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  • 1.
    ACOSTA HOSPITALECHE, Carolina
    et al.
    División Paleontología Vertebrados, Museo de La Plata, Paseo del Bosque s/n, B1900FWA, La Plata, Argentina.
    HAGSTRÖM, Jonas
    Swedish Museum of Natural History, Department of Paleobiology.
    REGUERO, Marcelo
    División Paleontología Vertebrados, Museo de La Plata, Paseo del Bosque s/n, B1900FWA, La Plata and Instituto Antártico Argentino (Dirección Nacional del Antártico), 25 de mayo 1143, San Martín, Argentina.
    Historical perspective of Otto Nordenskjöld´s Antarctic fossil penguin collection and Carl Wiman’s contribution2017In: Polar Record, ISSN 0032-2474, E-ISSN 1475-3057, Vol. 53, no 4, p. 364-375Article in journal (Refereed)
    Abstract [en]

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

  • 2. 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.

  • 3. Agustí, J.
    et al.
    Werdelin, LarsSwedish Museum of Natural History, Department of Paleobiology.
    Influence of climate on faunal evolution in the Quaternary of Europe1995Collection (editor) (Refereed)
  • 4. Alroy, John
    et al.
    Bernor, R. L.
    Fortelius, Mikael
    Werdelin, Lars
    Swedish Museum of Natural History, Department of Paleobiology.
    The MN System: regional or continental?1998In: Mitteilungen der Bayerischen Staatssammlung für Paläontologie und historische Geologie, Vol. 38, p. 243-258Article in journal (Refereed)
  • 5.
    Anderson, Heidi
    et al.
    Dorrigo, NSW, Australia.
    David J. Batten, David
    Manchester University.
    Cantrill, David
    National Herbarium of Victoria, Royal Botanic Gardens Melbourne.
    Cleal, Christopher
    Museum of Wales.
    Susanne Feist-Burkhardt, Susanne
    SFB Geological Consulting & Services, Odenwaldstrasse 18, D-64372 Ober-Ramstadt, Germany.
    Fensome, Robert
    Natural Resources Canada.
    Head, Martin
    Brock University, Canada.
    Herendeen, Patrick
    Chicago Botanuic Garden.
    Jaramillo, Carlos
    Smithsonian Institution.
    Kvaček, Jiří
    Czech National Museum, Prague.
    McLoughlin, Stephen
    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.

  • 6. Andersson, Ki
    et al.
    Norman, David
    Werdelin, Lars
    Swedish Museum of Natural History, Department of Paleobiology.
    Sabertoothed carnivores and the killing of large prey2011In: PLoS ONE, ISSN 1932-6203, E-ISSN 1932-6203, Vol. 6, no 10, p. e24971-Article in journal (Refereed)
    Abstract [en]

    Sabre-like canines clearly have the potential to inflict grievous wounds leading to massive blood loss and rapid death. Hypotheses concerning sabretooth killing modes include attack to soft parts such as the belly or throat, where biting deep is essential to generate strikes reaching major blood vessels. Sabretoothed carnivorans are widely interpreted as hunters of larger and more powerful prey than that of their present-day nonsabretoothed relatives. However, the precise functional advantage of the sabretooth bite, particularly in relation to prey size, is unknown. Here, we present a new point-to-point bite model and show that, for sabretooths, depth of the killing bite decreases dramatically with increasing prey size. The extended gape of sabretooths only results in considerable increase in bite depth when biting into prey with a radius of less than ~10 cm. For sabretooths, this size-reversed functional advantage suggests predation on species within a similar size range to those attacked by present-day carnivorans, rather than “megaherbivores” as previously believed. The development of the sabretooth condition appears to represent a shift in function and killing behaviour, rather than one in predator-prey relations. Furthermore, our results demonstrate how sabretoothed carnivorans are likely to have evolved along a functionally continuous trajectory: beginning as an extension of a jaw-powered killing bite, as adopted by present-day pantherine cats, followed by neck-powered biting and thereafter shifting to neck-powered shear-biting. We anticipate this new insight to be a starting point for detailed study of the evolution of pathways that encompass extreme specialisation, for example, understanding how neck-powered biting shifts into shear-biting and its significance for predator-prey interactions. We also expect that our model for point-to-point biting and bite depth estimations will yield new insights into the behaviours of a broad range of extinct predators including therocephalians (gorgonopsian + cynodont, sabretoothed mammal-like reptiles), sauropterygians (marine reptiles) and theropod dinosaurs.

  • 7. Andersson, Ki
    et al.
    Werdelin, Lars
    Swedish Museum of Natural History, Department of Paleobiology.
    Carnivora from the Late Miocene of Lantian, China2005In: Vertebrata PalAsiatica, Vol. 43, p. 256-271Article in journal (Refereed)
    Abstract [en]

    Sediments of the Bahe and Lantian formations, Lantian area, Shaanxi Province, China, have produced a large number of mammalian fossils. This Late Miocene sequence provides evidence for a period of major changes in the physical environment of the region. The carnivoran fossils are described and analyzed herein. The following species are present: lctitherium viverrinum, Hyaenictitherium cf . H. wongii and Adcrocuta eximia ( Hyaenidae) , cf. Metailurus major and cf. Metailurus parvulus ( Felidae) . Although a difference in the composition of the carnivoran fauna is noted towards the boundary between the Bahe Formation (lower) and Lantian Formation (upper), the cause of this is yet to be determined.

  • 8. BADAWY, AHMED SALAH
    et al.
    Mehlqvist, Kristina
    Vajda, Vivi
    Swedish Museum of Natural History, Department of Paleobiology.
    Ahlberg, Per
    Calner, Mikael
    Late Ordovician (Katian) spores in Sweden: oldest land plant remains from Baltica2014In: GFF, ISSN 1103-5897, E-ISSN 2000-0863, Vol. 136, no 1, p. 16-21Article in journal (Refereed)
    Abstract [en]

    A palynological study of the Ordovician–Silurian boundary (Katian–Rhuddanian) succession in the Röstaånga-1 drillcore, southern Sweden, has been performed. The lithology is dominated by mudstone and graptolitic shale, with subordinate limestone, formed in the deeper marine halo of southernBaltica. The palynological assemblages are dominated by marine microfossils, mainly chitinozoans and acritarchs. Sparse but well-preserved cryptospores, including Tetrahedraletes medinensis, Tetrahedraletes grayii and Pseudodyadospora sp., were encountered in the Lindegård Formation (late Katian–early Hirnantian), with the oldest record just above the first appearance of the graptolite species Dicellograptus complanatus. This represents the earliest record of early land plant spores from Sweden and possibly also from Baltica and implies that land plants had migrated to the palaeocontinent Baltica by at least the Late Ordovician.

