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  • Westbury, Michael, V
    et al.
    Hartmann, Stefanie
    Barlow, Axel
    Wiesel, Ingrid
    Leo, Viyanna
    Welch, Rebecca
    Parker, Daniel M.
    Sicks, Florian
    Ludwig, Arne
    Dalén, Love
    Swedish Museum of Natural History, Department of Bioinformatics and Genetics.
    Hofreiter, Michael
    Extended and Continuous Decline in Effective Population Size Results in Low Genomic Diversity in the World's Rarest Hyena Species, the Brown Hyena2018In: Molecular biology and evolution, ISSN 0737-4038, E-ISSN 1537-1719, Vol. 35, no 5, p. 1225-1237Article in journal (Refereed)
  • van der Valk, Tom
    et al.
    Sandoval-Castellanos, Edson
    Caillaud, Damien
    Ngobobo, Urbain
    Binyinyi, Escobar
    Nishuli, Radar
    Stoinski, Tara
    Gilissen, Emmanuel
    Sonet, Gontran
    Semal, Patrick
    Kalthoff, Daniela C.
    Swedish Museum of Natural History, Department of Zoology.
    Dalén, Love
    Guschanski, Katerina
    Significant loss of mitochondrial diversity within the last century due to extinction of peripheral populations in eastern gorillas2018In: Scientific Reports, ISSN 2045-2322, E-ISSN 2045-2322, Vol. 8, article id 6551Article in journal (Refereed)
  • Leasi, Francesca
    et al.
    Swedish Museum of Natural History, Department of Zoology. Department of Biology, Geology and Environmental Science, University of Tennessee at Chattanooga,.
    Sevigny, Joseph
    Hubbard Center for Genome Studies, Department of Molecular, Cellular, and Biomedical Sciences, University of New Hampshire.
    Laflamme, Eric
    Department of Mathematics, Plymouth State University.
    Artois, Tom
    Centre for Environmental Sciences, Hasselt University.
    Curini-Galletti, Marco
    Dipartimento di Medicina Veterinaria, University of Sassari,.
    Navarrete, Alberto
    Departmento de Sistemática y Ecología Acuática, El Colegio de la Frontera Sur, Unidad Chetumal.
    Di Domenico, Maikon
    Centro de Estudos do Mar, Universidade Federal do Paraná.
    Goetz, Freya
    Department of Invertebrate Zoology, Smithsonian National Museum of Natural History.
    Hall, Jeffrey
    Hubbard Center for Genome Studies, Department of Molecular, Cellular, and Biomedical Sciences, University of New Hampshire.
    Hochberg, Rick
    Department of Biological Science, University of Massachusetts Lowell.
    Jörger, Katharina
    Department of Biology, Ludwig-Maximilians–University of Munich.
    Jondelius, Ulf
    Swedish Museum of Natural History, Department of Zoology.
    Todaro, Antonio
    Department of Life Sciences, University of Modena & Reggio Emilia.
    Wirshing, Herman
    Department of Invertebrate Zoology, Smithsonian National Museum of Natural History.
    Norenburg, Jonathan
    Department of Invertebrate Zoology, Smithsonian National Museum of Natural History.
    Thomas, Kelley
    Hubbard Center for Genome Studies, Department of Molecular, Cellular, and Biomedical Sciences, University of New Hampshire.
    Biodiversity estimates and ecological interpretations of meiofaunal communities are biased by the taxonomic approach2018In: Communications Biology, ISSN ISSN 2399-3642, Vol. 112Article in journal (Refereed)
  • Hålenius, Ulf
    et al.
    Swedish Museum of Natural History, Department of Geology.
    Hatert, Frédéric
    Université de Liège, Belgium..
    Pasero, Marco
    Università di Pisa, Italy..
    Mills, Stuart J.
    Museum Victoria, Melbourne, Australia..
    IMA Commission on New Minerals, Nomenclature and Classification (CNMNC) Newsletter 462018In: European journal of mineralogy, ISSN 0935-1221, E-ISSN 1617-4011, Vol. 30, no 6, p. 181-189Article in journal (Other academic)
  • Murphy, Melissa
    et al.
    University of Oxford.
    Porcelli, Don
    University of Oxford.
    Pogge von Strandmann, Philip
    University College London.
    Hirst, Catherine
    Swedish Museum of Natural History, Department of Geology.
    Kutscher, Liselott
    Swedish Museum of Natural History, Department of Geology.
    Katchinoff, Joachim
    Yale University.
    Mörth, Carl-Magnus
    Stockholm University.
    Maximov, Trofim
    Institute for Biological Problems in the Cryolitic Zone, Yakutsk.
    Andersson, Per
    Swedish Museum of Natural History, Research Division.
    Tracingsilicate weathering processes in the permafrost-dominated Lena River watershedusing lithium isotopes2019In: Geochimica et Cosmochimica Acta, ISSN 0016-7037, E-ISSN 1872-9533, Vol. 245, p. 154-171Article in journal (Refereed)
    Abstract [en]

