Species diversity, the ecology of wattled ibis (bostrychia carunculata) and land use cover change of chelekleka lake, bishoftu

... Organisation Record 19 95/30 Zhuravlev, A Yu 19 95 Preliminary suggestions on the global Early Cambrian zonation Beringeria Special Issue : 14 7 16 0  0 1- C1099 8 /10 /00 2:02 PM Page 4 Andrey Yu Zhuravlev and ... and radiation of major groups of organisms The focus is the Cambrian period (tables 1. 1 and 1. 2), but inevitably discussion of these topics also draw...

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... The problem of relating the two scales is complicated by the fact that the base of the Tommotian was taken as the base of the Cambrian at 570 Ma in Harland et al 1990 Since then, the Nemakit-Daldynian ... (19 92) , suggesting the Cambrian Early Ordovician evolution of these and other Southeast Asian fragments Although most of the boundaries of the fragment...

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... paleogeographic position 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 ... Yu Zhuravlev 1995 The Cambrian System of the Foldbelts of Russia and Mongolia International Union of Geological Sciences, Publication 32 Atlas of the...

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... period of the Late Neoproterozoic between the Marinoan glaciation at ca 600 Ma and the base of the Cambrian at ca 543 Ma) This involved the amalgamation of the separate 0 4- C1099 8/10/00 2: 04 PM ... crystalline rocks of the craton were uplifted and eroded, presumably as bulging of the crust and transgression of the platform proceeded Comparison of the 87...

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... are not, in themselves, climatic indicators (Crowell 1 957 , 1964; Heezen and Hol- 0 5- C1099 8/10/00 2: 05 PM Page 95 CLIMATE CHANGE AT THE NEOPROTEROZOIC -CAMBRIAN TRANSITION 95 Figure 5. 4 The Neoproterozoic ... Voo 1994) There are signs of four Neoproterozoic -Cambrian glacial periods (figures 5. 1– 5. 2): the Lower Congo (~900 Ma), the Sturtian (~ 750 –700 Ma), the Var...

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... subsequence of Southgate and Shergold (1991) The overlying subsequence 1a of these authors was separated on the basis of the occurrence of the Bronco Stromatolith Bed, ferrugi- 0 6- C1099 8/10/00 2: 06 PM ... 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 base...

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... facies, they form a more significant part of the stratigraphic record There is also an increase in the tax- 0 7- C1099 8/10/00 2:08 PM Page 163 THE CAMBRIAN RADIATION AND THE DIVERSIFICATION OF SEDIMENTARY ... Cambrian shell beds DISCUSSION The Cambrian represents a critical point in the development of nearly all biofabrics Near the base of the Cambrian, there...

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... predetermined the great Ordovician explosion In contrast to the Cambrian, the Ordovician radiation resembles that of the Mesozoic With the exception of the Bryozoa, 0 8- C1099 8/ 10/00 2: 08 PM Page 181 BIOTIC ... for the diverse Modern Evolutionary Fauna The power of a killing mechanism sufficient to destroy the biota (mass extinction) depends, prob- 0 8- C1099 8...

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... Flessa 199 5; Bambach and Bennington 199 6; Jablonski and Sepkoski 199 6); however, it is the taphonomic loss of “soft-bodied” constituents that stands as the overarching bias of the fossil record These ... and the structure of pelagic food webs Advances in Marine Biology 29 : 1–72 Knoll, A H 199 2 The early evolution of the 0 9- C1 099 8/10/00 2:10 PM Page 215 ECOLOGY...

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... nal deposi- 1 0- C1099 8 /10/ 00 2 :10 PM Page 227 EVOLUTION OF SHALLOW-WATER LEVEL-BOTTOM COMMUNITIES 227 tion on the bottom (Burzin 1996) Sabelliditid-like tube-dwelling Saarinidae were the rst animals ... typical of deltaic areas In the prograde delta-front sequence of the Chapel Island Formation of the Nemakit-Daldynian of Avalonia, the higher-energy environments s...

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... Palmer and Rozh- 1 1- C1099 8/10/00 2 :11 PM Page 245 EVOLUTION OF THE HARDGROUND COMMUNITY 245 Figure 11. 4 Positive feedback between the expansion of hardgrounds and the increase of calcite debris ... more above the sea floor The diverse 1 1- C1099 8/10/00 2 :11 PM Page 246 246 Sergei V Rozhnov Figure 11. 5 Maximum height of food-gathering apparatus above the sea flo...

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... 1992; Hofmann et al 1994) The purpose of this chapter is to review the progressive colonization of the deep sea from the Precambrian to the Ordovician, that is, through the period of Cambrian radiation ... (Seilacher 1989) There is, however, also a remarkable change in the style of preservation of many of the body fossils in passing across the Precambrian -...

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... appeared by the end of the Early Cambrian and inhabited hardgrounds and reefs from the Middle Cambrian The overall diversity of sponge and coralomorph types indicates that during the Cambrian these ... courtesy of Andrey Zhuravlev 1 4- C1099 8/10/00 2:13 PM Page 305 SPONGES, CNIDARIANS, AND CTENOPHORES 305 Soft-Bottom Communities of Sponges Most sponges are soft-b...

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... surprising diversity of early cephalopods, most of which had become extinct by the end of the Late Cambrian, is consistent with the explosive record of other Late Cambrian mollusks However, the data are ... representatives of the post -Cambrian order Paleoloricata (class Polyplacophora) and Matthevia The assignment of such forms to the Polyplacophora is questiona...

Ngày tải lên: 06/07/2014, 21:20