  • 9.
    Bengtson, Stefan
    Swedish Museum of Natural History, Department of Paleobiology.
    Presentation of the 2010 Charles Schuchert Award of the Paleontological Society to Philip C. J. Donoghue.2011In: Journal of Paleontology, ISSN 0022-3360, E-ISSN 1937-2337, Journal of Paleontology, Vol. 85, no 5, p. 1015-Article in journal (Refereed)
    Abstract [en]

    LADIES AND gentlemen, friends and colleagues, the winner of the 2010 Charles Schuchert Award is Professor Philip Donoghue of the University of Bristol. In the natural progression of our personal lives, the transition from young snot to old fart is so gradual that one tends not to recognize it, least of all in oneself. Most of us— those further along in their careers— have passed through the stage of young, promising paleontologist to become middleaged promising paleontologists. Not so Phil Donoghue. I first met him when he was a graduate student at the University of Leicester. We got into a discussion about the nature of conodonts and certain pet ideas of mine that I had published. Phil did not agree with me so he went down in my book as a young snot. Soon thereafter, he published a ground-breaking, paradigm-changing paper, together with Peter Forey and Dick Aldridge, on the phylogenetic position of conodonts. Now, I realized that it was I who was the old fart. Phil had demonstrated that he had skipped the young-and-promising stage. He was, and is, young and delivering. Most people who start working on conodonts tend to remain with them. There is something about that mouth apparatus and the way in which it grabs hold of you. But Phil quickly tore himself loose from its grip. He quickly demonstrated an unquenchable zeal in attacking central issues in evolutionary paleontology, such as the origin of microstructures in teeth, the origin of teeth in jaws, the origin of jaws in vertebrates, the origin of vertebrates among animals, the origin of animals in the biosphere, and so on. I fear he will not stop until he has solved the question of the origin of life, the universe, and everything else. The breadth of questions he has already addressed is one aspect of Phil’s work. The diversity of tools he brings to bear on them is another. There is a lot of grinding powder under his fingernails, and lots of devo in his evo. After a sabbatical at the University of Bath, where he seems to have broken every rule of the Sabbath, he came out as a full-fledged molecular biologist, with RNA libraries at his fingertips. He is at the forefront in marrying data from living organisms with that from fossil taxa in phylogenetic analyses. Recently, he came out in defense of the paraphyletic stem group with arguments such that I have high hopes for his post-Schuchert development. Yes, paraphyletic groups are much more interesting than the monophyletic dead-ends called clades, although Phil of course refuses to call them groups. When Phil and some colleagues published a paper in Nature on the Cambrian fossil embryo Markuelia (again showing me wrong on a central issue), it caught the eye of Marco Stampanoni, a physicist who works at the Swiss Light Source (SLS) synchrotron near Zu¨ rich, in Switzerland. Marco had been developing methods of X-ray microtomography, using SLS beamlines. He contacted Phil with a proposal to collaborate, and Phil contacted me. Now, our collaboration based on this revolutionary technique, with Phil at the forefront, has opened our eyes to a huge amount of information to which we did not have access only a few years ago. Taphonomy is like the weather, people speak about it, but few do anything about it. But if you neglect it, you are in deep peril. Phil is much more concerned about taphonomy than most colleagues I know, and he does something about it. He started a project with embryologist Rudy Raff to determine how bacteria go about decomposing embryos in ways such that they are upgraded to exquisite fossils. He is engaging many colleagues, post-docs and students in the investigation of these processes and their end results. As a result, we are gaining insight into how bacteria can invade, devour and faithfully replicate intracellular features, and how different populations of bacteria play different roles in the process. An intriguing observation has emerged from Phil’s taphonomic work with Mark Purnell. Taphonomic degradation tends to bring about a stemward slippage of taxa in their apparent phylogenetic relationships, on account of sequential disappearance of preserved apomorphies. The general significance of this observation has still to be tested, but its potential importance for the phylogenetic analysis of fossils is obvious. Phil is leading an amazingly diverse and successful program in paleontology at the University of Bristol, permeated by his holistic approach and addressing everything from organismbased paleontology to molecular biology. Molecular, organismic, orgiastic paleontology—that’s the realm of Phil Donoghue. Mr. President, please hand the Schuchert Award for 2010 over to Phil. He thoroughly deserves it.

  • 10.
    Bengtson, Stefan
    Swedish Museum of Natural History, Department of Paleobiology.
    Presentation of the 2010 Paleontological Society Medal to Bruce Runnegar.2011In: Journal of Paleontology, ISSN 0022-3360, E-ISSN 1937-2337, Journal of Paleontology, Vol. 85, no 5, p. 1012-Article in journal (Refereed)
    Abstract [en]