    Increasing global temperatures are causing widespread changes in the Arctic, including permafrost thawing and altered freshwater inputs and trace metal and carbon fluxes into the ocean and atmosphere. Changes in the permafrost active layer thickness can affect subsurface water flow paths and water-rock interaction times, and hence weathering processes. Riverine lithium isotope ratios (reported as δ7Li) are tracers of silicate weathering that are unaffected by biological uptake, redox, carbonate weathering and primary lithology. Here we use Li isotopes to examine silicate weathering processes in one of the largest Russian Arctic rivers: the Lena River in eastern Siberia. The Lena River watershed is a large multi-lithological catchment, underlain by continuous permafrost. An extensive dataset of dissolved Li isotopic compositions of waters from the Lena River main channel, two main tributaries (the Aldan and Viliui Rivers) and a range of smaller sub tributaries are presented from the post-spring flood/early-summer period at the onset of active layer development and enhanced water-rock interactions. The Lena River main channel (average δ7Lidiss ~19‰) has a slightly lower isotopic composition than the mean global average of 23‰ (Huh

    et al., 1998a). The greatest range of [Li] and δ7Lidiss are observed in catchments draining the south facing slopes of the Verkhoyansk Mountain Range. South-facing slopes in high-latitude, permafrost dominated regions are typically characterised by increased summer insolation and higher daytime temperatures relative to other slope aspects. The increased solar radiation on south-facing catchments promotes repeated freeze-thaw cycles, and contributes to more rapid melting of snow cover, warmer soils, and increased active layer thaw depths. The greater variability in δ7Li and [Li] in the south-facing rivers likely reflect the greater infiltration of melt water and enhanced water rock interactions within the active layer. A similar magnitude of isotopic fractionation is observed between the low-lying regions of the Central Siberian Plateau (and catchments draining into the Viliui River), and catchments draining the Verkhoyansk Mountain Range into the Aldan River. This is in contrast to global rivers in non permafrost terrains that drain high elevations or areas of rapid uplift, where high degrees of physical erosion promote dissolution of freshly exposed primary rock typically yielding low δ7Lidiss, and low lying regions exhibit high riverine δ7Li values resulting from greater water-rock interaction and formation of secondary mineral that fractionates Li isotopes. Overall, the range of Li concentrations and δ7Lidiss observed within the Lena River catchment are comparable to global rivers located in temperate and tropical regions. This suggests that cryogenic weathering features specific to permafrost regions (such as the continual exposure of fresh primary minerals due to seasonal freeze-thaw cycles, frost shattering and salt weathering), and climate (temperature and runoff), are not a dominant control on δ7Li variations. Despite vastly different climatic and weathering regimes, the same range of riverine δ7Li values globally suggests that the same processes govern Li geochemistry – that is, the balance between primary silicate mineral dissolution and the formation (or exchange with) secondary minerals. This has implications for the use of δ7Li as a palaeo weathering tracer for interpreting changes in past weathering regimes.

  • Stigenberg, Julia
    et al.
    Swedish Museum of Natural History, Department of Zoology.
    Zhang, Miles
    Sharanowski, Barbara
    Hope Meyer, Jacqueline
    Multilocus phylogeny of the parasitic wasps in the tribe Euphorini (Hymenoptera: Braconidae) with revised generic classifications2018In: PeerJ, ISSN 2167-8359, E-ISSN 2167-8359, article id 6:e4783Article in journal (Refereed)
    Abstract [en]

    Background. Parasitic wasps in the family Braconidae are important regulators of

    insect pests, particularly in forest and agroecosystems. Within Braconidae, wasps in the

    tribe Euphorini (Euphorinae) attack economically damaging plant bugs (Miridae) that

    are major pests of field and vegetable crops. However, the evolutionary relationships

    of this tribe have been historically problematic. Most generic concepts have been

    based on ambiguous morphological characters which often leads to misidentification,

    complicating their use in biological control.

    Methods. Using a combination of three genes (COI, 28S, and CAD) and 80 taxa

    collected worldwide, we conducted Bayesian inference using MrBayes, and maximum

    likelihood analyses using RAxML and IQ-Tree on individual gene trees as well as the

    concatenated dataset.

    Results. The monophyly of the tribe Euphorini and the two genera Peristenus and

    Leiophron were confirmed using maximum likelihood and Bayesian inference. The subgeneric

    classifications of Leiophron sensu lato were not supported, and the monotypic

    genus Mama was also not supported.

    Discussion. Euphoriella, Euphoriana, Euphorus, and Mama syn. n, have been synonymized

    under Leiophron. Mama mariae syn. n was placed as a junior synonym of

    Leiophron reclinator. The generic concepts of Peristenus and Leiophron were refined to

    reflect the updated phylogeny. Further we discuss the need for revising Euphorini given

    the number of undescribed species within the tribe.

