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  • 201. Bouchal, Johannes M.
    et al.
    Dojen, C.
    Denk, Thomas
    Die Neubearbeitung der fossilen Flora von Leše/Liescha am Landesmuseum für Kärnten: vorläufige Mitteilung2017In: Carinthia II, Vol. 207, no 127, p. 395-400Article in journal (Refereed)
  • 202.
    Bouchal, Johannes M.
    et al.
    Swedish Museum of Natural History, Department of Paleobiology.
    Grímsson, F.
    Zetter, Reinhard
    Denk, Thomas
    Swedish Museum of Natural History, Department of Paleobiology.
    Some new pollen taxa from the middle Miocene of south western Anatolia2016Conference paper (Other academic)
    Abstract [en]

    In an ongoing study, focussing on the plant fossils and palynofloras of the lignite strip mines of the Yatağan basin(Muğla province), a number of pollen taxa, previously not reported from middle Miocene terrestrial sediments of Anatolia were encountered.

  • 203.
    Bouchal, Johannes M.
    et al.
    Swedish Museum of Natural History, Department of Paleobiology.
    Güner, Tuncay H.
    Swedish Museum of Natural History, Department of Paleobiology. Faculty of Forestry, Department of Forest Botany, Istanbul University Cerrahpa¸sa, 34473 Bahçeköy, Istanbul, Turkey.
    Denk, Thomas
    Swedish Museum of Natural History, Department of Paleobiology.
    Middle Miocene climate of southwestern Anatolia from multiple botanical proxies2018In: Climate of the Past Discussions, ISSN 1814-9340, E-ISSN 1814-9359, Vol. 14, p. 1427-1440Article in journal (Other academic)
    Abstract [en]

    The middle Miocene climate transition (MMCT) was a phase of global cooling possibly linked to decreasing levels of atmospheric CO2. The MMCT coincided with the European  Mammal Faunal Zone MN6. From this time, important biogeographic links between Anatolia  and eastern Africa include the hominid Kenyapithecus. Vertebrate fossils suggested mixed  open and forested landscapes under (sub)tropical seasonal climates for Anatolia. Here, we  infer the palaeoclimate during the MMCT and the succeeding cooling phase for a middle Miocene (14.8–13.2 Ma) of an intramontane basin in southwestern Anatolia using three2palaeobotanical proxies: (i) Köppen signatures based on the nearest-living-relative principle. (ii) Leaf physiognomy analysed with the Climate Leaf Analysis Multivariate Program (CLAMP). (iii) Genus-level biogeographic affinities of fossil floras with modern regions. The three proxies reject tropical climates for the MMCT of southwestern Anatolia and instead infer warm temperate C climates. Köppen signatures reject summer-dry Cs climates but cannot discriminate between fully humid Cf and winter-dry Cw; CLAMP reconstructs Cf climate based on the low X3.wet/X3.dry ratio. Additionally, we assess whether the palaeobotanical record does resolve transitions from the warm Miocene Climatic Optimum (MCO, 16.8–14.7 Ma) into the MMCT (14.7–13.9 Ma), and a more pronounced cooling at 13.9–13.8 Ma, as reconstructed from benthic stable isotope data. For southwestern Anatolia, we find that arboreal taxa predominate in MCO floras (MN5), whereas in MMCT floras (MN6) abundances of arboreal and non-arboreal elements strongly fluctuate indicating higher structural complexity of the vegetation. Our data show a distinct pollen zone between MN6 and MN7+8 dominated by herbaceous taxa. The boundary MN6 and MN7+8, roughly corresponding to a first abrupt cooling at 13.9–13.8 Ma, possibly might be associated with this herb-rich pollen zone.

  • 204.
    Bouchal, Johannes M.
    et al.
    Swedish Museum of Natural History, Department of Paleobiology.
    Güner, Tuncay H.
    Denk, Thomas
    Swedish Museum of Natural History, Department of Paleobiology.
    Palynological and palaeobotanical investigations in the Miocene Yatağan basin, Turkey: High-resoluton taxonomy and biostratigraphy2015Conference paper (Other academic)
    Abstract [en]

    The subject of this study is the palynology (biostratigraphic and taxonomic) and the plant remains of the lignite strip mines of Eskihisar, Salihpasalar, and Tinaz (Muğla province, western Turkey). In the Yatağan basin two Miocene to Pliocene formations are present, the Eskihisar Formation (early to middle Miocene) and the Yatağan Formation (late Miocene to early Pliocene). Both formations represent river and lake deposits consisting mainly of conglomerate, sandstone, claystone, limestone, tuffite, and intercalated lignite; the thickest, actively mined lignite seams occur in the Sekköy member of the Eskihisar Formation.

    Previous palynological studies of the palynoflora of the Yatağan basin mainly focussed on its biostratigraphic and palaeoclimatic significance, using conventional morphological nomenclature and light microscopy (LM).

    In this study the „single grain method“ is applied. Using this method, the same individual pollen grains are investigated by using both LM and scanning electron microscopy (SEM). The resulting high-resolution pictographs enable a much higher taxonomic resolution.

     

    The studied palynoflora is very rich and taxonomically diverse. Cryptogams are represented by more than ten spore morphotypes of at least three families (Osmundaceae, Pteridaceae, Polypodiaceae). Gymnosperm pollen is dominated by Cupressaceae, Gnetales (Ephedra), and Pinaceae (Cathaya, Keteleeria, Pinus). Angiosperm pollen can be assigned to 57 different genera belonging to Poaceae, Typhaceae, Altingiaceae, Amaranthaceae (Chenopodieae), Anacardiaceae, Apiaceae (three types), Asteraceae (Asteroideae, Cichoriodeae), Betulaceae (Alnus, Betula, Carpinus, Ostrya) Buxaceae, Campanulaceae, Caprifoliaceae (Lonicera), Caryophyllaceae, Dipsacaceae, Eucommiaceae, Euphorbiaceae, Fabaceae, Fagaceae (Fagus, Quercus, Trigonobalanopsis) Geraniaceae, Juglandaceae, Linnaceae (Linnum), Malvaceae, Myricaceae, Nymphaeaceae, Oleaceae (four different types), Plumbaginaceae (Armeria,), Polygonaceae (Rumex), Rosaceae, Sapindaceae (Acer), Ulmaceae (Cedrelospermum, Ulmus, Zelkova), and Zingiberales (Spirematospermum).

     

    In addition, more than two thousand plant macrofossils were collected in the course of repeated field trips, including remains of Pinaceae, Berberidiaceae (Mahonia), Betulaceae (Alnus, Carpinus), Buxaceae (Buxus), Fagaceae (Fagus, Quercus), Lauraceae, Malvaceae (Tilia), Myricaceae (Myrica), Rosaceae, Salicaceae (Populus, Salix), Sapindaceae (Acer), Smilacaceae (Smilax), Typhaceae (Typha), Ulmaceae (Zelkova).

     

    A combined analysis integrating these rich and diverse plant macro- and microfossil records will lead to a better understanding and refined reconstruction of the vegetation in the Yatağan basin during the middle to late Miocene.

  • 205. Bouchal, Johannes, M.
    et al.
    Mayda, S.
    Akgün, F.
    Grímsson, F.
    Zetter, R.
    Denk, Thomas
    Miocene palynofloras of the Tınaz lignite mine, Muğla, southwest Anatolia: taxonomy, palaeoecology and local vegetation change2017In: Review of Palaeobotany and Palynology, ISSN 0034-6667, E-ISSN 1879-0615, Vol. 243, p. 1-36Article in journal (Refereed)
  • 206.
    Bouchal, Johannes M.
    et al.
    Swedish Museum of Natural History, Department of Paleobiology.
    Mayda, Serdar
    Natural History Museum, Ege University, 35100 Izmir, Turkey.
    Zetter, Reinhard
    University of Vienna, Department of Palaeontology, Vienna, Austria.
    Grímsson, Fridgeir
    University of Vienna, Department of Palaeontology, Vienna, Austria.
    Akgün, Funda
    Dokuz Eylül University, Department of General Geology, 35210 Izmir, Turkey.
    Denk, Thomas
    Swedish Museum of Natural History, Department of Paleobiology.
    Miocene palynofloras of the Tınaz lignite mine, Muğla, southwest Anatolia: taxonomy, palaeoecology and local vegetation change2017In: Review of Palaeobotany and Palynology, ISSN 0034-6667, E-ISSN 1879-0615, Vol. 243, p. 1-36Article in journal (Refereed)
    Abstract [en]