    Ladies and gentlemen, friends and colleagues, the 2010 Paleontological Society Medal is awarded to Professor Bruce Runnegar of the University of California at Los Angeles. Preparing for this presentation, I got hold of a list of Bruce’s invited lectures, given during the past ten years. There are 86 titles on almost as many subjects. I will mention what these presentations were about, so you can get an impression of this Renaissance mind: Carbon isotopes and ocean evolution; Precambrian–Cambrian stratigraphy; Molecular evolution and the fossil record; Ediacaran organisms; Life on Mars; Oxygen and metazoan evolution; Orbital dynamics of the Earth–Moon system; Snowball Earth; Multiplated mollusks; Mass-independent fractionation of sulfur; Biomineralization; The Cambrian Explosion; Geobiology in the Archean; Cross-calibration of geological and astronomical time scales; Origins of biological complexity; Astrobiology of the Earth; Astrobiology of everything else; The Acraman impact of the Ediacaran; Biosignatures in ancient rocks; Microbial metabolism in the Early Archean. Now, most people can waffle about almost anything. A good teacher can read up on such topics and deliver useful lectures on them to students. But, as you will know if you are the least bit familiar with Bruce’s work, these are nearly all topics in fields where he has made startlingly innovative and pioneering contributions. Some would say that his most important contributions are missing from this list, such as molecular paleobiology, for example, or—if you prefer more tangible fossils—the systematics and evolution of Cambrian and Permian mollusks. But what is represented on the list is sufficient to document several brilliant careers in science: Bruce broke new ground in understanding the biomineralization processes of early mollusks by working with natural phosphatic replicas of the now vanished crystals of various species of calcium carbonate. He published a seminal set of papers on the evolution of the earliest mollusks, together with his longtime friend John Pojeta. And, as a leader of the astrobiology movement, Bruce has not only inspired everyone to start looking at life in a universal context, he has also brought his visions to life as Director of NASA’s Astrobiology Institute. It was in this context that Bruce was formally transformed from a U.S.-based Aussie to a full-fledged Australian– American (which is, I think, the politically correct term). In reference to molecular paleontology, I have some personal recollections. Bruce and I both have backgrounds as editors of paleontological journals. Bruce founded and for several years edited the successful Australasian journal Alcheringa, which is still going strong. Some of my first interactions with Bruce occurred in the 1970s, when he submitted manuscripts to Lethaia, of which I was an editor. One of my early forays was to question the number of authors of one of these manuscripts. I knew that no less than five authors of a single paper was excessive and confronted Bruce with this. It may have been the first time I really annoyed him, as he politely told me not to forget to turn my brain on, next time I wrote to him. Well, recently I saw an article in Nature with 230 authors, at which point it finally became clear to me that Bruce was ahead of his time. But back in those times I was a wee bit miffed, so when Bruce sent me a manuscript in which he estimated geological ages of major animal lineages using molecular clock techniques, I knew I could get my revenge. I sent the paper out for review by the sharpest molecular biologists of the day, smugly expecting to receive patronizing comments about paleontologists who should stick to their snail shells rather than pretending to be real scientists. No such luck. The reviews that came in were extravagant in their praise of the paper. Published in 1982, it predated by almost 15 years the avalanche of contributions that later came out on this topic. As usual, Bruce was ahead of the pack, but when others reached the spot where he had stood 15 years earlier, he wasn’t there anymore. Discrepancies between molecular and fossil data for a while seemed insurmountable, not to mention the discrepancies between different sets of molecular data and different sorts of analyses. But Bruce had inspired a bright set of younger biologists and paleontologists to refine their calculations. When the dust settled, one of those with whom Bruce had shared his spark, Kevin Peterson, was able to show that there is no significant conflict between the dates provided by fossils and by molecules. But I mentioned molecular paleontology. In 1986, Bruce published a seminal paper with just that title. In it he expressed his credo, thus: ‘‘palaeontologists should use all available sources of information to understand the evolution of life and its effect on the planet.’’ These are not empty words; they present a formidable challenge. Like all splendid visions, they stake out a direction rather than a goal. That it is possible to pursue this vision we see from the example set by this year’s Schuchert Award winner, Phil Donoghue, who together with Kevin Peterson and Roger Summons wrote a stimulating twenty-first century follow-up to Bruce’s earlier paper. But the foremost example is Bruce Runnegar himself. Here is a taste of the way in which his productive mind works. In 1982, Bruce used the anatomy and hypothesized physiology of the Ediacaran fossil Dickinsonia to estimate constraints for ambient oxygen levels in the Ediacaran atmosphere. This paper is much cited, and geochemists are only now catching up with him, developing geochemical proxies to test the hypothesis that a rising oxygen level was a trigger for the Cambrian Explosion, or, as Bruce so aptly put it, that one ‘‘ingredient, as in most explosives, may well have been a strong oxidising agent.’’ Finally, consider another example. In 1998, Bruce published a cladistic analysis of glaciogenic sediments, testing and corroborating the hypothesis that there were only two major Neoproterozoic glaciations, a result that still seems to stand. Who but Bruce would have thought of such a preposterous idea, using cladistics to resolve a stratigraphical conundrum? Bruce Runnegar has, over the years, formed collegial bonds with many scientists. The many younger people inspired by him include Phil Donoghue, now standing on Bruce’s shoulders. Bruce himself has stood on the shoulders of other giants, as he is quick to acknowledge. But, like Sir Isaac Newton, he has no reason to be bashful about his success, and I don’t think he is. The Paleontological Society Medal was really made for Bruce Runnegar, so please, Mr. President, give it to him!

  • 11.
    Bengtson, Stefan
    et al.
    Swedish Museum of Natural History, Department of Paleobiology.
    Collins, Desmond
    Chancelloriids of the Cambrian Burgess Shale2015In: Palaeontologia Electronica, ISSN 1935-3952, E-ISSN 1094-8074, Vol. 18, no 1, p. 1-67Article in journal (Refereed)
    Abstract [en]

    The cactus-like chancelloriids from the Middle Cambrian Burgess Shale are revised on the basis of Walcott’s (1920) original collections and new material containing several hundred specimens collected by Royal Ontario Museum field expeditions from 1975 to 2000. Walcott’s interpretation of chancelloriids as sponges was based on a misinterpretation of the dermal coelosclerites as embedded sponge-type spicules, an interpretation that further led to the lumping of three distinct taxa into one species, Chancelloria eros Walcott, 1920. The other two taxa are herein separated from C. eros and described as Allonnia tintinopsis n.sp. and Archiasterella coriacea n.sp., all belonging to the Family Chancelloriidae Walcott, 1920. Chancelloriids were sedentary animals, anchored to shells or lumps of debris in the muddy bottom, or to sponges, or to other chancelloriids. They had a radially symmetrical body and an apical orifice surrounded by a palisade of modified sclerites. Well-preserved integuments in Al. tintinopsis and Ar. coriacea do not show any ostium-like openings. Neither is there any evidence for internal organs, such as a gut. Partly narrowed specimens suggest that the body periodically contracted from the attached end to expel waste material from the body cavity. Chancelloriids were close in organization to cnidarians but shared the character of coelosclerites with the bilaterian halkieriids and siphogonuchitids. The taxon Coeloscleritophora is most likely paraphyletic.

  • 12.
    Bengtson, Stefan
    et al.
    Swedish Museum of Natural History, Department of Paleobiology.
    Cunningham, John A.
    Yin, Chongyu
    Donoghue, Philip C.J.
    University of Bristol.
    A merciful death for the “earliest bilaterian,” Vernanimalcula.2012In: Evolution and Development, ISSN 1520-541x, Vol. 14, no 5, p. 421-427Article in journal (Refereed)
    Abstract [en]

    Fossils described as Vernanimalcula guizhouena, from the nearly 600 million-year-old Doushantuo Formation in South China, have been interpreted as the remains of bilaterian animals. As such they would represent the oldest putative record of bilaterian animals in Earth history, and they have been invoked in debate over this formative episode of early animal evolution. However, this interpretation is fallacious. We review the evidential basis of the biological interpretation of Vernanimalcula, concluding that the structures key to animal identity are effects of mineralization that do not represent biological tissues, and, furthermore, that it is not possible to derive its anatomical reconstruction on the basis of the available evidence. There is no evidential basis for interpreting Vernanimalcula as an animal, let alone a bilaterian. The conclusions of evolutionary studies that have relied upon the bilaterian interpretation of Vernanimalcula must be called into question.

