Change search
Refine search result
123 1 - 50 of 128
CiteExportLink to result list
Permanent link
Cite
Citation style
  • apa
  • ieee
  • modern-language-association-8th-edition
  • vancouver
  • Other style
More styles
Language
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Other locale
More languages
Output format
  • html
  • text
  • asciidoc
  • rtf
Rows per page
  • 5
  • 10
  • 20
  • 50
  • 100
  • 250
Sort
  • Standard (Relevance)
  • Author A-Ö
  • Author Ö-A
  • Title A-Ö
  • Title Ö-A
  • Publication type A-Ö
  • Publication type Ö-A
  • Issued (Oldest first)
  • Issued (Newest first)
  • Created (Oldest first)
  • Created (Newest first)
  • Last updated (Oldest first)
  • Last updated (Newest first)
  • Disputation date (earliest first)
  • Disputation date (latest first)
  • Standard (Relevance)
  • Author A-Ö
  • Author Ö-A
  • Title A-Ö
  • Title Ö-A
  • Publication type A-Ö
  • Publication type Ö-A
  • Issued (Oldest first)
  • Issued (Newest first)
  • Created (Oldest first)
  • Created (Newest first)
  • Last updated (Oldest first)
  • Last updated (Newest first)
  • Disputation date (earliest first)
  • Disputation date (latest first)
Select
The maximal number of hits you can export is 250. When you want to export more records please use the Create feeds function.
  • 1. Adrian, Brent
    et al.
    Werdelin, Lars
    Swedish Museum of Natural History, Department of Paleobiology.
    Grossman, Aryeh
    New Miocene Carnivora (Mammalia) from Moruorot and Kalodirr, Kenya2018In: Palaeontologia Electronica, ISSN 1935-3952, E-ISSN 1094-8074, Vol. 21Article in journal (Refereed)
    Abstract [en]

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

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

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

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

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

    known diversity of African Early Miocene carnivorans and highlight regional differences

    in Africa.

  • 2.
    Anderson, Heidi
    et al.
    Dorrigo, NSW, Australia.
    David J. Batten, David
    Manchester University.
    Cantrill, David
    National Herbarium of Victoria, Royal Botanic Gardens Melbourne.
    Cleal, Christopher
    Museum of Wales.
    Susanne Feist-Burkhardt, Susanne
    SFB Geological Consulting & Services, Odenwaldstrasse 18, D-64372 Ober-Ramstadt, Germany.
    Fensome, Robert
    Natural Resources Canada.
    Head, Martin
    Brock University, Canada.
    Herendeen, Patrick
    Chicago Botanuic Garden.
    Jaramillo, Carlos
    Smithsonian Institution.
    Kvaček, Jiří
    Czech National Museum, Prague.
    McLoughlin, Stephen
    Swedish Museum of Natural History, Department of Paleobiology.
    Skog, Judith
    George Mason University.
    Takahashi, Masamichi
    Niigata University.
    Wicander, Reed
    Department of Earth and Atmospheric Sciences, Central Michigan University .
    (087–090) Proposal to treat the use of a hyphen in the name of a fossil-genus as an orthographical error2015In: Taxon, ISSN 0040-0262, E-ISSN 1996-8175Article in journal (Refereed)
    Abstract [en]

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

  • 3.
    Bercovici, Antoine
    et al.
    Department of Geology, Lund University, Sölvegatan 12, SE-223 62 Lund, Sweden.
    Cui, Ying
    Department of Geosciences, 512 Deike Building, The Pennsylvania State University, University Park, PA 16802, USA.
    Forel, Marie-Béatrice
    State Key Laboratory of Biogeology and Environmental Geology of Ministry of Education, China University of Geosciences, Wuhan 430074, People’s Republic of China.
    Vajda, Vivi
    Swedish Museum of Natural History, Department of Paleobiology. Department of Geology, Lund University, Sweden.
    Terrestrial paleoenvironment characterization across the Permian–Triassic boundary in South China2015In: Journal of Asian Earth Sciences, ISSN 1367-9120, Vol. 98, p. 225-246Article in journal (Refereed)
    Abstract [en]

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

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

  • 4.
    Bergström, Jan
    et al.
    Swedish Museum of Natural History, Department of Paleobiology.
    Hou, Xian-Guang
    Yunnan University, Kunming.
    Hålenius, Ulf
    Swedish Museum of Natural History, Department of Geology.
    Gut contents and feeding in the Cambrian arthropod Naraoia2007In: GFF, ISSN 1103-5897, E-ISSN 2000-0863, Vol. 129, p. 71-76Article in journal (Refereed)
  • 5. Bibi, Faysal
    et al.
    Pante, Michael
    Souron, Antoine
    Stewart, Kathlyn
    Varela, Sara
    Werdelin, Lars
    Swedish Museum of Natural History, Department of Paleobiology.
    Boisserie, Jean-Renaud
    Fortelius, Mikael
    Hlusko, Leslea
    Njau, Jackson
    de la Torre, Ignacio
    Paleoecology of the Serengeti during the Oldowan-Acheulean transition at Olduvai Gorge, Tanzania: The mammal and fish evidence2017In: Journal of Human Evolution, ISSN 0047-2484, E-ISSN 1095-8606Article in journal (Refereed)
    Abstract [en]

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

  • 6.
    Bomfleur, Benjamin
    et al.
    Swedish Museum of Natural History, Department of Paleobiology.
    Decombeix, Anne-Laure
    Schwendemann, Andrew
    Escapa, Ignacio
    Taylor, Edith
    Taylor, Thomas
    McLoughlin, Stephen
    Swedish Museum of Natural History, Department of Paleobiology.
    Habit and Ecology of the Petriellales, an Unusual Group of Seed Plants from the Triassic of Gondwana2014In: International journal of plant sciences, ISSN 1058-5893, E-ISSN 1537-5315, Vol. 175, no 9, p. 1062-1075Article in journal (Refereed)
    Abstract [en]

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

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

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

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

  • 7.
    Bomfleur, Benjamin
    et al.
    Swedish Museum of Natural History, Department of Paleobiology.
    Grimm, Guido
    Swedish Museum of Natural History, Department of Paleobiology.
    McLoughlin, Stephen
    Swedish Museum of Natural History, Department of Paleobiology.
    Osmunda pulchella sp. nov. from the Jurassic of Sweden--reconciling molecular and fossil evidence in the phylogeny of modern royal ferns (Osmundaceae)2015In: BMC Evolutionary Biology, ISSN 1471-2148, E-ISSN 1471-2148, Vol. 15, no 126, p. 1-25Article in journal (Refereed)
    Abstract [en]

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

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

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

  • 8.
    Bomfleur, Benjamin
    et al.
    Swedish Museum of Natural History, Department of Paleobiology. Westfälische Wilhelms-Universität Münster.
    Grimm, Guido
    Department fu¨r Pala¨ontologie, Universita¨t Wien, Wien, Austria.
    McLoughlin, Stephen
    Swedish Museum of Natural History, Department of Paleobiology.
    The fossil Osmundales (Royal Ferns)—a phylogenetic network analysis, revised taxonomy, and evolutionary classification of anatomically preserved trunks and rhizomes2017In: PeerJ, ISSN 2167-8359, E-ISSN 2167-8359, Vol. 5, article id e3433Article in journal (Refereed)
    Abstract [en]

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

  • 9.
    Bomfleur, Benjamin
    et al.
    Swedish Museum of Natural History, Department of Paleobiology.
    Klymiuk, Ashley
    Taylor, Edith
    Taylor, Thomas
    Gulbranson, Erik
    Isbell, John
    Diverse bryophyte mesofossils from the Triassic of Antarctica2014In: Lethaia: an international journal of palaeontology and stratigraphy, ISSN 0024-1164, E-ISSN 1502-3931, Vol. 47, no 1, p. 120-132Article in journal (Refereed)
    Abstract [en]

