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  • 101.
    Blom, H.
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Geovetenskapliga sektionen, Institutionen för geovetenskaper, Paleobiologi, Paleontologigruppen.
    Clack, J. A.
    Ahlberg, Per E.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för fysiologi och utvecklingsbiologi, Evolutionär organismbiologi.
    The forelimb of the Devonian tetrapod Ichthyostega.2003Ingår i: 51st symposium of vertebrate palaeontology and comparative anatomy, Oxford University Museum of Natural History, Oxford., 2003, s. 6-Konferensbidrag (Refereegranskat)
  • 102.
    Blom, H.
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Geovetenskapliga sektionen, Institutionen för geovetenskaper, Paleobiologi, Paleontologigruppen.
    Clack, J. A.
    Ahlberg, Per E.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för fysiologi och utvecklingsbiologi, Evolutionär organismbiologi.
    Friedman, M.
    Devonian vertebrates from East Greenland: a review of faunal composition and distribution2003Ingår i: The Gross Symposium 2. Advances in Palaeoichthyology. Riga, Latvia., 2003, s. 13-Konferensbidrag (Refereegranskat)
  • 103.
    Blom, H.
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Geovetenskapliga sektionen, Institutionen för geovetenskaper, Paleobiologi, Paleontologigruppen.
    Goujet, D.
    Thelodont scales from the Lower Devonian Red Bay Group, Spitsbergen.2000Ingår i: 9th International Symposium, Early Vertebrates/Lower Vertebrates. Flagstaff, Arizona., 2000, s. 2-Konferensbidrag (Refereegranskat)
  • 104.
    Blom, H.
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Geovetenskapliga sektionen, Institutionen för geovetenskaper, Paleobiologi, Paleontologigruppen.
    Märss, T.
    Miller, G. C.
    Affinity, classification and distribution of Silurian and lowermost Devonian birkeniid anaspid scales in the Circum-Arctic, Baltoscandia and Britain.1999Ingår i: Lower-Middle Palaeozoic Events Across the Circum-Arctic., 1999, s. 12-13Konferensbidrag (Refereegranskat)
  • 105.
    Blom, H.
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Geovetenskapliga sektionen, Institutionen för geovetenskaper, Paleobiologi, Paleontologigruppen.
    Märss, T.
    Miller, G. C.
    Silurian birkeniid anaspids from Britain.1999Ingår i: Palaeontological Association 43rd Annual Meeting. Manchester., 1999Konferensbidrag (Refereegranskat)
  • 106.
    Blom, Henning
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Geovetenskapliga sektionen, Institutionen för geovetenskaper, Paleobiologi, Paleontologigruppen.
    Vertebrate remains from the Chester Bjerg Formation (Late Silurian?), Hall Land, North Greenland.1995Självständigt arbete på avancerad nivå (masterexamen), 20 poäng / 30 hpStudentuppsats (Examensarbete)
  • 107.
    Blom, Henning
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Geovetenskapliga sektionen, Institutionen för geovetenskaper, Paleobiologi, Paleontologigruppen.
    Vertebrate remains from the Upper Silurian-Lower Devonian of North Greenland1998Licentiatavhandling, sammanläggning (Övrigt vetenskapligt)
  • 108.
    Bogolepova, Olga
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Geovetenskapliga sektionen, Institutionen för geovetenskaper. Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Geovetenskapliga sektionen, Institutionen för geovetenskaper, Paleobiologi. Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Geovetenskapliga sektionen, Institutionen för geovetenskaper, Geofysik.
    Gubanov, Alexander P.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Geovetenskapliga sektionen, Institutionen för geovetenskaper. Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Geovetenskapliga sektionen, Institutionen för geovetenskaper, Paleobiologi. Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Geovetenskapliga sektionen, Institutionen för geovetenskaper, Geofysik.
    Pease, Victoria L.
    Bohemian-type Silurian (Telychian) bivalves from Arctic Russia2005Ingår i: GFF, Vol. 127, nr 4, s. 247-252Artikel i tidskrift (Refereegranskat)
  • 109.
    Bordiga, Manuela
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Geovetenskapliga sektionen, Institutionen för geovetenskaper, Paleobiologi.
    Bartol, Milos
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Geovetenskapliga sektionen, Institutionen för geovetenskaper, Paleobiologi.
    Henderiks, Jorijntje
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Geovetenskapliga sektionen, Institutionen för geovetenskaper, Paleobiologi.
    Absolute nannofossil abundance estimates: quantifying the pros and cons of different techniques2015Ingår i: Revue de Micropaléontologie, Vol. 58, nr 3, s. 155-165Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    A quick and inexpensive method to determine absolute nannofossil abundance in deep sea sediments – the “drop” technique (modified dilution method) – was compared to two other available methods – the filtration and random settling techniques. All techniques rely on the same basic principle, under which a volume of known concentration (bulk sediment weight/mL) is distributed evenly over a known total area (glass slide or filter) to then count particles within a set of (randomly) selected fields of view. The three preparation techniques were also calibrated by spiking the samples with microbeads to approach the “real values” as closely as possible. Significant offsets in abundance estimates between methods mainly reflect bias due to the uneven distribution and/or loss of particles. We show that the drop technique is most consistent and accurate in estimating “real values” and offers similar or better reproducibility than the other techniques. The drop method also allows detection of the same trends with or without calibration with microbeads. The filtration method holds the risk to drastically underestimate absolute abundances, while the settling technique is demanding in terms of time and may suffer from advection processes. The composition of nannofossil assemblages can be reliably determined by any of the three different techniques.

