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91.
Animal dung is evaluated here as a tool to reconstruct recent societal and environmental changes. Studies completed on the macro- and micro-contents from dung deposited in a mountain cave in Catalonia during the 1970–1980s, preceding the socio-economic changes in the area, was supplemented by the testimony of the last shepherd alive in the area. This information was also compared with evidence from aerial photographs of the area surrounding the cave taken in 1956 and 2009. Although taphonomic distortion of the dung shape precluded its assignment to its producers based on morphology, information from the organic remains reflects the agro-pastoral activities in the mountainous area of the Catalan coast. A lack of calcium phosphate and abundant phytolith and epidermal remains from wild species indicates that the dung was excreted by ovicaprines, who sheltered in the cave during spells of adverse weather. These indicators also signify that the animals fed only on natural vegetation. Insect remains in the dung include fragments of chafers, dung and ground beetles, bees and ants, and whilst the latter may have foraged in the cave, the others may have been accidentally ingested by herbivores. The nannofossils and diatoms found in the dung derive from tertiary crops 4 km away from the cave but within the range of the ovicaprine herd. The lack of cereal and vegetable remains in the dung is consistent with the ethnographic record that shepherds and farmers could not afford to supplement the herds’ diet with fodder crops or grain, a consequence of the low productivity of the local subsistence agriculture. This study further discusses the socio-economic impacts of the introduction of intensive farming, industrialisation and tourism in Catalonia during the latter part of the last century and how they are represented in the dung.  相似文献   
92.
In archaeology, data obtained from the analysis of material evidence (i.e., the archaeological record) from extensive excavations have been a significant means for the ultimate development of interpretations about human life in the past. Therefore, the methodological procedures and tools employed during fieldwork are of crucial importance due to their effect on the information likely to be recovered. In the case of maritime archaeology, the development of rigorous methods and techniques allowed for reaching outcomes as solid as those from the work performed on land. These improvements constituted one of the principal supports—if not, the most important pillar—for its acceptance as a scientific field of study. Over time, the growing diversity of sites under study (e.g., shipwrecks, ports, dockyards, and prehistoric settlements) and the underwater environments encountered made it clear that there was a need for the application of specific methodological criteria, in accordance with the particularities of the sites and of each study (e.g., the research aims and the available resources). This article presents some ideas concerning the methodologies used in South American investigations that have exhibited a strong emphasis on the analysis of historical shipwrecks (the sixteenth to twentieth centuries). Based on a state-of-the-knowledge review of these research projects, in particular where excavations were conducted, the article focuses on the details of the main strategies adopted and results achieved. The ideas proposed in this article can be useful as a starting point for future activities of surveying, recording, and excavating shipwrecks.  相似文献   
93.
Economic growth in China in recent decades has largely rested on the dynamism of its cities. High economic growth has coincided with measures aimed at improving the efficiency of local governments and with a mounting political drive to curb corruption. Yet the connection between government institutions and urban growth in China remains poorly understood. This paper is the first to look into the link between government efficiency and corruption, on the one hand, and urban growth in China, on the other hand and to assess what is the role of institutions relative to more traditional factors for economic growth in Chinese cities. Using panel data for 283 cities over the period between 2003 and 2014, the results show that the urban growth in China is a consequence of a combination of favorable human capital, innovation, density, local conditions, foreign direct investment, and city‐level government institutions. Both government quality—especially for those cities with the best governments—and the fight against corruption at the city level have a direct effect on urban growth. Measures to tackle corruption at the provincial level matter in a more indirect way, by raising or lowering the returns of other growth‐inducing factors.  相似文献   
94.
This article investigates the incidence of agglomeration externalities in Ecuador, a small-sized, middle-income developing country. In particular, we analyze the role of the informal sector within these relations, since informal employment accounts for a significant part of total employment in the developing countries. Using individual level data and instrumental variable techniques, we investigate the impact of spatial externalities, in terms of population density, local specialization and urban size, on the wages of workers in Ecuadorian cities. The results show that spatial externalities matter also for a small developing country. Moreover, analysis of the interaction between spatial externalities and informality shows that, on average, workers employed in the informal sector do not enjoy significant benefits from agglomeration externalities. Finally, by investigating the possible channels behind spatial agglomeration gains we show that the advantages from agglomeration for formal sector workers may well be accounted for by better job-quality matches and, to a lesser extent, by learning externalities. For informal sector workers, our findings also suggest possible gains from job changes, which offset a penalty for remaining employed in the same occupation.  相似文献   
95.