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

  • 10.
    Bomfleur, Benjamin
    et al.
    Swedish Museum of Natural History, Department of Paleobiology.
    Schöner, Robert
    John, Nadine
    Schneider, Jörg
    Elsner, Martin
    Viereck-Goette, Lothar
    Kerp, Hans
    New Palaeozoic deposits of the Victoria Group in the Eisenhower Range, northern Victoria Land, Antarctica2014In: Antarctic Science, ISSN 0954-1020, E-ISSN 1365-2079, Vol. 26, no 3, p. 277-278Article in journal (Refereed)
  • 11.
    Bomfleur, Benjamin
    et al.
    Swedish Museum of Natural History, Department of Paleobiology.
    Schöner, Robert
    Schneider, Jörg
    Viereck, Lothar
    Kerp, Hans
    McKellar, John
    From the Transantarctic Basin to the Ferrar Large Igneous Province: New palynostratigraphic age constraints for Triassic-Jurassic sedimentation and magmatism in East Antarctica2014In: Review of Palaeobotany and Palynology, ISSN 0034-6667, E-ISSN 1879-0615, Vol. 207, p. 18-37Article in journal (Refereed)
    Abstract [en]

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

  • 12.
    Bosi, Ferdinando
    University of Rome "La Sapienza".
    Balik-Zunic, Tonci
    Natural History Museum of Denmark.
    Thermal stability of extended clusters in dravite: a combined EMP, SREF and FTIR study.2016In: Physics and chemistry of minerals, ISSN 0342-1791, E-ISSN 1432-2021, Vol. 43, p. 395-407Article in journal (Refereed)
  • 13. 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.

  • 14.
    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.

  • 15. Chiappe, Luis M
    et al.
    Lamb, James P
    Ericson, Per G P
    Swedish Museum of Natural History, Research Division.
    New enantiornithine bird from the marine Upper Cretaceous of Alabama2002In: Journal of Vertebrate Paleontology, ISSN 0272-4634, E-ISSN 1937-2809, Vol. 22, no 1, p. 170-174Article in journal (Refereed)
  • 16.
    Choo, Thereis
    et al.
    School of Integrative Plant Science, Cornell University, Ithaca,.
    Escapa, Ignacio
    CONICET, Museo Paleontológico Egidio Feruglio, Trelew U9100GYO, Chubut, Argentina.
    Benjamin, Bomfleur
    Swedish Museum of Natural History, Department of Paleobiology.
    Monotypic colonies of Clathropteris meniscioides (Dipteridaceae) from the Early Jurassic of central Patagonia, Argentina: implications for taxonomy and palaeoecology2016In: Palaeontographica. Abteilung B, Palaophytologie, ISSN 0375-0299, Vol. 294, p. 85-109Article in journal (Refereed)
    Abstract [en]

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

  • 17.
    Chris, Mays
    et al.
    Swedish Museum of Natural History, Department of Paleobiology. Monash University.
    Bevitt, Joseph
    Australian Nuclear Science and Technology Organisation, Research Office, Lucas Heights, Australia.
    Stilwell, Jeffrey
    School of Earth, Atmosphere and Environment, Monash University, Clayton, Victoria, Australia.
    Pushing the limits of neutron tomography in palaeontology: Three-dimensional modelling of in situ resin within fossil plants2017In: Palaeontologia Electronica, ISSN 1935-3952, E-ISSN 1094-8074, Vol. 20, no 3, p. 1-12, article id 20.3.57AArticle in journal (Refereed)
    Abstract [en]

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

  • 18.
    Cui, Ying
    et al.
    Department of Geosciences, The Pennsylvania State University, University Park, PA, United States.
    Bercovici, Antoine
    Department of Geology, Lund University, Lund, Sweden.
    Yu, Jianxin
    State Key Laboratory of Biogeology and Environmental Geology of Ministry of Education, China University of Geosciences (Wuhan), People's Republic of China.
    Kump, Lee R.
    Department of Geosciences, The Pennsylvania State University, University Park, PA, United States.
    Freeman, Katherine
    Department of Geosciences, The Pennsylvania State University, University Park, PA, United States.
    Su, Shangguo
    School of Earth Sciences and Resources, China University of Geosciences (Beijing), People's Republic of China.
    Vajda, Vivi
    Swedish Museum of Natural History, Department of Paleobiology. Department of Geology, Lund University, Sweden.
    Carbon cycle perturbation expressed in terrestrial Permian–Triassic boundary sections in South China2017In: Global and Planetary Change, ISSN 0921-8181, E-ISSN 1872-6364, Vol. 148, p. 272-285Article in journal (Refereed)
    Abstract [en]

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

  • 19.
    Cunningham, John A.
    et al.
    Swedish Museum of Natural History, Department of Paleobiology. University of Bristol.
    Vargas, Kelly
    School of Earth Sciences, University of Bristol, Bristol.
    Yin, Zongjun
    State Key Laboratory of Palaeobiology and Stratigraphy, Nanjing Institute of Geology and Palaeontology, Chinese Academy of Sciences, Nanjing.
    Bengtson, Stefan
    Swedish Museum of Natural History, Department of Paleobiology.
    Donoghue, Philip C.J.
    University of Bristol.
    The Weng’an Biota (Doushantuo Formation): an Ediacaran window on soft bodied and multicellular microorganisms.2017In: journal of the geological society, ISSN 2041-479X, Vol. 174, no 5, p. 793-802Article in journal (Refereed)
    Abstract [en]

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

  • 20. Dalsätt, J
    et al.
    Zhou, Z
    Zhang, F
    Ericson, Per G P
    Swedish Museum of Natural History, Research Division.
    Food remains in Confuciusornis sanctus suggest a fish diet.2006In: Die Naturwissenschaften, ISSN 0028-1042, E-ISSN 1432-1904, Vol. 93, no 9, p. 444-6Article in journal (Refereed)
    Abstract [en]

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

  • 21.
    Dalsätt, Johan
    et al.
    Swedish Museum of Natural History, Department of Zoology.
    Mörs, Thomas
    Swedish Museum of Natural History, Department of Paleobiology.
    Ericson, Per G P
    Swedish Museum of Natural History, Research Division.
    Fossil birds from the Miocene and Pliocene of Hambach (NW Germany)2006In: Palaeontographica. Abteilung A, Palaozoologie, Stratigraphie, ISSN 0375-0442, Vol. 277, no 1-6, p. 113-+Article in journal (Refereed)
  • 22.
    Daume, Stefan
    Swedish Museum of Natural History, Department of Bioinformatics and Genetics. University of Göttingen; Stockholm Resilience Centre.
    Mining Twitter to monitor Invasive Alien Species – An analytical framework and sample information topologies2016In: Ecological Informatics, ISSN 1574-9541, E-ISSN 1878-0512, Vol. 31, p. 70-82Article in journal (Refereed)
    Abstract [en]

    Social online media increasingly emerge as important informal information sources that can contribute to the detection of trends and early warnings in critical fields such as public health monitoring or emergency management. In the face of global environmental challenges the utilization of this information in ecological monitoring contexts has been called for, but examples remain sparse. This can be attributed to the significant technical challenges in processing this data and concerns about the quality, reliability and applicability of information mined from social media to the ecological domain. Here the strength and weaknesses of social media mining for ecological monitoring are assessed using the micro-blogging service Twitter and invasive alien species (IAS) monitoring as an example. The assessment is based on a manual analysis of 2842 Tweets sampled from Twitter data with potential direct or descriptive references to IAS impacting forest ecosystems, which was collected over a period of nearly three years. The results are presented as information topologies for Twitter messages of observational and non-observational character for three IAS with distinctive characteristics (Oak Processionary Moth, Emerald Ash Borer, Eastern Grey Squirrel). The results show that the social media channel Twitter is a rich source of primary and secondary observational biodiversity information. It also provides useful insights in the topical landscape of public communications on IAS as well as the public perception of IAS and IAS management. The analysis suggests broad application opportunities in IAS monitoring and management, and points at applications for related environmental questions. The results highlight that social media mining for ecological monitoring needs to be approached with the same best practices as ecological monitoring in general, requiring a good understanding of the monitored subjects and specific monitoring questions. The challenges in utilizing this information for operational systems are of technical rather than conceptual nature and include extending the degree of automation, especially with regard to image recognition and the automatic provisioning of location information.

