. 

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  • 15.
    Steinthorsdottir, Margret
    et al.
    Swedish Museum of Natural History, Department of Paleobiology. Bolin Centre for Climate Research, Stockholm University.
    Vajda, Vivi
    Swedish Museum of Natural History, Department of Paleobiology. Department of Geology, Lund University, Sweden.
    Pole, Mike
    Queensland Herbarium, Brisbane Botanic Gardens.
    Significant transient pCO2 perturbation at the New Zealand Oligocene-Miocene transition recorded by fossil plant stomata2019In: Palaeogeography, Palaeoclimatology, Palaeoecology, ISSN 0031-0182, E-ISSN 1872-616X, Vol. 515, p. 152-161Article in journal (Refereed)
    Abstract [en]

    The reorganisation of Earth's climate system from the Oligocene to the Miocene was in fluenced by complex interactions between Tethyan tectonics, orbital parameters, oceanographic changes, and carbon cycle feedbacks, with climate modelling indicating that pCO2 was an important factor. Oscillating episodes of climate change during the Oligocene-Miocene transition (OMT) have however been difficult to reconcile with existing pCO2 records. Here we present a new pCO2 record from the OMT into the early Miocene, reconstructed using the stomatal proxy method with a database of fossil Lauraceae leaves from New Zealand. The leaf database derives from three relatively well-dated sites located in the South Island of New Zealand; Foulden Maar, Mataura River and Grey Lake. Atmospheric pCO2 values were obtained based on four separate calibrations with three nearest living equivalents, using the stomatal ratio method as well as transfer functions. Our results, based on the mean values of each of the four calibrations, indicate pCO2 ranging ~582–732 ppm (average 650 ppm) at the OMT, falling precipitously to mean values of ~430–538 ppm (average 492 ppm) for the earliest Miocene and ~454–542 ppm (average 502 ppm) in the early Miocene. The much higher values of pCO2 at the OMT indicate that pCO played an important role in climate dynamics during this time, potentially including the abrupt termination of glaciations.

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  • 16. Strömberg, C. A. E.
    et al.
    Werdelin, Lars
    Swedish Museum of Natural History, Department of Paleobiology.
    Friis, Else Marie
    Saraç, G.
    The spread of grass-dominated habitats in the Eastern Mediterranean during the Cainozoic: phytolith evidence2007In: Palaeogeography, Palaeoclimatology, Palaeoecology, ISSN 0031-0182, E-ISSN 1872-616X, Vol. 250, p. 18-49Article in journal (Refereed)
    Abstract [en]

    The arrival of hipparionine horses in the eastern Mediterranean region around 11 Ma was traditionally thought to mark the simultaneous westward expansion of savanna vegetation across Eurasia. However, recent paleoecological reconstructions based on tooth wear, carbon isotopes, and functional morphology indicate that grasses played a minor role in Late Miocene ecosystems of the eastern Mediterranean, which were more likely dry woodlands or forests. The scarcity of grass macrofossils and pollen in Miocene floras of Europe and Asia Minor has been used to support this interpretation. Based on the combined evidence, it has therefore been suggested that Late Miocene ungulate faunal change in the eastern Mediterranean signals increased aridity and landscape openness, but not necessarily the development of grass-dominated habitats. To shed newlight on the Miocene evolution of eastern Mediterranean ecosystems, we used phytolith assemblages preserved in direct association with faunas as a proxy for paleovegetation structure (grassland vs. forest).We extracted phytoliths and other biogenic silica fromsediment samples fromwell-known Early to Late Miocene (∼20–7Ma) faunal localities in Greece, Turkey, and Iran. In addition, a Middle Eocene sample from Turkey yielded phytoliths and served as a baseline comparison for vegetation inference. Phytolith analysis showed that the Middle Eocene assemblage consists of abundant grass phytoliths (grass silica short cells) interpreted as deriving from bambusoid grasses, as well as diverse forest indicator phytoliths from dicotyledonous angiosperms and palms, pointing to the presence of a woodland or forest with abundant bamboos. In contrast, the Miocene assemblages are dominated by diverse silica short cells typical of pooid open-habitat grasses. Forest indicator phytoliths are also present, but are rare in the Late Miocene (9–7 Ma) assemblages. Our analysis of the Miocene grass community composition is consistent with evidence from stable carbon isotopes from paleosols and ungulate tooth enamel, showing that C4 grasses were rare in the Mediterranean throughout the Miocene. These data indicate that relatively open habitats had become common in Turkey and surrounding areas by at least the Early Miocene (∼20 Ma), N7 million years before hipparionine horses reached Europe and arid conditions ensued, as judged by faunal data.

  • 17.
    Vajda, Vivi
    Swedish Museum of Natural History, Department of Paleobiology. Department of Geology, Lund University, Sweden.
    Villanueva-Amadoz, Uxue
    ERNO, Instituto de Geología, UNAM, L.D. Colosio y Madrid.
    Lehsten, Veiko
    Dept of Physical Geography and Ecosystems Science, Lund University.
    Alcalá, Luis
    Fundación Conjunto Paleontológico de Teruel-Dinópolis/Museo Aragonés de Paleontología.
    Dietary and environmental implications of Early Cretaceous predatory dinosaur coprolites from Teruel, Spain2016In: Palaeogeography, Palaeoclimatology, Palaeoecology, ISSN 0031-0182, E-ISSN 1872-616X, Vol. 464, p. 134-142Article in journal (Refereed)
    Abstract [en]