  • Stigenberg, Julia
    Swedish Museum of Natural History, Department of Zoology.
    Review of the genus Townesilitus (Haeselbarth & Loan) in Sweden, with a molecular characterization.2017In: Entomologisk Tidskrift, ISSN 0013-886X, Vol. 138, no 2, p. 137-150Article in journal (Refereed)
    Abstract [en]

    The tribe Townesilitini (Braconidae, Euphorinae) includes the genera Townesilitus, Streblocera,

    Marshiella and Prochlithrophorus. In Sweden this tribe is represented by the genera

    Townesilitus and Streblocera. This paper explores the taxonomy of the genus Townesilitus

    in Sweden. One new species is described from Sweden, Townesilitus oelandicus sp.

    nov. and the species T. aemulus (Ruthe, 1856) is recorded for the first time for Sweden. All

    five Swedish species, T. aemulus (Ruthe, 1856), T. bicolor (Wesmael, 1835), T. deceptor

    (Wesmael, 1835), T. fulviceps (Ruthe, 1856) and T. oelandicus, are diagnosed both morphologically and molecularly. A key for the identification of these species is provided and

    a phylogenetic tree is presented as well as information on distribution and phenology for

    all five species occurring in Sweden.

  • Bergsten, Johannes
    et al.
    Swedish Museum of Natural History, Department of Zoology.
    Göthberg, Anders
    Johansson, Karolina
    Pettersson, Arne
    Burkart, Werner
    Burkart, Gudrun
    Entomologmötet på Gotland 2017: temaexkursion med fokus på vattenlevande skalbaggar, skinnbaggar och trollsländor i Äskåkersvät.2017In: Entomologisk Tidskrift, ISSN 0013-886X, Vol. 139, no 1, p. 39-49Article in journal (Refereed)
    Abstract [en]

    The yearly Swedish entomology meeting 2017 was organized by the local entomology

    society of Gotland, on the northern part of the Baltic island Gotland near Bunge, 4-6 August.

    One thematic excursion was focused on aquatic insects, especiallly aquatic beetles,

    bugs and dragonflies. A shallow pond, Äskåkersvät, with Characeae in an open grazed

    landscape with high natural values was studied. Äskåkersvät lies just adjacent to the larger

    area around lake Bästeträsk which is the focus of a pilot study evaluating its potential as

    a future national park. The pilot study is undertaken by Gotland County Administrative

    Board, the Swedish Environmental Protection Agency, Region Gotland and the Swedish

    Agency for Marine and Water Management. Here we give an annotated report of the 103

    species found: 69 species of water beetles (out of which 34 were Dytiscidae), 20 species

    of aquatic or semiaquatic bugs (out of which 10 were Corixidae), and 14 species of dragonflies.

    These include Hydrophilus piceus and H. aterrimus redlisted in Sweden (both as

    NT), and Dytiscus latissimus, globally redlisted (VU). We also noted the noble crayfish,

    Astacus astacus (redlisted as CR in Sweden) and the European medicinal leech Hirudo

    medicinalis (redlisted as NT globally). The blue emperor dragonfly (Anax imperator) was

    noted, a species first recorded from Gotland in 2002 and we present a graph on its increase

    and spreading on the island since. The number of species found in spite of a relatively

    modest collecting effort at a suboptimal time when many species may be in pupal stage out

    of water as witnessed by many teneral individuals, indicates a species rich locality with

    high natural value. The stoneworts (Characeae) vegetation certainly contributes to this, for

    instance vouched for by the occurrence of specialists as Haliplus confinis and H. obliquus

    whose larvae feed on stoneworts.

  • Sundberg, Henrik
    et al.
    Kruys, Åsa
    Bergsten, Johannes
    Swedish Museum of Natural History, Department of Zoology.
    Ekman, Stefan
    Position specificity in the genus Coreomyces (Laboulbeniomycetes, Ascomycota)2018In: Fungal Systematics and Evolution, ISSN 2589-3823, Vol. 1, p. 217-228Article in journal (Refereed)
    Abstract [en]

    To study position specificity in the insect-parasitic fungal genus Coreomyces (Laboulbeniaceae, Laboulbeniales),

    we sampled corixid hosts (Corixidae, Heteroptera) in southern Scandinavia. We detected Coreomyces thalli in five different

    positions on the hosts. Thalli from the various positions grouped in four distinct clusters in the resulting gene trees, distinctly

    so in the ITS and LSU of the nuclear ribosomal DNA, less so in the SSU of the nuclear ribosomal DNA and the mitochondrial

    ribosomal DNA. Thalli from the left side of abdomen grouped in a single cluster, and so did thalli from the ventral right side.

    Thalli in the mid-ventral position turned out to be a mix of three clades, while thalli growing dorsally grouped with thalli from

    the left and right abdominal clades. The mid-ventral and dorsal positions were found in male hosts only. The position on the left

    hemelytron was shared by members from two sister clades. Statistical analyses demonstrate a significant positive correlation

    between clade and position on the host, but also a weak correlation between host sex and clade membership. These results

    indicate that sex-of-host specificity may be a non-existent extreme in a continuum, where instead weak preferences for one

    host sex may turn out to be frequent.

  • Désamorè, Aurélie
    et al.
    Swedish Museum of Natural History, Department of Zoology.
    Laenen, Benjamin
    Miller, Kelly
    University of New Mexico.
    Bergsten, Johannes
    Swedish Museum of Natural History, Department of Zoology.
    Early burst in body size evolution is uncoupled from species diversification in diving beetles (Dytiscidae)2018In: Molecular Ecology, ISSN 0962-1083, E-ISSN 1365-294X, Vol. 27, no 4, p. 979-993Article in journal (Refereed)
    Abstract [en]

    Changes in morphology are often thought to be linked to changes in species diversification,

    which is expected to leave a signal of early burst (EB) in phenotypic traits.