  • 23.
    Daume, Stefan
    et al.
    Swedish Museum of Natural History, Department of Bioinformatics and Genetics. University Göttingen, Germany.
    Albert, Matthias
    Northwest German Forest Research Institute.
    Gadow, von, Klaus
    University Göttingen, Germany.
    Assessing citizen science opportunities in forest monitoring using probabilistic topic modelling2014In: Forest Ecosystems, ISSN 2197-5620, Vol. 1, no 11, p. 1-12Article in journal (Refereed)
    Abstract [en]

    Background

    With mounting global environmental, social and economic pressures the resilience and stability of forests and thus the provisioning of vital ecosystem services is increasingly threatened. Intensified monitoring can help to detect ecological threats and changes earlier, but monitoring resources are limited. Participatory forest monitoring with the help of “citizen scientists” can provide additional resources for forest monitoring and at the same time help to communicate with stakeholders and the general public. Examples for citizen science projects in the forestry domain can be found but a solid, applicable larger framework to utilise public participation in the area of forest monitoring seems to be lacking. We propose that a better understanding of shared and related topics in citizen science and forest monitoring might be a first step towards such a framework.

    Methods

    We conduct a systematic meta-analysis of 1015 publication abstracts addressing “forest monitoring” and “citizen science” in order to explore the combined topical landscape of these subjects. We employ ‘topic modelling’, an unsupervised probabilistic machine learning method, to identify latent shared topics in the analysed publications.

    Results

    We find that large shared topics exist, but that these are primarily topics that would be expected in scientific publications in general. Common domain-specific topics are under-represented and indicate a topical separation of the two document sets on “forest monitoring” and “citizen science” and thus the represented domains. While topic modelling as a method proves to be a scalable and useful analytical tool, we propose that our approach could deliver even more useful data if a larger document set and full-text publications would be available for analysis.

    Conclusions

    We propose that these results, together with the observation of non-shared but related topics, point at under-utilised opportunities for public participation in forest monitoring. Citizen science could be applied as a versatile tool in forest ecosystems monitoring, complementing traditional forest monitoring programmes, assisting early threat recognition and helping to connect forest management with the general public. We conclude that our presented approach should be pursued further as it may aid the understanding and setup of citizen science efforts in the forest monitoring domain.

  • 24.
    Daume, Stefan
    et al.
    Swedish Museum of Natural History, Department of Bioinformatics and Genetics. University of Göttingen; Stockholm Resilience Centre.
    Galaz, Victor
    Stockholm Resilience Centre, Stockholm University.
    “Anyone Know What Species This Is?” – Twitter Conversations as Embryonic Citizen Science Communities2016In: PLoS ONE, ISSN 1932-6203, E-ISSN 1932-6203, Vol. 11, no 3Article in journal (Refereed)
    Abstract [en]

    Social media like blogs, micro-blogs or social networks are increasingly being investigated and employed to detect and predict trends for not only social and physical phenomena, but also to capture environmental information. Here we argue that opportunistic biodiversity observations published through Twitter represent one promising and until now unexplored example of such data mining. As we elaborate, it can contribute to real-time information to traditional ecological monitoring programmes including those sourced via citizen science activities. Using Twitter data collected for a generic assessment of social media data in ecological monitoring we investigated a sample of what we denote biodiversity observations with species determination requests (N = 191). These entail images posted as messages on the micro-blog service Twitter. As we show, these frequently trigger conversations leading to taxonomic determinations of those observations. All analysed Tweets were posted with species determination requests, which generated replies for 64% of Tweets, 86% of those contained at least one suggested determination, of which 76% were assessed as correct. All posted observations included or linked to images with the overall image quality categorised as satisfactory or better for 81% of the sample and leading to taxonomic determinations at the species level in 71% of provided determinations. We claim that the original message authors and conversation participants can be viewed as implicit or embryonic citizen science communities which have to offer valuable contributions both as an opportunistic data source in ecological monitoring as well as potential active contributors to citizen science programmes.

  • 25. Decombeix, Anne-Laure
    et al.
    Bomfleur, Benjamin
    Swedish Museum of Natural History, Department of Paleobiology.
    Taylor, Edith
    Taylor, Thomas
    New data on the anatomy and systematic affinities of corystosperm wood from the Triassic of Antarctica2014In: Review of Palaeobotany and Palynology, ISSN 0034-6667, E-ISSN 1879-0615, Vol. 203, no 1, p. 22-34Article in journal (Refereed)
    Abstract [en]

    Anatomically preserved trunks and young stems of corystosperm seed ferns are described from the Triassic of Fremouw Peak, Beardmore Glacier area, Antarctica. Based on characters of the primary and secondary vascular system, these new specimens are assigned to Kykloxylon, a genus that was established based on young stems with attached Dicroidium leaf bases. The largest specimens illustrate how some secondary growth characters, such as unequal cambial activity, appeared during later development, which enables a better comparison of Kykloxylon with trunks assigned to other corystosperm genera. Jeffersonioxylon from the Gordon Valley, Antarctica, and Cuneumxylon from South America show strong similarities with the newly described larger Kykloxylon trunks from Fremouw Peak, and might be considered congeneric. Our results provide further support for the presence of two anatomically and morphologically distinct kinds of Dicroidium-bearing trees in the Triassic vegetation of Gondwana, one with a palm-like habit and Rhexoxylon stems and the other with a more Ginkgo-like habit and Kykloxylon/Cuneumxylon-type stems

  • 26.
    Denk, Thomas
    et al.
    Swedish Museum of Natural History, Department of Paleobiology.
    Güner, Tuncay H.
    , Istanbul University, Istanbul, Turkey.
    Kvaček, Zlatko
    Charles University, Prague, Czech Republic.
    Bouchal, Johannes M.
    Swedish Museum of Natural History, Department of Paleobiology. johannes.bouchal@nrm.se.
    The early Miocene flora of Güvem (Central Anatolia, Turkey): a window into early Neogene vegetation and environments in the Eastern Mediterranean2017In: Acta Palaeobotanica, ISSN 0001-6594, E-ISSN 1427-6402, Vol. 57, no 2, p. 237-338Article in journal (Refereed)
    Abstract [en]

