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  • 1.
    Hara, Urszula
    et al.
    Polish Geologi cal Institute – Nati onal Research Institute.
    Mörs, Thomas
    Naturhistoriska riksmuseet, Enheten för paleobiologi.
    Hagström, Jonas
    Naturhistoriska riksmuseet, Enheten för paleobiologi.
    Reguero, Marcelo A.
    Museo de La Plata, Di vi sion Paleontol ogia de Vertebrados.
    Eocene bryozoan assemblages from the La Meseta Formation of Seymour Island, Antarctica2018Ingår i: Geological Quarterly, ISSN 1641-7291, E-ISSN 2082-5099, Vol. 62, nr 3, s. 705-728Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Early to Late Eocene bryozoans from the La Meseta Formation of Seymour Island were collected at two localities within the Cucullaea I Allomember (Telm4 and Telm5) on the northwestern side of the island and in two localities within the Submeseta Allomember (Telm6 and Telm7) on the northeastern side. This fauna is represented by cyclostomes of the suborders Tubuliporina and Cerioporina and suborders of Neocheilostomata, among which nine species have been recognized. The following new species are introduced: Micropora nordenskjoeldi sp. nov., Lunulites marambionis sp. nov., Otionellinaantarctica sp. nov. and Otionellina eocenica sp. nov. Some other taxa recognized in the studied material, such as Reticrescis plicatus, Uharella seymourensis and Celleporaria mesetaensis, were previously described from the lower most (Telm1) or uppermost parts (Telm6–7), thus their stratigraphical ranges within the La Meseta Formation are extended. The diverse...

  • 2.
    Hagström, Jonas
    Naturhistoriska riksmuseet, Enheten för paleobiologi.
    Where Swedish polar research began: the Linnaean apostle Anton Rolandson Martin’s voyage to Spitsbergen in 17582018Ingår i: Polar Record, ISSN 0032-2474, E-ISSN 1475-3057, Vol. 54, s. 36-42Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    In 1758 the renowned Swedish botanist Carl Linnaeus sent his student Anton Rolandson Martin to the Arctic on-board a whaler to collect scientific specimens. He became the first Swedish scientist to sail these northern waters and to set foot on Spitsbergen. But what route did the ship take and where exactly did he land? By using a combination of geographical information in Martin’s diary together with latitude and wind directions from his meteorological records the ship’s voyage has been reconstructed. The whaler set course directly to the west coast of Spitsbergen and then patrolled waters from there to the eastern flank of the ice fields off Greenland. The ship then returned to Spitsbergen as the whaling season drew to an end. Martin got the chance to set foot on land only once and for just two hours. After recent field work at the presumed locality 258 years after Martin’s visit, his descriptions of the islets were checked and a first-hand comparison was made between the rock sample Martin brought home and the local bedrock. The author is now confident that the landing took place on Forlandsøyane islands, situated off the southwestern coast of Prins Karls Forland.

  • 3.
    ACOSTA HOSPITALECHE, Carolina
    et al.
    División Paleontología Vertebrados, Museo de La Plata, Paseo del Bosque s/n, B1900FWA, La Plata, Argentina.
    HAGSTRÖM, Jonas
    Naturhistoriska riksmuseet, Enheten för paleobiologi.
    REGUERO, Marcelo
    División Paleontología Vertebrados, Museo de La Plata, Paseo del Bosque s/n, B1900FWA, La Plata and Instituto Antártico Argentino (Dirección Nacional del Antártico), 25 de mayo 1143, San Martín, Argentina.
    Historical perspective of Otto Nordenskjöld´s Antarctic fossil penguin collection and Carl Wiman’s contribution2017Ingår i: Polar Record, ISSN 0032-2474, E-ISSN 1475-3057, Vol. 53, nr 4, s. 364-375Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The early explorer and scientist Otto Nordenskjöld, leader of the Swedish South Polar Expedition of 1901–1903, was the first to collect Antarctic penguin fossils. The site is situated in the northeastern region of Seymour Island and constitutes one of the most important localities in the study of fossilised penguins. The task of describing these specimens together with fossilised whale remains was given to Professor Carl Wiman (1867–1944) at Uppsala University, Sweden. Although the paradigm for the systematic study of penguins has changed considerably over recent years, Wiman's contributions are still remarkable. His establishment of grouping by size as a basis for classification was a novel approach that allowed them to deal with an unexpectedly high morphological diversity and limited knowledge of penguin skeletal anatomy. In the past, it was useful to provide a basic framework for the group that today could be used as ‘taxon free’ categories. First, it was important to define new species, and then to establish a classification based on size and robustness. This laid the foundation for the first attempts to use morphometric parameters for the classification of isolated penguin bones. The Nordenskjöld materials constitute an invaluable collection for comparative purposes, and every year researchers from different countries visit this collection.

  • 4.
    Hagström, Jonas
    et al.
    Naturhistoriska riksmuseet, Enheten för paleobiologi.
    Hryniewicz, Krzysztof
    Hammer, Øyvind
    Kaim, Andrzej
    Little, Crispin T.S.
    Nakrem, Hans Arne
    Late Jurassic–Early Cretaceous hydrocarbon seep boulders from NovayaZemlya and their faunas2015Ingår i: Palaeogeography, Palaeoclimatology, Palaeoecology, ISSN 0031-0182, E-ISSN 1872-616X, Vol. 436, s. 231-244Artikel i tidskrift (Refereegranskat)
    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.