    However, such signal is rarely recovered in empirical phylogenies, even for groups

    with well-known adaptive radiation. Using a comprehensive phylogenetic approach

    in Dytiscidae, which harbours ~4,300 species with as much as 50-fold variation in

    body size among them, we ask whether pattern of species diversification correlates

    with morphological evolution. Additionally, we test whether the large variation in

    body size is linked to habitat preference and whether the latter influences species

    turnover. We found, in sharp contrast to most animal groups, that Dytiscidae body

    size evolution follows an early-burst model with subsequent high phylogenetic conservatism.

    However, we found no evidence for associated shifts in species diversification,

    which point to an uncoupled evolution of morphology and species

    diversification. We recovered the ancestral habitat of Dytiscidae as lentic (standing

    water), with many transitions to lotic habitat (running water) that are concomitant

    to a decrease in body size. Finally, we found no evidence for difference in net diversification

    rates between habitats nor difference in turnover in lentic and lotic species.

    This result, together with recent findings in dragonflies, contrasts with some

    theoretical expectations of the habitat stability hypothesis. Thus, a thorough

    reassessment of the impact of dispersal, gene flow and range size on the speciation

    process is needed to fully encompass the evolutionary consequences of the lentic–

    lotic divide for freshwater fauna.

  • Sun, Xiaole
    et al.
    Stockholm University.
    Mörth, Carl-Magnus
    Stockholm University.
    Porcelli, Don
    Oxford University.
    Kutscher, Liselott
    Swedish Museum of Natural History, Department of Geology.
    Hirst, Catherine
    Swedish Museum of Natural History, Department of Geology.
    Murphy, Melissa
    Oxford University.
    Maximov, Trofim
    Institute for Biological Problems in the Cryolithozone, Yakusk.
    Petrov, Roman
    Institute for Natural Sciences of North Federal University, Yakutsk.
    Humborg, Christoph
    Stockholm University.
    Schmitt, Melanie
    Swedish Museum of Natural History, Department of Geology.
    Andersson, Per
    Swedish Museum of Natural History, Department of Geology.
    Stable Silicon Isotopic Compositions of the Lena River and its Tributaries: Implications for Silicon Delivery to the Arctic Ocean2018In: Geochimica et Cosmochimica Acta, ISSN 0016-7037, E-ISSN 1872-9533, Vol. 241, p. 120-133Article in journal (Refereed)
    Abstract [en]

    Silicon isotope values (δ30SiDSi) of dissolved silicon (DSi) have been analyzed in the Lena River and its tributaries, one of the largest Arctic watersheds in the world. The geographical and temporal variations of δ30SiDSi range from +0.39 to +1.86 ‰ with DSi concentrations from 34 to 121 μM. No obvious patterns of DSi concentrations and δ30SiDSi values were observed along over 200 km of the two major tributaries, the Viliui and Aldan Rivers. In summer, the variations of DSi concentrations and δ30SiDSi values in the water are either caused by biological uptake by higher plants and phytoplankton or by mixing of water masses carrying different DSi concentrations and δ30SiDSi values. DSi in tributaries from the Verkhoyansk Mountain Range seems to be associated with secondary clay formation that increased the δ30SiDSi values, while terrestrial biological production is likely more prevalent in controlling δ30SiDSi values in Central Siberian Plateau and Lena Amganski Inter-River Area. In winter, when soils were frozen, the δ30SiDSi values in the river appeared to be controlled by weathering and clay formation in deep intrapermafrost groundwater. During the spring flood, dissolved silicate materials and phytoliths were flushed from the upper thawed soils into rivers, which reset δ30SiDSi values to the values observed prior to the biological bloom in summer. The results indicate that the Si isotope values reflect the changing processes controlling Si outputs to the Lena River and to the Arctic Ocean between seasons. The annual average δ30SiDSi value of the Lena Si flux is calculated to be +0.86±0.3 ‰ using measured δ30SiDSi values from each season. Combined with the estimate of +1.6±0.25 ‰ for the Yenisey River, an updated δ30SiDSi value of the major river Si inputs to the Arctic Ocean is estimated to be +1.3±0.3 ‰. This value is expected to shift towards higher values in the future because of the impacts from a variety of biological and geochemical processes and sources under global warming.

     

  • Hybertsen, Frida
    et al.
    Swedish Museum of Natural History, Department of Paleobiology.
    Kiel, Steffen
    Swedish Museum of Natural History, Department of Paleobiology.
    A middle Eocene seep deposit with silicified fauna from the Humptulips Formation in western Washington State, USA2018In: Acta Palaeontologica Polonica, ISSN 0567-7920, E-ISSN 1732-2421, Vol. 63, p. 751-768Article in journal (Refereed)
  • Snape, Joshua
    et al.
    Swedish Museum of Natural History, Department of Geology.
    Curran, Natalie
    Whitehouse, Martin
    Swedish Museum of Natural History, Department of Geology.
    Nemchin, Alexander
    Joy, Katherine
    Hopkinson, Tom
    Mahesh, Anand
    Bellucci, Jeremy
    Swedish Museum of Natural History, Department of Geology.
    Kenny, Gavin
    Swedish Museum of Natural History, Department of Geology.
    Ancient volcanism on the Moon: Insights from Pb isotopes in the MIL 13317 and Kalahari 009 lunar meteorites2018In: Earth and Planetary Science Letters, ISSN 0012-821X, E-ISSN 1385-013X, Vol. 502, p. 84-95Article in journal (Refereed)
    Abstract [en]

