• Quantified Aeolian Dune Changes on Mars Derived From Repeat Context Camera Images

      Davis, Joel; M. Grindrod, P; Boazman, Sarah; Vermeesch, P; Baird, T (American Geophysical Union (AGU), 2019-12-11)
      Aeolian systems are active across much of the surface of Mars and quantifying the activity of bedforms is important for understanding the modern and recent Martian environment. Recently, the migration rates and sand fluxes of dunes and ripples have been precisely measured using repeat High Resolution Imaging Science Experiment (HiRISE) images. However, the limited areal extent of HiRISE coverage means that only a small area can be targeted for repeat coverage. Context Camera (CTX) images, although lower in spatial resolution, have wider spatial coverage, meaning that dune migration can potentially be monitored over larger areas. We used time series, coregistered CTX images and digital elevation models to measure dune migration rates and sand fluxes at six sites: Nili Patera, Meroe Patera, two sites at Herschel crater, McLaughlin crater, and Hellespontus Montes. We observed dune displacement in the CTX images over long‐term baselines (7.5–11 Earth years; 4–6 Mars years). Bedform activity has previously been measured at all these sites using HiRISE, which we used to validate our results. Our dune migration rates (0.2–1.1 m/EY) and sand fluxes (2.4–11.6 m3 m−1 EY−1) compare well to measurements made with HiRISE. The use of CTX in monitoring dune migration has advantages (wider spatial coverage, faster processing time) and disadvantages (ripples not resolved, digital elevation model dune heights may be underestimates); the future combined use of HiRISE and CTX is likely to be beneficial.
    • Quantifying the Effect of Anthropogenic Climate Change on Calcifying Plankton

      Fox, L; Stukins, S; Hill, Thomas; Giles Miller, C (Springer Science and Business Media LLC, 2020-01-31)
      Widely regarded as an imminent threat to our oceans, ocean acidification has been documented in all oceanic basins. Projected changes in seawater chemistry will have catastrophic biotic effects due to ocean acidification hindering biogenic carbonate production, which will in turn lead to substantial changes in marine ecosystems. However, previous attempts to quantify the effect of acidification on planktonic calcifying organisms has relied on laboratory based studies with substantial methodological limitations. This has been overcome by comparing historic plankton tows from the seminal HMS Challenger Expedition (1872–1876) with the recent Tara Oceans expedition material (2009–2016). Nano CT-scans of selected equatorial Pacific Ocean planktonic foraminifera, have revealed that all modern specimens had up to 76% thinner shells than their historic counterparts. The “Challenger Revisited” project highlights the potential of historic ocean collections as a tool to investigate ocean acidification since the early Industrial Revolution. Further analyses of such biotic archives will enable researchers to quantify the effects of anthropogenic climate change across the globe.
    • Quijarroite, Cu6HgPb2Bi4Se12, a New Selenide from the El Dragόn Mine, Bolivia

      Foerster, H-J; Bindi, L; Grundmann, G; Stanley, Christopher (2016-12)
    • Quo Vadis Venomics? A Roadmap to Neglected Venomous Invertebrates

      von Reumont, B; Campbell, L; Jenner, R (2014-12)
    • R. V. Dingle Ostracod Collection: Natural History Museum, London

      Dingle, RV; Giles Miller, C; Jones, C (Copernicus Publications, 2012)
      The collection was donated to the Natural History Museum (NHM) between 2009 and 2011 and consists of 2534 slides. It comprises mainly marine ostracods of Jurassic to Holocene age from southern Africa (and its adjacent oceans), Antarctica and New Zealand. There is also a small collection of Quaternary non-marine ostracods from southwestern Africa, two sets of DSDP/ODP ostracods from the Southern Ocean, and one set of Cape Roberts Drilling Project (CRDP) ostracods from Victoria Land, East Antarctica. The individual slides in this collection have been computer registered. Further details of these can be found by inputting seach criteria based on information given in the paper to the NHM’s on-line catalogue at http://www.nhm.ac.uk/research-curation/collections/departmental-collections/palaeontology-collections/search/index.php.
    • Rapid mixing and short storage timescale in the magma dynamics of a steady-state volcano

      Petrone, CM; Braschi, E; Francalanci, L; Casalini, M; Tommasini, S (2018-06)
    • Rare earth elements (REE)—Minerals in the Silius fluorite vein system (Sardinia, Italy)