  • 110. Bordiga, Manuela
    et al.
    Bartol, Milos
    Henderiks, Jorijntje
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Geovetenskapliga sektionen, Institutionen för geovetenskaper, Paleobiologi.
    Another drop in the ocean ... how to determine absolute coccolith abundance?2015Konferensbidrag (Övrigt vetenskapligt)
  • 111.
    Bordiga, Manuela
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Geovetenskapliga sektionen, Institutionen för geovetenskaper, Paleobiologi.
    Cobianchi, M
    Lupi, C
    Ziveri, Patrizia
    Henderiks, Jorijntje
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Geovetenskapliga sektionen, Institutionen för geovetenskaper, Paleobiologi.
    Calcareous nannofossils and ocean carbon cycle during the last 450 ka in the NW Pacific Ocean (Shatsky Rise)2013Konferensbidrag (Övrigt vetenskapligt)
  • 112.
    Bordiga, Manuela
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Geovetenskapliga sektionen, Institutionen för geovetenskaper, Paleobiologi.
    Cobianchi, Miriam
    Lupi, Claudia
    Pelosi, Nicola
    Venti, Nicholas L.
    Ziveri, Patrizia
    Coccolithophore carbonate during the last 450 ka in the NW Pacific Ocean (ODP site 1209B, Shatsky Rise)2014Ingår i: Journal of Quaternary Science, ISSN 0267-8179, E-ISSN 1099-1417, Vol. 29, nr 1, s. 57-69Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    This study focuses on Pleistocene-Holocene sediments from the Shatsky Rise (Ocean Drilling Program Site 1209B, NW Pacific Ocean). We quantify the contribution of calcite made by coccoliths in oceanic sediments, investigating the role of calcareous nannoplankton during the last 450 ka. Coccolith carbonate constitutes 60-90% of bulk carbonate. Coccolith carbonate accumulation rates (CARs) and CaCO3 fine fraction confirm that coccolithophores are major contributors to the carbonate export and accumulation. Primary productivity shows highest values from marine isotope stage (MIS) 12 to 8. Thereafter, although coccolith calcite content remains high, other sediment components, such as as foraminifera and biogenic opal, seem to be favored, perhaps related to an increase in fertilization by eolian dust. Our results demonstrate the important role of coccolithophore production and sedimentation on the regulation of ocean carbonate chemistry on time scales >1000-100 000 years. On glacial-interglacial scales, coccolithophore productivity could have affected deep-water saturation by buffering deep-sea CO2 through increased carbonate dissolution episodes. Spectral and wavelet analyses are consistent with CARs primarily driven by glacial-interglacial variability and obliquity-controlled changes. Coccolith-based paleoceanographic reconstructions allow us to establish that during the last 450 ka the mid-latitudes of the NW Pacific are controlled by the dynamics of the El Nino Southern Oscillation perturbations and Boreal Monsoon system.

  • 113.
    Bordiga, Manuela
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Geovetenskapliga sektionen, Institutionen för geovetenskaper, Paleobiologi.
    Henderiks, Jorijntje
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Geovetenskapliga sektionen, Institutionen för geovetenskaper, Paleobiologi.
    Variations in calcareous nannofossil assemblages during the Eocene-Oligocene transition at mid-latitude: Walvis Ridge ODP Site 1263 (Atlantic Ocean).2014Konferensbidrag (Övrigt vetenskapligt)
  • 114.
    Bordiga, Manuela
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Geovetenskapliga sektionen, Institutionen för geovetenskaper, Paleobiologi.
    Henderiks, Jorijntje
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Geovetenskapliga sektionen, Institutionen för geovetenskaper, Paleobiologi.
    Tori, F.
    Univ Florence, Dipartimento Sci Terra, I-50121 Florence, Italy..
    Monechi, S.
    Univ Florence, Dipartimento Sci Terra, I-50121 Florence, Italy..
    Fenero, R.
    Univ Zaragoza, Dept Ciencias Tierra, E-50009 Zaragoza, Spain.;Univ Zaragoza, Inst Univ Invest Ciencias Ambientales Aragon, E-50009 Zaragoza, Spain..
    Legarda-Lisarri, A.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Geovetenskapliga sektionen, Institutionen för geovetenskaper, Paleobiologi. Univ Zaragoza, Dept Ciencias Tierra, E-50009 Zaragoza, Spain.;Univ Zaragoza, Inst Univ Invest Ciencias Ambientales Aragon, E-50009 Zaragoza, Spain..
    Thomas, E.
    Yale Univ, Dept Geol & Geophys, New Haven, CT 06520 USA.;Wesleyan Univ, Dept Earth & Environm Sci, Middletown, CT 06459 USA..
    Microfossil evidence for trophic changes during the Eocene-Oligocene transition in the South Atlantic (ODP Site 1263, Walvis Ridge)2015Ingår i: Climate of the Past, ISSN 1814-9324, E-ISSN 1814-9332, Vol. 11, nr 9, s. 1249-1270Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The biotic response of calcareous nannoplankton to environmental and climatic changes during the Eocene-Oligocene transition was investigated at a high resolution at Ocean Drilling Program (ODP) Site 1263 (Walvis Ridge, southeast Atlantic Ocean) and compared with a lower-resolution benthic foraminiferal record. During this time interval, global climate, which had been warm under high levels of atmospheric CO2 (pCO(2)) during the Eocene, transitioned into the cooler climate of the Oligocene, at overall lower pCO(2). At Site 1263, the absolute nannofossil abundance (coccoliths per gram of sediment; N g(-1)) and the mean coccolith size decreased distinctly after the E-O boundary (EOB; 33.89 Ma), mainly due to a sharp decline in abundance of large-sized Reticulofenestra and Dictyococcites, occurring within a time span of similar to 47 kyr. Carbonate dissolution did not vary much across the EOB; thus, the decrease in abundance and size of nannofossils may reflect an overall decrease in their export production, which could have led to variations in the food availability for benthic foraminifers. The benthic foraminiferal assemblage data are consistent with a global decline in abundance of rectilinear species with complex apertures in the latest Eocene (similar to 34.5 Ma), potentially reflecting changes in the food source, i.e., phytoplankton. This was followed by a transient increased abundance of species indicative of seasonal delivery of food to the sea floor (Epistominella spp.; similar to 33.9-33.4 Ma), with a short peak in overall food delivery at the EOB (buliminid taxa; similar to 33.8 Ma). Increased abundance of Nuttallides umbonifera (at similar to 33.3 Ma) indicates the presence of more corrosive bottom waters and possibly the combined arrival of less food at the sea floor after the second step of cooling (Step 2). The most important changes in the calcareous nannofossil and benthic communities occurred similar to 120 kyr after the EOB. There was no major change in nannofossil abundance or assemblage composition at Site 1263 after Step 2 although benthic foraminifera indicate more corrosive bottom waters during this time. During the onset of latest-Eocene-earliest-Oligocene climate change, marine phytoplankton thus showed high sensitivity to fast-changing conditions as well as to a possibly enhanced, pulsed nutrient supply and to the crossing of a climatic threshold (e.g., pCO(2) decline, high-latitude cooling and changes in ocean circulation).

