Results 311 to 320 of about 80,006 (331)
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Morphological Disparity in the Cambrian
Science, 1992An analysis of the range of morphology among arthropods demonstrates that disparity among living arthropods is similar to that in Cambrian arthropods. The range of morphological design resulting from the Cambrian "explosion" has been overestimated, reflecting a tendency to separate as "problematic" taxa that cannot be accommodated in the classification
Briggs, DEG, Fortey, RA, Wills, MA
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Science, 2018
New fossils and sites are helping make sense of the mysterious flowering of animal life half a billion years ago.
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New fossils and sites are helping make sense of the mysterious flowering of animal life half a billion years ago.
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Crustaceans and the "Cambrian Explosion"
Science, 2001We noted with interest the report by Siveter et al . ([1][1]) of new phosphatocopid specimens showing soft-part preservation from the Lower Cambrian Comley Limestones, but we question some of the interpretations both in the report and in the accompanying Perspective by Fortey ([2][2]). First,
Sören Jensen +2 more
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2016
Based on trace-fossil evidence, the Cambrian explosion emerges as one of the most dramatic events in the history of the biosphere. Ichnologic data are highly valuable as an independent line of evidence with respect to the body-fossil record and molecular clocks to explore the nature of this event and the associated evolutionary innovations. In contrast
M. Gabriela Mángano, Luis A. Buatois
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Based on trace-fossil evidence, the Cambrian explosion emerges as one of the most dramatic events in the history of the biosphere. Ichnologic data are highly valuable as an independent line of evidence with respect to the body-fossil record and molecular clocks to explore the nature of this event and the associated evolutionary innovations. In contrast
M. Gabriela Mángano, Luis A. Buatois
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, 1978 Forty selected radiometric ages are plotted to illustrate a time scale for the Cambrian System and strata immediately above and below. Uncertainty is unavoidable at present, not only because the boundaries of the system are the subject of international working group investigations which are not complete, but also because the radiometric age ...
S. J. Cribb, J. W. Cowie
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Palaeoworld, 2006
Abstract The Cambrian of Malaysia is best represented by the quartzose Machinchang Formation in Langkawi, Kedah, northwest Peninsular Malaysia. It is divisible into three members. The oldest Hulor Member (>1260 m thick) is a coarsening upward succession of rhythmically interlayered graded siltstone, mudstone and clayey sandstone deposited as a ...
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Abstract The Cambrian of Malaysia is best represented by the quartzose Machinchang Formation in Langkawi, Kedah, northwest Peninsular Malaysia. It is divisible into three members. The oldest Hulor Member (>1260 m thick) is a coarsening upward succession of rhythmically interlayered graded siltstone, mudstone and clayey sandstone deposited as a ...
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Journal of the Geological Society of Australia, 1963
Abstract The Cambrian System by definition must include the rocks (in the Caledonian geosyncline of Wales) to which this name was first applied. Its type sequence, however, does not define its boundaries. Evidence on the base of the Cambrian can be found in the Caledonian sedimentary areas of Scandinavia and in the adjoining Baltic region where the ...
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Abstract The Cambrian System by definition must include the rocks (in the Caledonian geosyncline of Wales) to which this name was first applied. Its type sequence, however, does not define its boundaries. Evidence on the base of the Cambrian can be found in the Caledonian sedimentary areas of Scandinavia and in the adjoining Baltic region where the ...
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Research-Technology Management, 2013
"The future is already here--it's just not very evenly distributed. " William Gibson As this issue of RTM arrives in your mailbox, IRI--our publisher--enters its 75th year. It does so at what John Seely Brown would call a Cambrian moment for innovation, an era of explosive change with the potential to forge profound changes in the way we work, learn ...
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"The future is already here--it's just not very evenly distributed. " William Gibson As this issue of RTM arrives in your mailbox, IRI--our publisher--enters its 75th year. It does so at what John Seely Brown would call a Cambrian moment for innovation, an era of explosive change with the potential to forge profound changes in the way we work, learn ...
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Pre-Cambrian and Cambrian relations in the upper Mississippi Valley
Geological Society of America Bulletin, 1935INTRODUCTION This paper presents the results of an investigation of two of the stratigraphic problems of the upper Mississippi Valley, pointed out by Trowbridge and Atwater1 in 1934. At that time a review of the stratigraphy of the upper Mississippi Valley was given, a number of problems that the authors believed to be as yet unsolved were outlined ...
G. I. Atwater, G. M. Clement
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Geological Society, London, Special Publications, 1964
Summary Fifteen selected radiometric ages are used to construct a time-scale for the Cambrian System. Maximum thicknesses are not considered to be useful in constructing a Cambrian time-scale. Ages of 495 m.y. and 570 m.y. are suggested for the top and base of the system, with ages of 540 m.y. and 515 m.y.
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Summary Fifteen selected radiometric ages are used to construct a time-scale for the Cambrian System. Maximum thicknesses are not considered to be useful in constructing a Cambrian time-scale. Ages of 495 m.y. and 570 m.y. are suggested for the top and base of the system, with ages of 540 m.y. and 515 m.y.
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