    The early Burdigalian (MN3) plant assemblage of the Güvem area (northwestern Central Anatolia) is preserved in lacustrine sediments of the Dereköy pyroclastics. Its age is well constrained by radiometric dates of basaltic rocks bracketing the pyroclastics, making the Güvem flora one of the extremely few precisely dated early Miocene floras in the Mediterranean region. The rich assemblage of impression fossils comprises ferns and fern allies (2 species), gymnosperms (12 spp.) and angiosperms (129 spp.). Ilex miodipyrena sp. nov. is described as a new fossil-species. The most diverse families in the assemblage are the Fagaceae with 12 taxa and the Fabaceae with 12 leaf morphotypes and one fruit taxon. Aquatic plants are represented by seven taxa, riparian (including palms) and swamp forest elements by >35 taxa, and lianas by three taxa (Smilax spp., Chaneya). The relatively large number of aquatic and riparian/swamp elements is congruent with the rich fish, amphibian and reptile record of the Güvem area. Another characteristic feature of the plant assemblage is the presence of various lobed leaves which show similarities with modern species of different families (e.g. Alangium, various Malvales). Trees and shrubs growing on well-drained soils and forming closed-canopy and open-canopy forests are the most diversified group (>70 taxa). In terms of number of specimens in the collection and based on field observations, by far the most abundant leaf fossils belong to evergreen oaks of Quercus drymeja and Q. mediterranea and to various types of foliage that cannot be assigned to a particular extant or extinct genus of Fagaceae. These sclerophyllous trees must have covered vast areas surrounding the wetlands that developed during the early Miocene in the Güvem Basin. Based on a recent reassessment of the ecology and taxonomic affinity of these trees, they are considered to reflect humid temperate climatic conditions but with a brief drier season during the winter months. These forests are more similar to the laurel forests of the southeastern United States and those stretching in a narrow belt south of the Himalayas to eastern central China. The large number of Fabaceae may indicate the presence of warm subtropical environments but this is difficult to assess, as they are known for having wide ecological ranges today and in the past. All in all, a larger part of the plant taxa point to forested vegetation. This is in agreement with previous palynological studies which detected only small amounts of herbaceous and grass pollen. Open patches of vegetation may have been restricted to river banks and to rocky areas in a volcanic landscape. The biogeographic patterns detected for the early Miocene of the Güvem assemblage are manifold; most taxa are widespread Northern Hemispheric elements. A substantial part of the species migrated from Asia into Europe during the (late) Paleogene and reached Anatolia during the early Miocene (Fagus, Paliurus, Chaneya, Ailanthus, Quercus kubinyii, Davallia haidingeri, Acer angustilobum, A. palaeosaccharinum). Fewer taxa may have been in Anatolia before they migrated to Europe (e.g. Nerium, Smilax miohavanensis, Quercus sosnowskyi). Finally, very few taxa are Anatolian endemics (e.g. Ilex miodipyrena).

  • 27. DiMaggio, Erin N.
    et al.
    Campisano, Christopher J.
    Rowan, John
    Dupont-Nivet, Guillaume
    Deino, Alan L.
    Bibi, Faysal
    Lewis, Margaret
    Souron, Antoine
    Werdelin, Lars
    Swedish Museum of Natural History, Department of Paleobiology.
    Reed, Kaye E.
    Arrowsmith, J. Ramon
    Late Pliocene Fossiliferous Sedimentary Record and the Environmental Context of early Homo from Afar, Ethiopia2015In: Science, Vol. 347, p. 1355-1359Article in journal (Refereed)
  • 28.
    Einarsson, Elisabeth
    Department of Geology, Lund University.
    Vajda, Vivi
    Swedish Museum of Natural History, Department of Paleobiology. Department of Geology, Lund University, Sweden.
    First evidence of the Cretaceous decapod crustacean Protocallianassa from Sweden2016In: Geological Society, London, Special Publications, ISSN ISSN 0305-8719, Vol. 434, p. 241-250Article in journal (Refereed)
    Abstract [en]

    An assemblage of the burrowing ghost shrimp, Protocallianassa faujasi, is described, providing the first evidence of this decapod species from Sweden. The fossils occur in successions of the informal earliest late Campanian Belemnellocamax balsvikensis Zone at Åsen and the latest early Campanian B. mammillatus zone at Ivö Klack, both in the Kristianstad Basin of NE Skåne. Numerous, heavily calcified chelipeds were found within a restricted bed at Åsen that was rich in carbonate-cemented nodules. Based on the burrowing lifestyle of modern mud shrimps, we interpret these nodules as infilled burrow chambers. The low abundance of molluscs within the Protocallianassa beds is also consistent with analogous extant communities, indicating that a similar ecologically exclusive relationship ruled within the Late Cretaceous shallow marine ecosystems.

  • 29.
    Elgorriaga, Andrés
    et al.
    Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, Pabellón nº 2, Ciudad Universitaria, C1428EHA Buenos Aires, Argentina.
    Escapa, Ignacio
    Consejo Nacional de Investigaciones Científicas y Técnicas, Museo Paleontológico Egidio Feruglio, Avenida Fontana 140, U9100GYO Chubut, Argentina.
    Bomfleur, Benjamin
    Swedish Museum of Natural History, Department of Paleobiology.
    Cúneo, Rubén
    Consejo Nacional de Investigaciones Científicas y Técnicas, Museo Paleontológico Egidio Feruglio, Avenida Fontana 140, U9100GYO Chubut, Argentina.
    Ottone, Eduardo
    Instituto de Estudios Andinos Don Pablo Groeber-Consejo Nacional de Investigaciones Científicas y Técnicas, Departamento de Ciencias Geológicas, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, Pabellón n° 2, Ciudad Universitaria, C1428EHA Buenos Aires, Argentina.
    Reconstruction and phylogenetic significance of a new Equisetum Linnaeus species from the Lower Jurassic of Cerro Bayo (Chubut province, Argentina)2015In: Ameghiniana, ISSN 1851-8044, Vol. 52, p. 135-152Article in journal (Refereed)
    Abstract [en]

    We describe Equisetum dimorphum sp. nov. from the Lower Jurassic of Chubut Province, Patagonia, Argentina. This new species is based on fertile and vegetative remains preserved as impressions of stems, leaves, strobili, transversal sections of the stems showing their anatomy, and terminal pagoda-like structures. The fine-grained sedimentary matrix also preserved detailed impressions of epidermal features. The morphological characters allow a whole-plant reconstruction and assignment to Equisetum. Equisetum dimorphum sp. nov. shows a mosaic of morphological characters that are commonly present in other Mesozoic forms and representatives of the two extant Equisetum subgenera, e.g., sunken stomata and a blunt strobilus apex. Compared to other well-known Mesozoic equisetalean taxa, Equisetum dimorphum sp. nov. appears to be most closely related to a group of Jurassic Equisetum-like plants including Equisetum laterale Phillips and Equisetites ferganensis Seward. Additional evidence for the morphological stasis of the fertile and vegetative organs of extant horsetails is supplied with this new material, adding further support to the hypothesis that the extant horsetails are a successful group that has undergone only little morphological changeover time and that has been present, nearly worldwide, since Jurassic times.

  • 30.
    Ericson, Per G P
    Swedish Museum of Natural History, Research Division.
    Systematic relationships of the palaeogene family Presbyornithidae (Aves: Anseriformes)1997In: Zoological Journal of the Linnean Society, ISSN 0024-4082, E-ISSN 1096-3642, Vol. 121, no 4, p. 429-483Article in journal (Refereed)
    Abstract [en]

    The early Tertiary (Paleocene and Eocene) family Presbyornithidae is one of the most completely known group of fossil birds. Essentially all parts of the skeleton are represented in the fossil record, allowing a thorough analysis of the phylogenetic position of the family. Forty-two families of nonpasserine birds representing the orders Ciconiiformes, Anseriformes, Galliformes, Gruiformes and Charadriiformes, were included in a cladistic analysis of 71 skeletal characters. The previously suggested anseriform affinity of the Presbyornithidae was confirmed. Furthermore, the family proved to be closer to the Anatidae than to the Anhimidae or Anseranatidae. The many postcranial similarities with certain charadriiform birds as the Burhinidae, obviously are plesiomorphies. By this observation, a better undestanding of character evolution in nonpasserine skeletal morphology is gained. The often suggested close relationship of anseriform and galliform birds is not confirmed by osteology. Instead, the Anseriformes and the Phoenicopteridae form a monophyletic clade that is the sister to the remaining ciconiiform birds. This result renders the Ciconiiformes sensu Wetmore (1960) polyphyletic. (C) 1997 The Linnean Society of London.