  • 13.
    Bengtson, Stefan
    et al.
    Swedish Museum of Natural History, Department of Paleobiology.
    Ivarsson, Magnus
    Swedish Museum of Natural History, Department of Paleobiology.
    Astolfo, Alberto
    Paul Scherrer Institute.
    Belivanova, Veneta
    Swedish Museum of Natural History, Department of Paleobiology.
    Broman, Curt
    Stockholm University.
    Marone, Federica
    Paul Scherrer Institute.
    Stampanoni, Marco
    ETH Zürich.
    Deep-biosphere consortium of fungi and prokaryotes in Eocene sub-seafloor basalts.2014In: Geobiology, ISSN 1472-4677, E-ISSN 1472-4669, Vol. 12, no 6, p. 489-496Article in journal (Refereed)
    Abstract [en]

    The deep biosphere of the subseafloor crust is believed to contain a significant part of Earth’s biomass, but because of the difficulties of directly observing the living organisms, its composition and ecology are poorly known. We report here a consortium of fossilized prokaryotic and eukaryotic microorganisms, occupying cavities in deep-drilled vesicular basalt from the Emperor Seamounts, Pacific Ocean, 67.5 meters below seafloor (mbsf). Fungal hyphae provide the framework on which prokaryote-like organisms are suspended like cobwebs and iron-oxidizing bacteria form microstromatolites (Frutexites). The spatial interrelationships show that the organisms were living at the same time in an integrated fashion, suggesting symbiotic interdependence. The community is contemporaneous with secondary mineralizations of calcite partly filling the cavities. The fungal hyphae frequently extend into the calcite, indicating that they were able to bore into the substrate through mineral dissolution. A symbiotic relationship with chemoautotrophs, as inferred for the observed consortium, may be a prerequisite for the eukaryotic colonization of crustal rocks. Fossils thus open a window to the extant as well as the ancient deep biosphere.

  • 14.
    Bengtson, Stefan
    et al.
    Swedish Museum of Natural History, Department of Paleobiology.
    Rasmussen, Birger
    Curtin University.
    Ivarsson, Magnus
    Swedish Museum of Natural History, Department of Paleobiology.
    Muhling, Janet
    Curtin University.
    Broman, Curt
    Stockholm University.
    Marone, Federica
    Stampanoni, Marco
    Bekker, Andrey
    University of California Riverside.
    Fungus-like mycelial fossils in 2.4-billion-year-old vesicular basalt.2017In: Nature Ecology & Evolution, ISSN 2397-334X, Vol. 1, no 6, p. 1-6, article id 0141Article in journal (Refereed)
    Abstract [en]

    Fungi have recently been found to comprise a significant part of the deep biosphere in oceanic sediments and crustal rocks. Fossils occupying fractures and pores in Phanerozoic volcanics indicate that this habitat is at least 400 million years old, but its origin may be considerably older. A 2.4-billion-year-old basalt from the Palaeoproterozoic Ongeluk Formation in South Africa contains filamentous fossils in vesicles and fractures. The filaments form mycelium-like structures growing from a basal film attached to the internal rock surfaces. Filaments branch and anastomose, touch and entangle each other. They are indistinguishable from mycelial fossils found in similar deep-biosphere habitats in the Phanerozoic, where they are attributed to fungi on the basis of chemical and morphological similarities to living fungi. The Ongeluk fossils, however, are two to three times older than current age estimates of the fungal clade. Unless they represent an unknown branch of fungus-like organisms, the fossils imply that the fungal clade is considerably older than previously thought, and that fungal origin and early evolution may lie in the oceanic deep biosphere rather than on land. The Ongeluk discovery suggests that life has inhabited submarine volcanics for more than 2.4 billion years.

  • 15.
    Bengtson, Stefan
    et al.
    Swedish Museum of Natural History, Department of Paleobiology.
    Sallstedt, Therese
    Swedish Museum of Natural History, Department of Paleobiology.
    Belivanova, Veneta
    Swedish Museum of Natural History, Department of Paleobiology.
    Whitehouse, Martin
    Swedish Museum of Natural History, Department of Geology.
    Three-dimensional preservation of cellular and subcellular structures suggests 1.6 billion-year-old crown-group red algae2017In: PLoS biology, ISSN 1544-9173, E-ISSN 1545-7885, Vol. 15, no 3, p. 1-38, article id e2000735Article in journal (Refereed)
    Abstract [en]

    The ~1.6 Ga Tirohan Dolomite of the Lower Vindhyan in central India contains phosphatized stromatolitic microbialites. We report from there uniquely well-preserved fossils interpreted as probable crown-group rhodophytes (red algae). The filamentous form Rafatazmia chitrakootensis n. gen, n. sp. has uniserial rows of large cells and grows through diffusely distributed septation. Each cell has a centrally suspended, conspicuous rhomboidal disk interpreted as a pyrenoid. The septa between the cells have central structures that may represent pit connections and pit plugs. Another filamentous form, Denaricion mendax n. gen., n. sp., has coin-like cells reminiscent of those in large sulfur-oxidizing bacteria but much more recalcitrant than the liquid-vacuole-filled cells of the latter. There are also resemblances with oscillatoriacean cyanobacteria, although cell volumes in the latter are much smaller. The wider affinities of Denaricion are uncertain. Ramathallus lobatus n. gen., n. sp. is a lobate sessile alga with pseudoparenchymatous thallus, “cell fountains,” and apical growth, suggesting florideophycean affinity. If these inferences are correct, Rafatazmia and Ramathallus represent crown-group multicellular rhodophytes, antedating the oldest previously accepted red alga in the fossil record by about 400 million years.

  • 16.
    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.

  • 17.
    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)
  • 18. Bernor, R. L.
    et al.
    Fahlbusch, V.
    Andrews, P.
    De Bruijn, H.
    Fortelius, M.
    Rögl, F.
    Steininger, F. F.
    Werdelin, Lars
    Swedish Museum of Natural History, Department of Paleobiology.
    The evolution of western Eurasian Neogene faunas: a chronologic, systematic, biogeographic, and paleoenvironmental synthesis1996In: The Evolution of Western Eurasian Miocene Mammal Faunas / [ed] Bernor, R.L., Fahlbusch, V. & Mittmann, H.-W., New York: Columbia University Press, 1996, p. 449-469Chapter in book (Refereed)
  • 19. Bernor, R. L.
    et al.
    Kordos, L.
    Rook, L.
    Agustí, J. C.
    Andrews, P.
    Armour-Chelu, M.
    Begun, D. R.
    Cameron, D. W.
    Daxner-Höck, G.
    Bonis, L. de
    Ekart, D.
    Fessaha, N.
    Fortelius, M.
    Franzen, J.-L.
    Mihály Gasparik, M.
    Gentry, A. G.
    Heissig, K.
    Hernyak, G.
    Kaiser, T.
    Koufos, G. D.
    Krolopp, E.
    Jánossy, D.
    Llenas, M.
    Meszáros, L.
    Müller, P.
    Renne, P.
    Rocék, Z.
    Sen, S.
    Scott, R.
    Szyndlar, Z.
    Theobald, G.
    Topál, G.
    Werdelin, Lars
    Swedish Museum of Natural History, Department of Paleobiology.
    Ungar, P. S.
    Ziegler, R.
    Recent Advances on Multidisciplinary Research at Rudabánya, Late Miocene (MN9), Hungary: a compendium2004In: Palaeontographia Italica, Vol. 89, p. 3-36Article in journal (Refereed)
  • 20. Betts, Marissa, J.
    et al.
    Paterson, John, R.
    Jacquet, Sarah, M.
    Andrew, Anita S.
    Hall, Philip A.
    Jago, James, B.
    Jagodzinski, Elisabeth A.
    Preiss, Wolfgang V.
    Crowley, James L.
    Brougham, Tom
    Mathewson, Ciaran P.
    Garcia-Bellido, Diego C.
    Topper, Timothy, P.
    Skovsted, Christian
    Swedish Museum of Natural History, Department of Paleobiology.
    Brock, Glenn, A.
    Early Cambrian chronostratigraphy and geochronology of South Australia2018In: Earth-Science Reviews, ISSN 0012-8252, E-ISSN 1872-6828, Vol. 185, p. 498-543Article in journal (Refereed)
    Abstract [en]