    Lunar meteorites provide a potential opportunity to expand the study of ancient (>4000 Ma) basaltic volcanism on the Moon, of which there are only a few examples in the Apollo sample collection. Secondary Ion Mass Spectrometry (SIMS) was used to determine the Pb isotopic compositions of multiple mineral phases (Ca-phosphates, baddeleyite K-feldspar, K-rich glass and plagioclase) in two lunar meteorites, Miller Range (MIL) 13317 and Kalahari (Kal) 009. These data were used to calculate crystallisation ages of 4332 ± 2 Ma (95% confidence level) for basaltic clasts in MIL 13317, and 4369 ± 7 Ma (95% confidence level) for the monomict basaltic breccia Kal 009. From the analyses of the MIL 13317 basaltic clasts, it was possible to determine an initial Pb isotopic composition of the protolith from which the clasts originated, and infer a 238 U/204 Pb ratio (μ-value) of 850 ± 130 (2σ uncertainty) for the magmatic source of this basalt. This is lower than μ-values determined previously for KREEP-rich (an acronym for K, Rare Earth Elements and P) basalts, although analyses of other lithological components in the meteorite suggest the presence of a KREEP component in the regolith from which the breccia was formed and, therefore, a more probable origin for the meteorite on the lunar nearside. It was not possible to determine a similar initial Pb isotopic composition from the Kal 009 data, but previous studies of the meteorite have highlighted the very low concentrations of incompatible trace elements and proposed an origin on the farside of the Moon. Taken together, the data from these two meteorites provide more compelling evidence for widespread ancient volcanism on the Moon. Furthermore, the compositional differences between the basaltic materials in the meteorites provide evidence that this volcanism was not an isolated or localised occurrence, but happened in multiple locations on the Moon and at distinct times. In light of previous studies into early lunar magmatic evolution, these data also imply that basaltic volcanism commenced almost immediately after Lunar Magma Ocean (LMO) crystallisation, as defined by Nd, Hf and Pb model ages at about 4370 Ma.

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

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

  • Snape, Joshua
    et al.
    Swedish Museum of Natural History, Department of Geology.
    Davids, Bart
    Nemchin, Alexander
    Whitehouse, Martin
    Swedish Museum of Natural History, Department of Geology.
    Bellucci, Jeremy
    Swedish Museum of Natural History, Department of Geology.
    Constraining the timing and sources of volcanism at the Apollo 12 landing site using new Pb isotopic compositions and crystallisation ages2018In: Chemical Geology, ISSN 0009-2541, E-ISSN 1872-6836, Vol. 482, p. 101-112Article in journal (Refereed)
    Abstract [en]

    The basaltic suites collected at the Apollo 12 landing site have been interpreted as representing a stratigraphic sequence of volcanic flows emplaced in the Oceanus Procellarum region between approximately 3100–3300 Ma. This study presents Secondary Ion Mass Spectrometry (SIMS) Pb isotopic analyses of samples from each of the basaltic suites, which have been used to constrain precise crystallisation ages and initial Pb isotopic composi- tions. The new crystallisation ages are consistent with the three main basaltic suites (olivine, pigeonite and ilmenite) being emplaced over a period of approximately 60 million years, and the improved precision of these ages has made it possible to reinterpret the stratigraphic sequence of basalt flows underlying the Apollo 12 landing site. Contrary to previous studies, the three ilmenite basalts are determined as having the oldest ages (with a weighted average of 3187 ± 6 Ma; 2σ) and are, therefore, interpreted as representing the lowest unit in the sequence, underlying the olivine and pigeonite basalts (with an age range constrained by the oldest and youngest pigeonite basalts; 3176 ± 6 Ma and 3129 ± 10 Ma; 2σ). The initial Pb isotopic compositions have been compared with recalculated initial Sr and Nd isotopic compositions, and are consistent with the three main basaltic suites originating from magmatic sources that incorporated different proportions of a common primitive mafic cumulate and the residual trapped liquid fraction remaining after a majority of the lunar magma ocean had crystallised. Our data also demonstrate that the feldspathic basalt (12038) is unique, both in terms of its crys- tallisation age (3242 ± 13 Ma) and its derivation from a distinct mantle reservoir.