  • 115.
    Bordiga, Manuela
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Geovetenskapliga sektionen, Institutionen för geovetenskaper, Paleobiologi.
    Henderiks, Jorijntje
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Geovetenskapliga sektionen, Institutionen för geovetenskaper, Paleobiologi.
    Tori, Flavia
    Monechi, Simonetta
    Fenero, Raquel
    Thomas, Ellen
    Eocene-Oligocene shifts in nannofossil assemblages at ODP Site 1263 (Walvis Ridge, Atlantic Ocean)2015Konferensbidrag (Övrigt vetenskapligt)
  • 116.
    Bordiga, Manuela
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Geovetenskapliga sektionen, Institutionen för geovetenskaper, Paleobiologi.
    Henderiks, Jorijntje
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Geovetenskapliga sektionen, Institutionen för geovetenskaper, Paleobiologi.
    Tori, Flavia
    Monechi, Simonetta
    Fenero, Raquel
    Thomas, Ellen
    The Eocene-Oligocene transition at ODP Site 1263, Atlantic Ocean: decreases in nannoplankton size and abundance and correlation with benthic foraminiferal assemblages2015Ingår i: Climate of the Past Discussions, ISSN 1814-9340, E-ISSN 1814-9359, Vol. 11, s. 1615-1664Artikel i tidskrift (Övrigt vetenskapligt)
  • 117.
    Bordiga, Manuela
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Geovetenskapliga sektionen, Institutionen för geovetenskaper, Paleobiologi.
    Sulas, Camilla
    Florence Univ, Dept Earth Sci, Via Pira 4, I-50121 Florence, Italy..
    Henderiks, Jorijntje
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Geovetenskapliga sektionen, Institutionen för geovetenskaper, Paleobiologi.
    Reticulofenestra daviesii: Biostratigraphy and paleogeographic distribution across the Eocene-Oligocene boundary2017Ingår i: Geobios, ISSN 0016-6995, E-ISSN 1777-5728, Vol. 50, nr 5-6, s. 349-358Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Improving the biostratigraphy across the Eocene-Oligocene is fundamental to better constrain the timing and causes of an important global climate change of the Cenozoic, the Eocene-Oligocene Transition (EOT; 34-33.5 Ma). Across the EOT, only few nannofossil bioevents are considered globally synchronous and reliable. One of these is the first common occurrence (Bc) of the species Reticulofenestra daviesii that has been proven to be useful for biostratigraphical correlations in the Southern Ocean, but the potential of R. daviesii as a biostratigraphical marker at mid- and low latitudes has not been explored yet in detail. We investigate three deep-sea drill sites located across a N-S transect at mid-low latitudes of the Atlantic Ocean spanning from 34.4 to 33 Ma, reviewing the temporal and geographical distribution together with the intraspecific variability of R. daviesii. Our data quantify the occurrence of R. daviesii in (sub)tropical regions of the Atlantic Ocean, although with lower abundances (similar to 4-12%) compared to Southern Ocean assemblages (40-95%). This suggests that R. daviesii was a cosmopolitan species capable to adapt to a wider range of sea surface temperatures and environmental conditions than previously thought. However, the temporal distributions of R. daviesii at the three studied sites are not comparable to the trends recorded in the Southern Ocean. Its Bc is clearly identifiable only at the equatorial site, occurring similar to 500,000 years before the age estimated in the Southern Ocean (33.705 Ma). Thus, we suggest caution when using the Bc of R. daviesii as a reliable biostratigraphical event at mid- and low latitudes. In addition, our biometrical data reveal that up to 38% of R. daviesii coccoliths is > 8-10 mu m in major axis size, thus bigger than the medium size range (5-8 mu m) originally described. Refining the size range of R. daviesii is important for estimating its cell volume versus surface area and coccolith carbonate mass. (C) 2017 Elsevier Masson SAS. All rights reserved.

  • 118.
    Bornsäter Mellbin, Barbro
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Geovetenskapliga sektionen, Institutionen för geovetenskaper, Paleobiologi.
    Linguliform Brachiopods from the terminal Cambrain to lower Ordovician Tiñu section, Mexico2008Självständigt arbete på avancerad nivå (magisterexamen), 20 poäng / 30 hpStudentuppsats
    Abstract [sv]

    Tiñuformationen i Oaxaca, Mexiko är den enda fossilförande enheten från undre paleozoikum mellan den Laurentiska plattformen i nordvästra Mexiko och de Gondwanska lagerföljderna i Sydamerika. Det har nyligen visats att Tiñusektionen är en koncentrerad passiv kantlagerföljd med Gondwanakaraktär. Formationen delas upp i två delar; Yudachica från översta kambrium, som vilar okonformt på mellanproterozoisk grund, och Río Salinas från undre ordovicium (tremadoc). Formationen har tidigare studerats med avseende på dess avsättningsmiljöer och det fossila innehållet av trilobiter och konodonter vilka båda ger utmärkt biostratigrafisk kontroll över formationen.

    Ungefär 1000 exemplar av Linguliforma brachiopoder från tolv kalkstenslager från Tiñuformationen har studerats. Detaljerade undersökningar om taxonomi och stratigrafisk distribution av taxa har utförts. Faunan omfattar nio acrotretida taxa och en ny siphonotretid art och ett fåtal lingulida fragment. De acrotretida och det siphonotretida taxa har beskrivits grundligt och klassificerats till släkte.

  • 119.
    Bornsäter Mellbin, Barbro
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Geovetenskapliga sektionen, Institutionen för geovetenskaper. Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Geovetenskapliga sektionen, Institutionen för geovetenskaper, Paleobiologi.
    Streng, Michael
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Geovetenskapliga sektionen, Institutionen för geovetenskaper. Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Geovetenskapliga sektionen, Institutionen för geovetenskaper, Paleobiologi.
    Linguliform brachiopods from the terminal Cambrian to lower Ordovician Tiñu section, Mexico2007Ingår i: 51st Palaeontological Association Annual Meeting: Programme with Abstracts, 2007, s. 64-Konferensbidrag (Övrigt vetenskapligt)
    Abstract [en]
    The Tiñu Formation of Oaxaca State (Mexico) is the only fossiliferous lower Palaeozoic unit between the Laurentian platform in northwest Mexico and Gondwanan successions in Andean South America. It has recently been shown that the Tiñu section is a condensed passive margin succession with Gondwanan character. The formation is divided into two members, i.e., the uppermost Cambrian Yudachica Member, which rests nonconformably on middle Proterozoic basement, and the Lower Ordovician (Tremadoc) Río Salinas Member. The formation has been studied with respect to its depositional environments and its fossil content of trilobites and conodonts, which both provide excellent biostratigraphical control for the formation. Linguliform brachiopods of twelve limestone horizons of the Tiñu Formation have been studied. The fauna comprises about five acrotretid taxa, a new siphonotretid species and a few linguloid fragments. Detailed investigations on taxonomy and stratigraphic distribution of the taxa are currently in progress. An assessment of the changes in brachiopod associations across the Cambrian-Ordovician boundary and in relation to the described environmental changes occurring throughout the formation is one of the main points of the investigation.
  • 120. Bosak, S.
    et al.
    Ljubesic, Z.
    Supraha, Luka
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Geovetenskapliga sektionen, Institutionen för geovetenskaper, Paleobiologi.
    Neeley, A.
    Durkin, C. A.
    Estapa, M.
    Omand, M.
    Carlson, K.
    Cetinic, I.
    PHYTOPLANKTON SPECIES COMPOSITION CONTRIBUTING TO CARBON EXPORT - SEA TO SPACE PARTICLE INVESTIGATION2017Ingår i: Phycologia, ISSN 0031-8884, E-ISSN 2330-2968, Vol. 56, nr 4, s. 23-24Artikel i tidskrift (Övrigt vetenskapligt)
  • 121. Bosak, Sunčica
    et al.
    Šupraha, Luka
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Geovetenskapliga sektionen, Institutionen för geovetenskaper, Paleobiologi.
    Nanjappa, Deepak
    Kooistra, Wiebe H.C.F.
    Sarno, Diana
    Morphology and phylogeny of four species from the genus Bacteriastrum (Bacillariophyta)2015Ingår i: Phycologia, Vol. 54, nr 2, s. 130-148Artikel i tidskrift (Refereegranskat)
  • 122. Botting, Joseph P.
    et al.
    Cardenas, Paco
    Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Farmaceutiska fakulteten, Institutionen för läkemedelskemi, Avdelningen för farmakognosi. Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för organismbiologi, Systematisk biologi.
    Peel, John S.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Geovetenskapliga sektionen, Institutionen för geovetenskaper, Paleobiologi.
    A Crown-Group Demosponge from the Early Cambrian Sirius Passet Biota, North Greenland2015Ingår i: Palaeontology, ISSN 0031-0239, E-ISSN 1475-4983, Vol. 58, nr 1, s. 35-43Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Calibration of the divergence times of sponge lineages and understanding of their phylogenetic history are hampered by the difficulty in recognizing crown versus stem groups in the fossil record. A new specimen from the lower Cambrian (Series 2, Stage 3; approximately 515Ma) Sirius Passet Biota of North Greenland has yielded a diagnostic spicule assemblage of the extant demosponge lineages Haploscleromorpha and/or Heteroscleromorpha. The specimen has disarticulated approximately in situ, but represents an individual sponge that possessed monaxon spicules combined with a range of slightly smaller sigma, toxa and unique spiral morphologies. The combination of spicule forms, together with their relatively large size, suggests that the sponge represents the stem lineage of Haploscleromorpha+Heteroscleromorpha. This is the first crown-group demosponge described from the early Cambrian and provides the most reliable calibration point currently available for phylogenetic studies.