    Middle Miocene deposits exposed at the Tınaz lignite mine, Yatağan Basin, Muğla, southwestern Turkey, were palynologically investigated. The Tınaz lignite mine section belongs to the Eskihisar Formation. The lignite seam at the base of the section represents the uppermost part of the Turgut Member. Above, c. 65 m of clayey siltstone, limestone, and marls represent the Sekköy Member. Nine spores, zygospores and cysts of fungi and algae, seven moss and fern spores, 12 gymnosperm pollen types, and more than 80 angiosperm pollen taxa were recovered from the Tınaz lignite mine section. Three pollen zones were recognized, of which pollen zone 1 corresponds to the formation of the main lignite seam and reflects the change from a fluviatile to a lacustrine depositional setting. Pollen zones 2 and 3 and a transitional zone 2-3 reflect different stages of lake development and a shift in local vegetation from forested (pollen zones 1 and 2) to more open (transitional zone 2-3, zone 3). Interpreting changes in regional vegetation from pollen zones 1 to 3 is not straightforward as changes in the pollen spectra may be affected by changing contributions of airborne and water transported pollen and spores to the observed palynoassemblages. Age inference for the Tınaz lignite mine section has been complicated by the absence of datable ash layers, associated mammal faunas, or marine sediments. However, pollen zone 3 shares key features with the pollen spectrum recovered from the nearby mammal site Yenieskihisar (upper part of Sekköy Member) for which an age of 12.5-11.2 Ma has been suggested, and to the youngest pollen zone recovered from the mammal locality Çatakbağyaka, 10 km south of Tınaz, that probably represents mammal zone MN7/8 instead of MN5 or MN6 as previously suggested. In contrast, pollen zones 1 and 2 are fairly similar to the basal parts of the Çatakbağyaka pollen flora (uppermost parts of Turgut Member, basalmost parts of Sekköy Member). Furthermore, new mammal data from the Yatağan basin suggest that the layers below pollen zone 1 are MN4/5, and that carnivores cooccuring with pollen zone 1 in the main lignite seam of Eskihisar probably belong to MN6. Hence, a Langhian to Serravallian age can be inferred for pollen zones 1 and 2 of the Tınaz lignite mine section, and a late Serravallian age for pollen zone 3. Palaeobiogeographic relationships of the palynofloras are generally northern hemispheric, with many north temperate tree taxa showing modern disjunctions East Asia- NorthAmerica (Tsuga, Carya), East Asia- western Eurasia (Zelkova), East Asia- North America- western Eurasia (Liquidambar), or restricted to East Asia (Cathaya, Eucommia) or North America (Decodon). A few taxa belong to extinct lineages that have complex biogeographic patterns (Engelhardioideae, Cedrelospermum). The presence of Picrasma (Simaroubaceae) in the lower lignite layers of pollen zone 1 is remarkable, as the botanical affinities with the enigmatic flower Chaneya present in early to middle Miocene deposits of Turkey and Central Europe have recently been shown to be with Picrasma

  • 207.
    Bouchal, Johannes Martin
    Swedish Museum of Natural History, Department of Paleobiology. University of Vienna.
    EVOLUTIONARY TRENDS AND ECOLOGICAL DIFFERENTIATION IN EARLY CENOZOIC FAGACEAE OF WESTERN NORTH AMERICA2014In: American Journal of Botany, ISSN ISSN: 0002-9122., Vol. 101, no 8, p. 1332-1349Article in journal (Refereed)
    Abstract [en]

    • Premise of the study: The early Cenozoic was a key period of evolutionary radiation in Fagaceae. The common notion is that

    species thriving in the modern summer-dry climate of California originated in climates with ample summer rain during the

    Paleogene.

    • Methods: We investigated in situ and dispersed pollen of Fagaceae from the uppermost Eocene Florissant fossil beds, Colorado,

    United States, using a combined light and scanning electron microscopy approach.

    • Key results: Pollen types of Castaneoideae with affi nities to modern Castanea , Lithocarpus , and Castanopsis were recognized.

    Pollen of the extinct genus Fagopsis represents a derived type of Castaneoideae pollen. Infrageneric groups of Quercus were

    well represented, including pollen of Group Protobalanus. The taxonomic diversity of Fagaceae and of the total plant assemblage

    indicates a mosaic of microclimates, that range from pronounced to weakly seasonal climates and depend on slope aspect

    and elevation. Continental climatic conditions may have triggered the evolution of sclerophyllous leaves and adaptive radiation

    in Quercus and other taxa thriving today under distinctly summer-dry and winter-dry climates.

    • Conclusions: Vegetation types similar to modern vegetation belts of the Coastal Ranges (chaparral, nemoral conifer forest)

    were established in the Front Range in the late Eocene. Coeval plant assemblages from the Coastal Ranges of California indicate

    distinctly subtropical, moist climates. Hence, characteristic elements found today in the summer-dry and winter-dry climates

    of Pacifi c North America ( Quercus Group Protobalanus, Notholithocarpus ) may opportunistically have dispersed into

    their modern ranges later in the Cenozoic. This scenario is in contrast to the evolution and migration patterns of their western

    Eurasian Mediterranean counterparts ( Quercus Group Ilex).

  • 208. Bouvier, Laura
    et al.
    Costa, Maria
    Connelly, James
    Jensen, Ninna
    Wielandt, Daniel
    Storey, Michael
    Nemchin, Alexander
    Whitehouse, Martin
    Swedish Museum of Natural History, Department of Geology.
    Snape, Joshua
    Swedish Museum of Natural History, Department of Geology.
    Bellucci, Jeremy
    Swedish Museum of Natural History, Department of Geology.
    Moynier, Frederic
    Agranier, Arnaud
    Gueguen, Bleuenn
    Schonbachler, Maria
    Bizzarro, Martin
    Evidence for extremely rapid magma ocean crystallization and crust formation on Mars2018In: Nature, ISSN 1476-4687, Vol. 558, p. 586-589Article in journal (Refereed)
    Abstract [en]

    The formation of a primordial crust is a critical step in the evolution of terrestrial planets but the timing of this process is poorly understood. The mineral zircon is a powerful tool for constraining crust formation because it can be accurately dated with the uranium-to-lead (U–Pb) isotopic decay system and is resistant to subsequent alteration. Moreover, given the high concentration of hafnium in zircon, the lutetium-to-hafnium (176Lu–176Hf) isotopic decay system can be used to determine the nature and formation timescale of its source reservoir (1,2,3) Ancient igneous zircons with crystallization ages of around 4,430 million years (Myr) have been reported in Martian meteorites that are believed to represent regolith breccias from the southern highlands of Mars (4,5) These zircons are present in evolved lithologies interpreted to reflect re-melted primary Martian crust4, thereby potentially providing insight into early crustal evolution on Mars. Here, we report concomitant high-precision U–Pb ages and Hf-isotope compositions of ancient zircons from the NWA 7034 Martian regolith breccia. Seven zircons with mostly concordant U–Pb ages define 207Pb/206Pb dates ranging from 4,476.3 ± 0.9 Myr ago to 4,429.7 ± 1.0 Myr ago, including the oldest directly dated material from Mars. All zircons record unradiogenic initial Hf-isotope compositions inherited from an enriched, andesitic-like crust extracted from a primitive mantle no later than 4,547 Myr ago. Thus, a primordial crust existed on Mars by this time and survived for around 100 Myr before it was reworked, possibly by impacts (4,5) to produce magmas from which the zircons crystallized. Given that formation of a stable primordial crust is the end product of planetary differentiation, our data require that the accretion, core formation and magma ocean crystallization on Mars were completed less than 20 Myr after the formation of the Solar System. These timescales support models that suggest extremely rapid magma ocean crystallization leading to a gravitationally unstable stratified mantle, which subsequently overturns, resulting in decompression melting of rising cumulates and production of a primordial basaltic to andesitic crust (6,7).