  • Bellucci, Jeremy
    et al.
    Swedish Museum of Natural History, Department of Geology.
    Nemchin, Alexander
    Whitehouse, Martin
    Swedish Museum of Natural History, Department of Geology.
    Snape, Joshua
    Swedish Museum of Natural History, Department of Geology.
    Bland, Phil
    Benedix, Gretchen
    Roszjar, Julia
    Pb evolution in the Martian mantle2018In: Earth and Planetary Science Letters, ISSN 0012-821X, E-ISSN 1385-013X, Vol. 485, p. 79-87Article in journal (Refereed)
    Abstract [en]

    The initial Pb compositions of one enriched shergottite, one intermediate shergottite, two depleted shergottites, and Nakhla have been measured by Secondary Ion Mass Spectrometry (SIMS). These values, in addition to data from previous studies using an identical analytical method performed on three enriched shergottites, ALH 84001, and Chassigny, are used to construct a unified and internally consistent model for the differentiation history of the Martian mantle and crystallization ages for Martian meteorites. The differentiation history of the shergottites and Nakhla/Chassigny are fundamentally different, which is in agreement with short-lived radiogenic isotope systematics. The initial Pb compositions of Nakhla/Chassigny are best explained by the late addition of a Pb-enriched component with a primitive, non-radiogenic composition. In contrast, the Pb isotopic compositions of the shergottite group indicate a relatively simple evolutionary history of the Martian mantle that can be modeled based on recent results from the Sm–Nd system. The shergottites have been linked to a single mantle differentiation event at 4504 Ma. Thus, the shergottite Pb isotopic model here reflects a two-stage history 1) pre-silicate differentiation (4504 Ma) and 2) post-silicate differentiation to the age of eruption (as determined by concordant radiogenic isochron ages). The μ-values (238U/204Pb) obtained for these two different stages of Pb growth are μ1 of 1.8 and a range of μ2 from 1.4–4.7, respectively. The μ1-value of 1.8 is in broad agreement with enstatite and ordinary chondrites and that proposed for proto Earth, suggesting this is the initial μ-value for inner Solar System bodies. When plotted against other source radiogenic isotopic variables (Sri, γ187Os, ε143Nd, and ε176Hf), the second stage mantle evolution range in observed mantle μ-values display excellent linear correlations (r2 > 0.85) and represent a spectrum of Martian mantle mixing-end members (depleted, intermediate, enriched).

  • Ge, Rongfeng
    et al.
    Wilde, Simon
    Nemchin, Alexander
    Whitehouse, Martin
    Swedish Museum of Natural History, Department of Geology.
    Bellucci, Jeremy
    Swedish Museum of Natural History, Department of Geology.
    Erickson, Timmons
    Frew, Adam
    Thern, Eric
    A 4463 Ma apparent zircon age from the Jack Hills (Western Australia) resulting from ancient Pb mobilization2018In: Geology, ISSN 0091-7613, E-ISSN 1943-2682, Vol. 46, no 4, p. 303-306Article in journal (Refereed)
    Abstract [en]

    Hadean (≥4.0 Ga) zircon grains provide the only direct record of the first half-billion years of Earth’s history. Determining accurate and precise crystallization ages of these ancient zircons is a prerequisite for any interpretation of crustal evolution, surface environment, and geodynamics on the early Earth, but this may be compromised by mobilization of radiogenic Pb due to subsequent thermal overprinting. Here we report a detrital zircon from the Jack Hills (Western Australia) with 4486–4425 Ma concordant ion microprobe ages that yield a concordia age of 4463 ± 17 Ma (2σ), the oldest zircon age recorded from Earth. However, scanning ion imaging reveals that this >4.4 Ga apparent age resulted from incorporation of micrometer-scale patches of unsupported radiogenic Pb with extremely high 207Pb/206Pb ratios and >4.5 Ga 207Pb/206Pb ages. Isotopic modeling demonstrates that these patches likely resulted from redistribution of radiogenic Pb in a ca. 4.3 Ga zircon during a ca. 3.8 Ga or older event. This highlights that even a concordia age can be spurious and should be carefully evaluated before being interpreted as the crystallization age of ancient zircon.

  • Bellucci, Jeremy
    et al.
    Swedish Museum of Natural History, Department of Geology.
    Nemchin, Alexander
    Swedish Museum of Natural History, Department of Geology.
    Whitehouse, Martin
    Swedish Museum of Natural History, Department of Geology.
    Ross, Kielman
    Swedish Museum of Natural History, Department of Geology.
    Snape, Joshua
    Swedish Museum of Natural History, Department of Geology.
    Pidgeon, Robert
    Geochronology of Hadean zircon grains from the Jack Hills, Western Australia constrained by quantitative scanning ion imaging2018In: Chemical Geology, ISSN 0009-2541, E-ISSN 1872-6836, Vol. 476, p. 469-480Article in journal (Refereed)
    Abstract [en]

    Five Hadean (> 4 Ga) aged zircon grains from the Jack Hills metasedimentary belt have been investigated by a secondary ion mass spectrometry scanning ion image technique. This technique has the ability to obtain accurate and precise full U-Pb systematics on a scale < 5 μm, as well as document the spatial distribution of U, Th and Pb. All five of the grains investigated here have complex cathodoluminescence patterns that correlate to different U, Th, and Pb concentration domains. The age determinations for these different chemical zones indicate multiple reworking events that are preserved in each grain and have affected the primary crystalized zircon on the scale of < 10 μm, smaller than conventional ion microprobe spot analyses. In comparison to the spot analyses performed on these grains, these new scanning ion images and age determinations indicate that almost half of the spot analyses have intersected several age and chemical domains in both fractured and unfractured parts of the individual crystals. Some of these unfractured, mixed domain spot analyses have concordant ages that are inaccurate. Thus, if the frequency of spot analyses intersecting mixed domains here is even close to representative of all other studies of the Jack Hills zircon population, it makes the interpretation of any trace element, Hf, or O isotopic data present in the literature tenuous. Lastly, all of the grains analysed here preserve at least two distinguishable 207Pb/206Pb ages. These ages are preserved in core-rim and/or complex internal textural relationships in unfractured domains. These secondary events took place at ca. 4.3, 4.2, 4.1, 4.0, 3.7, and 2.9 Ga, which are coincident with previously determined statistically robust age peaks present in this zircon population.