    Coprolites from the Early Cretaceous vertebrate bone-bed at Ariño in Teruel, Spain, were analyzed geochemically and palynologically. They contain various inclusions, such as small bone fragments, abundant plant remains, pollen, and spores. We attribute the coprolites to carnivorous dinosaurs based partly on their morphology together with the presence of bone fragments, and a high content of calcium phosphate (hydroxylapatite) with calcite.Well-preserved pollen and spore assemblages were identified in all coprolite samples and a slightly poorer assemblage was obtained from the adjacent sediments, both indicating an Early Cretaceous (Albian) age. This shows that the coprolites are in situ and also confirms previous age determinations for the host strata. The depositional environment is interpreted as a continental wetland based on the palynoflora, which includes several hydrophilic taxa, together with sparse occurrences of fresh-water algae, such as Ovoidites, and the absence of marine palynomorphs. Although the coprolites of Ariño samples generally are dominated by pollen produced by Taxodiaceae (cypress) and Cheirolepidiaceae (a family of extinct conifers), the sediment samples have a slightly higher relative abundance of fern spores. The distribution of major organic components varies between the coprolite and sediment samples, which is manifest by the considerably higher charcoal percentage within the coprolites. The high quantities of charcoal might be explained by a ground-dwelling species, feeding on smaller vertebrates that complemented its diet with plant material from a paleoenvironment were wild fires were a part of the ecosystem. The state of preservation of the spores and pollen is also more detailed in the coprolites, suggesting that encasement in calcium phosphate may inhibit degradation of sporopollenin.

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  • 18.
    Vajda, Vivi
    Swedish Museum of Natural History, Department of Paleobiology. Department of Geology, Lund University, Sweden.
    Sha, Jingeng
    Nanjing Institute of Geology and Palaeontology, Academia Sinic.
    Mesozoic ecosystems – climate and biotas2016In: Palaeogeography, Palaeoclimatology, Palaeoecology, ISSN 0031-0182, E-ISSN 1872-616X, Vol. 464, p. 1-4Article in journal (Other academic)
    Abstract [en]

    This issue of Palaeogeography Palaeoclimatology Palaeoecology is devoted to papers on Mesozoic ecosystems and is an outcome of the International Geoscience Program (IGCP) 632. IGCP is a joint operation by UNESCO and the International Union of Geological Sciences (IUGS), which promote interdisciplinary Earth science research among scientists internationally. Since its formation in 1972, IGCP has supported over 500 projects in about 150 countries.

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  • 19. Vihtakari, M.
    et al.
    Renaud, P.
    Clarke, L.J.
    Whitehouse, Martin J.
    Swedish Museum of Natural History, Department of Geology.
    Hop, H.
    Carroll, M.L.
    Ambrose, W.
    Decoding the oxygen isotope signal for seasonal growth patterns in Arctic bivalves.2016In: Palaeogeography, Palaeoclimatology, Palaeoecology, ISSN 0031-0182, E-ISSN 1872-616X, Vol. 446, p. 263-283Article in journal (Refereed)
    Abstract [en]

    Chemical and physical variations in skeletal structures of marine organisms can reflect environmental variability, forming the basis for reconstructing the conditions in which the organism lived. The successful use of these bio-archives for reconstructing seasonal environmental conditions is dependent on understanding intra-annual growth patterns and timing of their deposition within skeletal structures. We studied intra-annual shell growth patterns, as well as the timing and environmental processes associated with winter growth line deposition in two circumpolar bivalve mollusks, Serripes groenlandicus and Ciliatocardium ciliatum. Shell growth deposited during a 1-year deployment on oceanographic moorings in Kongsfjorden and Rijpfjorden, Svalbard, was analyzed in situ for δ18O values using high spatial resolution secondary ion mass spectrometry (SIMS). A new digital method was developed to measure the location of SIMS spots along chronologically deposited shell material. Dynamic time warping algorithms were adapted to align SIMS-determined δ18O values with δ18O values predicted from continuous mooring instrument recordings of seawater temperature and salinity, in order to derive intra-annual shell growth models. The resulting growth models indicated that the prominent winter growth band was formed during a slow shell growth period lasting from December until May in Kongsfjorden and from November until mid-June in Rijpfjorden. The length of the slow growth period was most likely controlled by food availability. Shell growth rate during the growing season was significantly explained by temperature (marginal R2 = 0.29, p < 0.001) indicating that temperature partly drives shell growth rate when the food supply is sufficient. The insights into intra-annual shell growth of Arctic bivalves and the methods developed in our study are important contributions for further development of bivalve shells as proxy archives.

  • 20. Zaton, M
    et al.
    Niedzwiedzki, G
    Marynowski, L
    Benzerara, K
    Pott, Christian
    Swedish Museum of Natural History, Department of Paleobiology.
    Cosmidis, J
    Krzykawski, T
    Filipiak, P
    Coprolites of Late Triassic carnivorous vertebrates from Poland: An integrative approach2015In: Palaeogeography, Palaeoclimatology, Palaeoecology, ISSN 0031-0182, E-ISSN 1872-616X, Vol. 430, p. 21-46Article in journal (Refereed)
    Abstract [en]

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

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  • 21.
    Zhang, Zhiliang
    et al.
    Northwest university.
    Skovsted, Christian
    Swedish Museum of Natural History, Department of Paleobiology.
    Zhang, Zhifei
    Northwest University.
    A hyolithid without helens preserving the oldest hyolith muscle scars; palaeobiology of Paramicrocornus from the Shujingtuo Formation (Cambrian Series 2) of South China2018In: Palaeogeography, Palaeoclimatology, Palaeoecology, ISSN 0031-0182, E-ISSN 1872-616X, Vol. 489, p. 1-14Article in journal (Refereed)
    Abstract [en]

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

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