  • 209. Brace, Selina
    et al.
    Palkopoulou, Eleftheria
    Dalen, Love
    Lister, Adrian M.
    Miller, Rebecca
    Otte, Marcel
    Germonpre, Mietje
    Blockley, Simon P. E.
    Stewart, John R.
    Barnes, Ian
    Serial population extinctions in a small mammal indicate Late Pleistocene ecosystem instability2012In: Proceedings of the National Academy of Sciences of the United States of America, ISSN 0027-8424, E-ISSN 1091-6490, Vol. 109, no 50, p. 20532-20536Article in journal (Refereed)
  • 210. Brace, Selina
    et al.
    Thomas, Jessica A.
    Dalén, Love
    Swedish Museum of Natural History, Department of Bioinformatics and Genetics.
    Burger, Joachim
    MacPhee, Ross D. E.
    Barnes, Ian
    Turvey, Samuel T.
    Evolutionary History of the Nesophontidae, the Last Unplaced Recent Mammal Family2016In: Molecular biology and evolution, ISSN 0737-4038, E-ISSN 1537-1719, Vol. 33, no 12, p. 3095-3103Article in journal (Refereed)
    Abstract [en]

    The mammalian evolutionary tree has lost several major clades through recent human-caused extinctions. This process of historical biodiversity loss has particularly affected tropical island regions such as the Caribbean, an area of great evolutionary diversification but poor molecular preservation. The most enigmatic of the recently extinct endemic Caribbean mammals are the Nesophontidae, a family of morphologically plesiomorphic lipotyphlan insectivores with no consensus on their evolutionary affinities, and which constitute the only major recent mammal clade to lack any molecular information on their phylogenetic placement. Here, we use a palaeogenomic approach to place Nesophontidae within the phylogeny of recent Lipotyphla. We recovered the near-complete mitochondrial genome and sequences for 17 nuclear genes from a similar to 750-year-old Hispaniolan Nesophontes specimen, and identify a divergence from their closest living relatives, the Solenodontidae, more than 40 million years ago. Nesophontidae is thus an older distinct lineage than many extant mammalian orders, highlighting not only the role of island systems as "museums" of diversity that preserve ancient lineages, but also the major human-caused loss of evolutionary history.

  • 211. Brantberg, Krister
    et al.
    Babak, F.
    Kalthoff, Daniela
    Swedish Museum of Natural History, Department of Zoology.
    Do extant elephants have superior canal dehiscence syndrome?2015In: Acta Oto-Laryngologica, ISSN 0001-6489, E-ISSN 1651-2251Article in journal (Refereed)
  • 212. Brazilian Flora Group, The
    et al.
    Santos, Karin
    Swedish Museum of Natural History, Department of Botany.
    Brazilian Flora 2020: Innovation and collaboration to meet Target 1 of the Global Strategy for Plant Conservation (GSPC).: Brazilian Flora 20202018In: Rodriguésia, ISSN 0370-6583, Vol. 69, no 4, p. 1513-1527Article in journal (Refereed)
    Abstract [en]

    The Global Strategy for Plant Conservation (GSPC) was established by the Conference of Parties in 2002 todecrease the loss of plant diversity, reduce poverty and contribute to sustainable development. To achieve thisoverarching goal, the GSPC has established a series of targets, one of which is to ensure that plant diversity iswell understood, so that it can be effectively conserved and used in a sustainable manner. Brazil hosts morethan 46,000 species of plants, algae and fungi, representing one of the most biodiverse countries on Earth, andplaying a key role in the GSPC. To meet the GSPC goals of Target 1 and facilitate access to plant diversity,Brazil committed to preparing the List of Species of the Brazilian Flora (2008–2015) and the Brazilian Flora2020 (2016–present). Managing all the information associated with such great biodiversity has proven to be anextremely challenging task. Here, we synthesize the history of these projects, focusing on the multidisciplinaryand collaborative approach adopted to develop and manage the inclusion of all the knowledge generated thoughdigital information systems. We further describe the methods used, challenges faced, and strategies adopted, aswell as summarize advances to date and prospects for completing the Brazilian flora in 2020.Key words: database, diversity, hotspots, taxonomy.

  • 213. Brengman, L.
    et al.
    Fedo, C.M.
    Whitehouse, Martin J.
    Swedish Museum of Natural History, Department of Geology.
    Micro-scale silicon isotope heterogeneity observed in hydrothermal quartz precipitates from the >3.7 Ga Isua Greenstone Belt, SW Greenland.2016In: Terra Nova, ISSN 0954-4879, E-ISSN 1365-3121, Vol. 28, p. 70-75Article in journal (Refereed)
    Abstract [en]

    Pillow basalt and chert form integral lithologies comprising many Archean greenstone belt packages. To investigate details of these lithologies in the >3.7 Ga Isua Greenstone Belt, SW Greenland, we measured silicon isotope compositions of quartz crystals, by secondary ion mass spectrometry, from a quartz-cemented, quartz-amygdaloidal basaltic pillow breccia, recrystallized chert and chert clasts thought to represent silica precipitation under hydrothermal conditions. The recrystallized chert, chert clasts and quartz cement have overlapping δ30Si values, while the δ30Si values of the quartz amygdules span nearly the entire range of previously published values for quartz precipitates of any age, despite amphibolite facies metamorphism. We suggest that the heterogeneity is derived from kinetic isotope fractionation during quartz precipitation under disequilibrium conditions in a hydrothermal setting, consistent with the pillow breccia origin. On the basis of the present data, we conclude that the geological context of each sample must be carefully evaluated when interpreting δ30Si values of quartz.

  • 214.
    Britzke, Ricardo
    et al.
    Universidade Estadual Paulista.
    Oliveira, Claudio
    Universidade Estadual Paulista.
    Kullander, Sven
    Swedish Museum of Natural History, Department of Zoology.
    Apistogramma ortegai (Teleostei: Cichlidae), a new species of cichlid fish from the Ampyiacu River in the Peruvian Amazon basin2014In: Zootaxa, ISSN 1175-5326, E-ISSN 1175-5334, Vol. 3869, no 4, p. 409-419Article in journal (Refereed)
    Abstract [en]

    Apistogramma ortegai, new species, is described from small streams tributaries of the Ampiyacu River near Pebas, in easternPeru. It belongs to the Apistogramma regani species group and is distinguished from all other species of Apistogrammaby the combination of contiguous caudal spot to bar 7, presence of abdominal stripes, short dorsal-fin lappets in both sexes,absence of vertical stripes on the caudal fin, and reduced number of predorsal and prepelvic scales.

  • 215. Broushaki, Farnaz
    et al.
    Thomas, Mark G
    Link, Vivian
    López, Saioa
    van Dorp, Lucy
    Kirsanow, Karola
    Hofmanová, Zuzana
    Diekmann, Yoan
    Cassidy, Lara M
    Díez-del-Molino, David
    Kousathanas, Athanasios
    Sell, Christian
    Robson, Harry K
    Martiniano, Rui
    Blöcher, Jens
    Scheu, Amelie
    Kreutzer, Susanne
    Bollongino, Ruth
    Bobo, Dean
    Davoudi, Hossein
    Munoz, Olivia
    Currat, Mathias
    Abdi, Kamyar
    Biglari, Fereidoun
    Craig, Oliver E
    Bradley, Daniel G
    Shennan, Stephen
    Veeramah, Krishna R
    Mashkour, Marjan
    Wegmann, Daniel
    Hellenthal, Garrett
    Burger, Joachim
    Early Neolithic genomes from the eastern Fertile Crescent.2016In: Science, ISSN 0036-8075, E-ISSN 1095-9203, Vol. 353, no 6298Article in journal (Refereed)
    Abstract [en]

    We sequenced Early Neolithic genomes from the Zagros region of Iran (eastern Fertile Crescent), where some of the earliest evidence for farming is found, and identify a previously uncharacterized population that is neither ancestral to the first European farmers nor has contributed substantially to the ancestry of modern Europeans. These people are estimated to have separated from Early Neolithic farmers in Anatolia some 46,000 to 77,000 years ago and show affinities to modern-day Pakistani and Afghan populations, but particularly to Iranian Zoroastrians. We conclude that multiple, genetically differentiated hunter-gatherer populations adopted farming in southwestern Asia, that components of pre-Neolithic population structure were preserved as farming spread into neighboring regions, and that the Zagros region was the cradle of eastward expansion.

