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1.
The origin of the genus Bos is a debated issue. From ∼ 0.5 Ma until historic times, the genus is well known in the Eurasian large mammal assemblages, where it is represented by Bos primigenius. This species has a highly derived cranial anatomy that shows important morphological differences from other Plio-Pleistocene Eurasian genera of the tribe Bovini such as Leptobos, Bison, Proamphibos-Hemibos, and Bubalus. The oldest clear evidence of Bos is the skull fragment ASB-198-1 from the middle Pleistocene (∼ 0.6-0.8 Ma) site of Asbole (Lower Awash Valley, Ethiopia). The first appearance of Bos in Europe is at the site of Venosa-Notarchirico, Italy (∼ 0.5-0.6 Ma). Although the origin of Bos has traditionally been connected with Leptobos and Bison, after a detailed anatomical and morphometric study we propose here a different origin, connecting the middle Pleistocene Eurasian forms of B. primigenius with the African Late Pliocene and early Pleistocene large size member of the tribe Bovini Pelorovis sensu stricto. The dispersal of the Bos lineage in Western Europe during middle Pleistocene times seems to coincide with the arrival of the Acheulean tool technology in this continent.  相似文献   

2.
The island fox (Urocyon littoralis) is one of few reportedly endemic terrestrial mammals on California's Channel Islands. Questions remain about how and when foxes first colonized the islands, with researchers speculating on a natural, human-assisted, or combined dispersal during the late Pleistocene and/or Holocene. A natural dispersal of foxes to the northern Channel Islands has been supported by reports of a few fox bones from late Pleistocene paleontological localities. Direct AMS 14C dating of these “fossil” fox bones produced dates ranging from ∼ 6400 to 200 cal yr BP, however, postdating human colonization of the islands by several millennia. Although one of these specimens is the earliest securely dated fox from the islands, these new data support the hypothesis that Native Americans introduced foxes to all the Channel Islands in the early to middle Holocene. However, a natural dispersal for the original island colonization cannot be ruled out until further paleontological, archaeological, and genetic studies (especially aDNA [ancient DNA]) are conducted.  相似文献   

3.
The Pleistocene record of East Asia continues to pose controversial questions for palaeoanthropology, especially with regard to Palaeolithic technological patterns. In recent years, an increased understanding of the effect of demography on cultural transmission has improved our understanding of the incidence, proliferation, and elaboration of technological traditions. Here, we present a generalised null model of Lower–Middle Palaeolithic technological evolution, which expressly links cultural transmission theory and demographic factors (i.e. population size, density, and social interconnectedness). Consistent with our model, Africa exhibits evidence of major technological innovations during the Early to Middle Pleistocene, due to a constant source of population and growth due to accumulation through time. In comparison, Pleistocene East Asian assemblages are dominated by Mode 1-type technologies, and only a few localized occurrences of bifacial technology are currently known. We detail evidence suggesting that during much of the Pleistocene a combination of biogeographical, topographical, and dispersal factors are likely to have resulted in relatively lower effective population sizes in East Asian hominins compared with western portions of the Old World, particularly Africa. Thus, the Movius Line – as is the case with its namesake ‘Wallace's line’ – must be examined in terms of its biogeographical context, if the divergent evolutionary trajectories of entities either side of it are to be understood. Most parsimoniously, the Movius Line sensu lato is thus a ‘line’ which represents the crossing of a demographic threshold. Under the parameters of our (testable) null model, geographically and temporally sporadic occurrences of bifacial technology in East Asia are the product of short-lived instances of technological convergence. As a consequence, the in situ evolution of Levallois (Mode 3) was inhibited in East Asia due to the constraints of relatively smaller effective population sizes.  相似文献   

