DOI: 10.1016/j.palaeo.2013.06.028
论文题名: Evolutionary patterns and palaeobiogeography of Pliensbachian and Toarcian (Early Jurassic) Radiolaria
作者: Goričan T. ; Carter E.S. ; Guex J. ; O'Dogherty L. ; De Wever P. ; Dumitrica P. ; Hori R.S. ; Matsuoka A. ; Whalen P.A.
刊名: Palaeogeography, Palaeoclimatology, Palaeoecology
ISSN: 0031-0182
出版年: 2013
卷: 386 起始页码: 620
结束页码: 636
语种: 英语
英文关键词: Extinction
; Lower Jurassic
; Palaeobiogeography
; Pliensbachian
; Radiation
; Radiolaria
; Toarcian
英文摘要: Recent studies on the global distribution of Pliensbachian and Toarcian polycystine radiolarians allowed us to examine faunal turnovers and the biogeography through this critical time interval around a major ecologic and biotic crisis. The analysis is based on the distribution of 167 species belonging to 69 genera. Significant variations in the ratio between the number of originating and extinct species have been recognized. During the early Early Pliensbachian FADs greatly exceeded LADs and the maximum diversity was reached in the late Early Pliensbachian. The trend then reversed with the number of LADs exceeding FADs throughout the Late Pliensbachian and Early Toarcian (extinction interval). Recovery started in the Middle and Late Toarcian, when the number of FADs again surpassed the number of LADs.Three differing evolutionary patterns are observed amongst radiolarian genera through the studied time interval. The largest group diversified rapidly in the Early Pliensbachian and experienced higher extinction rates in the Late Pliensbachian and Early Toarcian; a second group exhibited no major changes; and a third group of mainly spongy spumellarians was successful during the extinction interval. The overall trend of radiolarian diversity is in a fairly good agreement with that of other marine faunas (ammonites and also benthos), but shows an inverse correlation with diversity trends of phytoplankton.Correlation with concomitant environmental changes indicates that radiolarian radiation/extinction rates were not consistently linked with temperature fluctuations or sea-level changes. It is also evident that the diversity decrease started well before the Early Toarcian negative δ13C peak and the Oceanic Anoxic Event (OAE). The extinction interval corresponds well to the duration of a short-term anomaly in the strontium-isotope record, including the rapid decrease of 87Sr/86Sr values in the Late Pliensbachian as well as the rapid increase in the Early Toarcian. This coincidence supports the hypothesis that the predominance of extinctions over originations was caused by a series of climate and environmental changes related to intensified magmatic activity.Some distinct biogeographic differences have been observed. Generic differences are most strongly displayed by the presence or absence of a particular genus or by changes in abundance while species differences range from greater variability to having completely different species in separate palaeolatitudinal realms. Two groups of genera are distinguished: those that are common to abundant in the Tethys (low latitudes) and rare to absent in mid to high latitudes, and those common to abundant in mid to high latitudes and rare to absent in the Tethys. © 2013 Elsevier B.V. Citation statistics:
资源类型: 期刊论文
标识符: http://119.78.100.158/handle/2HF3EXSE/69663
Appears in Collections: 过去全球变化的重建
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作者单位: Paleontološki inštitut Ivana Rakovca, ZRC SAZU, Novi trg 2, SI-1000 Ljubljana, Slovenia; Department of Geology, Portland State University, Portland, United States; Institut de Géologie et Paléontologie, Université de Lausanne, CH-1015 Lausanne, Switzerland; Departamento de Ciencias de la Tierra, Facultad de Ciencias del Mar, Universidad de Cádiz, Campus Río S. Pedro, 11510 Puerto Real, Cádiz, Spain; Département Histoire de la Terre, Muséum National d'Histoire Naturelle, 43 rue Buffon, F-75005 Paris, France; Dennigkofenweg 33, CH-3073 Guemligen, Switzerland; Department of Earth Sciences, Faculty of Science, Niigata University, Niigata 950-2181, Japan; Department of Geology, Faculty of Science, Ehime University, Matsuyama 790-8577, Japan; Department of Geosciences, University of Arkansas, 118 Ozark Hall, Fayetteville, AR 72701, United States
Recommended Citation:
Goričan T.,Carter E.S.,Guex J.,et al. Evolutionary patterns and palaeobiogeography of Pliensbachian and Toarcian (Early Jurassic) Radiolaria[J]. Palaeogeography, Palaeoclimatology, Palaeoecology,2013-01-01,386