    The most successful chronostratigraphic correlation methods enlist multiple proxies such as biostratigraphy and chemostratigraphy to constrain the timing of globally important bio- and geo-events. Here we present the first regional, high-resolution shelly fossil biostratigraphy integrated with δ13C chemostratigraphy (and corresponding δ18O data) from the traditional lower Cambrian (Terreneuvian and provisional Cambrian Series 2) of South Australia. The global ZHUCE, SHICE, positive excursions II and III and the CARE are captured in lower Cambrian successions from the Arrowie and Stansbury basins. The South Australian shelly fossil biostratigraphy has a consistent relationship with the δ13C results, bolstering interpretation, identification and correlation of the excursions. Positive excursion II straddles the boundary between the Kulparina rostrata and Micrina etheridgei zones, and the CARE straddles the boundary between the M. etheridgei and Dailyatia odyssei zones, peaking in the lower parts of the latter zone. New CA-TIMS zircon dates from the upper Hawker Group and Billy Creek Formation provide geochronologic calibration points for the upper D. odyssei Zone and corresponding chemostratigraphic curve, embedding the lower Cambrian successions from South Australia into a global chronostratigraphic context. This multi-proxy investigation demonstrates the power of integrated methods for developing regional biostratigraphic schemes and facilitating robust global correlation of lower Cambrian successions from South Australia (part of East Gondwana) with coeval terranes on other Cambrian palaeocontinents, including South and North China, Siberia, Laurentia, Avalonia and West Gondwana.

  • 21. Betts, Marissa, J.
    et al.
    Paterson, John, R.
    Jago, James, B.
    Jacquet, Sarah, M.
    Skovsted, Christian
    Swedish Museum of Natural History, Department of Paleobiology.
    Topper, Timothy, P.
    Brock, Glenn, A.
    A new lower Cambrian shelly fossil biostratigraphy for South Australia2016In: Gondwana Research, ISSN 1342-937X, E-ISSN 1878-0571, Vol. 36, p. 163-195Article in journal (Refereed)
    Abstract [en]

    Definition of early Cambrian chronostratigraphic boundaries is problematic with many subdivisions stillawaiting ratification. Integrated multi-proxy data from well-resolved regional-scale schemes are ultimately the key to resolving broader issues of global correlationwithin the Cambrian. In Australia, early Cambrian biostratigraphy has been based predominantly on trilobites. Phosphatic shelly fauna have great potential as biostratigraphic tools, especially in pre-trilobitic strata because they are widespread and readily preserved, but they have remained underutilised. Here we demonstrate their value in a new biostratigraphic scheme for the early Cambrian of South Australia using a diverse shelly fauna including tommotiids, brachiopods, molluscs and bradoriids. Biostratigraphic data are derived from ten measured stratigraphic sections across the Arrowie Basin, targeting Hawker Group carbonates including the Wilkawillina, Wirrapowie and Ajax limestones and the Mernmerna Formation. The stratigraphic ranges of shelly fossils are predictable and repeatable across the Arrowie Basin, allowing three discrete shelly biozones to be identified, spanning Terreneuvian, Stage 2 to Series 2, Stages 3–4. The Kulparina rostrata Zone (new) and part of the overlyingMicrina etheridgei Zone (new) are pre-trilobitic (predominantly Terreneuvian). The Cambrian Series 2, Stage 3 Dailyatia odyssei Zone (new) features a very diverse shelly fauna and will be described in detail in a separate publication. These zones provide robust means to correlate Terreneuvian–Series 2 successions in neighbouring coeval basins in Australia, particularly the Stansbury Basin. Wider correlation is possible throughout East Gondwana, and especially with South China.

  • 22. Betts, Marissa, J.
    et al.
    Paterson, John, R.
    Jago, James, B.
    Jacquet, Sarah, M.
    Skovsted, Christian
    Swedish Museum of Natural History, Department of Paleobiology.
    Topper, Timothy, P.
    Brock, Glenn, A.
    A new lower Cambrian shelly fossil biostratigraphy for South Australia:Reply2017In: Gondwana Research, ISSN 1342-937X, E-ISSN 1878-0571, Vol. 44, p. 262-264Article in journal (Refereed)
  • 23.
    Betts, Marissa, J.
    et al.
    Department of Biological Sciences, Macquarie University, Sydney, 2109, Australia.
    Paterson, John, R.
    Palaeoscience Research Centre, School of Environmental and Rural Science, University of New England, Armidale, New South Wales 2351, Australia.
    Jago, James, B.
    School of Natural and Built Environments, University of South Australia, Mawson Lakes, South Australia 5095, Australia.
    Jacquet, Sarah, M.
    Department of Biological Sciences, Macquarie University, Sydney, 2109, Australia.
    Skovsted, Christian
    Swedish Museum of Natural History, Department of Paleobiology.
    Topper, Timothy, P.
    Palaeoecosystems Group, Department of Earth Sciences, Durham University, Durham, DH1 3LE, UK.
    Brock, Glenn, A.
    Department of Biological Sciences, Macquarie University, Sydney, 2109, Australia.
    Global correlation of the early Cambrian of South Australia: Shelly faunaof the Dailyatia odyssei Zone2017In: Gondwana Research, ISSN 1342-937X, E-ISSN 1878-0571, Vol. 46, p. 240-279Article in journal (Refereed)
    Abstract [en]

    A lack of well resolved biostratigraphic data has prevented robust regional and global correlation of lower Cambriansuccessions from South Australia. A new early Cambrian biostratigraphy, based on data derived from 21measured stratigraphic sections and drill cores (11 described herein) reveals the abundance and diversity ofshelly fauna from the Arrowie Basin, and the value of early Cambrian “small shelly fossils” (SSF) for biostratigraphicstudies. Here we examine shelly fauna associated with the youngest of three recently establishedbiozones, the Dailyatia odyssei Taxon Range Zone (hereafter D. odyssei Zone), and their correlative potential.The D. odyssei Zone features a diverse suite of tommotiids, organophosphatic brachiopods, bradoriid arthropods,molluscs and phosphatic problematica. This fauna permits strong correlation (often at species-level) with othermajor early Cambrian terranes, particularly Antarctica, South China and Laurentia, and suggest a Cambrian Series2, Stages 3–4 age for the D. odyssei Zone. Bradoriids have proven to be useful biostratigraphic tools. Four newspeciesand three new genera are described herein: Acutobalteus sinuosus gen. et sp. nov., Eozhexiella adnyamathanha gen. etsp. nov., Manawarra jonesi gen. et sp. nov. and Mongolitubulus descensus sp. nov. The description of Eohadrotreta sp.cf. zhenbaensis represents the first occurrence of the acrotretoid brachiopod Eohadrotreta from Australia.