4.
Sand-rich Holocene to modern clastic deposits in the eastern English Channel and the southern North Sea coasts of France and Belgium occur extensively as nearshore-sand bank, estuarine-tidal flat, aeolian dune and beach sub-environments. Sand samples (n = 665) collected from these deposits suggest the presence of three different populations: a largely dominant (83%) medium to fine quartz sand population (“b”), and finer- (14%) and coarser-grained (4%) populations (respectively “c” and “a”). The distribution of these populations among the four sub-environments reflects tide- and storm-dominated sorting and transport processes and a variable degree of mixing. These populations are derived from a mixture of very fine- to very coarse-grained fluvial, outwash and paraglacial sediments deposited on the beds of the eastern English Channel and southern North Sea during the late Pleistocene lowstand. The nearshore-sand bank environment, which also corresponds to the main offshore source area of the coastal deposits, exhibits population heterogeneity reflecting the variability of hydrodynamic conditions and sediment sorting in this zone. The nearshore topography of tidal ridges, banks and troughs in these tidal seas leads to variable bed and tide- and storm-induced shear stress conditions. These conditions only allow for the mobilisation and onshore transport of some of the finer fractions (populations “b” and “c”), leaving an offshore mixture of these finer populations with coarser, less mobilisable sediments (population “a”). Once in the coastal zone, these two finer populations undergo further hydrodynamic sorting and segregation. Variably sorted very fine sands to silts (population “c”) are trapped in the low-energy estuarine-tidal flat sub-environment, while the highly homogeneous population “b” is further sorted in aeolian dune and beach sub-environments. This sorting occurs via a coastal sand transport pathway linking the Somme estuary mouth to the southern North Sea bight where tidal range and wave energy decrease relative to the English Channel. Since this sand transport pathway enables longshore transport of hydrodynamically sorted medium to fine sand derived directly from the immediate nearshore zone, it has further contributed to a net flux of this sand population from the eastern English Channel sea bed to the southern North Sea.  相似文献   

5.
Field investigations at Dugway Proving Ground in western Utah have produced new data on the chronology and human occupation of late Pleistocene and early Holocene lakes, rivers, and wetlands in the Lake Bonneville basin. We have classified paleo-river channels of these ages as “gravel channels” and “sand channels.” Gravel channels are straight to curved, digitate, and have abrupt bulbous ends. They are composed of fine gravel and coarse sand, and are topographically inverted (i.e., they stand higher than the surrounding mudflats). Sand channels are younger and sand filled, with well-developed meander-scroll morphology that is truncated by deflated mudflat surfaces. Gravel channels were formed by a river that originated as overflow from the Sevier basin along the Old River Bed during the late regressive phases of Lake Bonneville (after 12,500 and prior to 11,000 14C yr B.P.). Dated samples from sand channels and associated fluvial overbank and wetland deposits range in age from 11,000 to 8800 14C yr B.P., and are probably related to continued Sevier-basin overflow and to groundwater discharge. Paleoarchaic foragers occupied numerous sites on gravel-channel landforms and adjacent to sand channels in the extensive early Holocene wetland habitats. Reworking of tools and limited toolstone diversity is consistent with theoretical models suggesting Paleoarchaic foragers in the Old River Bed delta were less mobile than elsewhere in the Great Basin.  相似文献   

6.
The first occurrence and presence of the bivalve Macoma balthica in the Pleistocene shallow marine sediments (Crags) of East Anglia has long been used to characterise the youngest “Weybourne” or “Wroxham” Crag Formation of Early to early Middle Pleistocene age. A review of recent work on the morphological variation and genetic lineages of living populations of the species and of work on fossil discoveries in East Greenland suggests that the current palaeontological species definition is too narrow, that the species arrived in the Atlantic about 2.4 Ma and much earlier than is envisaged from the studies of the North Sea Basin, and that there were several trans-Arctic migrations of the species during the Pleistocene. This paper reviews these findings and concludes that: (i) detailed morphometric analyses of fossil Macoma species from the Crag need to be undertaken and the species definitions comprehensively reviewed to take account of the morphological and genetic variation seen in modern populations; (ii) detailed morphometric analysis of modern M. balthica should be undertaken and tied to the different genetic lineages, and (iii) the current palaeontological definition of Macoma balthica should not be relied on as the basis for a First Appearance Datum (FAD) in the Southern North Sea basin.  相似文献   