  • 31. Fortelius, Mikael
    et al.
    Žliobaitė, Indre
    Kaya, Ferhat
    Bibi, Faysal
    Bobe, René
    Leakey, Louise
    Leakey, Meave
    Patterson, David
    Rannikko, Janina
    Werdelin, Lars
    Swedish Museum of Natural History, Department of Paleobiology.
    An ecometric analysis of the fossil mammal record of the Turkana Basin2016In: Philosophical Transactions of the Royal Society of London. Biological Sciences, ISSN 0962-8436, E-ISSN 1471-2970, Vol. 371, article id 20150232Article in journal (Refereed)
    Abstract [en]

    Although ecometric methods have been used to analyse fossil mammal faunas and environments of Eurasia and North America, such methods have not yet been applied to the rich fossil mammal record of eastern Africa. Here we report results from analysis of a combined dataset spanning east and west Turkana from Kenya between 7 and 1 million years ago (Ma). We provide temporally and spatially resolved estimates of temperature and precipitation and discuss their relationship to patterns of faunal change, and propose a new hypothesis to explain the lack of a temperature trend. We suggest that the regionally arid Turkana Basin may between 4 and 2 Ma have acted as a ‘species factory’, generating ecological adaptations in advance of the global trend. We show a persistent difference between the eastern and western sides of the Turkana Basin and suggest that the wetlands of the shallow eastern side could have provided additional humidity to the terrestrial ecosystems. Pending further research, a transient episode of faunal change centred at the time of the KBS Member (1.87–1.53 Ma), may be equally plausibly attributed to climate change or to a top-down ecological cascade initiated by the entry of technologically sophisticated humans.

  • 32.
    Fregola, Rosa Anna
    et al.
    University of Bari.
    Skogby, Henrik
    Swedish Museum of Natural History, Department of Geology.
    Bosi, Ferdinando
    Swedish Museum of Natural History, Department of Geology.
    D'Ippolito, Veronica
    Sapienza University of Rome.
    Andreozzi, Giovanni
    Sapienza University of Rome.
    Hålenius, Ulf
    Swedish Museum of Natural History, Department of Geology.
    Optical absorption spectroscopy study of the causes for color variations in natural Fe-bearing gahnite: insights from iron valency and site distribution data.2014In: American Mineralogist, ISSN 0003-004X, E-ISSN 1945-3027, Vol. 99, p. 2187-2195Article in journal (Refereed)
  • 33.
    Friis, Else Marie
    et al.
    Swedish Museum of Natural History, Department of Paleobiology.
    Pedersen, Kaj Raunsgaard
    Department of Geoscience, University of Aarhus, Aarhus, Denmark.
    Crane, Peter R
    Yale School of Forestry and Environmental Studies, New Haven, CT, USA & Oak Spring Garden Foundation, Upperville, VA, USA.
    The emergence of core eudicots: new floral evidence from the earliest Late Cretaceous2016In: Proceedings of the Royal Society of London. Biological Sciences, ISSN 0962-8452, E-ISSN 1471-2954, Vol. 283, p. 1-9, article id 20161325Article in journal (Refereed)
    Abstract [en]

    Eudicots, the most diverse of the three major clades of living angiosperms, are first recognized in the latest Barremian–earliest Aptian. All Early Cretaceous forms appear to be related to species-poor lineages that diverged before the rise of core eudicots, which today comprise more than 70% of angiosperm species. Here, we report the discovery of a well-preserved flower, Caliciflora mauldinensis, from the earliest Late Cretaceous, with unequivocal core eudicot features, including five sepals, five petals and two whorls of stamens borne on the rim of a floral cup containing three free carpels. Pollen is tricolporate. Carpels mature into follicular fruitlets. This character combination suggests a phylogenetic position among rosids, but more specific assignment is precluded by complex patterns of character evolution among the very large number of potentially relevant extant taxa. The whorled floral organization is consistent with ideas that this stable pattern evolved early and was a prerequisite for more integrated patterns of floral architecture that evolved later. However, limited floral synorganization in Caliciflora and all earlier eudicot flowers recognized so far, calls into question hypotheses that substantial diversification of core eudicots had already occurred by the end of the Early Cretaceous.

  • 34.
    Gouramanis, Chris
    et al.
    Earth Observatory of Singapore, Nanyang Technological University, Singapore, 639798.
    McLoughlin, Stephen
    Swedish Museum of Natural History, Department of Paleobiology.
    Siluro-Devonian trace fossils from the Mereenie Sandstone, Kings Canyon, Watarrka National Park, Amadeus Basin, Northern Territory, Australia2016In: Alcheringa, ISSN 0311-5518, E-ISSN 1752-0754, Vol. 40, p. 118-128Article in journal (Refereed)
    Abstract [en]

    Nine trackways referable to the ichnogenus Diplichnites are preserved in the upper Silurian to Lower Devonian Mereenie Sandstone at Kings Canyon, Watarrka National Park, Northern Territory, Australia. Eight trackways are consistent with earlier descriptions of D. gouldi, and one trackway could not be assigned to an ichnospecies. The trackways are co-preserved with a range of sub-horizontal burrows referable to Beaconites and Taenidium, and several vertical burrows, surficial circular traces and a horizontal trail of uncertain identities. The ichnofossil assemblage highlights the diversity of animals present in the late Silurian to Lower Devonian paralic to fluvial environments of central Australia at the time of early colonization of the land’s surface. The assemblage is similar to ichnofaunas from coeval strata elsewhere in Australia and throughout Gondwana, and it highlights the potential of this region for further ichnological studies to elucidate the early stages of terrestrialization in the palaeoequatorial belt.

  • 35.
    Grimm, Guido
    et al.
    Swedish Museum of Natural History, Department of Paleobiology.
    Kapli, Paschalia
    3Natural History Museum of Crete and Biology Department, University of Crete, PO Box 2208, 71409 Heraklion, Crete, Greece.
    Bomfleur, Benjamin
    Swedish Museum of Natural History, Department of Paleobiology.
    McLoughlin, Stephen
    Swedish Museum of Natural History, Department of Paleobiology.
    Renner, Susanne
    Using more than the oldest fossils: Dating Osmundaceae with three Bayesian clock approaches2015In: Systematic Biology, ISSN 1063-5157, E-ISSN 1076-836X, Vol. 64, no 3, p. 396-405Article in journal (Refereed)
    Abstract [en]

    A major concern in molecular clock dating is how to use information from the fossil record to calibrate genetic distances from DNA sequences. Here we apply three Bayesian dating methods that differ in how calibration is achieved—“node dating” (ND) inBEAST, “total evidence” (TE) dating in MrBayes, and the “fossilized birth–death” (FBD) in FDPPDiv—to infer divergence times in the royal ferns. Osmundaceae have 16–17 species in four genera, two mainly in the Northern Hemisphere and two in South Africa and Australasia; they are the sister clade to the remaining leptosporangiate ferns. Their fossil record consists of at least 150 species in ∼17 genera. For ND, we used the five oldest fossils, whereas for TE and FBD dating, which do not require forcing fossils to nodes and thus can use more fossils,we included up to 36 rhizomes and frond compression/impression fossils, which for TE datingwere scored for 33morphological characters.We also subsampled 10%, 25%, and 50% of the 36 fossils to assess model sensitivity. FBD-derived divergence ages were generally greater than those inferred from ND; two of seven TE-derived ages agreed with FBD-obtained ages, the others were much younger or much older than ND or FBD ages. We prefer the FBD-derived ages because they best fit the Osmundales fossil record (including Triassic fossils not used in our study). Under the preferred model, the clade encompassing extant Osmundaceae (and many fossils) dates to the latest Paleozoic to Early Triassic; divergences of the extant species occurred during the Neogene. Under the assumption of constant speciation and extinction rates, the FBD approach yielded speciation and extinction rates that overlapped those obtained from just neontological data. However, FBD estimates of speciation and extinction are sensitive to violations in the assumption of continuous fossil sampling; therefore, these estimates should be treated with caution.