  • 123.
    Botting, Joseph P.
    et al.
    Nanjing Inst Geol & Palaeontol, 39 East Beijing Rd, Nanjing 210008, Jiangsu, Peoples R China.;Natl Museum Wales, Dept Geol, Cathays Pk, Cardiff CF10 3LP, S Glam, Wales..
    Peel, John S.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Geovetenskapliga sektionen, Institutionen för geovetenskaper, Paleobiologi.
    Early Cambrian Sponges Of The Sirius Passet Biota, North Greenland2016Ingår i: PAPERS IN PALAEONTOLOGY, ISSN 2056-2799, Vol. 2, nr 4, s. 463-487Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The Sirius Passet Biota of the Buen Formation in North Greenland is one of the key Burgess Shale-type faunas, as it represents the only diverse early Cambrian (Stage 2, Series 3) biota from Laurentia. The sponges are one of the major components of the fauna, although they appear to be much less abundant than arthropods, based on the available collections. At least 13 species are described here, including the new taxa Hamptonia limatula sp. nov., Lenica perversa sp. nov., Saetaspongia procera sp. nov., Constellatispongia canismajorii gen. et sp. nov. and Crassicoactum cucumis gen. et sp. nov. An additional new species, Ratcliffespongia freuchenensis sp. nov., is described from the upper part of the Buen Formation. The assemblage is dominated by a major lineage of protomonaxonids, together with rarer reticulosans and demosponges. Some taxa, such as the anthaspidellid lithistid Fieldospongia bellilineata, were previously known only from Laurentian faunas; others, such as Saetospongia densa, Solactiniella cf. plumata and Lenica unica, were previously recognized from South China and/or Siberia. The described assemblage confirms the cosmopolitan distribution of Cambrian sponges generally, and suggests that the differences between Laurentian and Chinese assemblages are due more to a taxonomic overturn during Cambrian Series 2, Stage 4, than to the geographical separation. Furthermore, crown-group demosponges appear to have occupied shallow-water (perhaps dominantly platform) environments at this time, and may have been much more diversified and widespread than is currently recognized during the early Cambrian.

  • 124. Bourdelle, C.
    et al.
    Andersson Sundén, Erik
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi, Tillämpad kärnfysik.
    Binda, F.
    Cecconello, Marco
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi, Tillämpad kärnfysik.
    Conroy, Sean
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi, Tillämpad kärnfysik.
    Dzysiuk, N.
    Ericsson, G.
    Eriksson, Jacob
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi, Tillämpad kärnfysik.
    Hellesen, C.
    Hjalmarsson, Anders
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi, Tillämpad kärnfysik.
    Possnert, Göran
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi, Högenergifysik. Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Geovetenskapliga sektionen, Institutionen för geovetenskaper, Paleobiologi. Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi, Tillämpad kärnfysik.
    Sjöstrand, Henrik
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi, Tillämpad kärnfysik.
    Skiba, Mateusz
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi, Tillämpad kärnfysik.
    Weiszflog, Matthias
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi, Tillämpad kärnfysik.
    Zychor, I.
    Fast H isotope and impurity mixing in ion-temperature-gradient turbulence2018Ingår i: Nuclear Fusion, ISSN 0029-5515, E-ISSN 1741-4326, Vol. 58, nr 7, artikel-id 076028Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    In ion-temperature-gradient (ITG) driven turbulence, the resonance condition leads to ion particle turbulent transport coefficients significantly larger than electron particle turbulent transport coefficients. This is shown in nonlinear gyrokinetic simulations and explained by an analytical quasilinear model. It is then illustrated by JETTO-QuaLiKiz integrated modelling. Large ion particle transport coefficients implies that the ion density profiles are uncorrelated to the corresponding ion source, allowing peaked isotope density profiles even in the absence of core source. This also implies no strong core accumulation of He ash. Furthermore, the relaxation time of the individual ion profiles in a multi-species plasma can be significantly faster than the total density profile relaxation time which is constrained by the electrons. This leads to fast isotope mixing and fast impurity transport in FM regimes. In trapped-electron- mode (TEM) turbulence, in presence of electron heating about twice the ion heating, the situation is the inverse: ion particle turbulent transport coefficients are smaller than their electron counterpart.