7.
During the late Pleistocene and early Holocene, Bison was widely dispersed across North America and occupied most regions not covered by ice sheets. A dietary study on Bison paleopopulations from Alaska, New Mexico, Florida, and Texas was performed using two methods that relate dental wear patterns to diet, mesowear analysis and microwear analysis. These data were compared to a mixed sample of extant Bison from the North American central plains, extant wood Bison from Alberta (Canada) and a variety of other modern ungulates. Mesowear relates macroscopic molar facet shape to levels of dietary abrasion. The mesowear signature observed on fossil Bison differs significantly from the hyper-abrasive grazing diet of extant Bison. Tooth microwear examines wear on the surface of enamel at a microscopic scale. The microwear signal of fossil samples resembles to modern Bison, but the fossil samples show a greater diversity of features, suggesting that fossil Bison populations regularly consumed food items that are texturally inconsistent with the short-grass diet typical of modern plains Bison. Mesowear and microwear signals of fossil Bison samples most closely resemble a variety of typical mixed feeding ungulates, all with diets that are substantially less abrasive than what is typical for modern plains Bison. Furthermore, statistical tests suggest significant differences between the microwear signatures of the fossil samples, thus revealing geographic variability in Pleistocene Bison diets. This study reveals that fossils are of value in developing an understanding of the dietary breadth and ecological versatility of species that, in recent times, are rare, endangered, and occupy only a small remnant of their former ranges.  相似文献   

8.
Pleistocene alluvium along Little Kettle Creek in east-central Georgia contains a unique record of vertebrate life in the Appalachian Piedmont during a colder phase of the late Quaternary. The small fauna includes fishes and the following mammals: Synaptomys cooperi, the southern bog lemming; Clethrionomys sp., a redback vole; Mammut americanum, the American mastodon; a mammoth, Mammuthus sp.; Odocoileus cf. virginianus, a deer; and Bison sp. Both Synaptomys and Clethrionomys are primarily boreal genera of rodents which today reach their southern limits at higher elevations in the Great Smoky Mountains about 175 km north of the fossil locality. The American mastodon is also commonly associated with Pleistocene spruce bogs in eastern North America. Catfish (Ictalurus (?) sp.) vertebrae from the deposit show well-defined annual rings in contrast with the weakly marked annuli produced by fish living in the same area today. The total aspect of the fauna is one of considerably lower temperatures than those prevailing in the Georgia Piedmont now. The joint occurrence of bison and proboscideans indicates an age no older and no younger than late Pleistocene (Rancholabrean) for the assemblage. Because no pollen was found in the sediments and there was insufficient organic matter present for 14C dating, no more precise age can yet be assigned to the fauna.  相似文献   

9.
In Mexico, just 54% of the reported Pleistocene Bison material has been identified to species. Current paleontological research in northwestern Oaxaca, southern Mexico, has allowed collection of several specimens of Bison antiquus that are part of the Viko Vijin Local Fauna. B. antiquus had a very wide geographic distribution, from lowlands to mountainous landscapes of North and Central America. The B. antiquus record from southern Mexico links their former records from central Mexico and middle Central America and confirms this wide geographic distribution. The univariate mesowear score of the B. antiquus specimens from Oaxaca is in the lower extreme of grazers and the upper end of mixed-feeders, suggesting that they had a less abrasive diet than the modern plains Bison, as has been observed in other samples of this species from diverse parts of North America. The presence of B. antiquus in the Viko Vijin L. F. constrains the age of this fossil assemblage within a range from 60 Ka to 11.7 Ka.  相似文献   

