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Alex G. Cook Robert B. Blodgett R. Thomas Becker 《Alcheringa: An Australasian Journal of Paleontology》2013,37(3):181-207
Over 50 identifications of Tertiary pollen are reviewed. The pollen assemblages indicate rain-forest through most of the Tertiary, but the requisites for pollen preservation are biased towards the wetter climates. The present day geographical affinities of the botanical groups are largely with taxa of the tropical zone and Australia-wide taxa. There is geographic variation in the fossil pollen assemblages when southeastern Australia is compared with Central Australia and Queensland. The major changes in the fossil floras coincide with climatic change, indicating the influence of climate on the evolution of plant assemblages. The older phytogeographic concepts are inappropriate for the fossil record, especially when considered in conjunction with palaeoclimates and palaeogeography. It is unfortunate that palynology has given little information of the evolution of floras in drier climatic regimes, or of the evolution of the eucalypts. 相似文献
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Neil S. Davies Ivan J. Sansom Robert S. Nicoll Alex Ritchie 《Alcheringa: An Australasian Journal of Paleontology》2013,37(4):553-569
The Stairway Sandstone is a 30–560 m thick succession of Middle Ordovician siliciclastic sedimentary rocks within the Amadeus Basin of central Australia, deposited in the epeiric Larapintine Sea of northern peri-Gondwana. The Stairway Sandstone is significant as one of only two known Gondwanan successions to yield articulated arandaspid (pteraspidomorph agnathan) fish. Herein we use the ichnology of the Stairway Sandstone to reveal insights into the shallow marine habitat of these early vertebrates, and compare it with that of other known pteraspidomorph-bearing localities from across Gondwana. The Stairway Sandstone contains a diverse Ordovician ichnofauna including 22 ichnotaxa of Arenicolites, Arthrophycus, Asterosoma, Cruziana, Didymaulichnus, Diplichnites, Diplocraterion, ?Gordia, Lockeia, Monocraterion, Monomorphichnus, Phycodes, Planolites, Rusophycus, Skolithos and Uchirites. These ichnofauna provide a well-preserved example of a typical Ordovician epeiric sea assemblage, recording the diverse ethologies of tracemakers in a very shallow marine environment of flashy sediment accumulation and regularly shifting sandy substrates. New conodont data refine the age of the Stairway Sandstone to the early Darriwilian, with ichnostratigraphic implications for the Cruziana rugosa group and Arthrophycus alleghaniensis. 相似文献
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Rachel Black 《Journal of Modern Italian Studies》2013,18(2):184-198
Abstract Water is an important part of most Italian meals, and Italians are amongst the largest consumers of bottled mineral water in Europe. This article looks at the development of the mineral water industry in Italy from the nineteenth century to present by focusing on the case of Sangemini mineral water from Umbria, Italy. In particular, this article looks at how medical findings became part of a popular hygiene and health discourse that was central to developing a market for mineral water in Italy. Contrary to other international markets, bottled mineral water is still consumed in Italy for its health and nutritional benefits today. 相似文献
56.
Alex Gibson Sheena Asthana† 《Transactions (Institute of British Geographers : 1965)》2000,25(3):303-319
Notwithstanding the recent change of government, UK educational policy continues to stress school performance tables, parental choice and competition – reflecting an acceptance by New Labour of Tory notions concerning the role that market mechanisms play in improving school performance. In view of the 1997 Education White Paper's insistence that the new government's goal was to 'overcome the spiral of disadvantage … passed from one generation to the next', this implies that the DfEE remains unimpressed by long-standing arguments concerning the socially-divisive consequences of market forces in education.
This paper seeks to add empirical weight to this debate. Arguing that recent analyses of aggregate levels of social stratification have masked polarization occurring at the local level, our analysis places schools in the context of the local markets within which they operate. This yields clear evidence that educational markets tend to exacerbate existing differences between schools in terms of both their performance and social status. 相似文献
This paper seeks to add empirical weight to this debate. Arguing that recent analyses of aggregate levels of social stratification have masked polarization occurring at the local level, our analysis places schools in the context of the local markets within which they operate. This yields clear evidence that educational markets tend to exacerbate existing differences between schools in terms of both their performance and social status. 相似文献
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