  • 216.
    Bruschini, Enrico
    et al.
    Sapienza Università di Roma.
    Speziale, Sergio
    Geoforschungszentrum, Potsdam.
    Andreozzi, Giovanni
    Sapienza Università di Roma.
    Bosi, Ferdinando
    Sapienza Università di Roma.
    Hålenius, Ulf
    Swedish Museum of Natural History, Department of Geology.
    The elasticity of MgAl2O4-MnAl2O4 spinels by Brillouin scattering and an empirical approach for bulk modulus prediction2015In: American Mineralogist, ISSN 0003-004X, E-ISSN 1945-3027, Vol. 100, p. 644-651Article in journal (Refereed)
  • 217. Buchbender, Volker
    et al.
    Hespanhol, Helena
    Krug, Michael
    Sérgio, Cecília
    Séneca, Ana
    Maul, Karola
    Hedenäs, Lars
    Swedish Museum of Natural History, Department of Botany.
    Quandt, Dietmar
    Phylogenetic reconstructions of the Hedwigiaceae reveal cryptic speciation and hybridisation in Hedwigia2014In: Bryophyte Diversity and Evolution, ISSN 2381-9677, Vol. 36, p. 1-21Article in journal (Refereed)
  • 218. Budd, D.A.
    et al.
    Troll, V.R.
    Deegan, F.M.
    Jolis, E.M.
    Smith, V.C.
    Whitehouse, Martin J.
    Swedish Museum of Natural History, Department of Geology.
    Harris, C.
    Freda, C.
    Hilton, D.R.
    Halldorsson, S.A.
    Bindemann, I.N.
    Magma reservoir dynamics at Toba caldera, Indonesia, recorded by oxygen isotope zoning in quartz2017In: Scientific Reports, ISSN 2045-2322, E-ISSN 2045-2322, Vol. 7, article id 40624Article in journal (Refereed)
    Abstract [sv]

    Quartz is a common phase in high-silica igneous rocks and is resistant to post-eruptive alteration, thus offering a reliable record of magmatic processes in silicic magma systems. Here we employ the 75 ka Toba super-eruption as a case study to show that quartz can resolve late-stage temporal changes in magmatic δ18O values. Overall, Toba quartz crystals exhibit comparatively high δ18O values, up to 10.2‰, due to magma residence within, and assimilation of, local granite basement. However, some 40% of the analysed quartz crystals display a decrease in δ18O values in outermost growth zones compared to their cores, with values as low as 6.7‰ (maximum ∆core−rim = 1.8‰). These lower values are consistent with the limited zircon record available for Toba, and the crystallisation history of Toba quartz traces an influx of a low-δ18O component into the magma reservoir just prior to eruption. Here we argue that this late-stage low-δ18O component is derived from hydrothermally-altered roof material. Our study demonstrates that quartz isotope stratigraphy can resolve magmatic events that may remain undetected by whole-rock or zircon isotope studies, and that assimilation of altered roof material may represent a viable eruption trigger in large Toba-style magmatic systems.

  • 219. Buffington, Matthew L
    et al.
    Forshage, Mattias
    Swedish Museum of Natural History, Department of Zoology.
    Redescription of Ganaspis brasiliensis (Ihering, 1905), new combiantion, (Hymenoptera: Figitidae) a natural enemy of the invasive Drosophila suzukii (Matsumura, 1931) (Diptera: Drosophilidae)2016In: Proceedings of the Entomological Society of Washington, ISSN 0013-8797, Vol. 118, no 1, p. 1-13Article in journal (Refereed)
    Abstract [en]

    The new combination of Ganaspis brasiliensis (Ihering, 1905) is proposed, and the species is redescribed from historical specimens taken in the Neotropical Region as well as more recent specimens reared from Drosophila suzukii Matsumura, 1931 in South Korea. Drosophila suzukii, otherwise known as the spotted-wing Drosophila, is a major pest of soft fruits the world over, and the search for effective natural enemies of this fly are ongoing. Though not parasitoids of D. suzukii, we also propose the following new combinations: Dieucoila brasiliensis (Kieffer, 1909), new combination, and Dieucoila brasiliana (Weld, 1952), new combination. After summarizing all known species of Eucoilinae with the specific epithet ‘brasiliensis’, we encourage future researchers to avoid this name in order prevent nomenclatural confusion.

  • 220. Buffington, Matthew L
    et al.
    Forshage, Mattias
    Swedish Museum of Natural History, Department of Zoology.
    The description of Garudella Buffington and Forshage, new genus (Hymenoptera: Figitidae: Eucoilinae)2014In: Proceedings of the Entomological Society of Washington, ISSN 0013-8797, Vol. 116, no 3, p. 225-242Article in journal (Refereed)
    Abstract [en]

    Garudella, a remarkable new genus of eucoiline wasp is described from Thailand, Laos, and the Republic of Congo. Four new species of Garudella are described as well: G. acothonaspis, G. afrotropica, G. algo, and G. alicae. Several autapomorphies distinguish this genus from other eucoiline genera: a distinctly protracted and broadened pronotal plate; a massive, posteriorly protruding prop- odeum; reduced posterior rim of metapleuron; reduced scutellar foveae and lack of lateral bar “windows”; and a generally reduced scutellar plate. In addition, the posterior of the head has a distinctly curved occipital impression, resulting in the cuticle surrounding the foramen magnum to be extruded into a neck-like process. The biology of Garudella is unknown, but based on phylogenetic inference from morphology, the presumed host could be a cyclorrhaphous Diptera in a saprophagous environment.

  • 221. Buffington, Matthew L
    et al.
    Gallardo, Fabiana E
    Reche, Vanina
    Forshage, Mattias
    Swedish Museum of Natural History, Department of Zoology.
    A Revision of Zaeucoila Ashmead (Hymenoptera, Figitidae), Parasitoids of Agromyzidae (Diptera): New Species, Identity, Distribution, and Hosts2017In: Proceedings of the Entomological Society of Washington, ISSN 0013-8797, Vol. 119, no 3, p. 317-397Article in journal (Refereed)
    Abstract [en]

    The eucoiline genus Zaeucoila Ashmead is revised. Following a re- evaluation combining previously published phylogenetic data and new specimens, Agrostocynips D ́ıaz is synonymized with Zaeucoila. All species included in Zaeucoila are systematically treated, and now amounts to twelve, seven of which are described as new here: Zaeucoila bitiburculata new species, Z. fidalgoii new species, Z. infuscata new species, Z. johnsonii new species, Z. lignys new species, Z. normae new species, Z. patera new species. The following new combinations are proposed and species redescribed: Zaeucoila grenadensis (Ashmead), new combination; Z. robusta (Ashmead), new combination; Z. flavipes (Ashmead), new combination. Agrostocynips diastrophi (Ashmead), Agrostocynips clavatus D ́ıaz, and Agrostocynips enneatoma (D ́ıaz) are new synonyms of Zaeucoila robusta. Zaeucoila incompleta (Kieffer), Z. triangu- lifera Kieffer, and Z. unicarinata Ashmead are redescribed. Zaeucoila is an unusual genus of Zaeucoilini in its wide distribution area: it can be found from southern Argentina well into the eastern United States and southern Canada; no other zaeucoiline genus shows such a pattern. Host records and geographic data for Zaeucoila are brought up to date, as well as a key to species. Zeucoila are primary parasitoids of Agromyzidae, including Liriomyza trifolii and other species that are notable economic pests of agriculture. Tropideucoila fulvonotata (Kieffer) is transferred to Marthiella (new combination).

  • 222.
    Bukontaite, Rasa
    et al.
    Swedish Museum of Natural History, Department of Zoology. Stockholm University.
    Miller, Kelly
    University of New Mexico.
    Bergsten, Johannes
    Swedish Museum of Natural History, Department of Zoology.
    The utility of CAD in recovering Gondwanan vicariance events and the evolutionary history of Aciliini (Coleoptera: Dytiscidae).2014In: BMC Evolutionary Biology, ISSN 1471-2148, E-ISSN 1471-2148, Vol. 14, no 5, p. 1-18Article in journal (Refereed)
    Abstract [en]

    Background

    Aciliini presently includes 69 species of medium-sized water beetles distributed on all continents except Antarctica. The pattern of distribution with several genera confined to different continents of the Southern Hemisphere raises the yet untested hypothesis of a Gondwana vicariance origin. The monophyly of Aciliini has been questioned with regard to Eretini, and there are competing hypotheses about the intergeneric relationship in the tribe. This study is the first comprehensive phylogenetic analysis focused on the tribe Aciliini and it is based on eight gene fragments. The aims of the present study are: 1) to test the monophyly of Aciliini and clarify the position of the tribe Eretini and to resolve the relationship among genera within Aciliini, 2) to calibrate the divergence times within Aciliini and test different biogeographical scenarios, and 3) to evaluate the utility of the gene CAD for phylogenetic analysis in Dytiscidae.

    Results

    Our analyses confirm monophyly of Aciliini with Eretini as its sister group. Each of six genera which have multiple species are also supported as monophyletic. The origin of the tribe is firmly based in the Southern Hemisphere with the arrangement of Neotropical and Afrotropical taxa as the most basal clades suggesting a Gondwana vicariance origin. However, the uncertainty as to whether a fossil can be used as a stem-or crowngroup calibration point for Acilius influenced the result: as crowngroup calibration, the 95% HPD interval for the basal nodes included the geological age estimate for the Gondwana break-up, but as a stem group calibration the basal nodes were too young. Our study suggests CAD to be the most informative marker between 15 and 50 Ma. Notably, the 2000 bp CAD fragment analyzed alone fully resolved the tree with high support.