10.
In Xishuangbanna, southern Yunnan, Akha and Dai farmers, regarded in China as “backward”, passive recipients of state-led development, have been “getting rich” on rubber and expanding rubber cultivation into neighbouring Laos. State cash crop campaigns to raise minority farmers’ incomes inadvertently turned minority farmers into dynamic entrepreneurs. This paper builds on Vinay Gidwani’s use of development as a “regime of value” to raise social and economic value to analyze these unexpected results. Local state agents believe they are the agents of development, bringing modest social and economic improvements to minority farmers of obdurate backwardness. Minority farmers see themselves as improving their own incomes and “quality”, a term in China for social value, in an era when they are responsible for their own development. National development discourse encourages citizens to raise population quality by becoming entrepreneurial, a message heard by minority rubber farmers as well as urban elites. Through creative, post-Fordist production models and agile deployment of land, labour, and capital, minority farmers have achieved incomes that exceed those of workers on state rubber farms, large plantations whose Fordist production models are losing out in the uneven transition from a planned economy to a more capitalist market assemblage. Akha and Dai rubber farmers, the “backward” minorities on China’s periphery, have unexpectedly become the forerunners of flexible production arrangements that are prevailing in the arena opened up by China’s 2001 entry into the World Trade Organization.  相似文献   

11.
Gail M. Hollander 《Geoforum》2004,35(3):299-312
This paper explores the applicability of the concept of “multifunctionality” to the south Florida sugar-producing region. Multifunctionality is being promoted in the European Union in response to neoliberal trade pressures in agriculture. It is seen as a way to address social and ecological concerns such as farm abandonment and biodiversity loss through domestic agricultural policies that conform to the GATT/World Trade Organization. I have two objectives in this paper. First, I seek to investigate multifunctionality as one response to neoliberal pressures for agricultural reform. In doing this, I identify two types of multifunctionality, a “weak” and a “strong” version. Second, I want to explore the possibility for multifunctionality to serve as a vehicle for resistance to GATT/WTO in other regions. I do this through a study of arguably the most maligned agricultural zone in the world, the sugar-producing region of south Florida. The specific geographic focus is the Everglades Agricultural Area (EAA), the federally designated, 700,000-acre zone south of Lake Okeechobee that is home to the Florida “Sugar Bowl.”  相似文献   

12.
Eric D. Carter 《Geoforum》2008,39(1):278-293
Recently, geographers and other scholars have reappraised the state’s spatial properties, roles, and strategies. According to these interpretations, modern states seek to control their subjects and coordinate economic development through various “rational” and “scientific” strategies that involve the standardization, transformation, and bureaucratization of space, territory, and landscape. Through this process social relations are increasingly configured through state discourses and institutions. The role of public health institutions in the development of state spatialities has been relatively underappreciated. This paper explores the establishment and early action of a malaria control campaign in Northwest Argentina, in the early twentieth century. I make three arguments: first, in creating a malaria control program, the Argentine state did not merely respond to a given “social fact” but rather was the key participant in constructing the “malaria problem”. Second, in response to this problem the Argentine state created a new technical-administrative territory, “the malarious zone”, which encompassed several provinces and defined the federal government’s jurisdiction for public health action. Finally, state actors came to understand the malaria problem, and potential solutions to it, through specific “rational” practices of the modern state: surveying, mapping, measurement, and statistical compilation. In its early years, the malaria campaign did not so much control the disease itself, as much as establish control over the “malaria question”, making it indisputably a state project.  相似文献   

