The Ecology of the Cambrian Radiation - Andrey Zhuravlev - Chapter 17 docx

... evolution of other Cambrian metazoans, the ecology of Cambrian trilobites remains poorly resolved. This chapter summarizes current knowledge of the ecology of Cambrian trilobite species and their ... the ecologic evolu- tion of these fossils. Recent interest in the Cambrian radiation has been fueled by the redescription of Cambrian soft-bodied organisms...

Ngày tải lên: 06/07/2014, 21:20

... 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 ... theme of community considers the biotas in their ecologic context, from their di- versification to the development of planktonic, level-bottom, reef, hardground, and deep-w...

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... 1995). 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. 1990. Since then, the ... interval; the substantial revision to the age of the base of the Cambrian period and other early Paleozoic stratigraphic boundaries; and, of course, the...

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... of the Innuitian Belt in the Cana- dian Arctic, which still await solution. There is no general agreement on the paleo- geographic boundaries of Siberia for the Vendian and Cambrian. The southern ... deposition in the late Precambrian–Early Cambrian Ara Forma- tion of Southern Oman. In A. H. F. Rob- ertson, M. P. Searl, and A. C. Ries, eds., The Geology and Tectonics o...

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... 1994. The period of evolution- ary failure and the dawn of evolutionary success: The record of biotic changes across the Precambrian -Cambrian bound- ary. In S. K. Donovan, ed., The Palaeobiol- ogy ... 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 Cen...

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... indicators of the climatic and environmental changes that occurred during the Neoproterozoic- Cambrian transition. They also appear to reveal the occurrence of a discrete cold period in the Cambrian: the ... Sinian. Together with increasing evidence for a renewed cold period in the Cambrian, the isotopic record suggests the unique nature of the period. On the bas...

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... 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 boundary ... 1992. Ion-probe zircon dating of a mid-Early Cambrian tuff in South Australia. Journal of the Geological Society of London 149:185–192. Daily, B. 1972. The bas...

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... beds. DISCUSSION The Cambrian represents a critical point in the development of nearly all biofabrics. Near the base of the Cambrian, there was a significant shift in the nature of sedimen- tary fabrics. ... 1994. The period of early evolutionary failure and the dawn of evo- lutionary success: The record of biotic changes across the Precambrian -Cambrian bound...

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... problems concerning the Precambrian -Cambrian boundary and the Cambrian fauna radia- tion. Journal of the Geological Society, Lon- don 149:593–598. Runnegar,B.1979. Originandevolutionof the class Rostroconchia. ... Middle and Late Cambrian, and Australian Datsonian as the terminal Cambrian interval (from the base of the proavus Zone to the base of the lindstromi...

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... 1996); how- ever, it is the taphonomic loss of “soft-bodied” constituents that stands as the over- arching bias of the fossil record. These typically unfossilized forms comprise a ma- jority of taxa ... of an early Paleo- zoic plankton and benthos, but they place the transition at the end of the Cambrian rather than the beginning. Certainly the Cambro-Ordovician tr...

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