Sökning: "cambrian"

Visar resultat 1 - 5 av 41 avhandlingar innehållade ordet cambrian.

  1. 1. The Cambrian lophotrochozoans of the Transantarctic Mountains, Antarctica

    Författare :Lewis Bassett-Butt; Lars Holmer; Glenn Brock; Christian Skovsted; Jan Ove Ebbestad; Uppsala universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Brachiopoda; Dailyatia; Cambrian; Drumian; Middle Cambrian; Early Cambrian; Antarctica; tommotiid; camenellan; palaeobiology; small shelly fossils; Earth Science with specialization in Historical Geology and Palaeontology; Geovetenskap med inriktning mot historisk geologi och paleontologi;

    Sammanfattning : The origin of many lophotrochozoan groups can be traced to “small shelly fossil” (SSF) faunas of the Early Cambrian. Antarctica is a key region of study, due to the continent’s known close geographical proximity to well-studied Australian and Indian basins in in the Cambrian. LÄS MER

  3. 2. Exceptionally Preserved Cambrian Lophotrochozoa : Taxonomy, Systematics and Taphonomy of Chengjiang and Indian Springs Lophophorates

    Författare :Aodhán D. Butler; Michael Streng; Lars E. Holmer; Christian Skovsted; Uppsala universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; Brachiopoda; Chengjiang; Lagerstätte; Cambrian Explosion; palaeobiology; stem-group; entoproct; phoronid; tommotiid; exceptional preservation.; Earth Science with specialization in Historical Geology and Palaeontology; Geovetenskap med inriktning mot historisk geologi och paleontologi;

    Sammanfattning : The origin and evolution of Lophotrochozoa can be traced to the plethora of lower Cambrian scleritome taxa.  We aim to determine the character suites linking these stem-Lophotrochozoa to their extant crown relatives, in particular the small shelly tommotiids and the stem-group brachiopods. LÄS MER

  4. 3. The Evolutionary Significance of Cambrian Ecdysozoan Trace Fossils

    Författare :Giannis Kesidis; Graham Budd; Liam Herringshaw; Uppsala universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; Cambrian; trace fossil; Cruziana; Rusophycus; Treptichnus; Ecdysozoa;

    Sammanfattning : The origin of most of the animal phyla is tied to the Cambrian explosion, a rapid diversification event that took place from about 540 million years ago. This diversification is coupled with a great number of concurrent metazoan body plan innovations such as the development of the coelom, antagonistic muscles and a through-gut. LÄS MER

  5. 4. Palaeobiology and diversification of Proterozoic-Cambrian photosynthetic eukaryotes

    Författare :Heda Agić; Małgorzata Moczydłowska; Shuhai Xiao; Uppsala universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; microfossils; eukaryotes; Mesoproterozoic; Neoproterozoic; Cambrian; Ordovician; palaeobiology; biostratigraphy; phylogeny; China; Estonia; Siberian Platform; prasinophytes; microstructure; Raman spectroscopy; Earth Science with specialization in Historical Geology and Palaeontology; Geovetenskap med inriktning mot historisk geologi och paleontologi;

    Sammanfattning : One of the most important events in the history of life is the evolution of the complex, eukaryotic cell. The eukaryotes are complex organisms with membrane-bound intracellular structures, and they include a variety of both single-celled and multicellular organisms: plants, animals, fungi and various protists. LÄS MER

  7. 5. Early Cambrian Problematic Lophotrochozoans and Dilemmas of Scleritome Reconstructions

    Författare :Cecilia M Larsson; Lars E Holmer; Christian B Skovsted; Anette E S Högström; John S Peel; Glenn A Brock; Michael J Vendrasco; Uppsala universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; Problematica; scleritome; Trachyplax; tommotiid; Cambrian; South Australia; North Greenland; Earth Science with specialization in Historical Geology and Palaeontology; Geovetenskap med inriktning mot historisk geologi och paleontologi;

    Sammanfattning : The emergence and radiation of metazoan body plans around the Precambrian/Cambrian boundary, some 500-600 million years ago, seems to be concordant with the appearance and diversification of preservable hard parts. Several Precambrian soft-bodied, multicellular organisms most likely represent stem-group bilaterians, but their fossil record is rather sparse. LÄS MER