  • 36.
    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.

  • 37.
    Halamski, Adam
    Institute of Paleobiology, Polish Academy of Sciences.
    Vajda, Vivi
    Swedish Museum of Natural History, Department of Paleobiology. Department of Geology, Lund University, Sweden.
    Late Cretaceous (Campanian) leaf and palynoflora from southern Sweden2016In: Geological Society of London Special Publications, ISSN 0305-8719, Vol. 434, p. 207-230Article in journal (Refereed)
    Abstract [en]

    A Late Cretaceous (Campanian) leaf megaflora from the Vomb Trough in southern Skåne, Sweden, has been investigated on the basis of collections held at the Swedish Museum of Natural History. The main plant-bearing locality is Köpinge, but single specimens originate from Högestad, Ingelstorp, Rödmölla, Svenstorps mölla and Tosterup. The fossil flora is dominated by the angiosperm (eudicot) Debeya (Dewalquea) haldemiana (Debey ex de Saporta & Marion) Halamski. Other dicots are cf. Dryophyllum sp., Ettingshausenia sp., Rarytkinia? sp., Dicotylophyllum friesii (Nilsson) comb. nov. and Salicites wahlbergii (Nilsson) Hisinger. Conifers are represented by cf. Aachenia sp. (cone scales), Pagiophyllum sp. and Cyparissidium sp. (leaves). Single poorly preserved specimens of ferns and monocots have also been identified. The terrestrial palynomorphs (the focus herein) clearly link to the megaflora, although with different relative abundances. The fern spore Cyathidites dominates along with the conifer pollen Perinopollenites elatoides and Classopollis. Angiosperm pollen comprise up to 15% of the assemblage, represented by monocolpate, tricolpate and periporate pollen and the extinct Normapolles group. The spores in the kerogen residue show a thermal alteration index (TAI) of 2+. The flora probably represents mainly a coastal lowland Debeya/conifer forest, and is similar to approximately coeval assemblages from analogous palaeo-communities described from eastern Poland, western Ukraine and Westphalia.

  • 38. Hou, Lianhai
    et al.
    Ericson, Per G P
    Swedish Museum of Natural History, Research Division.
    A middle Eocene shorebird from China2002In: The Condor, ISSN 0010-5422, E-ISSN 1938-5129, Vol. 104, p. 896-899Article in journal (Refereed)
    Abstract [en]

    We describe a new species of shorebird, tentatively referred to the family Charadriidae, from the Huadian Formation (Middle Eocene) in Jilin Province, China. In general morphology the specimen closely matches that of an extant charadriid, and correspondsin size to the Killdeer (Charadrius vociferus). If correctly identified this is the oldest record of the Charadriidae. The Middle Eocene paleoenvironment of the Huadian region is thought to have resembled a subtropical swamp.

  • 39.
    Hryniewicz, Krzysztof
    et al.
    Institute of Paleobiology, Polish Academy of Sciences, Warszawa.
    Amano, Kazutaka
    Department of Geoscience, Joetsu University of Education, Niigata.
    Jenkins, Robert
    School of Natural System, College of Science and Engineering, Kanazawa University, Kanazawa City, Ishikawa .
    Kiel, Steffen
    Swedish Museum of Natural History, Department of Paleobiology.
    Thyasirid bivalves from Cretaceous and Paleogene cold seeps2017In: Acta Palaeontologica Polonica, ISSN 0567-7920, E-ISSN 1732-2421, Vol. 62, no 4, p. 705-728Article in journal (Refereed)
    Abstract [en]

    We present a systematic study of thyasirid bivalves from Cretaceous to Oligocene seep carbonates worldwide. Eleven species of thyasirid bivalves are identified belonging to three genera: Conchocele, Maorithyas, and Thyasira. Two species are new: Maorithyas humptulipsensis sp. nov. from middle Eocene seep carbonates in the Humptulips Formation, Washington State, USA, and Conchocele kiritachiensis sp. nov. from the late Eocene seep deposit at Kiritachi, Hokkaido, Japan. Two new combinations are provided: Conchocele townsendi (White, 1890) from Maastrichtian strata of the James Ross Basin, Antarctica, and Maorithyas folgeri (Wagner and Schilling, 1923) from Oligocene rocks from California, USA. Three species are left in open nomenclature. We show that thyasirids have Mesozoic origins and appear at seeps before appearing in “normal” marine environments. These data are interpreted as a record of seep origination of thyasirids, and their subsequent dispersal to non-seep environments. We discuss the age of origination of thyasirids in the context of the origin of the modern deep sea fauna and conclude that thyasirids could have deep sea origins. This hypothesis is supported by the observed lack of influence of the Cretaceous and Paleogene Oceanic Anoxic Events on the main evolutionary lineages of the thyasirids, as seen in several other members of the deep sea fauna.

  • 40. Hübers, M
    et al.
    Bomfleur, B
    Krings, M
    Pott, C
    Swedish Museum of Natural History, Department of Paleobiology.
    Kerp, H
    A reappraisal of Mississippian (Tournaisian and Visean) adpression floras from central and northwestern Europe2014In: Zitteliana, Series A, ISSN 1612-412X, Vol. 54, p. 39-52Article in journal (Refereed)
    Abstract [en]

    Mississippian plant fossils are generally rare, and in central and northwestern Europe especially Tournaisian to middle Visean fossil floras are restricted to isolated occurrences. While sphenophytes and lycophytes generally are represented by only a few widespread and long-ranging taxa such as Archaeocalamites radiatus, Sphenophyllum tenerrimum and several species of Lepidodendropsis and Lepidodendron, Visean floras in particular show a remarkably high diversity of fern-like foliage, including filiform types (Rhodea, Diplotmema), forms with bipartite fronds (Sphenopteridium, Diplopteridium, Spathulopteris, Archaeopteridium), others with monopodial, pinnate fronds (Anisopteris, Fryopsis) and still others characterized by several-times pinnate fronds (e.g., Adiantites, Triphyllopteris, Sphenopteris, Neuropteris). Most of these leaf types have been interpreted as belonging to early seed ferns, whereas true ferns seem to have been rare or lacking in impression/compression floras. In the upper Visean, two types of plant assemblages can be distinguished, i.e., the northern Kohlenkalk-type and the south-eastern Kulm-type assemblage. Although several compression/impression taxa have been revised in recent years to provide a more uniform classification, additional parameters such as different modes of preservation and imprecise information on stratigraphic age hamper detailed interregional comparisons of Mississippian floras.

  • 41.
    Ivarsson, Magnus
    et al.
    Swedish Museum of Natural History, Department of Paleobiology.
    Bengtson, Stefan
    Swedish Museum of Natural History, Department of Paleobiology.
    Carlsson, Diana
    Swedish Museum of Natural History, Department of Paleobiology.
    Är magmatiska bergarterfossilförande?2017In: Geologiskt Forum, ISSN ISSN 1104-4721, no 94, p. 20-23Article, review/survey (Other (popular science, discussion, etc.))
    Abstract [sv]

    Förekomsten av fossil är lika starkt sammankopplad till sedimentära bergarter som magmatiska bergarter är till frånvaron av fossil. Detta har varit ett obestridbart faktum sedan geovetenskapernas gryning. Men nu börjar detta synsätt att ändra sig. Forskare vid Naturhistoriska riksmuseet utforskar ett fossilt arkiv som påträffas i sprickor och håligheter i magmatiska och vulkaniska bergarter. Detta kan spela stor roll framöver för studiet av djupbiosfären och det tidiga livet på jorden samt även för sökandet efter liv på Mars.

