The Ecology of the Cambrian Radiation - Andrey Zhuravlev - Chapter 21 doc

... triaromatic 2-methyl-24-ethylcholesteroid; 10, triaromatic 4-methyl-24-ethylcholesteroid; 11, gorgosterol and 4a-methylgorgosterol; 12, 27-norcholest- 5,22-en-3b-ol; 13, 24-norcholest-5,22-en-3b-ol. 2 1- C1099 8/10/00 2:20 PM Page 475 484 ... radiation of di- noflagellates. Paleobiology 22:329–238. Goad, L. J. and N. W. Withers. 1982. The identification of 27-nor (24R )-2 4-methyl- c...

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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 ... 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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... 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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... distributed in the Ordo- vician. The time of their occurrence and wide distribution coincided with the Ordo- vician radiation of marine biota, which resulted in the replacement of the Cambrian Evolutionary ... interval for the study of the evolution of higher taxa of marine biota. One of the major radiations at high taxonomic level in the history of the...

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... led to the concept of “explosive evolution.” There are a sig- nificant number of short-ranging forms in the late Precambrian, but the Cambrian is dominated by much longer-ranging forms of Phanerozoic ... diversity at about the Pre- cambrian- Cambrian boundary, but the same is not true of trace fossils. There were a significant number of unusual short-ranging forms, many...

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... 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...

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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 ... [Facies and stratig- raphy of the Vendian and Cambrian of the western East-European Platform], pp. 24 – 33. Tallin: Academy of Sciences of Esto- nian SSR. Brasier, M....

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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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