  • 125.
    Bremer, Oskar
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för organismbiologi, Evolution och utvecklingsbiologi.
    Kear, Benjamin
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Geovetenskapliga sektionen, Institutionen för geovetenskaper, Paleobiologi.
    Reassessment of the ‘last’ goniopholidid: denazinosuchus kirtlandicus from the late cretaceous of New Mexico2013Ingår i: Program and Abstract Book, 2013, s. 93-94Konferensbidrag (Övrigt vetenskapligt)
  • 126.
    Bremer, Oskar
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Geovetenskapliga sektionen, Institutionen för geovetenskaper, Paleobiologi.
    Kear, Benjamin P.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Geovetenskapliga sektionen, Institutionen för geovetenskaper, Paleobiologi.
    CT-scan of Parasaurolophus tubicen from the Sternberg Collection (Uppsala University)2011Ingår i: The 2nd Wiman Meeting. Carl Wiman's Legacy: 100 Years of Swedish Palaeontology / [ed] Benjamin P. Kear and Michael Streng, 2011, s. 4-Konferensbidrag (Övrigt vetenskapligt)
    Abstract [en]

    In 1922, Carl Wiman, head of the then Palaeontological Institute at Uppsala University, received a series of crates containing dinosaur remains from the Upper Cretaceous (upper Campanian–Maastrichtian) Kirtland Formation of New Mexico, U.S.A. The specimens had been collected in 1921 by the famous American fossil hunter, Charles H. Sternberg, during a commissioned 5 month field expedition to the in the San Juan Basin. Arguably, one of the most significant specimens recovered was the partial skull of the spectacular crested hadrosaur Parasaurolophus tubicen. The holotype (PMU 24925) comprises the massive crest and neurocranium, together with parts of the pareital, frontal, prefrontals, postorbitals, squamosals and exoccipitals. The right quadrate is also preserved in articulation with the quadratojugal and pterygoid; the right jugal, maxilla, pterygoid, ectopterygoid and the anterior section of the lacrimal make up the facial region of the skull. Wiman was the first to propose that the crest of Parasaurolophus functioned as a vocalization structure. This study aims to investigate the functional morphology of the crest in this hadrosaur, in conjunction with endocranial anatomy, using CT-scanning and 3D modelling of the intracranial chambers. Comparisons with other specimens of Parasaurolophus will permit reconstruction of sensory capabilities in this 'classic' dinosaur taxon.

  • 127. Brock, Glenn A.
    et al.
    Holmer, Lars E
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Geovetenskapliga sektionen, Institutionen för geovetenskaper, Paleobiologi.
    Early Ordovician brachiopods from the Emanuel Formation, Canning Basin, Western Australia2004Ingår i: Memoirs of the Association of Australasian Palaeontologists, ISSN 0810-8889, nr 30, s. 113-132Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The lingulate brachiopods from the type section of the Emanuel Fonnation, Canning Basin, Western Australia are described. The fauna consists on new obolid taxa, Libecoviella divaricata n. sp., Wahwahlingula? emanuelensis n. sp., and Zhanatellidae n. gen? A, and two acrotretoids, Semitreta lauriei n. sp., and Ottenbyella shidertensis (Popov & Holmer, 1994). Contemporaneous trilobite and conodont faunas indicate a late Lancefieldian (La3) to mid Bendigonian (Be2) (=earliest Arenigian) age for the Emanuel Fonnation. The lingulate fauna is largely endemic at the species level, with minor faunal links to Kazakhstan and Bohemia.

  • 128.
    Brocks, J. J.
    et al.
    Australian Natl Univ, Res Sch Earth Sci, Canberra, ACT, Australia..
    Jarrett, A. J. M.
    Australian Natl Univ, Res Sch Earth Sci, Canberra, ACT, Australia.;Geosci Australia, GPO BOX 378, Canberra, ACT 2601, Australia..
    Sirantoine, E.
    Australian Natl Univ, Res Sch Earth Sci, Canberra, ACT, Australia.;Ecole Normale Super Lyon, Dept Sci Terre, 46 Allee Italie, F-69007 Lyon, France..
    Kenig, F.
    Univ Illinois, Dept Earth & Environm Sci, Chicago, IL USA..
    Moczydlowska, Malgorzata
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Geovetenskapliga sektionen, Institutionen för geovetenskaper, Paleobiologi.
    Porter, S.
    Univ Calif Santa Barbara, Dept Earth Sci, Santa Barbara, CA 93106 USA..
    Hope, J.
    Australian Natl Univ, Res Sch Earth Sci, Canberra, ACT, Australia..
    Early sponges and toxic protists: possible sources of cryostane, an age diagnostic biomarker antedating Sturtian Snowball Earth2016Ingår i: Geobiology, ISSN 1472-4677, E-ISSN 1472-4669, Vol. 14, nr 2, s. 129-149Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The period 800-717million years (Ma) ago, in the lead-up to the Sturtian Snowball glaciation, saw an increase in the diversity of eukaryotic microfossils. To afford an independent and complementary view of this evolutionary period, this study presents the distribution of eukaryotic biomarkers from three pre-Sturtian successions across the supercontinent Rodinia: the ca. 780Ma Kanpa Formation of the Western Australian Officer Basin, the ca. 800-740Ma Visingso Group of Sweden, and the 740Ma Chuar Group in Arizona, USA. The distribution of eukaryotic steranes is remarkably similar in the three successions but distinct from all other known younger and older sterane assemblages. Cholestane was the only conventional structure, while indigenous steranes alkylated in position C-24, such as ergostane, stigmastane, dinosterane and isopropylcholestane, and n-propylcholestane, were not observed. This sterane distribution appears to be age diagnostic for the pre-Sturtian Neoproterozoic. It attests to the distinct evolutionary state of pre-Snowball eukaryotes, pointing to a taxonomic disparity that was still lower than in the Ediacaran (635-541Ma). All three basins also show the presence of a new C-28 sterane that was tentatively identified as 26-methylcholestane, here named cryostane. The only known extant organisms that can methylate sterols in the 26-position are demosponges. This assignment is plausible as molecular clocks place the appearance of the earliest animals into the pre-Sturtian Neoproterozoic. The unusual 26-methylsterol may have protected sponges, but also other eukaryotes, against their own membranolytic toxins. Some protists release lytic toxins to deter predators and kill eukaryotic prey. As conventional membrane sterols can be the site of attack for these toxins, sterols with unusual side-chain modification protect the cell. This interpretation of cryostane supports fossil evidence of predation in the Chuar Group and promotes hypotheses about the proliferation of eukaryophagy in the lead-up to the Cryogenian.

  • 129. Brosse, Morgane
    et al.
    Bucher, Hugo
    Bagherpour, Borhan
    Baud, Aymon
    Frisk, Åsa M.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Geovetenskapliga sektionen, Institutionen för geovetenskaper, Paleobiologi.
    Guodun, Kuang
    Goudemand, Nicolas
    Conodonts from the Early Triassic Microbialite of Guangxi (South China): Implications for the Definition of the Base of the Triassic System2015Ingår i: Palaeontology, ISSN 0031-0239, E-ISSN 1475-4983, Vol. 58, nr 3, s. 563-584Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    We describe a new Early Triassic (Griesbachian) succession of conodont faunas from a high-resolution sampling of the basal Early Triassic microbial limestone and the base of the overlying unit at the Wuzhuan section (Nanpanjiang Basin, Guangxi, South China). The microbial limestone records the earliest phase of the Early Triassic biotic recovery after the end-Permian mass extinction. For the first time, rich conodont faunas are reported from within the microbialite. The faunas from Wuzhuan are largely dominated by anchignathodontids, including several Isarcicella species, which were previously documented only from strata above the microbialite. A total of 14 conodont species assigned to three genera is recorded from the Wuzhuan section. Starting from the base of the microbialite upwards, several species are sequentially added to the conodont assemblage. The alpha diversity peaks at the top of the microbialite. The conodont record in the considered microbialite interval at Wuzhuan is presumably unaffected by local ecological changes. It therefore more likely represents an evolutionary rather than an ecological pattern. We compare the Wuzhuan's conodont record with a well-supported phylogenetic model and suggest that the sequence of first occurrences at Wuzhuan is the closest to the true' sequence of evolutionary events that took place during this Griesbachian radiation of anchignathodontids. Based on comparisons with the GSSP section at Meishan, we suggest further that the first occurrence of Hindeodus parvus in Meishan does not correspond to its first appearance datum.