      Mondillo, N; Boni, M; Balassone, G; Spoleto, S; Stellato, F; Marino, A; Santoro, L; Spratt, J (2016-04)
    • Rare earth elements in phoscorites and carbonatites of the Devonian Kola Alkaline Province, Russia: Examples from Kovdor, Khibina, Vuoriyarvi and Turiy Mys complexes

      Zaitsev, AN; Terry Williams, C; Jeffries, T; Strekopytov, S; Moutte, J; Ivashchenkova, OV; Spratt, J; Petrov, SV; Wall, F; Seltmann, Reimar; et al. (Elsevier, 2014-09)
      he Devonian (ca. 385–360 Ma) Kola Alkaline Province includes 22 plutonic ultrabasic–alkaline complexes, some of which also contain carbonatites and rarely phoscorites. The latter are composite silicate–oxide–phosphate–carbonate rocks, occurring in close space-time genetic relations with various carbonatites. Several carbonatites types are recognized at Kola, including abundant calcite carbonatites (early- and late-stage), with subordinate amounts of late-stage dolomite carbonatites, and rarely magnesite, siderite and rhodochrosite carbonatites. In phoscorites and early-stage carbonatites the rare earth elements (REE) are distributed among the major minerals including calcite (up to 490 ppm), apatite (up to 4400 ppm in Kovdor and 3.5 wt.% REE2O3 in Khibina), and dolomite (up to 77 ppm), as well as accessory pyrochlore (up to 9.1 wt.% REE2O3) and zirconolite (up to 17.8 wt.% REE2O3). Late-stage carbonatites, at some localities, are strongly enriched in REE (up to 5.2 wt.% REE2O3 in Khibina) and the REE are major components in diverse major and minor minerals such as burbankite, carbocernaite, Ca- and Ba-fluocarbonates, ancylite and others. The rare earth minerals form two distinct mineral assemblages: primary (crystallized from a melt or carbohydrothermal fluid) and secondary (formed during metasomatic replacement). Stable (C–O) and radiogenic (Sr–Nd) isotopes data indicate that the REE minerals and their host calcite and/or dolomite have crystallized from a melt derived from the same mantle source and are co-genetic.
    • Re-Os dating of pyrite confirms an early diagenetic onset and extended duration of mineralization in the Irish Zn-Pb ore field

      Hnatyshin, D; Creaser, RA; Wilkinson, JJ; Gleeson, SA (2015-02-01)
      The Irish Midlands region contains one of the world’s largest hydrothermal Zn-Pb ore districts, but uncertainty exists in the timing of mineralization relative to host rock ages. Consequently, genetic models for ore formation are poorly constrained and remain controversial. Here we use Re-Os geochronology to show that ore-stage pyrite from the Lisheen deposit formed at 346.6 ± 3.0 Ma, shortly after host rock deposition. Pyrite from the Silvermines deposit returns an age of 334.0 ± 6.1 Ma, indicating that at least some mineralization occurred during later burial. These age determinations show that the much younger paleomagnetic ages reported for the Irish Zn-Pb deposits reflect remagnetization during the Variscan orogeny, a process that we suggest affects paleomagnetic dating more widely. The Re-Os ages overlap with the ages of lower Carboniferous volcanic rocks in the Midlands, which are the product of magmatism that has been invoked as the driving force for hydrothermal activity. The relatively low initial Os ratios for both Lisheen (0.253 ± 0.045) and Silvermines (0.453 ± 0.006) are compatible with derivation of Os from these magmas, or from the Caledonian basement that underlies the ore deposits.
    • Reading Trees

      Ebach, Malte C.; Williams, DM (2014-06-09)
    • A reassessment of the purported ankylosaurian dinosaur Bienosaurus lufengensis from the Lower Lufeng Formation of Yunnan, China

      Raven, TJ; Barrett, PM; Xu, X; Maidment, S (Polish Academy of Sciences, 2019-03-19)
      The earliest definitive ornithischian dinosaurs are from the Early Jurassic and are rare components of early dinosaur faunas. The Lower Lufeng Formation (Hettangian–Sinemurian) of Yunnan Province, China, has yielded a diverse Early Jurassic terrestrial vertebrate fauna. This includes several incomplete specimens have been referred to Ornithischia, including the type specimen of the thyreophoran “Tatisaurus” and other generically indeterminate material. The highly fragmentary Lufeng ornithischian Bienosaurus lufengensis was described briefly in 2001 and identified as an ankylosaurian dinosaur. Recent studies have cast doubt on this hypothesis, however, and given that the referral of Bienosaurus to Ankylosauria would result in an extensive ghost-lineage extending between it and the first definitive eurypodans (ankylosaurs + stegosaurs) in the Middle Jurassic, the holotype specimen is re-examined and re-described. We identify Bienosaurus as a probable thyreophoran dinosaur, although the fragmentary nature of the material and the absence of autapomorphies means that the specimen should be regarded as a nomen dubium.
    • Recommended best practices for plastic and litter ingestion studies in marine birds: Collection, processing, and reporting