  • 5. Dupont, Chris L
    et al.
    Larsson, John
    Yooseph, Shibu
    Ininbergs, Karolina
    Goll, Johannes
    Asplund-Samuelsson, Johannes
    McCrow, John P
    Celepli, Narin
    Allen, Lisa Zeigler
    Ekman, Martin
    Lucas, Andrew J
    Hagström, Åke
    Thiagarajan, Mathangi
    Brindefalk, Björn
    Richter, Alexander R
    Andersson, Anders F
    Tenney, Aaron
    Lundin, Daniel
    Tovchigrechko, Andrey
    Nylander, Johan A A
    Naturhistoriska riksmuseet, Enheten för bioinformatik och genetik.
    Brami, Daniel
    Badger, Jonathan H
    Allen, Andrew E
    Rusch, Douglas B
    Hoffman, Jeff
    Norrby, Erling
    Friedman, Robert
    Pinhassi, Jarone
    Venter, J Craig
    Bergman, Birgitta
    Functional tradeoffs underpin salinity-driven divergence in microbial community composition.2014Ingår i: PloS one, ISSN 1932-6203, Vol. 9, nr 2, s. e89549-Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Bacterial community composition and functional potential change subtly across gradients in the surface ocean. In contrast, while there are significant phylogenetic divergences between communities from freshwater and marine habitats, the underlying mechanisms to this phylogenetic structuring yet remain unknown. We hypothesized that the functional potential of natural bacterial communities is linked to this striking divide between microbiomes. To test this hypothesis, metagenomic sequencing of microbial communities along a 1,800 km transect in the Baltic Sea area, encompassing a continuous natural salinity gradient from limnic to fully marine conditions, was explored. Multivariate statistical analyses showed that salinity is the main determinant of dramatic changes in microbial community composition, but also of large scale changes in core metabolic functions of bacteria. Strikingly, genetically and metabolically different pathways for key metabolic processes, such as respiration, biosynthesis of quinones and isoprenoids, glycolysis and osmolyte transport, were differentially abundant at high and low salinities. These shifts in functional capacities were observed at multiple taxonomic levels and within dominant bacterial phyla, while bacteria, such as SAR11, were able to adapt to the entire salinity gradient. We propose that the large differences in central metabolism required at high and low salinities dictate the striking divide between freshwater and marine microbiomes, and that the ability to inhabit different salinity regimes evolved early during bacterial phylogenetic differentiation. These findings significantly advance our understanding of microbial distributions and stress the need to incorporate salinity in future climate change models that predict increased levels of precipitation and a reduction in salinity.

  • 6.
    Hryniewicz, Krzysztof
    et al.
    Institute of Paleobiology, Polish Academy of Sciences, ul. Twarda 51/55, 00-818 Warszawa, Poland.
    Bitner, Maria Aleksandra
    Institute of Paleobiology, Polish Academy of Sciences, ul. Twarda 51/55, 00-818 Warszawa, Poland.
    Durska, Ewa
    Faculty of Geology, University of Warsaw, ul. Żwirki i Wigury 93, 02-089 Warszawa, Poland.
    Hagström, Jonas
    Naturhistoriska riksmuseet, Enheten för paleobiologi.
    Hjálmarsdóttir, Hanna Rósa
    The University Centre in Svalbard (UNIS), Pb 156, NO-9171 Longyearbyen, Norway.
    Jenkins, Robert G.
    School of Natural System, College of Science and Engineering, Kanazawa University, Kanazawa City, Ishikawa 920-1192, Japan.
    Little, Crispin T.S.
    School of Earth and Environment, University of Leeds, Leeds LS2 9JT, UK.
    Miyajima, Yusuke
    Department of Geology and Mineralogy, Graduate School of Science, Kyoto University, Oiwakecho, Kitashirakawa, Sakyo-ku, Kyoto 606-8502, Japan.
    Nakrem, Hans Arne
    Natural History Museum, University of Oslo, PO Box 1172 Blindern, NO-0318 Oslo, Norway.
    Kaim, Andrzej
    Institute of Paleobiology, Polish Academy of Sciences, ul. Twarda 51/55, 00-818 Warszawa, Poland.
    Paleocene methane seep and wood-fall marine environments from Spitsbergen, SvalbardManuskript (preprint) (Övrigt vetenskapligt)
    Abstract [en]

    A recently discovered Paleocene seep locality from Fossildalen onSpitsbergen,Svalbard,is described. This is one of a very few seep communities of the latest Cretaceous–earliest Palaeogene age, and the best preserved Paleocene seep community known so far. The seep 2 carbonates and associated fossils have been first identified in museum collections, and subsequently sampled in the field. The carbonates are exclusively ex-situand come fromtheoffshore siltstones of the Basilika Formation. Isotopically light composition (δ13C values approaching -50‰ V-PDB), and characteristic petrographic textures of the carbonates combined with the isotopically lightarchaeal lipid are consistent with the formation at fossil hydrocarbon seep. The invertebrate fauna associated with the carbonates is of moderate diversity (16 species) and has a shallow water affinity. It containsa species of the thyasirid genus Conchocele, common in other seeps of that age. The finding sheds new light onto the history of seepage on Svalbard, and onto the evolutionand ecologyof seep faunas during the latest Cretaceous–earliest Palaeogenetime interval.

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