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61.
Human and domesticate animal bone collagen δ15N values in prehistory differ generally by 3‰ or more from Neolithic to post- Roman times in Northwest Europe, leading to an assumed dietary animal protein fraction of 60–80% using a standard interpretation of δ15N values. We examine the assumptions on which this model rests and the limitations of our knowledge in the analysis of δ15N values in archaeology. We have developed a set of models which, with small changes made in assumptions (on the order of 1‰), can produce substantially lower estimates of the dietary animal protein fraction for given δ15N values. We consider the implications of various dietary animal protein fractions on agricultural carrying capacities and human population densities in prehistory. 相似文献
62.
Linda Courtenay Botterill 《Australian journal of political science》2007,42(1):33-46
In May 2005, the Commonwealth announced changes to the eligibility criteria for a number of farm welfare payments which have resulted in farmers receiving such payments on more generous terms than other disadvantaged groups in the community. The changes passed largely unremarked by the media or political commentators. Farm welfare programs are developed independently of the general welfare safety net and are based on assumptions about the nature, extent and causes of farm poverty. No comprehensive empirical research has been conducted into farm poverty since the Henderson Inquiry of the 1970s. This paper discusses the issue of farm poverty in Australia and how it fits into the broader welfare debate, and proposes a way forward to develop more effective and equitable farm welfare programs. 相似文献
63.
Level IV of Molodova I, an open-air Middle Paleolithic site in the Ukraine has been described by some researchers as a possible
source of evidence for early symbolic behavior. We examined bone objects from this layer that were identified by Ukrainian
researchers as exhibiting possible Neandertal produced engravings including two anthropomorphic figures. While we have determined
that there is no evidence of symbolic activity at Molodova I, the database we have created, with its systematic recording
of traces left by taphonomic agents on faunal remains, provides a better understanding of the overall site taphonomy. 相似文献
64.
Debora Zurro 《Archaeological and Anthropological Sciences》2018,10(7):1673-1691
The number of phytolith studies has increased steadily in the last decades in palaeoecological as well as archaeological research, and phytolith analysis is currently recognised as a proper area of expertise within archaeobotany. This has led towards a strengthening in the standardisation of the different steps involved in analysis; e.g. sampling strategies, laboratory extraction or processing of plant material/soils for the creation of reference collections. In spite of this, counting procedures remain one of the areas that could be further developed. The aim of this paper is to assess representativeness of phytolith count size in archaeological samples and specifically to assess whether an increase in total number of individuals counted influences the number or distribution of morphotypes observed. Two statistical tests are performed to evaluate the representativeness of count size: phytolith sum variability analysis (PSVA) and morphotype accumulation curve (MAC). The analyses show the relationship among the number of counted phytoliths, the variability (that is, the number of different morphotypes identified) and the stabilisations of the MACs. Results allow us to support the standard count size in phytolith studies, which ranges from 250 to 300 particles. Together with a quick scan, this strategy should produce a precise and clear phytolith assemblage for archaeological studies. 相似文献
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Matt A. White Alex G. Cook Scott A. Hocknull David A. Elliott 《Alcheringa: An Australasian Journal of Paleontology》2013,37(4):435-441
WHITE, M.A., FALKINGHAM, P.L., COOK, A.G., HOCKNULL, S.A. & ELLIOTT, D.A., 2013. Morphological comparisons of metacarpal I for Australovenator wintonensis and Rapator ornitholestoides: implications for their taxonomic relationships. Alcheringa 37, 1 - 7. ISSN 0311-5518.Various comparisons of left metacarpal I of the Australovenator wintonensis holotype have been made with Rapator ornitholestoides. These specimens were identified as being morphologically more similar than either was to that of the neovenatorid Megaraptor namunhuaiquii. Owing to the poor preservation of A. wintonensis and R. ornitholestoides, distinct morphological separation between the two appeared minimal. The recent discovery of a near perfectly preserved right metacarpal I of A. wintonensis enables a direct and accurate comparison with R. ornitholestoides. Distinct morphological differences exist between the metacarpals of the two species. A re-evaluation of the age of the A. wintonensis holotype site (AODL 85 ‘Matilda Site’) with zircon dating reveals a maximum age of 95 Ma, 10 Ma younger than the Griman Creek Formation at Lightning Ridge, from which R. ornitholestoides was recovered. This age difference detracts from the probability that the specimens belong to the same genus.Matt A. White? [fossilised@hotmail.com], School of Engineering, The University of Newcastle, Callaghan, New South Wales 2308, Australia; Peter L. Falkingham? [pfalkingham@rvc.ac.uk], Department of Comparative Biomedical Sciences, Structure and Motion Laboratory, Royal Veterinary College, London, UK; Alex G. Cook [alex.cook@y7mail.com] and Scott A. Hocknull [scott.hocknull@qm.qld.gov.au], Ancient environments, Queensland Museum, Hendra, Queensland, 4011, Australia; David A. Elliott [david.elliott@aaod.com.au], Australian Age of Dinosaurs Museum of Natural History, The Jump Up, Winton, Queensland, 4735, Australia. ?Also affiliated with Australian Age of Dinosaurs Museum of Natural History, The Jump Up, Winton, Queensland 4735, Australia. ?Also affiliated with Department of Ecology and Evolutionary Biology, Division of Biology and Medicine, Brown University, USA. Received 22.9.2012; revised 13.1.2013; accepted 17.1.2013. 相似文献
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