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121.
The Bayesian linear mixing model SISUS is used to reconstruct reliance on maize and intake of animal protein from the stable carbon (δ13C) and nitrogen (δ15N) isotope values of 149 directly dated Basketmaker II burials. Maize is the primary dietary staple. δ13C values are also enriched by intake of yucca and wild C4 plant foods but these resources are of minor importance in sampled diets. Animal protein intake is low and cottontail rabbits make the greatest contribution to female diets. Adolescent diets are indistinguishable from the diets of adult females and both groups are less reliant on artiodactyls than males. The δ13C and δ18O values of bone hydroxyapatite distinguish nursing infants and oxygen isotope values identify outsider adults relative to those local to the region where their deaths occurred. Most Utah Basketmaker II burials are contemporary with Black Mesa Lolomai phase occupations, postdating the Marsh Pass, AZ, White Dog phase. All burials in both studies were recovered from sheltered rather than open sites and reliance on maize does not increase over the temporal span of the Utah study, covering the two sigma range 415 BC–AD 322.  相似文献   
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In the debate over Western Europe??s Middle to Upper Palaeolithic transition we need to consider the importance of both the chronology and the ecological context of the different techno-complexes, as well as the organization of production and consumption activities. In this article we study the adaptative strategies of Middle Palaeolithic human communities based on the information obtained from archaeological sites north of the river Ebro. This transition in the northern part of the peninsula presents a chronological and geographic dichotomy, with the appearance of the Upper Palaeolithic and survival of the Middle Palaeolithic. The geographic distribution appears to indicate intergroup competition and the existence of contact, albeit of an unverified nature. This competition would explain the time that elapsed before one of the cultural, and perhaps biological, groups triumphed over the other in a process culminating in the expansion of Upper Palaeolithic technology.  相似文献   
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Our ongoing investigation of early maize farming in the American Southwest has entailed stable isotope analysis and accelerator radiocarbon dating of Basketmaker II remains from sites in the Four Corners region. Here we report radiocarbon dates on a large mortuary assemblage excavated by Richard Wetherill in 1893 from a burial cave in southeastern Utah. It has long been thought that all individuals interred in Cave 7 were massacred in a single violent attack given embedded projectiles and evidence for blunt force trauma. However, accelerator radiocarbon dates on purified bone collagen (n = 96) do not lend strong support to this argument, even among the subset of individuals with clear evidence for violent injuries. Moreover, nearly 80% of Cave 7 burials examined in the study show no evidence of perimortem trauma and no adult females or subadults under the age of 12 appear to have suffered violent deaths. Rather than an anomalous single-event massacre, the Cave 7 radiocarbon dataset suggests that raiding and intra-group, male/male violence was episodic among Basketmaker groups in southeastern Utah. Population densities were relatively high and individuals interred in Cave 7 and elsewhere in the region were heavily dependent on maize agriculture, a prehistoric economic strategy typically characterized by high amplitude fluctuations in productivity. Variability in the array of grave goods accompanying Cave 7 male burials and elsewhere suggests competitive social differentiation likely heightened during periods of resource shortfall leading to intra-group conflict, raiding and perhaps ritualized acts of violence.  相似文献   
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The reasons for megafaunal extinction in Australia have been hotly debated for over 30 years without any clear resolution. The proposed causes include human overkill, climate, anthropogenic induced habitat change or a combination of these. Most protagonists of the human overkill model suggest the impact was so swift, occurring within a few thousand years of human occupation of the continent, that archaeological evidence should be rare or non-existent. In Tasmania the presence of extinct megafauna has been known since the early twentieth century (74, 85 and 86) with earlier claims of human overlap being rejected because of poor chronology and equivocal stratigraphic associations. More recent archaeological research has not identified any megafauna from the earliest, exceptionally well-preserved late Pleistocene cultural sites. In 2008 however an argument for human induced megafaunal extinctions was proposed using the direct dates from a small sample of surface bone from two Tasmanian non-human caves and a museum sediment sample from an unknown location in a cave, since destroyed by quarrying (Turney et al., 2008). Turney et al. (2008) supplemented their data with published dates from other Tasmanian caves and open sites to argue for the survival of at least seven megafauna species from the last interglacial to the subsequent glacial stage.  相似文献   
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Due to the concentration of Australian Labor Party voters, that party has to poll more votes than the Liberal and National Parties to win an election. That is not a gerrymander, for no matter how fairly the boundaries were drawn, Labor would still need to poll more votes than its opponents under the preferential, single‐member constituency voting system. Nevertheless, even under perfectly fair electoral redistributions, Labor is bound to come off worst because Labor voters are more highly concentrated than non‐Labor voters.  相似文献   
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Since the Commonwealth Electoral Commission is issuing full distribution of the preferences of votes for minor candidates at elections for the House of Representatives, it is now possible to assess the use of these and compare them with previous estimates. This paper therefore looks at the concept of the ‘two‐party preferred vote’ in the light of such publication and the introduction of optional preferential voting in New South Wales.  相似文献   
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