  • 24.
    Betts, Marissa J.
    et al.
    Macquarie University, Sydney, Australia.
    Topper, Timothy P.
    Geological Museum, Copenhagen.
    Valentine, James L.
    Macquarie University, Sydney, Australia.
    Skovsted, Christian
    Swedish Museum of Natural History, Department of Paleobiology.
    Brock, Glenn A.
    Macquarie university, Australia.
    A new early Cambrian bradoriid (Arthropoda) assemblage from the northern Flinders Ranges, South Australia2014In: Gondwana Research, ISSN 1342-937X, E-ISSN 1878-0571, Vol. 25, p. 420-437Article in journal (Refereed)
    Abstract [en]

    A new assemblage of early Cambrian bivalved arthropods (Bradoriida) is described from the Arrowie Syncline in the northern Flinders Ranges, South Australia. The well preserved, largely endemic fauna comprises a total of six taxa (including five new species): Jiucunella phaseloa sp. nov., Jixinlingella daimonikoa sp. nov., Mongolitubulus anthelios sp. nov., Neokunmingella moroensis sp. nov., Phasoia cf. spicata ( Öpik, 1968), and Sinskolutella cuspidata sp. nov. This assemblage is derived from a carbonate sedimentary package representing a high energy, shallow water archaeocyath-Renalcis biohermal facies of Terreneuvian, Stage 2 age which transitions up-section to a more restricted, low energy, intra-shelf lagoonal environment that correlates with a Cambrian Series 2, Stage 3 age. The new taxon J. phaseloa sp. nov., has a first appearance datum (FAD) in shallow water biohermal facies of the Hideaway Well Member of the Wilkawillina Limestone at a level 47 m below the FAD of Pelagiella subangulata which is taken to approximate the base of Series 2, Stage 3 in South Australia. Along with Liangshanella circumbolina, this makes J. phaseloa sp. nov. amongst the oldest bivalved arthropods in South Australia and potentially greater Gondwana. The presence of 25 bradoriid taxa from the early Cambrian of South Australia suggests East Gondwana represents a major centre of origin for the Bradoriida.

  • 25. 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.

  • 26. Bicknell, Russell D.C.
    et al.
    Paterson, John, R.
    Caron, Jean-Bernhard
    Skovsted, Christian
    Swedish Museum of Natural History, Department of Paleobiology.
    The gnathobasic spine microstructure of recent and Silurian chelicerates and the Cambrian artiopodan Sidneyia: Functional and evolutionary implications2018In: Arthropod structure & development, ISSN 1467-8039, E-ISSN 1873-5495, Vol. 47, p. 12-24Article in journal (Refereed)
    Abstract [en]

    Gnathobasic spines are located on the protopodal segments of the appendages of various euarthropod taxa, notably chelicerates. Although they are used to crush shells and masticate soft food items, the microstructure of these spines are relatively poorly known in both extant and extinct forms. Here we compare the gnathobasic spine microstructures of the Silurian eurypterid Eurypterus tetragonophthalmus from Estonia and the Cambrian artiopodan Sidneyia inexpectans from Canada with those of the Recent xiphosuran chelicerate Limulus polyphemus to infer potential variations in functional morphology through time. The thickened fibrous exocuticle in L. polyphemus spine tips enables effective prey mastication and shell crushing, while also reducing pressure on nerve endings that fill the spine cavities. The spine cuticle of E. tetragonophthalmus has a laminate structure and lacks the fibrous layers seen in L. polyphemus spines, suggesting that E. tetragonophthalmus may not have been capable of crushing thick shells, but a durophagous habit cannot be precluded. Conversely, the cuticle of S. inexpectans spines has asimilar fibrous microstructure to L. polyphemus, suggesting that S. inexpectans was a competent shell crusher. This conclusion is consistent with specimens showing preserved gut contents containing various shelly fragments. The shape and arrangement of the gnathobasic spines is similar for both L. polyphemusand S. inexpectans, with stouter spines in the posterior cephalothoracic or trunk appendages, respectively.This differentiation indicates that crushing occurs posteriorly, while the gnathobases on anterior appendages continue mastication and push food towards and into the mouth. The results of recent phylogenetic analyses that considered both modern and fossil euarthropod clades show that xiphosurans and eurypterids are united as crown-group euchelicerates, with S. inexpectans placed within more basalartiopodan clades. These relationships suggest that gnathobases with thickened fibrous exocuticle, if not homoplasious, may be plesiomorphic for chelicerates and deeper relatives within Arachnomorpha. This study shows that the gnathobasic spine microstructure best adapted for durophagy has remained remarkably constant since the Cambrian.

  • 27.
    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.

  • 28.
    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.

  • 29.
    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.

  • 30.
    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.

  • 31.
    Bomfleur, Benjamin
    et al.
    Swedish Museum of Natural History, Department of Paleobiology.
    McLoughlin, Stephen
    Swedish Museum of Natural History, Department of Paleobiology.
    Vajda, Vivi
    Lund University.
    Fossilized nuclei and chromosomes reveal 180 millionyears of genomic stasis in Royal Ferns2014In: Science, ISSN ISSN 0036-8075, Vol. 343, p. 1376-1377Article in journal (Refereed)
    Abstract [en]

    Rapidly permineralized fossils can provide exceptional insights into the evolution of life over geological time. Here, we present an exquisitely preserved, calcified stem of a royal fern (Osmundaceae) from Early Jurassic lahar deposits of Sweden in which authigenic mineral precipitation from hydrothermal brines occurred so rapidly that it preserved cytoplasm, cytosol granules, nuclei, and even chromosomes in various stages of cell division. Morphometric parameters of interphase nuclei match those of extant Osmundaceae, indicating that the genome size of these reputed “living fossils” has remained unchanged over at least 180 million years—a paramount example of evolutionary stasis.

