The Ecology of the Cambrian Radiation - Andrey Zhuravlev - Chapter 19 pdf

... the Ordovician radiation of metazoans (Sprinkle 198 0). The purpose of this chapter is to review the ecologic radiation of Cambrian to Early Ordovician echino- derms and to analyze their diversification ... podia in the ambulacra were probably important respiratory struc- 1 9- C1099 8/10/00 2 :19 PM Page 437 Figure 19. 1 Reconstruction of soft-substrate echinoderm c...

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... distribution of organisms (Kidwell 199 0, 199 1). In that the Cambrian radiation is a critical event in the devel- opment of metazoan history, with the advent of skeletonization and the establishment of the ... and stratig- raphy of the Cambrian- Ordovician phos- phorite-bearing Obolus Unit on the north- west of the Russian Platform]. Leningrad: Nauka. Puura...

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... quality of seawater, thereby allowing the radiation of di- verse phototrophic communities (Zhuravlev chapter 8; Burzin et al. chapter 10); how the appearance of framework-building organisms created ... Aspects of the Cam- brian Radiation. In addition, this work has involved participants from IGCP Projects 303 (Precambrian -Cambrian Event Stratigraphy), 319 (Global Paleoge...

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... McKerrow 199 5). The prob- lem of relating the two scales is complicated by the fact that the base of the Tom- motian was taken as the base of the Cambrian at 570 Ma in Harland et al. 199 0. Since then, ... interval; the substantial revision to the age of the base of the Cambrian period and other early Paleozoic stratigraphic boundaries; and, of course,...

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... in the Cambrian. The Vendian -Cambrian succession of the Kolyma Uplift is characterized by species and facies typical of the Yudoma-Olenek Basin of the Siberian Platform (Tkachenko et al. 198 7). ... 50. On the whole, the late Middle Cambrian (Marjuman stage) was the time of the most intense tectonic activity in the Cambrian, coinciding with the peak of...

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... bulging of the crust and transgression of the platform proceeded. Com- parison of the 87 Sr/ 86 Sr record of the Ediacarian -Cambrian with that of the Cenozoic (Derry et al. 199 4) suggests that the ... Press. Crimes, T. P. 199 4. The period of evolution- ary failure and the dawn of evolutionary success: The record of biotic changes across the Precambri...

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... et al. 199 0; Kaufman et al. 199 3; Moores 199 3; Knoll 199 4; Kimura et al. 199 7). Almost without excep- tion, wherever there are signs of Neoproterozoic -Cambrian glacial influence, these oc- cur ... western South Amer- ica (Young 199 5) (figure 5.3). Eerola and Reis (199 5) and Eerola (199 6) called this zone the Varangerian-Sinian Glacial Zone, on the basis of the ages of...

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... 199 2). The boundary is placed at the base of the Wang- konda Formation and at the base of the trace fossil–bearing sandstones of the Winulta Formation in the Stansbury Basin. The Precambrian -Cambrian ... Australia. Journal of the Geological Society of London 149:185 192 . Daily, B. 197 2. The base of the Cambrian and the first Cambrian faunas. Unive...

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... October 199 5, Ab- stracts Book, pp. 42–43. Newell, N. D. 197 2. The evolution of reefs. Scientific American 226:54 –65. Nicholas, C. J. 199 6. The Sr isotopic evolu- tion of the oceans during the Cambrian Explosion.” ... 3:111–135. Rozanov, A. Yu. 199 2. Some problems concerning the Precambrian -Cambrian boundary and the Cambrian fauna radia- tion. Journal of the G...

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... to the introduction of mesozooplanktic grazing (Burzin 199 4; Butterfield 199 7). By establishing the second tier of the Eltonian pyra- mid in the pelagic realm, the Early Cambrian introduction of ... and Flessa 199 5; Bambach and Bennington 199 6; Jablonski and Sepkoski 199 6); how- ever, it is the taphonomic loss of “soft-bodied” constituents that stands as the o...

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