  • 130.
    Brosse, Morgane
    et al.
    Univ Zurich, Palaontol Inst & Museum, Karl Schmid Str 4, CH-8006 Zurich, Switzerland.
    Bucher, Hugo
    Univ Zurich, Palaontol Inst & Museum, Karl Schmid Str 4, CH-8006 Zurich, Switzerland.
    Baud, Aymon
    BGC, Parc Rouvraie 28, CH-1018 Lausanne, Switzerland.
    Frisk, Åsa
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Geovetenskapliga sektionen, Institutionen för geovetenskaper, Paleobiologi.
    Goudemand, Nicolas
    Univ Claude Bernard Lyon 1, Univ Lyon, Inst Genom Fonct Lyon, ENS Lyon,CNRS,UMR 5242, 46 Allee Italie, F-69364 Lyon 07, France.
    Hagdorn, Hans
    Muschelkalkmuseum, Schlossstr 11, D-74653 Ingelfingen, Germany.
    Nützel, Alexander
    LMU, Dept Earth & Environm Sci, SNSB Bayer Staatssammlung Palaontol & Geol, GeoBio Ctr,Palaeontol & Geobiol, Richard Wagner Str 10, D-80333 Munich, Germany.
    Ware, David
    Leibniz Inst Evolut & Biodiversitatsforsch, Museum Nat Kunde, Invalidenstr 43, D-10115 Berlin, Germany.
    Hautmann, Michael
    Univ Zurich, Palaontol Inst & Museum, Karl Schmid Str 4, CH-8006 Zurich, Switzerland.
    New data from Oman indicate benthic high biomass productivity coupled with low taxonomic diversity in the aftermath of the Permian-Triassic Boundary mass extinction2019Ingår i: Lethaia: an international journal of palaeontology and stratigraphy, ISSN 0024-1164, E-ISSN 1502-3931, Vol. 52, nr 2, s. 165-187Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    A new Early Triassic marine fauna is described from an exotic block (olistolith) from the Ad Daffah conglomerate in eastern Oman (Batain), which provides new insights into the ecology and diversity during the early aftermath of the Permian-Triassic Boundary mass extinction. Based on conodont quantitative biochronology, we assign a middle Griesbachian age to the upper part of this boulder. It was derived from an offshore seamount and yielded both nektonic and benthic faunas, including conodonts, ammonoids, gastropods and crinoid ossicles in mass abundance. This demonstrates that despite the stratigraphically near extinction at the Permian-Triassic Boundary, Crinoidea produced enough biomass to form crinoidal limestone as early as middle Griesbachian time. Baudicrinus, previously placed in Dadocrinidae, is now placed in Holocrinidae; therefore, Dadocrinidae are absent in the Early Triassic, and Holocrinidae remains the most basal crown-group articulates, originating during the middle Griesbachian in the Tethyan Realm. Abundant gastropods assigned to Naticopsis reached a shell size larger than 20 mm and provide another example against any generalized Lilliput effect during the Griesbachian. Whereas the benthic biomass was as high as to allow the resumption of small carbonate factories, the taxonomic diversity of the benthos remained low compared to post-Early Triassic times. This slow benthic taxonomic recovery is here attributed to low competition within impoverished post-extinction faunas.

  • 131. Brown, Caleb Marshall
    et al.
    VanBuren, Collin S.
    Larson, Derek W.
    Brink, Kirstin S.
    Campione, Nicolas E.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Geovetenskapliga sektionen, Institutionen för geovetenskaper, Paleobiologi. Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för organismbiologi, Evolution och utvecklingsbiologi.
    Vavrek, Matthew J.
    Evans, David C.
    Tooth counts through growth in diapsid reptiles: implications for interpreting individual and size-related variation in the fossil record2015Ingår i: Journal of Anatomy, ISSN 0021-8782, E-ISSN 1469-7580, Vol. 226, nr 4, s. 322-333Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Tooth counts are commonly recorded in fossil diapsid reptiles and have been used for taxonomic and phylogenetic purposes under the assumption that differences in the number of teeth are largely explained by interspecific variation. Although phylogeny is almost certainly one of the greatest factors influencing tooth count, the relative role of intraspecific variation is difficult, and often impossible, to test in the fossil record given the sample sizes available to palaeontologists and, as such, is best investigated using extant models. Intraspecific variation (largely manifested as size-related or ontogenetic variation) in tooth counts has been examined in extant squamates (lizards and snakes) but is poorly understood in archosaurs (crocodylians and dinosaurs). Here, we document tooth count variation in two species of extant crocodylians (Alligator mississippiensis and Crocodylus porosus) as well as a large varanid lizard (Varanus komodoensis). We test the hypothesis that variation in tooth count is driven primarily by growth and thus predict significant correlations between tooth count and size, as well as differences in the frequency of deviation from the modal tooth count in the premaxilla, maxilla, and dentary. In addition to tooth counts, we also document tooth allometry in each species and compare these results with tooth count change through growth. Results reveal no correlation of tooth count with size in any element of any species examined here, with the exception of the premaxilla of C.porosus, which shows the loss of one tooth position. Based on the taxa examined here, we reject the hypothesis, as it is evident that variation in tooth count is not always significantly correlated with growth. However, growth trajectories of smaller reptilian taxa show increases in tooth counts and, although current samples are small, suggest potential correlates between tooth count trajectories and adult size. Nevertheless, interspecific variation in growth patterns underscores the importance of considering and understanding growth when constructing taxonomic and phylogenetic characters, in particular for fossil taxa where ontogenetic patterns are difficult to reconstruct.