  • 42.
    Ivarsson, Magnus
    et al.
    Swedish Museum of Natural History, Department of Paleobiology. Nordic Center for Earth Evolution (NordCEE).
    Gustavsson, Lena
    Swedish Museum of Natural History, Department of Zoology.
    Hedenäs, Lars
    Swedish Museum of Natural History, Department of Botany.
    Kronestedt, Torbjörn
    Swedish Museum of Natural History, Department of Zoology.
    Lundberg, Johannes
    Swedish Museum of Natural History, Department of Botany.
    Norbäck Ivarsson, Lena
    Södertörn University.
    Sallstedt, Therese
    Swedish Museum of Natural History, Department of Paleobiology. Nordic Center for Earth Evolution (NordCEE).
    Scheuerer, Manuela
    Sweco Rail.
    Thureborn, Olle
    Stockholm University.
    Wedin, Mats
    Swedish Museum of Natural History, Department of Botany.
    Unikt ekosystem i tunnelbanan vid Kungsträdgården2017In: Fauna och flora : populär tidskrift för biologi, ISSN 0014-8903, Vol. 112, no 1, p. 2-9Article in journal (Other (popular science, discussion, etc.))
  • 43.
    JADWISZCZAK, Piotr
    et al.
    Institute of Biology, University of Bialystok, Bialystok, Poland;.
    Mörs, Thomas
    Swedish Museum of Natural History, Department of Paleobiology.
    An enigmatic fossil penguin from the Eocene of Antarctica2017In: Polar Research, ISSN 0800-0395, E-ISSN 1751-8369, Vol. 36, no 1, article id 1291086Article in journal (Refereed)
    Abstract [en]

    Tarsometatarsi are key skeletal elements in penguin palaeontology. They constitute, among others, type specimens of all 10 widely accepted species of fossil penguins from the Eocene La Meseta Formation on Seymour Island (Graham Land, Antarctic Peninsula). Here, we report on a recently collected large-sized tarsometatarsus from this formation that represents a new morphotype. We are convinced that the morphotype corresponds to a new species, but the material is too scarce for a taxonomic act. Undoubtedly, the bone discussed here is a valuable addition to our knowledge on diversity of early penguins.

  • 44.
    Kear, Benjamin
    et al.
    Museum of Evolution, Uppsala University.
    Lindgren, Johan
    Department of Geology, Lund University.
    Jörn Hurum, Jörn
    Natural History Museum, University of Oslo.
    Milan, Jesper
    Geomuseum Faxe/Østsjællands Museum.
    Vajda, Vivi
    Swedish Museum of Natural History, Department of Paleobiology. Department of Geology, Lund University, Sweden.
    An introduction to the Mesozoic biotas of Scandinavia and its Arctic territories2016In: Geological Society, London, Special Publications, ISSN ISSN 0305-8719, Vol. 434, p. 1-14Article in journal (Refereed)
    Abstract [en]

    The Mesozoic biotas of Scandinavia have been studied for nearly two centuries. However, the last 15 years have witnessed an explosive advance in research, most notably on the richly fossiliferous Triassic (Olenekian–Carnian) and Jurassic (Tithonian) Lagersta¨tten of the Norwegian Arctic Svalbard archipelago, Late Cretaceous (Campanian) Kristianstad Basin and Vomb Trough of Skåne in southern Sweden, and the UNESCO heritage site at Stevns Klint in Denmark – the latter constituting one of the most complete Cretaceous–Palaeogene (Maastrichtian–Danian) boundary sections known globally. Other internationally significant deposits include earliest (Induan) and latest Triassic (Norian–Rhaetian) strata from the Danish autonomous territory of Greenland, and the Early Jurassic (Sinemurian–Pliensbachian) to Early Cretaceous (Berriasian) rocks of southern Sweden and the Danish Baltic island of Bornholm, respectively. Marine palaeocommunities are especially well documented, and comprise prolific benthic macroinvertebrates, together with pelagic cephalopods, chondrichthyans, actinopterygians and aquatic amniotes (ichthyopterygians, sauropterygians and mosasauroids). Terrestrial plant remains (lycophytes, sphenophytes, ferns, pteridosperms, cycadophytes, bennettitaleans and ginkgoes), including exceptionally well-preserved carbonized flowers, are also world famous, and are occasionally associated with faunal traces such as temnospondyl amphibian bones and dinosaurian footprints. While this collective documented record is substantial, much still awaits discovery. Thus, Scandinavia and its Arctic territories represent some of the most exciting prospects for future insights into the spectacular history of Mesozoic life and environments.

  • 45.
    Kiel, Steffen
    Swedish Museum of Natural History, Department of Paleobiology.
    Reply to Smith et al.: Network analysis reveals connectivity patterns in the continuum of reducing ecosystems2017In: Proceedings of the Royal Society of London. Biological Sciences, ISSN 0962-8452, E-ISSN 1471-2954, Vol. 284, article id 20171644Article in journal (Refereed)
    Abstract [en]

    The role of whale falls in the connectivity among, and adaptation to, reducing ecosystems in the deep sea has been the matter of a long debate. Hydrothermal vents are the most extreme among the reducing habitats in terms of temperature, metal concentrations and in their geographical isolation, and it is hence thought that stepping stones are needed to reach them. As new types of reducing habitats are being discovered, they are now increasingly seen as a ‘continuum of reducing ecosystems’. Taking this concept seriously implies that any habitat type within this continuum could provide connectivity to any other. Thus rather than focusing just on whales, I will address the issues raised by Smith et al. in the context of the question ‘who provides connectivity with whom, and to which extent?’

  • 46.
    Kiel, Steffen
    Swedish Museum of Natural History, Department of Paleobiology.
    Using network analysis to trace the evolution of biogeography through geologic time: A case study2017In: Geology, ISSN 0091-7613, E-ISSN 1943-2682, Vol. 45, p. 711-714Article in journal (Refereed)
    Abstract [en]

    The biogeographic distribution of organisms has continuously changed through Earth’s

    history as plate tectonics changed the configurations of land masses, ocean basins, and climate

    zones. Yet, methods to investigate this dynamic through geologic time are limited. Here,

    network analysis is used to explore and to visualize the biogeographic history of brachiopods

    through the entire Triassic period. Many previously recognized biogeographic provinces are

    found, and in addition, the stratigraphic ranges of these provinces were identified. Provinces

    in the Tethys Ocean show the lowest degree of connectedness, which can be linked to higher

    evolutionary rates in this tropical ocean basin and possibly also to higher habitat heterogeneity.

    Stratigraphically, the Tethyan provinces are separated largely along the boundaries of

    the Early, Middle, and Late Triassic. This suggests that the events resulting in faunal changes

    among the index fossils used to define these sub-periods also affected the brachiopods. However,

    through the ~50 m.y. of the Triassic period, geographic proximity played a greater role

    in producing faunal similarity than proximity in geologic age. Thus network analysis is a

    viable tool to better understand the dynamic evolution of biogeography through geologic time.