    Conclusions

    1) Molecular data confirmed Aciliini as a monophyletic group. 2) Bayesian optimizations of the biogeographical history are consistent with an influence of Gondwana break-up history, but were dependent on the calibration method. 3) The evaluation using a method of phylogenetic signal per base pair indicated Wnt and CAD as the most informative of our sampled genes.

  • 223. BUONO, Monica
    et al.
    FERNANDEZ, Martha
    REGUERO, Marcelo
    MARENSSI, Sergio
    SANTILLANA, Sergio
    Mörs, Thomas
    Swedish Museum of Natural History, Department of Paleobiology.
    Eocene basilosaurid whales from the La Meseta Formation, Marambio (Seymour) Island, Antarctica2016In: Ameghiniana, ISSN 0002-7014, E-ISSN 1851-8044, Vol. 53, no 3, p. 296-315Article in journal (Refereed)
    Abstract [en]

    Basal fully aquatic whales, the basilosaurids are worldwide known from Bartonian–Priabonian localities, indicating that this group was widely distributed during the late middle Eocene. In the Northern Hemisphere, fossils of basilosaurids are abundant, while records in the Southern Hemisphere are scarce and, in some cases (i.e., Antarctica), doubtful. The presence of basilosaurids in Antarctica was, until now, uncertain because most of the records are based on fragmentary materials that preclude an accurate assignment to known archaeocete taxa. Here we report the findings of mandibles, teeth, and innominate bone remains of basilosaurids recovered from the La Meseta Formation (TELM 4 Lutetian–Bartonian and; TELM 7 Priabonian), in Marambio (Seymour) Island (James Ross Basin, Antarctic Peninsula). These findings confirm the presence of Basilosauridae in the marine realm of Antarctica, increasing our knowledge of the paleobiogeographic distribution of basilosaurids during the middle–late Eocene. In addition, one of these records is among the oldest occurrences of basilosaurids worldwide, indicating a rapid radiation and dispersal of this group since at least the early middle Eocene.

  • 224. Butler, Aodhán
    et al.
    Cunningham, John
    Swedish Museum of Natural History, Department of Paleobiology.
    Budd, Graham
    Donoghue, Philip
    Experimental taphonomy of Artemia reveals the role of endogenous microbes in mediating decay and fossilization2015In: Proceedings of the Royal Society of London. Biological Sciences, ISSN 0962-8452, E-ISSN 1471-2954, Vol. 282, p. 20150476-Article in journal (Refereed)
    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.

  • 225.
    Bäcklin, Britt-Marie
    et al.
    Swedish Museum of Natural History, Department of Environmental research and monitoring.
    Moraeus, Charlotta
    Swedish Museum of Natural History, Department of Environmental research and monitoring.
    Strömberg, Annika
    Swedish Museum of Natural History, Department of Environmental research and monitoring.
    Karlsson, Olle
    Swedish Museum of Natural History, Department of Environmental research and monitoring.
    Härkönen, Tero
    Swedish Museum of Natural History, Department of Environmental research and monitoring.
    Sälpopulationer och sälhälsa2016In: HAVET 2015/2016: Om miljötillståndet i svenska havsområden / [ed] Havsmiljöinstitutet, Havsmiljöinstitutet , 2016, p. 116-118Chapter in book (Other academic)
  • 226.
    Bäcklin, Britt-Marie
    et al.
    Swedish Museum of Natural History, Department of Environmental research and monitoring.
    Moraeus, Charlotta
    Swedish Museum of Natural History, Department of Environmental research and monitoring.
    Strömberg, Annika
    Swedish Museum of Natural History, Department of Environmental research and monitoring.
    Stenström, Malin
    Swedish Museum of Natural History, Department of Environmental research and monitoring.
    Neimanis, Aleksija
    Swedish Museum of Natural History, Department of Environmental research and monitoring. SVA.
    Undersökning av insamlade sälar från Östersjön 2013/20142015Report (Other academic)
  • 227.
    Bäcklin, Britt-Marie
    et al.
    Swedish Museum of Natural History, Department of Environmental research and monitoring.
    Strömberg, Annika
    Swedish Museum of Natural History, Department of Environmental research and monitoring.
    Moraeus, Charlotta
    Härkönen, Tero
    Swedish Museum of Natural History, Department of Environmental research and monitoring.
    Karlsson, Olle
    Swedish Museum of Natural History, Department of Environmental research and monitoring.
    Undersökning av sälar insamlade 20152017Report (Other academic)
    Abstract [en]

    Since the 1970s, grey seals (Halichoerus grypus), harbour seals (Phoca vitulina) and ringed seals (Phoca hispida) have been collected and necropsied at the Swedish Museum of Natural History. Mostly have grey seals been examined. The effect of hunting during 19th century and reproductive failure during the latter half of the century decreased Baltic seal populations. In the 1970s and 1980s, pathological changes found mostly in grey seals was called the Baltic Seal Disease Complex and was thought to be related to high levels of PCB and DDT. Since then several pathological changes have decreased in prevalence as well as levels of PCB and DDT. Since then in grey seals, the prevalence of intestinal ulcers has increased and then decreased, blubber thickness has decreased and the prevalence of a zoonotic biliary trematode infection increased.

    In 2015, whole bodies and samples from 137 grey seals, 44 harbour seals and 27 ringed seals were examined at the museum. The public reported 196 seals found dead along the Swedish coast. At present, the Baltic grey seal population increases with 8% each year and 85% of the examined females 6-24 years old were pregnant during the pregnant period (August-February) in 2015. The harbour seal populations presently increase with 7-9 % per year, although the numbers of examined harbour seals are much lower than the number of grey seals, the proportion of examined pregnant harbour seals in corresponding age group was only 57%. The ringed seal population in the Gulf of Bothnia presently increase with 4,5% per year. One mature female examined from the period of pregnancy was pregnant. Of the examined 27 ringed seals, 20 of them were younger than 4 years. Two two-year old females showed malformations as diaphragmatic hiatus in one of them and the other female lacked one of the uterine horns.

     

    In conclusion, the health situation for examined Baltic grey seals is better and the increase in the population during the last 15 years is stable. The number of examined harbour seals and ringed seals is small for presenting trends but harbour seals showed a tendency to low pregnancy rate that needs further studies. The populations of harbour seals on the Swedish west coast were affected by epidemics in 1988, 2002 and 2014 and the development rate of these populations have decreased since 2002. The development of the harbour seal population on the Swedish east coast has a steady increase since the 1970s. The population of ringed seals has a low increase in the Gulf of Bothnia

  • 228. Büdel, B.
    et al.
    Colesie, C.
    Green, T.G.A.
    Grube, Martin
    Lázaro Suau, R.
    Loewen-Schneider, K.
    Maier, S.
    Peer, T.
    Pintado, A.
    Raggio, J.
    Ruprecht, U.
    Sancho, L. G.
    Schroeter, B.
    Türk, R.
    Weber, B.
    Wedin, Mats
    Swedish Museum of Natural History, Department of Botany.
    Westberg, Martin
    Swedish Museum of Natural History, Department of Botany.
    Williams, L.
    Zheng, L.
    Improved appreciation of the functioning and importance of biological soil crusts in Europe – the Soil Crust International project (SCIN)2014In: Biodiversity and Conservation, ISSN 0960-3115, E-ISSN 1572-9710, Vol. 23, p. 1639-1658Article in journal (Refereed)
  • 229. Cabral, R.A.
    et al.
    Jackson, M.G.
    Koga, K.T.
    Rose-Koga, E.F.
    Hauri, E.H.
    Whitehouse, Martin J.
    Swedish Museum of Natural History, Department of Geology.
    Price, A.A:
    Day, J.M.D.
    Shimizu, N.
    Kelley, K.A.
    Volatile cycling of H2O, CO2, F, and Cl in the HIMU mantle: A new window provided by melt inclusions from oceanic hotspot lavas at Mangaia, Cook Islands.2014In: Geochemistry, Geophysics, Geosystems, ISSN 1525-2027, Vol. 15, p. 4445-4467Article in journal (Refereed)
    Abstract [en]

    Mangaia hosts the most radiogenic Pb-isotopic compositions observed in ocean island basalts and represents the HIMU (high µ = 238U/204Pb) mantle end-member, thought to result from recycled oceanic crust. Complete geochemical characterization of the HIMU mantle end-member has been inhibited due to a lack of deep submarine glass samples from HIMU localities. We homogenized olivine-hosted melt inclusions separated from Mangaia lavas and the resulting glassy inclusions made possible the first volatile abundances to be obtained from the HIMU mantle end-member. We also report major and trace element abundances and Pb-isotopic ratios on the inclusions, which have HIMU isotopic fingerprints. We evaluate the samples for processes that could modify the volatile and trace element abundances postmantle melting, including diffusive Fe and H2O loss, degassing, and assimilation. H2O/Ce ratios vary from 119 to 245 in the most pristine Mangaia inclusions; excluding an inclusion that shows evidence for assimilation, the primary magmatic H2O/Ce ratios vary up to ∼200, and are consistent with significant dehydration of oceanic crust during subduction and long-term storage in the mantle. CO2 concentrations range up to 2346 ppm CO2 in the inclusions. Relatively high CO2 in the inclusions, combined with previous observations of carbonate blebs in other Mangaia melt inclusions, highlight the importance of CO2 for the generation of the HIMU mantle. F/Nd ratios in the inclusions (30 ± 9; 2σ standard deviation) are higher than the canonical ratio observed in oceanic lavas, and Cl/K ratios (0.079 ± 0.028) fall in the range of pristine mantle (0.02–0.08).