13.
Political ecologists working in many other parts of the world are now heading north, or simply going global, posing a series of important questions related to theory, methodology, politics, and policy along the way. This special issue, contains papers originally delivered at a conference held at Rutgers University in 2003 that addressed this phenomenon. The papers collected offer case studies that reveal the First World as subject to a host of processes that can be insightfully understood via a political ecology perspective. First, globalized production and consumption regimes have created new linkages that demand synoptic analyses of often far-flung research sites. Second, the painful coincidence of deindustrialization and a radical restructuring of agricultural credit and price support systems have devastated North American and European heartlands, effectively producing “Third World” conditions in many depressed rural areas. Third, migration streams originating in Latin America, Africa and many parts of Asia have brought sizable Third World populations into the spatial heart of capitalism. Fourth, the belated recognition of some indigenous claims to resources, especially in Canada, and fierce opposition to others, have reopened questions of (internal) colonial domination. Finally, we see the burgeoning First World political ecology literature as the culmination of what Louise Fortmann has called “the long intellectual journey home” for many scholars who originally carried out research on/in the Third World. All of these factors have combined to help political ecologists discover suitable analytical terrain in the First World.  相似文献   

14.
更新世中期是全球气候和环境变化的一个重要时期，当时气候周期转型，全球冰量增加，海平面下降，哺乳动物迁徙或灭绝，这个时代也是直立人地理大扩张和手斧文化扩散的一个重要时期，这些事件在发生时间上的统一性指示它们之间的某种联系，推测更新世中期全球性的气候转变是这次手斧文化扩散的主要驱动力，中国百色盆地发现的手斧可能是西方阿舍科技术向东渗透或扩散的结果。  相似文献   

15.
The burgeoning literature on transnationalism involving skilled migrants--based largely on the view from the developed world--have generally paid little heed to “elite” women and the reproductive sphere. We argue that women play many roles in elite transnational migration streams and must be given full consideration as part of the “transnational elite.” Attention is given to the way women--both “tied” and “lead” migrants--negotiate gendered identities as they participate in Singapore's regionalisation process, a state-driven initiative to extend the national economy by leveraging on growth in the region. Empirical material for the paper is mainly based on in-depth interviews with married women who were part of a larger project involving interviews with 150 Singaporeans who had lived, or were living, in China. In examining the movements through transnational space between Singapore and China, it is clear that patriarchal norms continue to shape women's understandings of their own identities vis--vis men's. Singapore women who move as accompanying spouses (the majority) find themselves giving up careers to focus on their domestic role in China (in the absence of access to “suitable” paid domestic service), and are not so much “deskilled” but “re-domesticated”. The exceptional few women who ventured into China as entrepreneurs experienced considerable strain holding together geographically separate spheres of productive and reproductive work across the transnational terrain. Both sets of “stories” alert us to the need to include “elite” women--whether accompanying spouses or independent entrepreneurs--in our understanding of “transnational elites.” This will contribute to the urgent task of ensuring that both productive and reproductive work are valorized in equal measure in conceptualizing transnationalism.  相似文献   

16.
The rich Quaternary fossil record from the Cantabrian region (NW Iberia) is virtually restricted to the Late Pleistocene, with Middle Pleistocene findings very rare. This work presents the study of two Middle Pleistocene palaeontological sites in the Cantabrian region: Llantrales quarry and Mestas de Con mine, both discovered and first described in the 1950s but never studied in detail thereafter. The material was here re‐analysed and re‐evaluated. Taxonomic attributions have been changed in most cases and, consequently, chronological assignments of the fossils have also been changed. This first detailed study of the assemblage from Llantrales quarry revealed the occurrence of the large‐sized deer Praemegaceros solilhacus, which has never been reported previously in North Iberia. Cervus cf. elaphus and Stephanorhinus cf. hundsheimensis were also identified. The age of these fossils was originally regarded as Pontian (late Miocene), but new palaeontological results indicate a much younger age, most likely from around 0.8 to 0.5 Ma. A taxonomic re‐evaluation of the fossils from Mestas de Con provided different results with respect to the 1950s works. The faunal association is composed of a large‐sized deer (probably corresponding to Praemegaceros), Cervus elaphus, Capreolus cf. capreolus, Bison sp. (small sized), Equus sp. (large sized), Stephanorhinus hemitoechus, Ursus sp. and Homotherim latidens. This faunal association was evaluated within a western European context and proves to be highly analogous to other contemporary assemblages there. The chronology was initially regarded as late Villafranchian (in a broader sense). New results, documenting the co‐occurrence of Stephanorhinus hemitoechus and Homotherium latidens, indicate a more precise and younger age, most likely between 0.6 and 0.4 Ma. These two fossil assemblages provide new and relevant information on the Middle Pleistocene faunas from a geographical region where this information, compared with other western European areas, is rare and poorly known.  相似文献   