  • 32.
    Bomfleur, Benjamin
    et al.
    Swedish Museum of Natural History, Department of Paleobiology.
    Mörs, Thomas
    Swedish Museum of Natural History, Department of Paleobiology.
    Ferraguti, Marco
    Dipartimento di Bioscienze, Universita` degli Studi di Milano, Milano, Italy.
    Reguero, Marcelo
    Divisio´n Paleontologı´a de Vertebrados, Museo de La Plata, La Plata, Argentina.
    McLoughlin, Stephen
    Swedish Museum of Natural History, Department of Paleobiology.
    Fossilized spermatozoa preserved in a 50-myr-old annelid cocoon from Antarctica2015In: Biology Letters, ISSN 1744-9561, E-ISSN 1744-957X, Vol. 11, no 20150431, p. 1-5Article in journal (Refereed)
    Abstract [en]

    The origin and evolution of clitellate annelids—earthworms, leeches and their relatives—is poorly understood, partly because body fossils of these delicate organisms are exceedingly rare. The distinctive egg cases (cocoons) of Clitellata, however, are relatively common in the fossil record, although their potential for phylogenetic studies has remained largely unexplored. Here, we report the remarkable discovery of fossilized spermatozoa preserved within the secreted wall layers of a 50-Myr-old clitellate cocoon from Antarctica, representing the oldest fossil animal sperm yet known. Sperm characters are highly informative for the classification of extant Annelida. The Antarctic fossil spermatozoa have several features that point to affinities with the peculiar, leech-like ‘crayfish worms’ (Branchiobdellida). We anticipate that systematic surveys of cocoon fossils coupled with advances in non-destructive analytical methods may open a new window into the evolution of minute, soft-bodied life forms that are otherwise only rarely observed in the fossil record.

  • 33.
    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)
  • 34.
    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.

  • 35.
    Bouchal, Johannes M.
    Swedish Museum of Natural History, Department of Paleobiology.
    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 1814-9359Article 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.

  • 36.
    Bouchal, Johannes M.
    Swedish Museum of Natural History, Department of Paleobiology.
    Zetter, Reinhard
    Grímsson, F.
    Akgün, Funda
    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 1879-0615Article 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

  • 37.
    Bouchal, Johannes M.
    Swedish Museum of Natural History, Department of Paleobiology.
    Zetter, Reinhard (Contributor)
    Pollen and spores of the uppermost Eocene Florissant Formation, Colorado: A combined light and scanning electron microscopy study2016In: Grana, Vol. 55, no 3, p. 179-245Article in journal (Refereed)
    Abstract [en]

    The uppermost Eocene Florissant Formation, Rocky Mountains, Colorado, has yielded numerous insect, vertebrate, and plant fossils. Three previous comprehensive palynological studies investigated sections of lacustrine deposits of the Florissant Formation and documented the response of plant communities to volcanic eruptive phases but overall found little change in plant composition throughout the investigated sections. These studies reported up to 150 pollen and spore phenotypes. In the present paper we used a taxonomic approach to the investigation of dispersed pollen and spores of the Florissant Formation. Sediment samples from the shale units containing macrofossils were investigated using light microscopy (LM) and scanning electron microscopy (SEM). The general picture of the palynoflora is in agreement with previous studies. However, the combined LM and SEM investigation provides important complementary information to previous LM studies. While a fairly large amount of previous pollen determinations could be confirmed, the purported taxonomic affinities of several pollen phenotypes need to be revised. For example, pollen referred to as Podocarpus or Podocarpidites sp. belongs to the Pinaceae Cathaya, Malus/Pyrus actually belongs to Dryadoideae, pollen of the form genus Boehlensipollis referred to as Proteaceae/Sapindaceae/Elaeagnaceae or Cardiospermum belongs to Sapindaceae but not to Cardiospermum, and pollen of Persicarioipollis sp. B with previously assumed affinities to Polygonaceae actually belongs to Thymelaeaceae. Pandaniidites and one type of Malvacipollis cannot be linked with Pandanaceae and Malvaceae. A few taxa are new records for Florissant (Ebenaceae: Diospyros; Mernispermaceae; Trochodendraceae: Tetracentron). In general, SEM investigations complement the LM palynological studies and improve the identification of dispersed pollen and spores and enable integration of data from dispersed fossil pollen into a wide range of comparative morphological, taxonomic, evolutionary, biogeographic, and phylogenetic studies.

  • 38.
    Bouchal, Johannes M.
    Swedish Museum of Natural History, Department of Paleobiology.
    The middle Miocene palynofloras of the Salihpaşalar lignite mine(Yatağan Basin, southwest Anatolia): environmental characterisationand comparison with palynofloras from adjacent basins2018In: Palaeobiodiversity and Palaeoenvironments, ISSN 1867-1594, E-ISSN 1867-1608Article in journal (Refereed)
    Abstract [en]

    As the third part of an ongoing investigation of middle Miocene palynofloras in the Yatağan Basin (YB), southwestern Anatolia, thepalynofloras of the Salihpaşalar lignite mine in the main YB were studied. Seven types of algal spores, aplanospores/zygospores orcysts, six types of lycophyte and fern spores, 12 types of gymnosperm pollen and 90 types of angiosperm pollen were identified. Of atotal of ca. 140 plant taxa described from the YB, over 10% are confined to the Salihpaşalar assemblage. Differences between coevalpalynofloras of the Sekköy Member might reflect changing or prograding depositional environments. A number of rare accessorialtaxa reflect these local differences: Pilularia, Valeriana, Drosera and Persicaria aff. amphibia only occur at Salihpaşalar and aretypical of shallow water or temporary ponds associated with a lake shore. Apart from this, all the palynofloras, originating from thelignite seams and overlying limnic limestones (uppermost Turgut and Sekköy Member), of the YB are strongly indicative of extensivewoody vegetation with a dominance of diverse Fagaceae and Pinaceae. In addition, a list comparing the well-documented YBpalynomorphs to morphologically similar palynomorphs of published late early to middle Miocene plant assemblages of westernAnatolian was compiled. Such a comparison reveals that in many instances different taxon names have been used to denote the sametaxa. Hence, resolving these synonymies is a prerequisite of any meaningful comparison of palynofloras in the region.

  • 39.
    Bouchal, Johannes M.
    et al.
    Swedish Museum of Natural History, Department of Paleobiology.
    Denk, Thomas
    An overview of the palynoflora of the Miocene Yatağan basin, Turkey2014Conference paper (Other academic)
    Abstract [en]

    The palynoflora of the lignite strip mines of the Yatağan basin, located in the Muğla province of western Turkey, is the focus of this study. Samples were taken from the Eskihisar, Salihpasalar and Tinaz mines. In the Yatağan basin two Miocene formations, formed from river and lake deposits, Eskihisar Formation (middle Miocene) and Yatağan Formation (late Miocene) have been designated. Both show a general lithology consisting of conglomerate, sandstone, claystone, limestone and tuffite, the mined/excavated lignite bearing strata are restricted to the Eskihisar Formation.