      Provencher, JF; Borrelle, SB; Bond, AL; Lavers, JL; van Franeker, JA; Kühn, S; Hammer, S; Avery-Gomm, S; Mallory, ML (Canadian Science Publishing, 2019-05-09)
      Marine plastic pollution is an environmental contaminant of significant concern. There is a lack of consistency in sample collection and processing that continues to impede meta-analyses and largescale comparisons across time and space. This is true for most taxa, including seabirds, which are the most studied megafauna group with regards to plastic ingestion research. Consequently, it is difficult to evaluate the impacts and extent of plastic contamination in seabirds fully and accurately, and to make inferences about species for which we have little or no data. We provide a synthesized set of recommendations specific for seabirds and plastic ingestion studies that include best practices in relation to sample collection, processing, and reporting, as well as highlighting some “cross-cutting” methods. We include guidance for how carcasses, regurgitations, and pellets should be handled and treated to prevent cross-contamination, and a discussion of what size class of microplastics can be assessed in each sample type. Although we focus on marine bird samples, we also include standardized techniques to remove sediment and biological material that are generalizable to other taxa. Lastly, metrics and data presentation of ingested plastics are briefly reviewed in the context of seabird studies.
    • Reconstructing Colonization Dynamics of the Human Parasite Schistosoma mansoni following Anthropogenic Environmental Changes in Northwest Senegal

      Van den Broeck, F; Maes, GE; Larmuseau, MHD; Rollinson, D; Sy, I; Faye, D; Volckaert, FAM; Polman, K; Huyse, T; Correa-Oliveira, R (2015-08-14)
    • Reconstructing the Neanderthal brain using computational anatomy

      Kochiyama, T; Ogihara, N; Tanabe, HC; Kondo, O; Amano, H; Hasegawa, K; Suzuki, H; de Leon, MSP; Zollikofer, CPE; Bastir, M; et al. (2018-04-26)
    • Reconstruction of the diapsid ancestral genome permits chromosome evolution tracing in avian and non-avian dinosaurs

      O'Connor, RE; Romanov, MN; Kiazim, LG; Barrett, PM; Farré, M; Damas, J; Ferguson-Smith, M; Valenzuela, N; Larkin, DM; Griffin, DK (2018-05-21)
    • Rediscovery and redescription of Centrodora damoni (Girault) (Hymenoptera: Aphelinidae) from Australia, an egg parasitoid of Gonipterus spp (Coleoptera: Curculionidae), after nearly a century

      Ward, S; Valente, C; Gonçalves, C; Polaszek, Andrew (2016-04-18)
      Background Centrodora is a relatively common and widespread genus of morphologically diverse species, and is the most polyphagous genus known within the Aphelinidae, attacking eggs of insects in addition to pupae of Diptera and Hymenoptera, and nymphs of Hemiptera (Polaszek 1991). There are currently about 60 valid species in the genus, but given its morphological and biological diversity, some elevation of species-groups and subgenera to genus-level might be useful in future. Centrodora is represented in Australia by twelve species (Noyes 2015). New information Centrodora damoni (Girault) is redescribed and diagnosed from recently collected specimens reared from the eucalyptus weevil Gonipterus sp. near scutellatus Gyllenhal (Coleoptera: Curculionidae) from Tasmania, Australia. A lectotype is designated from a syntype specimen.
    • Rediscovery of the syntypes of California Quail Tetrao californicus Shaw, 1798, and comments on the current labelling of the holotype of California Condor Vultur californianus Shaw, 1797

      Prys-Jones, Robert; Russell, D; Wright, S (British Ornithologists' Club, 2014-12)
      The two syntypes of California Quail Tetrao californicus Shaw, 1798, were deposited in the British Museum in the 1790s, but were last documented as present in the late 1860s and had subsequently been presumed no longer extant. In 2004, they were re-discovered in Notingham Natural History Museum, to which they must have been inadvertently passed as ‘duplicates’ in the late 1800s, and have now been returned to the Natural History Museum, Tring, on extended renewable loan. During research regarding these Archibald Menzies specimens, new insight was gained into hitherto confusing reference details on the label of his type specimen of California Condor Vultur californianus Shaw, 1797