17.
In the US, the Ford Foundation’s Community-based Forestry Demonstration Program (2000-2005) promoted an internationally prominent model of community forestry centered on the simultaneous, balanced pursuit of ecological, economic and social goals (often symbolized as the “three-legged stool,” or “triple bottom line”). This paper develops an alternative framework for analysis that emphasizes the causal precedence of shifts in power relations, specifically the devolution of resource access and decision-making authority, rather than environmental, social and economic outcomes. These outcomes are not necessarily beneficial, and any benefits realized seldom occur simultaneously. Rather, they can be envisioned as the floors of a house erected sequentially on a foundation of resource access and control. While no universal claim is made, the “house” model proves an apt fit for many community-based forestry initiatives, including the two case studies presented. Who among the differentiated social groups within a community gained access to resources and decision-making influence largely predicted who gained individually. Nonetheless, indirect benefits felt at community and higher scales were significant. The findings further indicate that community forestry generally will not advance social equity unless it specifically targets marginalized groups. Crucially, equity is understood to embrace not only distributional justice, but also capacity-building and empowerment.  相似文献   

18.
Precipitation and net primary productivity are positively correlated in arid environments. Both variables are, in turn, correlated with mammal species richness, but this relationship is not necessarily positive. With increasing precipitation in arid areas of low to moderate productivity, mammal richness increases linearly; as rainfall and productivity increase beyond this point, mammal richness is known to decline in some areas, producing a relationship that has been termed “unimodal” or “humped.” In the Great Basin of the arid western United States, studies of the relationship between rodent species richness and precipitation have revealed only a positive relationship between these two variables. It has, however, been argued that if areas of higher precipitation were to be sampled within this region, the decline phase would become evident. When latest Pleistocene and Holocene small mammal assemblages from the northern Bonneville Basin (central Utah) are examined across a temporal moisture gradient, species richness declines as moisture declines. Since the Great Basin was significantly moister during the latest Pleistocene and Early Holocene than it has been since that time, the unimodal response model does not appear to apply to this region.  相似文献   

19.
B. McCusker  E.R. Carr 《Geoforum》2006,37(5):790-804
Land use change and livelihood systems are often analyzed separately or with one “driving” the other. This “driver-feedback” relationship has been buttressed by approaches to social process that are often far too static. Actors are confronted with a bundle of choices that they must negotiate as they create pathways of change. These choices are always bound up in relations of power and the knowledges that are the conditions for and results of these relations. We suggest that land uses and livelihood are different manifestations of the social processes by which individuals and groups negotiate the everyday conditions that shape their lives. We propose a framework that extends current understandings of the relationship between land use change and livelihoods by treating social relations of power as the entry point into this complex relationship. We underpin our arguments with empirical examples from South Africa and Ghana that locate power/knowledge relations in the context of social change in both study areas.  相似文献   

20.
Discoveries of fossil Homo outside Africa predating 1.0 Ma have generated much discussion about hominin dispersal routes. However, tool-using bipeds were only one element of the inter-continental mammalian dispersals that occurred during the climatic changes of the Pliocene and Pleistocene. This paper will place hominin movements in the context of those of the wider mammalian fauna, which includes carnivores, bovids and non-human primates. The distribution of these different taxa suggests that species moved individually when the environmental conditions were right for them, rather than in multi-species waves of dispersal, and allows evaluation of the contextual evidence for the newly emerging ‘Out of Asia’ paradigm as well as the established ‘Out of Africa’ model.  相似文献   

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