  • 132.
    Budd, G. E.
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Geovetenskapliga sektionen, Institutionen för geovetenskaper. Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Geovetenskapliga sektionen, Institutionen för geovetenskaper, Paleobiologi. Paleobiologi.
    Högström, Anette E. S.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Geovetenskapliga sektionen, Institutionen för geovetenskaper. Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Geovetenskapliga sektionen, Institutionen för geovetenskaper, Paleobiologi. Paleobiologi.
    Gogin, I.
    A myriapod-like arthropod from the Upper Cambrian of East Siberia2001Ingår i: Paläontologisches Zeitschrift, Vol. 75, nr 1, s. 37-41Artikel i tidskrift (Refereegranskat)
  • 133.
    Budd, G.E.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Geovetenskapliga sektionen, Institutionen för geovetenskaper. Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Geovetenskapliga sektionen, Institutionen för geovetenskaper, Paleobiologi. PALAEOBIOLOGY.
    Animal Phyla2003Ingår i: Keywords and concepts in Evolutionary Developmental Biology, 2003, s. 1-9Kapitel i bok, del av antologi (Övrigt vetenskapligt)
  • 134.
    Budd, G.E.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Geovetenskapliga sektionen, Institutionen för geovetenskaper. Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Geovetenskapliga sektionen, Institutionen för geovetenskaper, Paleobiologi. PALAEOBIOLOGY.
    Arthropods as Ecdysozoans: the fossil evidence2003Kapitel i bok, del av antologi (Refereegranskat)
  • 135.
    Budd, G.E.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Geovetenskapliga sektionen, Institutionen för geovetenskaper. Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Geovetenskapliga sektionen, Institutionen för geovetenskaper, Paleobiologi. PALAEOBIOLOGY.
    Lower Metazoans2003Ingår i: Grzimek´s Animal Life Encyclopedia, 2003, s. 3-6Kapitel i bok, del av antologi (Övrigt vetenskapligt)
  • 136.
    Budd, GE
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Geovetenskapliga sektionen, Institutionen för geovetenskaper. Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Geovetenskapliga sektionen, Institutionen för geovetenskaper, Paleobiologi.
    Palaeontology - Lost children of the Cambrian2004Ingår i: Nature, Vol. 427, nr 6971, s. 205-207Artikel i tidskrift (Refereegranskat)
  • 137.
    Budd, G.E.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Geovetenskapliga sektionen, Institutionen för geovetenskaper. Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Geovetenskapliga sektionen, Institutionen för geovetenskaper, Paleobiologi. PALAEOBIOLOGY.
    The Cambrian fossil record and the origin of the phyla2003Ingår i: Integrative and comparative biology, Vol. 43, nr 1Artikel i tidskrift (Refereegranskat)
  • 138.
    Budd, G.E. and Jensen, S.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Geovetenskapliga sektionen, Institutionen för geovetenskaper. Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Geovetenskapliga sektionen, Institutionen för geovetenskaper, Paleobiologi. PALAEOBIOLOGY.
    The Limitations of the Fossil Record and the Dating of the Origin of the Bilateria2003Ingår i: Systematics Association Special Volumes, Vol. 66Artikel i tidskrift (Refereegranskat)
  • 139.
    Budd, Graham E.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Geovetenskapliga sektionen, Institutionen för geovetenskaper, Paleobiologi.
    Animal Evolution: Trilobites on Speed2013Ingår i: Current Biology, ISSN 0960-9822, E-ISSN 1879-0445, Vol. 23, nr 19, s. R878-R880Artikel i tidskrift (Övrigt vetenskapligt)
  • 140.
    Budd, Graham E.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Geovetenskapliga sektionen, Institutionen för geovetenskaper, Paleobiologi.
    At the Origin of Animals: The Revolutionary Cambrian Fossil Record2013Ingår i: Current Genomics, ISSN 1389-2029, E-ISSN 1875-5488, Vol. 14, nr 6, s. 344-354Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The certain fossil record of animals begins around 540 million years ago, close to the base of the Cambrian Period. A series of extraordinary discoveries starting over 100 years ago with Walcott's discovery of the Burgess Shale has accelerated in the last thirty years or so with the description of exceptionally-preserved Cambrian fossils from around the world. Such deposits of "Burgess Shale Type" have been recently complemented by other types of exceptional preservation. Together with a remarkable growth in knowledge about the environments that these early animals lived in, these discoveries have long exerted a fascination and strong influence on views on the origins of animals, and indeed, the nature of evolution itself. Attention is now shifting to the period of time just before animals become common, at the base of the Cambrian and in the preceding Ediacaran Period. Remarkable though the Burgess Shale deposits have been, a substantial gap still exists in our knowledge of the earliest animals. Nevertheless, the fossils from this most remarkable period of evolutionary history continue to exert a strong influence on many aspects of animal evolution, not least recent theories about developmental evolution.

  • 141.
    Budd, Graham E.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Geovetenskapliga sektionen, Institutionen för geovetenskaper, Paleobiologi.
    Campanamuta mantonae gen. et. sp. nov., an exceptionally preserved arthropod from the Sirius Passet Fauna (Buen Formation, lower Cambrian, North Greenland)2011Ingår i: Journal of Systematic Palaeontology, ISSN 1477-2019, E-ISSN 1478-0941, Vol. 9, nr 2, s. 217-260Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Specimens of the paneuarthropod Campanamuta mantonae gen. et sp. nov. are described from the lower Cambrian Sirius Passet Fauna of North Greenland. It is one of the most common taxa in the present collections from the Sirius Passet Fauna, being represented by some 1700 specimens (19%) of an estimated total of perhaps 8500 fossils of the collections studied. Unusually, much internal anatomy of Campanamuta has been preserved. However, interpretation of the preserved structures has been hampered by their variable appearance in different specimens and because of the degree of compression that has occurred. This paper describes the external and internal morphology of Campanamuta, and discusses the problems involved in its reconstruction. A model for the internal architecture of the animal is proposed, which recognizes the preservation of apodemes, musculature and the gut, providing the most complete picture of the internal anatomy of any Cambrian arthropod. This morphology complements that preserved in the Chengjiang and Burgess Shale taxa and adds a new source of data for the reconstruction of basal euarthropod phylogeny.

  • 142.
    Budd, Graham E.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Geovetenskapliga sektionen, Institutionen för geovetenskaper, Paleobiologi.
    Head structure in upper stem-group euarthropods2008Ingår i: Palaeontology, ISSN 0031-0239, E-ISSN 1475-4983, Vol. 51, nr 3, s. 561-573Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Continuing debate over the evolution and morphology of the arthropod head has led to considerable interest in the relevance of the evidence from the fossil record. However, dispute over homology and even presence of appendages and sclerites in Cambrian arthropods has resulted in widely differing views of their significance. The head structures of several important taxa, Fuxianhuia, Canadaspis, Odaraia, Chengjiangocaris and Branchiocaris are redescribed, revealing the essential similarity between them. In particular, all possessed an anterior sclerite, probably followed by a large posterior, ventral sclerite that is likely to be homologous to the hypostome of trilobites. The presence of a similar feature in Sanctacaris is also possible, but less well-supported. An anterior sclerite, usually bearing eyes, as in Fuxianhuia, appears to be a widespread feature of basal arthropods. Whether or not this sclerite represents an original articulating protocerebral segment on its own is, however, open to debate.

