Search for dissertations about: "Cambrian"

Showing result 11 - 15 of 40 swedish dissertations containing the word Cambrian.

  2. 11. Decoding the fossil record of early lophophorates : Systematics and phylogeny of problematic Cambrian Lophotrochozoa

    Author : Aodhán D. Butler; Michael Streng; Lars E. Holmer; Russell Garwood; Maggie Cusack; Uppsala universitet; []
    Keywords : 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;

    Abstract : The evolutionary origins of animal phyla are intimately linked with the Cambrian explosion, a period of radical ecological and evolutionary innovation that begins approximately 540 Mya and continues for some 20 million years, during which most major animal groups appear. Lophotrochozoa, a major group of protostome animals that includes molluscs, annelids and brachiopods, represent a significant component of the oldest known fossil records of biomineralised animals, as disclosed by the enigmatic ‘small shelly fossil’ faunas of the early Cambrian. READ MORE

  4. 12. The Early Cambrian Fauna of North-East Greenland

    Author : Christian B. Skovsted; John S. Peel; Lars E. Holmer; Gerd Geyer; Uppsala universitet; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; Earth sciences; Early Cambrian; Dyeran; Botoman; Biostratigraphy; Palaeogeography; Small Shelly Fossils; Brachiopoda; Mollusca; Hyolitha; Trilobita; Geovetenskap; Earth sciences; Geovetenskap;

    Abstract : Small shelly fossils are common in sediments of Early Cambrian age and include the earliest common representatives of metazoan animals with mineralized hard parts. The group includes fossils of very different morphology, composition and ultrastructure. READ MORE

  5. 13. Cambro-Ordovician microorganisms: acritarchs and endoliths

    Author : Martin Stockfors; Malgorzata Vidal-Moczydlowska; John S. Peel; Kenneth John Dorning; Uppsala universitet; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; Earth sciences; Cambrian; Ordovician; acritarch; endolith; Kolguev Island; North Greenland; Stratigraphy; Geovetenskap; Earth sciences; Geovetenskap;

    Abstract : Organic-walled microfossils are abundant and taxonomically diverse in Cambrian-Ordovician strata; some are important for biostratigraphy and for the correlation of geological successions. New assemblages of Cambrian-Ordovician acritarchs from Kolguev Island, Arctic Russia and Middle Cambrian ichnofossils of endoliths from Peary Land, North Greenland are studied. READ MORE

  6. 14. The morphology and evolutionary significance of the anomalocaridids

    Author : Allison Daley; Graham E. Budd; Nigel C. Hughes; Uppsala universitet; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; anomalocaridids; Cambrian; Burgess Shale; exceptional preservation; palaeontology; Historical geology and palaeontology; Historisk geologi och paleontologi; Historical Geology and Paleontology; Historisk geologi och paleontologi;

    Abstract : Approximately 600 to 500 million years ago, a major evolutionary radiation called the “Cambrian Explosion” gave rise to nearly all of the major animal phyla known today. This radiation is recorded by various fossil lagerstätten, such as the Burgess Shale in Canada, where soft-bodied animals are preserved in exquisite detail. READ MORE

  7. 15. Neoproterozoic-Early Cambrian organic-walled microfossils : Ultrastructural and biogeochemical search for their affinities

    Author : Nina M. Talyzina; Uppsala universitet; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; Earth sciences; Geovetenskap; Earth sciences; Geovetenskap; Historical Geology and Paleontology; historisk geologi och paleontologi;

    Abstract : The Neoproterozoic-Cambrian transition is marked by conspicuous radiation of skeletal fauna comparable to modern invertebrates. Phylogenetic relationships of living organisms, based on their genetic and ultrastructural complexity, suggest that most prokaryotic and protistan organisms should have evolved by the time of origination of coelomate organisms. READ MORE