  • Skublov, Sergei
    et al.
    Krasotkina, Anna
    Makayev, Aleksandr
    Rizvanova, Nailya
    Kooijman, Ellen
    Swedish Museum of Natural History, Department of Geology.
    The first data on the U-Pb age (TIMS and LA-ICP-MS) of rutile from the Ichetju polymineral occurrence, The Middle Timan2018In: Journal of Mining Institute, Vol. 232, p. 357-363Article in journal (Refereed)
    Abstract [en]

    A study on the U-Pb age of rutile from the Ichetju polymineral occurrence has been done for the first time by LA-ICP-MS and TIMS methods. It was established that rutile originates from various sources with different ages (presumably, ca. 1000, 1660, 1860 and 1980 Ma), but all the rutile types have undergone a common thermal event at ca. 580 Ma. Obtained results are consistent with U-Pb zircon data for the Ichetju occurrence and the Pizhemskoe deposit. According to modern concepts, the closure temperature for the U-Pb system in rutile is higher than 500 С, which suggests fairly high-temperature conditions of the rutile hydrothermal transformation during the formation of the deposits in Riphean. Obviously, a placer hypothesis of formation of titanium deposits of the Middle Timan which is supported by a number of researchers does not explain such temperature of rutile alteration.

  • Glykou, Aikaterini
    et al.
    Eriksson, Gunilla
    Storå, J.
    Schmitt, Melanie
    Swedish Museum of Natural History, Department of Geology.
    Kooijman, Ellen
    Swedish Museum of Natural History, Department of Geology.
    Lidén, Kerstin
    Intra- and inter-tooth variation in strontium isotope ratios from prehistoric seals by laser ablation multi-collector inductively coupled plasma mass spectrometry2018In: Rapid Communications in Mass Spectrometry, ISSN 0951-4198, E-ISSN 1097-0231, Vol. 32, p. 1215-1224Article in journal (Refereed)
    Abstract [en]

    Rationale

    Strontium isotope ratios (87Sr/86Sr) in modern‐day marine environments are considered to be homogeneous (~0.7092). However, in the Baltic Sea, the Sr ratios are controlled by mixing seawater and continental drainage from major rivers discharging into the Baltic. This pilot study explores if variations in Sr can be detected in marine mammals from archaeological sites in the Baltic Sea.               

    Methods

    87Sr/86Sr ratios were measured in tooth enamel from three seal species by laser ablation multi‐collector inductively coupled plasma mass spectrometry (LA‐MC‐ICP‐MS). The method enables micro‐sampling of solid materials. This is the first time that the method has been applied to marine samples from archaeological collections.               

    Results

    The analyses showed inter‐tooth 87Sr/86Sr variation suggesting that different ratios can be detected in different regions of the Baltic Sea. Furthermore, the intra‐tooth variation suggests possible different geographic origin or seasonal movement of seals within different regions in the Baltic Sea through their lifetime.               

    Conclusions

    The method was successfully applied to archaeological marine samples showing that: (1) the 87Sr/86Sr ratio in marine environments is not uniform, (2) 87Sr/86Sr differences might reflect differences in ecology and life history of different seal species, and (3) archaeological mobility studies based on 87Sr/86Sr ratios in humans should therefore be evaluated together with diet reconstruction.

  • Drake, Henrik
    et al.
    Ivarsson, Magnus
    Tillberg, Mikael
    Whitehouse, Martin
    Swedish Museum of Natural History, Department of Geology.
    Kooijman, Ellen
    Swedish Museum of Natural History, Department of Geology.
    Ancient Microbial Activity in Deep Hydraulically Conductive Fracture Zones within the Forsmark Target Area for Geological Nuclear Waste Disposal, Sweden2018In: Geosciences, Vol. 8, no 211Article in journal (Refereed)
    Abstract [en]

    Recent studies reveal that organisms from all three domains of life—Archaea, Bacteria, and even Eukarya—can thrive under energy-poor, dark, and anoxic conditions at large depths in the fractured crystalline continental crust. There is a need for an increased understanding of the processes and lifeforms in this vast realm, for example, regarding the spatiotemporal extent and variability of the different processes in the crust. Here, we present a study that set out to detect signs of ancient microbial life in the Forsmark area—the target area for deep geological nuclear waste disposal in Sweden. Stable isotope compositions were determined with high spatial resolution analyses within mineral coatings, and mineralized remains of putative microorganisms were studied in several deep water-conducting fracture zones (down to 663 m depth), from which hydrochemical and gas data exist. Large isotopic variabilities of δ13Ccalcite (−36.2 to +20.2‰ V-PDB) and δ34Spyrite (−11.7 to +37.8‰ V-CDT) disclose discrete periods of methanogenesis, and potentially, anaerobic oxidation of methane and related microbial sulfate reduction at several depth intervals. Dominant calcite–water disequilibrium of δ18O and 87Sr/86Sr precludes abundant recent precipitation. Instead, the mineral coatings largely reflect an ancient archive of episodic microbial processes in the fracture system, which, according to our microscale Rb–Sr dating of co-genetic adularia and calcite, date back to the mid-Paleozoic. Potential Quaternary precipitation exists mainly at ~400 m depth in one of the boreholes, where mineral–water compositions corresponded.