  • 143.
    Budd, Graham E.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Geovetenskapliga sektionen, Institutionen för geovetenskaper, Paleobiologi.
    International Congress on Invertebrate Morphology – plenary papers2010Samlingsverk (redaktörskap) (Övrigt vetenskapligt)
  • 144.
    Budd, Graham E
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Geovetenskapliga sektionen, Institutionen för geovetenskaper. Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Geovetenskapliga sektionen, Institutionen för geovetenskaper, Paleobiologi.
    On the origin and evolution of major morphologicla characters2006Ingår i: Biological Reviews, Vol. 81, s. 609-628Artikel i tidskrift (Refereegranskat)
  • 145.
    Budd, Graham E.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Geovetenskapliga sektionen, Institutionen för geovetenskaper, Paleobiologi.
    Palaeontological Approaches to the Arthropod Head ProblemKonferensbidrag (Övrigt vetenskapligt)
    Abstract [en]

    The arthropod head problem remains a daunting problem, and stillremains some distance away from solution: several distinct palaeontologicalcontributions have been made in the last few years alone. Suchwork needs to be integrated into molecular and developmentalapproaches to make the most effective assault on the problem. The statusof the labrum, its cross-group homology, and its appendiculate ornonappendiculate nature, remains particularly controversial. Nevertheless,some progress has been made by the erection of various stemgroupsto arthropod taxa, and these allow the partial tracing of the evolutionof the arthropod head. Recent work suggests that the upper stemgroupeuarthropods are all characterized by similar head structures, theorigins of which in turn may be traced back even deeper into the anomalocarididsand their relatives. Nevertheless, several potentially key taxa,such as Sanctacaris, remain hard to understand, whilst others, notablySidneyia, are typically ignored in analyses of the problem. Such taxamay have bearings on the origin of the upper euarthropod stem groupand chelicerate stem group, respectively. Despite the apparent argumentsraging about the fossil arthropod systematics, a distinct convergence ofopinion over many clades has taken place over the last few years: puttingthem together to form a consensus of palaeontological input intoresolving the arthropod head problem, however, remains some way off.

  • 146.
    Budd, Graham E.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Geovetenskapliga sektionen, Institutionen för geovetenskaper, Paleobiologi.
    Palaeontology: Cambrian nervous wrecks2012Ingår i: Nature, ISSN 0028-0836, E-ISSN 1476-4687, Vol. 490, nr 7419, s. 180-181Artikel i tidskrift (Övrigt vetenskapligt)
  • 147.
    Budd, Graham E.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Geovetenskapliga sektionen, Institutionen för geovetenskaper, Paleobiologi.
    The earliest fossil record of the animals and its significance2008Ingår i: Philosophical Transactions of the Royal Society of London. Biological Sciences, ISSN 0962-8436, E-ISSN 1471-2970, Vol. 363, nr 1496, s. 1425-1434Artikel, forskningsöversikt (Refereegranskat)
    Abstract [en]

    The fossil record of the earliest animals has been enlivened in recent years by a series of spectacular discoveries, including embryos, from the Ediacaran to the Cambrian, but many issues, not least of dating and interpretation, remain controversial. In particular, aspects of taphonomy of the earliest fossils require careful consideration before pronouncements about their affinities. Nevertheless, a reasonable case can now be made for the extension of the fossil record of at least basal animals (sponges and perhaps cnidarians) to a period of time significantly before the beginning of the Cambrian. The Cambrian explosion itself still seems to represent the arrival of the bilaterians, and many new fossils in recent years have added significant data on the origin of the three major bilaterian clades. Why animals appear so late in the fossil record is still unclear, but the recent trend to embrace rising oxygen levels as being the proximate cause remains unproven and may even involve a degree of circularity.

  • 148.
    Budd, Graham E.
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Geovetenskapliga sektionen, Institutionen för geovetenskaper, Paleobiologi.
    Daley, Allison C.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Geovetenskapliga sektionen, Institutionen för geovetenskaper, Paleobiologi.
    The lobes and lobopods of Opabinia regalis from the middle Cambrian Burgess Shale2012Ingår i: Lethaia: an international journal of palaeontology and stratigraphy, ISSN 0024-1164, E-ISSN 1502-3931, Vol. 45, nr 1, s. 83-95Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Despite many papers devoted to it, the morphology of the Burgess Shale animal Opabinia regalis continues to excite controversy. In particular, the trunk region remains incompletely understood, leading to several recent attempts to interpret the fossil in radically different ways. New material of Opabinia from the Royal Ontario Museum and the Smithsonian collection, together with the recent description of comparative material of the Burgess Shale anomalocaridid Hurdia, help clarify details of its morphology, in particular with regards to the lateral lobes and setal blades. A recent reconstruction of the trunk lobes is rejected, and further evidence for the presence of trunk limbs is presented. Despite disagreements over its morphology, the phylogenetic placement of Opabinia is now relatively uncontroversial, although various derived aspects of its morphology complicate placing it precisely.

  • 149.
    Budd, Graham E.
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Geovetenskapliga sektionen, Institutionen för geovetenskaper, Paleobiologi.
    Mann, Richard P.
    Univ Leeds, Sch Math, Dept Stat, Leeds LS2 9JT, W Yorkshire, England;Alan Turing Inst, London NW1 2DB, England.
    Modeling durophagous predation and mortality rates from the fossil record of gastropods2019Ingår i: Paleobiology, ISSN 0094-8373, E-ISSN 1938-5331, Vol. 45, nr 2, s. 246-264Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Gastropods often show signs of unsuccessful attacks by durophagous predators in the form of healed scars in their shells. As such, fossil gastropods can be taken as providing a record of predation through geological time. However, interpreting the number of such scars has proved to be problematic-Would a low number of scars mean a low rate of attack or a high rate of success, for example? Here we develop a model of population dynamics among individuals exposed to predation, including both lethal and nonlethal attacks. Using this model, we calculate the equilibrium distributions of ages and healed scars in the population and among fossilized specimens, based on the assumption that predation is independent of age or scar number. Based on these results, we formally show that the rates of attack and success cannot be disambiguated without further information about population structure. Nevertheless, by making the assumptions that the non-durophagous predatory death rate is both constant and low, we show that it is possible to use relatively small assemblages of gastropods to produce accurate estimates of both attack and success rates, if the overall death rate can be estimated. We consider likely violations of the assumptions in our model and what sort of information would be required to solve this problem in these more general cases. However, it is not easy to extract the relevant information from the fossil record: a variety of important biases are likely to intervene to obscure the data that gastropod assemblages may yield. Nonetheless, the model provides a theoretical framework for interpreting summary data, including for comparison between different assemblages.

  • 150.
    Budd, Graham E.
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Geovetenskapliga sektionen, Institutionen för geovetenskaper, Paleobiologi.
    Meidla, Tonu
    Univerity of Tartu.
    Willman, Sebastian
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Geovetenskapliga sektionen, Institutionen för geovetenskaper, Paleobiologi.
    Fossils & rocks: geotourism in the central Baltic2011Bok (Övrig (populärvetenskap, debatt, mm))
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