  • 230. Cahill, James A
    et al.
    Stirling, Ian
    Kistler, Logan
    Salamzade, Rauf
    Ersmark, Erik
    Swedish Museum of Natural History, Department of Bioinformatics and Genetics. Stockholms Universitet.
    Fulton, Tara L
    Stiller, Mathias
    Green, Richard E
    Shapiro, Beth
    Genomic evidence of geographically widespread effect of gene flow from polar bears into brown bears.2015In: Molecular Ecology, ISSN 0962-1083, E-ISSN 1365-294XArticle in journal (Refereed)
    Abstract [en]

    Polar bears are an arctic, marine adapted species that is closely related to brown bears. Genome analyses have shown that polar bears are distinct and genetically homogeneous in comparison to brown bears. However, these analyses have also revealed a remarkable episode of polar bear gene flow into the population of brown bears that colonized the Admiralty, Baranof, and Chichagof Islands (ABC Islands) of Alaska. Here, we present an analysis of data from a large panel of polar bear and brown bear genomes that includes brown bears from the ABC Islands, the Alaskan mainland and Europe. Our results provide clear evidence that gene flow between the two species had a geographically wide impact, with polar bear DNA found within the genomes of brown bears living both on the ABC Islands and in the Alaskan mainland. Intriguingly, while brown bear genomes contain up to 8.8% polar bear ancestry, polar bear genomes appear to be devoid of brown bear ancestry, suggesting the presence of a barrier to gene flow in that direction. This article is protected by copyright. All rights reserved.

  • 231. Callac, Nolwenn
    et al.
    Posth, Nicole
    Rattray, Jane
    Yamoah, Kweiku
    Wiech, Alan
    Ivarsson, Magnus
    Swedish Museum of Natural History, Department of Paleobiology.
    Hemmingsson, Christoffer
    Kilias, Stephanos
    Argyraki, Ariadne
    Broman, Curt
    Skogby, Henrik
    Smittenberg, Rienk
    Chi Fru, Ernest
    Modes of carbon fixation in an arsenic and CO2-rich shallow hydrothermal ecosystem2017In: Scientific ReportsArticle in journal (Refereed)
  • 232.
    Canfield, Donald E.
    et al.
    University of Southern Denmark.
    Ngombi Pemba, Lauriss
    Hammarlund, Emma
    Bengtson, Stefan
    Swedish Museum of Natural History, Department of Paleobiology.
    Chaussidon, Marc
    Gauthier Lafaye, François
    Meunier, Alain
    Riboulleau, Armelle
    Rollion Bard, Claire
    Rouxel, Olivier
    Asael, Dan
    Wickmann, Anne Catherine
    El Albani, Abderrazak
    Oxygen dynamics in the aftermath of the Great Oxidation of the Earth’s atmosphere.2013In: Proceedings of the National Academy of Sciences, ISSN 0027-8424, Vol. 110, no 42, p. 16736-16741Article in journal (Refereed)
    Abstract [en]

    The oxygen content of Earth’s atmosphere has varied greatly through time, progressing from exceptionally low levels before about 2.3 billion years ago, to much higher levels afterward. In the absence of better information, we usually view the progress in Earth’s oxygenation as a series of steps followed by periods of relative stasis. In contrast to this view, and as reported here, a dynamic evolution of Earth’s oxygenation is recorded in ancient sediments from the Republic of Gabon from between about 2,150 and 2,080 million years ago. The oldest sediments in this sequence were deposited in well-oxygenated deep waters whereas the youngest were deposited in euxinic waters, which were globally extensive. These fluctuations in oxygenation were likely driven by the comings and goings of the Lomagundi carbon isotope excursion, the longest–lived positive ?13C excursion in Earth history, generating a huge oxygen source to the atmosphere. As the Lomagundi event waned, the oxygen source became a net oxygen sink as Lomagundi organic matter became oxidized, driving oxygen to low levels; this state may have persisted for 200 million years.

  • 233.
    Cannon, Johanna
    et al.
    Swedish Museum of Natural History, Department of Zoology. Auburn University.
    Kocot, Kevin
    University of Alabama.
    Phylogenomic approaches using transcriptome data.2016In: Marine Genomics: Methods and Protocols / [ed] Sarah Bourlat, New York: Humana Press, 2016, p. 65-80Chapter in book (Other academic)
  • 234.
    Cannon, Johanna
    et al.
    Swedish Museum of Natural History, Department of Zoology. Auburn University.
    Kocot, Kevin
    University of Queensland.
    Waits, Damien
    Auburn University.
    Weese, David
    Georgia College and State University.
    Swalla, Billie
    University of Washington.
    Santos, Scott
    Auburn University.
    Halanych, Kenneth
    Auburn University.
    Phylogenomic Resolution of the Hemichordate and Echinoderm Clade2014In: Current Biology, ISSN 0960-9822, E-ISSN 1879-0445, Vol. 24, p. 2827-2832Article in journal (Refereed)
    Abstract [en]

    Ambulacraria, comprising Hemichordata and Echinodermata, is closely related to Chordata, making it integral to understanding chordate origins and polarizing chordate molecular and morphological characters. Unfortunately, relationships within Hemichordata and Echinoder- mata have remained unresolved, compromising our ability to extrapolate findings from the most closely related molecular and developmental models outside of Chordata (e.g., the acorn worms Saccoglossus kowalevskii and Ptychodera flava and the sea urchin Strongylocentrotus purpuratus). To resolve long-standing phylogenetic issues within Ambulacraria, we sequenced transcriptomes for 14 hemichordates as well as 8 echinoderms and complemented these with existing data for a total of 33 ambulacrarian operational taxonomic units (OTUs). Examination of leaf stability values revealed rhabdopleurid pterobranchs and the enteropneust Stereobalanus canadensis were unstable in placement; therefore, analyses were also run without these taxa. Analyses of 185 genes resulted in reciprocal monophyly of Enteropneusta and Pterobranchia, placed the deep-sea family Torquaratoridae within Ptychoderidae, and confirmed the position of ophiuroid brittle stars as sister to asteroid sea stars (the Asterozoa hypothesis). These results are consistent with earlier perspectives concerning plesiomorphies of Ambulacraria, including pharyngeal gill slits, a single axocoel, and paired hydrocoels and somatocoels. The resolved ambulacrarian phylogeny will help clarify the early evolution of chordate characteristics and has implications for our understanding of major fossil groups, including graptolites and somasteroideans. 

  • 235.
    Cannon, Johanna
    et al.
    Swedish Museum of Natural History, Department of Zoology. Auburn University.
    Vellutini, Bruno
    Sars International Centre for Marine Molecular Biology.
    Smith, Julian
    Winthrop University.
    Ronquist, Fredrik
    Swedish Museum of Natural History, Department of Bioinformatics and Genetics.
    Jondelius, Ulf
    Swedish Museum of Natural History, Department of Zoology.
    Hejnol, Andreas
    Sars International Centre for Marine Molecular Biology.
    Xenacoelomorpha is the sister group to Nephrozoa2016In: Nature, ISSN ISSN: 0028-0836, Vol. 530, p. 89-93Article in journal (Refereed)
    Abstract [en]

    The position of Xenacoelomorpha in the tree of life remains a major unresolved question in the study of deep animal relationships1. Xenacoelomorpha, comprising Acoela, Nemertodermatida, and Xenoturbella, are bilaterally symmetrical marine worms that lack several features common to most other bilaterians, for example an anus, nephridia, and a circulatory system. Two conflicting hypotheses are under debate: Xenacoelomorpha is the sister group to all remaining Bilateria (= Nephrozoa, namely protostomes and deuterostomes)2,3 or is a clade inside Deuterostomia4. Thus, determining the phylogenetic position of this clade is pivotal for understanding the early evolution of bilaterian features, or as a case of drastic secondary loss of complexity. Here we show robust phylogenomic support for Xenacoelomorpha as the sister taxon of Nephrozoa. Our phylogenetic analyses, based on 11 novel xenacoelomorph transcriptomes and using different models of evolution under maximum likelihood and Bayesian inference analyses, strongly corroborate this result. Rigorous testing of 25 experimental data sets designed to exclude data partitions and taxa potentially prone to reconstruction biases indicates that long- branch attraction, saturation, and missing data do not influence these results. The sister group relationship between Nephrozoa and Xenacoelomorpha supported by our phylogenomic analyses implies that the last common ancestor of bilaterians was probably a benthic, ciliated acoelomate worm with a single opening into an epithelial gut, and that excretory organs, coelomic cavities, and nerve cords evolved after xenacoelomorphs separated from the stem lineage of Nephrozoa. 