  • 47.
    Kiel, Steffen
    et al.
    Swedish Museum of Natural History, Department of Paleobiology.
    Hansen, Bent
    Cenozoic methane-seep faunas of the Caribbean region2015In: PLoS ONE, ISSN 1932-6203, E-ISSN 1932-6203, Vol. 10, no 10, article id e0140788Article in journal (Refereed)
    Abstract [en]

    We report new examples of Cenozoic cold-seep communities from Colombia, Cuba, the Dominican Republic, Trinidad, and Venezuela, and attempt to improve the stratigraphic dating of Cenozoic Caribbean seep communities using strontium isotope stratigraphy. Two seep faunas are distinguished in Barbados: the late Eocene mudstone-hosted ‘Joes River fauna’ consists mainly of large lucinid bivalves and tall abyssochrysoid gastropods, and the early Miocene carbonate-hosted ‘Bath Cliffs fauna’ containing the vesicomyid Pleurophopsis, the mytilid Bathymodiolus and small gastropods. Two new Oligocene seep communities from the Sinú River basin in Colombia consist of lucinid bivalves including Elongatolucina, thyasirid and solemyid bivalves, and Pleurophopsis. A new early Miocene seep community from Cuba includes Pleurophopsis and the large lucinid Meganodontia. Strontium isotope stratigraphy suggests an Eocene age for the Cuban Elmira asphalt mine seep community, making it the oldest in the Caribbean region. A new basal Pliocene seep fauna from the Dominican Republic is characterized by the large lucinid Anodontia (Pegophysema). In Trinidad we distinguish two types of seep faunas: the mudstone-hosted Godineau River fauna consisting mainly of lucinid bivalves, and the limestone-hosted Freeman’s Bay fauna consisting chiefly of Pleurophopsis, Bathymodiolus, and small gastropods; they are all dated as late Miocene. Four new seep communities of Oligocene to Miocene age are reported from Venezuela. They consist mainly of large globular lucinid bivalves including Meganodontia, and moderately sized vesicomyid bivalves. After the late Miocene many large and typical ‘Cenozoic’ lucinid genera disappeared from the Caribbean seeps and are today known only from the central Indo-Pacific Ocean. We speculate that the increasingly oligotrophic conditions in the Caribbean Sea after the closure of the Isthmus of Panama in the Pliocene may have been unfavorable for such large lucinids because they are only facultative chemosymbiotic and need to derive a significant proportion of their nutrition from suspended organic matter.

  • 48.
    Kiel, Steffen
    et al.
    Swedish Museum of Natural History, Department of Paleobiology.
    Krystyn, Leopold
    Department of Palaeontology, Vienna University, 1090 Vienna, Austria.
    Demirtaş, Ferdi
    Department of Geological Engineering, Akdeniz University, 07058 Antalya, Turkey.
    Koşun, Erdal
    Department of Geological Engineering, Akdeniz University, 07058 Antalya, Turkey.
    Peckmann, Jörn
    Institute for Geology, Universität Hamburg, 20146 Hamburg, Germany.
    Late Triassic mollusk-dominated hydrocarbon-seep deposits from Turkey2017In: Geology, ISSN 0091-7613, E-ISSN 1943-2682, Vol. 44, p. 751-754Article in journal (Refereed)
    Abstract [en]

    Deep-sea hydrothermal vents and hydrocarbon seeps host unique ecosystems relying on geochemical energy rather than photosynthesis. Whereas the fossil and evolutionary history of these ecosystems is increasingly well known from the Cretaceous onward, their earlier history remains poorly understood and brachiopods are considered to have played a dominant role during the Paleozoic and Mesozoic. Here we report five new hydrocarbon-seep deposits from the Upper Triassic Kasımlar shales in southern Turkey. The pyritiferous seep limestones predominantly consist of 13C-depleted micrite with δ13C values as low as −10.4‰, and contain only sparse 13C-depleted rim cement (δ13C as low as −12.0‰), interpreted to result from the recrystallization of banded and botryoidal crystal aggregates of fibrous cement. The geologic ages of the studied seep deposits were determined as late Carnian and early Norian using conodonts. The associated fauna is dominated by modiomorphid and anomalodesmatan bivalves, and also includes a diversity of gastropods and the dimerelloid brachiopod Halorella. These faunal assemblages allow a comparison between seep faunas from the two major Triassic ocean basins—the present assemblages being from Tethys, and the only previously known examples being from eastern Panthalassa—and indicate that a cosmopolitan, seep-restricted fauna as in the present-day oceans has existed since the Late Triassic. With almost 20 species, the seep fauna of the Kasımlar shales approaches the diversity of Cretaceous to present-day seep faunas, further emphasizing the ecological similarity of seep faunas since the early Mesozoic. Our findings also highlight that brachiopods and bivalves had a more complex history of coexistence at seeps than currently appreciated.

  • 49.
    Kiel, Steffen
    et al.
    Swedish Museum of Natural History, Department of Paleobiology.
    Taviani, Marco
    Institute of Marine Sciences, Italian National Research Council, Via Gobetti 101, 40129 Bologna, Italy.
    Chemosymbiotic bivalves from Miocene methane-seep carbonates in Italy2017In: Journal of Paleontology, ISSN 0022-3360, E-ISSN 1937-2337, Vol. 91, p. 444-466Article in journal (Refereed)
    Abstract [en]

    Eleven species of chemosymbiotic bivalves are reported from middle to late Miocene methane seep deposits (‘Calcari a Lucina’) in the Italian Apennines, including seven new species and one new genus. The new species are Bathymodiolus (s.l.) moroniae and B. (s.l.) miomediterraneus among the Bathymodiolinae and Archivesica aharoni, A. apenninica, A. strigarum, and ‘Pliocardia’ italica among the Vesicomyidae; specimens from the middle Miocene of Deruta are reported as Archivesica aff. aharoni. Samiolus iohannesbaptistae new genus new species is introduced for an unusual mytilid with a commarginally ribbed surface, which might be the first non-bathymodiolin mytilid obligate to the seep environment. The two large lucinid species from which these deposits derived their informal name ‘Calcari a Lucina’ are identified as Meganodontia hoernea (Des Moulins, 1868) and Lucinoma perusina (Sacco, 1901). With Chanellaxinus sp., we report the first thyasirid from a Neogene deep-water seep deposit in Italy and the first fossil occurrence of this genus.

  • 50. Kriwet, Jürgen
    et al.
    Engelbrecht, Andrea
    Mörs, Thomas
    Swedish Museum of Natural History, Department of Paleobiology.
    Reguero, Marcelo
    Pfaff, Cathrin
    Ultimate Eocene (Priabonian) chondrichthyans (Holocephali, Elasmobranchii) of Antarctica2016In: Journal of Vertebrate Paleontology, ISSN 0272-4634, E-ISSN 1937-2809Article in journal (Refereed)
    Abstract [en]

    ABSTRACT—The Eocene La Meseta Formation on Seymour Island, Antarctic Peninsula, is known for its remarkable wealth of fossil remains of chondrichthyans and teleosts. Chondrichthyans seemingly were dominant elements in the Antarctic Paleogene fish fauna, but decreased in abundance from middle to late Eocene, during which time remains of bony fishes increase. This decline of chondrichthyans at the end of the Eocene generally is related to sudden cooling of seawater, reduction in shelf area, and increasing shelf depth due to the onset of the Antarctic thermal isolation. The last chondrichthyan records known so far include a chimeroid tooth plate from TELM 6 (Lutetian) and a single pristiophorid rostral spine from TELM 7 (Priabonian). Here, we present new chondrichthyan records of Squalus, Squatina, Pristiophorus, Striatolamia, Palaeohypotodus, Carcharocles, and Ischyodus from the upper parts of TELM 7 (Priabonian), including the first record of Carcharocles sokolovi from Antarctica. This assemblage suggests that chondrichthyans persisted much longer in Antarctic waters despite rather cool sea surface temperatures of approximately 5C. The final disappearance of chondrichthyans at the Eocene–Oligocene boundary concurs with abrupt ice sheet formation in Antarctica. Diversity patterns of chondrichthyans throughout the La Meseta Formation appear to be related to climatic conditions rather than plate tectonics.

123 1 - 50 of 128
CiteExportLink to result list
Permanent link
Cite
Citation style
  • apa
  • ieee
  • modern-language-association-8th-edition
  • vancouver
  • Other style
More styles
Language
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Other locale
More languages
Output format
  • html
  • text
  • asciidoc
  • rtf