    Until now, pollen from the Yatağan basin has mostly been described according to conventional morphological nomenclature, using light microscopy (LM) only. In this study, the same individual pollen grains are investigated by using both, LM and scanning electron microscopy (SEM). The  high resolution pictographs allow a higher taxonomic resolution.

    The rich palynoflora (Table 1) is comprised of diverse spores (at least nine morphotypes), gymnosperm pollen from Cupressaceae, Gnetales, Pinaceae, and angiosperm pollen from Poaceae, Typhaceae, Altingiaceae,  Amaranthaceae (Chenopodieae), Anacardiaceae, Apiaceae, Betulaceae, Buxaceae, Caprifoliaceae (Dipsacoideae, Lonicera) Caryophyllaceae, Compositae (Asteroideae, Cichoriodeae), Cornaceae, Eucommiaceae, Fabaceae, Fagaceae (Fagus, Quercus, Trigonobalanopsis) Geraniaceae, Juglandaceae, Malvaceae, Myricaceae, Nymphaeaceae, Oleaceae, Palmae, Plumbaginaceae (Armeria, Plumbago), Polygonaceae (Rumex), Salicaceae, Sapindaceae (Acer), Smilacaceae, and Ulmaceae (Cedrelospermum, Ulmus, Zelkova).

  • 40.
    Bouchal, Johannes M.
    et al.
    Swedish Museum of Natural History, Department of Paleobiology.
    Denk, Thomas
    Swedish Museum of Natural History, Department of Paleobiology.
    Grímsson, F.
    Palynostratigraphical correlation of the excavated Miocene lignite seams of the Yatağan basin (Muğla Province, south-western Turkey)2016Conference paper (Other academic)
    Abstract [en]

    The excavated main lignite seams and overlying lacustrine sediments of the opencast mines Eskihisar, Salihpaşalar, and Tınaz, Muğla Province, south-western Turkey were investigated using a high taxonomic resolution palynological approach.

    The Eskihisar section comprises 47m and 56 samples of which 30 were usable for palynological analysis. The Tınaz section comprises 75 m and 29 samples of which 15 were usable for palynological analysis. Finally, the Salihpaşalar section comprises 25 m and 26 samples of which 16 were usable for palynological analysis. The age of the palynological sections is middle to late Miocene based on radiometric dating and vertebrate fossils.

     

    In order to investigate dispersed pollen and spores and their botanical affinities a combined light microscopy and scanning electron microscopy approach was used. The rich palynoflora comprises seven types of algal cysts (Botryococcus, Zygnemataceae), seventeen spore types (Lycopsida, Marsileaceae, Osmundaceae, Pteridaceae, Polypodiaceae), 14 types of gymnosperm pollen (Ephedraceae, Cupressaceae, Pinaceae), five types of monocotyledone pollen (Poaceae, Typhaceae) and ca 90 dicotyledone pollen types (Altingiaceae, Amaranthaceae, Anacardiaceae, Apiaceae, Aquifoliaceae, Asteraceae, Betulaceae, Campanulaceae, Cannabaceae, Caprifoliaceae, Caryophyllaceae, Ericaceae, Eucommiaceae, Euphorbiaceae, Fabaceae, Fagaceae, Geraniaceae, Juglandaceae, Lamiaceae, Linaceae, Lythraceae, Malvaceae, Myricaceae, Oleaceae, Onagraceae, Plumbaginaceae, Polygonaceae, Ranunculaceae, Rosaceae, Salicaceae, Sapindaceae, Sapotaceae, Ulmaceae).

     

    The objectives of this investigation were (1) to evaluate whether the three palynological sections were deposited at the same time, and (2) to show regional vegetation differences within a single sedimentary basin.

     

    We found three general pollen zones corresponding to different sedimentary settings and palaeoenvironments. The first pollen zone was linked to lignite formation (swamp forest, fern spores, Alnus, Decodon). The second pollen zone reflects lacustrine conditions (Typhaceae) and surrounding hinterland vegetation dominated by Fagaceae. The third pollen zone is dominated by herbaceous taxa, whereas woody taxa are less diverse and less abundant.

     

    In general, the three palynological sections are congruent in reflecting distinct pollen zones. However main vegetation types may be represented by different dominating taxa (e. g. Alnus dominace in Eskihisar and Tınaz localities while absent in Salihpaşalar) and rare taxa may differ between localities.

     

    Our results demonstrate that in order to achieve a comprehensive understanding of environmental and vegetation conditions in a sedimentary basin, a single palynological section (locality) may not capture the entirety of environmental conditions and changes.

  • 41.
    Bouchal, Johannes M.
    et al.
    Swedish Museum of Natural History, Department of Paleobiology.
    Denk, Thomas
    Swedish Museum of Natural History, Department of Paleobiology.
    Grímsson, F.
    Zetter, Reinhard
    The middle Miocene palynoflora and palaeoenvironments of Eskihisar (Yatağan Basin, southwestern Anatolia):: a combined LM and SEM investigation2016In: Botanical journal of the Linnean Society, ISSN 0024-4074, E-ISSN 1095-8339, Vol. 182, no 1, p. 14-79Article in journal (Refereed)
    Abstract [en]

    Anatolia was a crossroads for mammal migration during the Miocene due to intermittent land connections between Africa and Anatolia and persisting warm conditions. Here, we investigated a palynological section from middle Miocene sediments of Eskihisar (southwestern Anatolia) in order to establish biogeographic links of the palynoflora and to infer the palaeoenvironment. Four algal palynomorphs, nine spore taxa, eight gymnosperms, three monocots, and 67 dicot pollen types were encountered and investigated using the “single grain method” that combines light microscopy and scanning electron microscopy. Two pollen zones reflect different phases of basin development. Zonal vegetation remained fairly stable across the section and reflects heterogeneous environments including broad-leaved deciduous forest, subtropical forest, and sclerophyllous and semi-evergreen oak forest. Conifers were accessory elements in the broad-leaved deciduous forest communities and replaced these at higher elevations. Some herbaceous taxa (Plumbaginaceae) indicate scattered occurrences of sandy and/or rocky soils. Biogeographic affinities are general Northern Hemispheric, North American, and East Asian as also suggested by the macro fossil record. Only two taxa provide potential biogeographic links with the African flora. This suggests that biome shifts of plant taxa between African subtropical /tropical biomes and Anatolian (western Eurasian) temperate forests and shrublands may have been rare in the middle Miocene.

  • 42.
    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.

  • 43.
    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.

  • 44.
    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).

  • 45. 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.

  • 46. 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.

  • 47. 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)
  • 48.
    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.

  • 49.
    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.

  • 50. Chaline, J.
    et al.
    Werdelin, LarsSwedish Museum of Natural History, Department of Paleobiology.
    Modes and Tempos of Evolution of Quaternary Mammals1993Collection (editor) (Refereed)
1234567 1 - 50 of 465
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