  • 236. Cappellini, Enrico
    et al.
    Gentry, Anthea
    Palkopoulou, Eleftheria
    Ishida, Yasuko
    Cram, David
    Roos, Anna-Marie
    Watson, Mick
    Johansson, Ulf S.
    Swedish Museum of Natural History, Department of Zoology.
    Fernholm, Bo
    Swedish Museum of Natural History, Department of Zoology.
    Agnelli, Paolo
    Barbagli, Fausto
    Littlewood, D. Tim. J.
    Kelstrup, Christian D.
    Olsen, Jesper V.
    Lister, Adrian M.
    Roca, Alfred L.
    Dalén, Love
    Swedish Museum of Natural History, Department of Bioinformatics and Genetics.
    Gilbert, M. Thomas P.
    Resolution of the type material of the Asian elephant, Elephas maximus Linnaeus, 1758 (Proboscidea, Elephantidae)2014In: Zoological Journal of the Linnean Society, ISSN 0024-4082, E-ISSN 1096-3642, Vol. 170, p. 222-232Article in journal (Refereed)
  • 237.
    Carlström, Julia
    Swedish Museum of Natural History, Department of Environmental research and monitoring.
    ASCOBANS Recovery Plan for Baltic Harbour Porpoises: Jastarnia Plan (2016 Revision)2016Report (Other academic)
    Abstract [en]

    This is the ASCOBANS species action plan for what is called Baltic harbour porpoise population primarily inhabiting the Baltic Proper. The population’s abundance has recently been estimated at only 497 individuals (95% CI 80 –1091) and it has a wide overall distribution range. During the winter season, it stretches from the Åland and Archipelago Seas in the north, to the Southern Baltic Proper in the southwest, and perhaps even further west thereof. In the summer season, however, when calving and mating take place, the majority of the population aggregates at and around the Hoburg’s and Northern and Southern Mid-sea banks in the Baltic Proper. Thus, this area should be considered essential and probably the main breeding area for the Baltic harbour porpoise population. The population’s current status calls for immediate conservation actions. Bycatch in gillnet fisheries has been recognized as the primary threat for the survival of the Baltic harbour porpoise population, although high contaminant levels are also of serious concern. Continuous and impulsive underwater noise and possibly also reduced prey quality are further contributing factors.

    The Jastarnia Plan serves as a framework for international collaboration towards achieving ASCOBANS’ interim goal of restoring the population to at least 80per cent of carrying capacity, and, ultimately, a favourable conservation status for Baltic harbour porpoises. The plan lists a number of actions, of which the following should be carried out as a matter of urgency:

    1.Involve stakeholders, use alternative fishing gear, apply available technology such as pingers, and reduce or eliminate fishing effort to reduce the number of bycaught harbour porpoises in the Baltic towards zero.

    2.Designate marine protected areas for harbour porpoises together with management plans and monitoring schemes for efficient contribution to the protection and monitoring of the population.

    3.Minimize the impact of anthropogenic underwater noise through the use of available mitigation measures and implementation of internationally harmonized national threshold limits and guidelines.

    The outline of the Plan is as follows:

    1.Introduction: An outline of the scope, context and policy setting of the Plan, including information on previous conservation management actions, as well as overall objectives.

    2.Legal frameworks: A list of relevant legal frameworks, including international conventions and agreements, European and national legislation and management arrangements.

    3.Governance: An outline of the management structure identifying the roles, responsibilities and interactions between the key stakeholders, as well as the timeline from the development stage through the implementation and review stages.

    4.Scientific background: Information on biology, status, environmental parameters, critical habitats, and attributes of the population to be monitored.

    5.Threats, mitigation measures and monitoring: A summary of the known or suspected threats together with a discussion of their evidence of impact, and the mitigation measures for the key threats and how they will be monitored.

    6.Actions: Descriptions of actions including information such as concise objective, rationale, activity or method, timeline, actors and priority.

  • 238. Carlén, Ida
    et al.
    Thomas, Len
    Carlström, Julia
    Swedish Museum of Natural History, Department of Environmental research and monitoring.
    Amundin, Mats
    Teilmann, Jonas
    Tregenza, Nick
    Tougaard, Jakob
    Koblitz, Jens C
    Sveegaard, Signe
    Wennerberg, Daniel
    Loisa, Olli
    Dähne, Michael
    Brundiers, Katharina
    Kosecka, Monika
    Kyhn, Line A
    Tiberi Ljungqvist, Cinthia
    Pawliczka, Iwona
    Koza, Radomil
    Arciszewski, Bartlomiej
    Galatius, Anders
    Jabbusch, Martin
    Laaksonlaita, Jussi
    Niemi, Jussi
    Lyytinen, Sami
    Gallus, Anja
    Benke, Harald
    Blankett, Penina
    Skóra, Krzysztof E
    Acevedo-Gutiérrez, Alejandro
    Basin-scale distribution of harbour porpoises in the Baltic Sea provides basisfor effective conservation actions2018In: Biological Conservation, ISSN 0006-3207, E-ISSN 1873-2917, Vol. 226, p. 42-53Article in journal (Refereed)
  • 239.
    CARPENTER, RAYMOND
    et al.
    University of Tasmania.
    McLoughlin, Stephen
    Swedish Museum of Natural History, Department of Paleobiology.
    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 AUSTRALIA2014In: American Journal of Botany, ISSN 0002-9122, E-ISSN 1537-2197, Vol. 101, no 9, p. 1486-1497Article in journal (Refereed)
    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.

  • 240. Chaline, J.
    et al.
    Werdelin, LarsSwedish Museum of Natural History, Department of Paleobiology.
    Modes and Tempos of Evolution of Quaternary Mammals1993Collection (editor) (Refereed)
  • 241. Chang, Dan
    et al.
    Knapp, Michael
    Enk, Jacob
    Lippold, Sebastian
    Kircher, Martin
    Lister, Adrian
    MacPhee, Ross D. E.
    Widga, Christopher
    Czechowski, Paul
    Sommer, Robert
    Hodges, Emily
    Stuempel, Nikolaus
    Barnes, Ian
    Dalen, Love
    Swedish Museum of Natural History, Department of Bioinformatics and Genetics.
    Derevianko, Anatoly
    Germonpre, Mietje
    Hillebrand-Voiculescu, Alexandra
    Constantin, Silviu
    Kuznetsova, Tatyana
    Mol, Dick
    Rathgeber, Thomas
    Rosendahl, Wilfried
    Tikhonov, Alexey N.
    Willerslev, Eske
    Hannon, Greg
    Lalueza-Fox, Carles
    Joger, Ulrich
    Poinar, Hendrik
    Hofreiter, Michael
    Shapiro, Beth
    The evolutionary and phylogeographic history of woolly mammoths: a comprehensive mitogenomic analysis2017In: Scientific Reports, ISSN 2045-2322, E-ISSN 2045-2322, Vol. 7, article id 44585Article in journal (Refereed)
  • 242.
    Charette, M
    et al.
    Woods Hole Oceanographic Institution, USA.
    Lam, P.J.
    University of California Santa Cruz, USA.
    Lohan, M.C.
    University of Southhampton, UK.
    Kwon, E.Y.
    Seoul National University,Korea.
    Hatje, V
    Universidade Federal da Bahia, Brazil.
    Jeandel, C
    University of Toulouse, France.
    Shiller, A.M.
    University of Southern Mississippi, USA.
    Cutter, G.A.
    Old Dominion University, USA.
    Thomas, A
    University of Edinburgh, UK.
    Boyd, P.W.
    University of Tasmania, Australia.
    Homoky, W.B.
    University of Oxford, UK.
    Milne, A.
    Plymoth University, UK.
    Thomas, H.
    Dalhousie University, Canada.
    Andersson, P.S.
    Swedish Museum of Natural History, Department of Geology.
    Porcelli, D.
    University of Oxford,Uk.
    Tanaka, T
    University of Tokyo, Japan.
    Geibert, W
    Alfred Wegener Institute, Germany.
    Dehairs, F.
    Vrije Universiteit, Belgium.
    Garcia-Orellana, J.
    Universitat Autonoma de Barcelona, Spain.
    Coastal ocean and shelf-sea biogeochemical cycling of trace elements and isotopes: lessons learned from GEOTRACES2016In: Philosopical Transactions of the Royal Society A, ISSN 1364–503X, Vol. 374, no 2081Article, review/survey (Refereed)
    Abstract [en]