  • Norén, Michael
    Swedish Museum of Natural History, Department of Zoology. FishBase.
    The enigmatic Betadevario ramachandrani (Teleostei: Cyprinidae: Danioninae): phylogenetic position resolved by mitogenome analysis, with remarks on the prevalence of chimeric mitogenomes in GenBank2018In: Cogent Biology, ISSN 2331-2025, Vol. 4, no 1, p. 1-8Article in journal (Refereed)
  • Malm, Tobias
    et al.
    Swedish Museum of Natural History, Department of Zoology.
    Rota, Jadranka
    Department of Biology, Lund University, Lund, Sweden.
    Chazot, Nicolas
    Department of Biology, Lund University, Lund, Sweden.
    Peña, Carlos
    HipLead, San Francisco, CA, United States of America.
    Wahlberg, Niklas
    Department of Biology, Lund University, Lund, Sweden.
    A simple method for data partitioning based on relative evolutionary rates2018In: PeerJ, ISSN 2167-8359, E-ISSN 2167-8359, p. 1-21, article id 6:e5498Article in journal (Refereed)
    Abstract [en]

    Background. Multiple studies have demonstrated that partitioning of molecular datasets is important in model-based phylogenetic analyses. Commonly, partitioning is done a priori based on some known properties of sequence evolution, e.g. differences in rate of evolution among codon positions of a protein-coding gene. Here we propose a new method for data partitioning based on relative evolutionary rates of the sites in the alignment of the dataset being analysed. The rates are inferred using the previously published Tree Independent Generation of Evolutionary Rates (TIGER), and the partitioning is conducted using our novel python script RatePartitions. We conducted simulations to assess the performance of our new method, and we applied it to eight published multi-locus phylogenetic datasets, representing different taxonomic ranks within the insect order Lepidoptera (butterflies and moths) and one phylogenomic dataset, which included ultra-conserved elements as well as introns.

    Methods. We used TIGER-rates to generate relative evolutionary rates for all sites in the alignments. Then, using RatePartitions, we partitioned the data into partitions based on their relative evolutionary rate. RatePartitions applies a simple formula that ensures a distribution of sites into partitions following the distribution of rates of the characters from the full dataset. This ensures that the invariable sites are placed in a partition with slowly evolving sites, avoiding the pitfalls of previously used methods, such as kmeans. Different partitioning strategies were evaluated using BIC scores as calculated by PartitionFinder.

    Results. Simulations did not highlight any misbehaviour of our partitioning approach, even under difficult parameter conditions or missing data. In all eight phylogenetic datasets, partitioning using TIGER-rates and RatePartitions was significantly better as measured by the BIC scores than other partitioning strategies, such as the commonly used partitioning by gene and codon position. We compared the resulting topologies and node support for these eight datasets as well as for the phylogenomic dataset.

    Discussion. We developed a new method of partitioning phylogenetic datasets without using any prior knowledge (e.g. DNA sequence evolution). This method is entirely based on the properties of the data being analysed and can be applied to DNA sequences (protein-coding, introns, ultra-conserved elements), protein sequences, as well as morphological characters. A likely explanation for why our method performs better than other tested partitioning strategies is that it accounts for the heterogeneity in the data to a much greater extent than when data are simply subdivided based on prior knowledge.

  • Kullander, Sven
    et al.
    Swedish Museum of Natural History, Department of Zoology.
    Norén, Michael
    Swedish Museum of Natural History, Department of Zoology.
    Rahman, MD. Mizanur
    University of Dhaka.
    Mollah, Abdur Rob
    University of Dhaka.
    Laubuka tenella, a new species of cyprinid fish from southeastern Bangladesh and southwestern Myanmar (Teleostei, Cyprinidae, Danioninae)2018In: ZooKeys, ISSN 1313-2989, E-ISSN 1313-2970, Vol. 742, p. 105-126Article in journal (Refereed)
    Abstract [en]

    Laubuka tenella is a new species characterized by the colour pattern, consisting of short dark verticalbars anteriorly on the side, and a dark lateral band posteriorly on the side, combined with a relativelyshort pelvic fin and 29–30 lateral-line scales. It is separated from other   analysed by minimum9 % uncorrected p-distance in the mitochondrial COI gene. The type series is composed of specimens from small streams in the Cox’s Bazar District in Bangladesh (the type locality), and the Thandwe River drainage in western Myanmar. Laubuka brahmaputraensis is strongly indicated to be a junior synonymof L. laubuca, the second known species of Laubuka in Bangladesh. Eustira ceylonensis, currently in thes ynonymy of Devario malabaricus, is a valid species of Laubuka.