    Continental shelves and shelf seas play a central role in the global carbon cycle. However,

    their importance with respect to trace element and isotope (TEI) inputs to ocean basins

    is less well understood. Here, we present major findings on shelf TEI biogeochemistry

    from the GEOTRACES programme as well as a proof of concept for a new method to

    estimate shelf TEI fluxes. The case studies focus on advances in our understanding of TEI

    cycling in the Arctic, transformations within a major river estuary (Amazon), shelf sediment

    micronutrient fluxes and basin-scale estimates of submarine groundwater discharge. The

    proposed shelf flux tracer is 228-radium (T1/2 =5.75 yr), which is continuously supplied to

    the shelf from coastal aquifers, sediment porewater exchange and rivers. Model-derived shelf

    228Ra fluxes are combined with TEI/ 228Ra ratios to quantify ocean TEI fluxes from the

    western North Atlantic margin. The results from this new approach agree well with previous

    estimates for shelf Co, Fe, Mn and Zn inputs and exceed published estimates of atmospheric

    deposition by factors of approximately 3–23. Lastly, recommendations are made for additional

    GEOTRACES process studies and coastal margin-focused section cruises that will help refine

    the model and provide better insight on the mechanisms driving shelf-derived TEI fluxes

    to the ocean.

    This article is part of the themed issue ‘Biological and climatic impacts of ocean trace element

    chemistry’.

  • 243. Chenery, S.
    et al.
    Williams, C. T.
    Elliott, T. A.
    Forey, P. L.
    Werdelin, Lars
    Swedish Museum of Natural History, Department of Paleobiology.
    Determination of rare earth elements in biological and mineral apatite by EPMA and LAMP-ICP-MS1996In: Mikrochimica Acta, ISSN 0026-3672, E-ISSN 1436-5073, Vol. 13, no suppl., p. 259-269Article in journal (Refereed)
  • 244. Chenhall, R
    et al.
    Martinelli, L
    McLaughlin, J
    Paulsen, B S
    Senior, K
    Svalastog, A L
    Tunon, H
    Werdelin, Lars
    Swedish Museum of Natural History, Department of Paleobiology.
    Culture, science and bioethics - Interdisciplinary understandings of and practices in science, culture and ethics2014In: New Zealand Online Journal of Interdisciplinary Studies, Vol. 1, no 2Article in journal (Refereed)
  • 245. Chi Fru, E.
    et al.
    Ivarsson, M.
    Swedish Museum of Natural History, Department of Geology.
    Kilias, S. P.
    Frings, Patrick J
    Swedish Museum of Natural History, Department of Geology.
    Hemmingsson, C.
    Broman, C.
    Bengtson, S.
    Swedish Museum of Natural History, Department of Paleobiology.
    Chatzitheodoridis, E.
    Biogenicity of an Early Quaternary iron formation, Milos Island, Greece2015In: Geobiology, ISSN 1472-4677, E-ISSN 1472-4669, Vol. 13, no 3, p. 225-244Article in journal (Refereed)
    Abstract [en]

    A ~2.0-million-year-old shallow-submarine sedimentary deposit on Milos Island, Greece, harbours an unmetamorphosed fossiliferous iron formation (IF) comparable to Precambrian banded iron formations (BIFs). This Milos IF holds the potential to provide clues to the origin of Precambrian BIFs, relative to biotic and abiotic processes. Here, we combine field stratigraphic observations, stable isotopes of C, S and Si, rock petrography and microfossil evidence from a ~5-m-thick outcrop to track potential biogeochemical processes that may have contributed to the formation of the BIF-type rocks and the abrupt transition to an overlying conglomerate-hosted IF (CIF). Bulk δ13C isotopic compositions lower than -25‰ provide evidence for biological contribution by the Calvin and reductive acetyl–CoA carbon fixation cycles to the origin of both the BIF-type and CIF strata. Low S levels of ~0.04 wt.% combined with δ34S estimates of up to ~18‰ point to a non-sulphidic depository. Positive δ30Si records of up to +0.53‰ in the finely laminated BIF-type rocks indicate chemical deposition on the seafloor during weak periods of arc magmatism. Negative δ30Si data are consistent with geological observations suggesting a sudden change to intense arc volcanism potentially terminated the deposition of the BIF-type layer. The typical Precambrian rhythmic rocks of alternating Fe- and Si-rich bands are associated with abundant and spatially distinct microbial fossil assemblages. Together with previously proposed anoxygenic photoferrotrophic iron cycling and low sedimentary N and C potentially connected to diagenetic denitrification, the Milos IF is a biogenic submarine volcano-sedimentary IF showing depositional conditions analogous to Archaean Algoma-type BIFs.

  • 246. Chi Fru, Ernest
    et al.
    Callac, Nolwenn
    Posth, Nicole
    Argyaki, Ariadne
    Ling, Y.-C.
    Ivarsson, Magnus
    Swedish Museum of Natural History, Department of Paleobiology.
    Broman, Curt
    Kilias, Stephanos
    Arsenic and high affinity phosphate uptake gene distribution in shallow submarine hydrothermal sediments2018In: Biogeosciences, ISSN 1726-4170, E-ISSN 1726-4189Article in journal (Refereed)
  • 247. Chi Fru, Ernest
    et al.
    Ivarsson, Magnus
    Swedish Museum of Natural History, Department of Paleobiology.
    Kilias, Stephanos
    Christoffer, Hemmingson
    Broman, Curt
    Bengtson, Stefan
    C, Chatzitheodoridis
    Biogenicity of an early Quaternary iron formation, Milos Island, Greece2015In: Geobiology, ISSN 1472-4677, E-ISSN 1472-4669, Vol. 13, p. 225-244Article in journal (Refereed)
  • 248. Chi Fru, Ernest
    et al.
    Ivarsson, Magnus
    Swedish Museum of Natural History, Department of Paleobiology.
    Kilias, Stephanos P
    Bengtson, Stefan
    Swedish Museum of Natural History, Department of Paleobiology.
    Belivanova, Veneta
    Swedish Museum of Natural History, Department of Paleobiology.
    Marone, Federica
    Paul Scherrer Institute.
    Fortin, Danielle
    Broman, Curt
    Stampanoni, Marco
    ETH Zürich.
    Fossilized iron bacteria reveal pathway to biological origin of banded iron formation.2013In: Nature Communications, ISSN 2041-1723, Vol. 4, no 2050, p. 1-7Article in journal (Refereed)
    Abstract [en]

    Debates on the formation of banded iron formations in ancient ferruginous oceans are dominated by a dichotomy between abiotic and biotic iron cycling. This is fuelled by difficulties in unravelling the exact processes involved in their formation. Here we provide fossil environmental evidence for anoxygenic photoferrotrophic deposition of analogue banded iron rocks in shallow marine waters associated with an Early Quaternary hydrothermal vent field on Milos Island, Greece. Trace metal, major and rare earth elemental compositions suggest that the deposited rocks closely resemble banded iron formations of Precambrian origin. Well-preserved microbial fossils in combination with chemical data imply that band formation was linked to periodic massive encrustation of anoxygenic phototrophic biofilms by iron oxyhydroxide alternating with abiotic silica precipitation. The data implicate cyclic anoxygenic photoferrotrophy and their fossilization mechanisms in the construction of microskeletal fabrics that result in the formation of characteristic banded iron formation bands of varying silica and iron oxide ratios.

  • 249. Chi Fru, Ernest
    et al.
    Kilias, Stephanos
    Ivarsson, Magnus
    Swedish Museum of Natural History, Department of Paleobiology.
    Rattray, Jane
    Gkika, Katerina
    McDonald, Iain
    He, Qian
    Broman, Curt
    Sedimentary mechanisms of a modern banded ironformation on Milos Island, GreeceIn: Solid earthArticle in journal (Refereed)
  • 250.
    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
    Swedish Museum of Natural History, Department of Paleobiology.
    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, Greece2018In: Solid Earth, ISSN 1869-9510, E-ISSN 1869-9529, Vol. 9, p. 573-598Article in journal (Refereed)
    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.

2345678 201 - 250 of 2054
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