The role of cities in fostering innovation has for long been taken for granted. Agglomeration and the knowledge spillovers generated in dense urban environments have been considered fundamental drivers of innovation. This view has, however, become challenged by research questioning the returns to physical agglomeration and local networking, placing instead more emphasis on the importance of interregional and international collaboration, and on innovation in peripheral regions. This paper delves into the debate on the role of cities for innovation by examining the interplay between urban location and local collaboration in Norway. It uses data from the Community Innovation Survey for 2006–2010 to map out the geographical dimension of R&D collaboration in Norwegian firms with a view to assessing whether different types of R&D collaboration in urban and rural locations affect firms’ propensity to innovate. The results show that local collaboration is associated with increased process and organisational innovation, while it does not produce higher levels of product or marketing innovation. Conversely, international collaboration is connected with higher probabilities of product, new-to-market and marketing innovations. Furthermore, location in urban or rural areas makes no difference for most innovation outcomes in Norway when other characteristics are controlled for. Location in cities also does not shape the returns to local R&D collaboration. Hence, the role of cities for innovation in Norway, whether in themselves or as sites for dense local interaction, is less relevant than the urban innovation literature would predict.  相似文献   
96.
The study of the fish bones from the Neolithic shell midden of Suwayh 1, excavated in the 2000s, identified a total of 1060 identifiable fish bones, from 23 families, 33 genera and 28 different species. Radiocarbon dating demonstrates that the sites date to the early 6th to mid 5th millennium BC. The results follow an eight-phase chronology highlighted by an earlier malacological study. The most important taxa were the Carcharhinidae (requiem shark), Rhinopteridae (cownose rays), Sparoidea (Sparidae and Lethrinidae: sea breams and emperors) and Ariidae (sea catfishes). The results of the fish study show that the Suwayh lagoon must have gradually opened up to the sea and been populated with mangroves. The unique presence of so many sharks at this site seems to indicate that the inhabitants had a special interest in shark fishing and that their location was ideal for this specialised activity. Two types of fishing nets and hooks have been discovered, which require the use of different fishing techniques.  相似文献   
97.
African Archaeological Review - The emergence of socio-political differentiation is a core theme in world prehistory, and the West African archaeological record offers unique insights into the...  相似文献   
98.
This article discusses the legacy of Amílcar Cabral. The main question it deals with is how to read Cabral today when the system that prompted the emergence of his theory, colonialism, is no longer there. The main argument of this article is, therefore, that a disjuncture exists in the ways Cabral is discussed today. Cabral was certainly a great nationalist and revolutionary, and his contribution crucial for the ways in which revolution in Africa has been apprehended. However, his theoretical contribution should be ascertained alongside the analyses of the realities his emancipatory project addressed. Basically, this article suggests a reading of Cabral's theory in the context of the practices and context his theory was addressing. For doing this, this article examines the main tenets of Cabral's theory, on nationalism, alongside the responses the Portuguese had come up with under the rubric of counter-insurgency strategies. The contribution this article tries to put forward is that critical purchase in reading Cabral today has to take into account the complexities of the anticolonial past that brought us to our postcolonial present.  相似文献   
99.
The construction of large-scale long-distance roads brings an irreversible impact on the landscape and therefore its careful and precise planning is very important. For this planning we use data on the intensity of traffic flows on existing roads and statistical tools for the modeling of planned traffic flows. The main objective of this paper is the modeling of the existing intensity of traffic flows on highways and expressways in the Czech Republic by determination of the optimal distance-decay function. On the basis of the resulting model and the resulting distance-decay function, it is possible to predict the intensity of traffic in the event of the completion and commissioning of new sections of highways and expressways. The subsequent analysis will allow us to make a qualified prediction of traffic intensity in the event of the completion of the R35 expressway, or after the completion of the R35 and R43 expressways. Besides the intensity on the above-mentioned roads themselves, the paper also predicts the expected reduction in traffic intensity on the busiest highway in the Czech Republic, that is, on the D1 highway between Prague and Brno.  相似文献   
100.
Ubilla, M. & Rinderknecht, A., April 2016. Lagostomus maximus (Desmarest) (Rodentia, Chinchillidae), the extant plains vizcacha in the Late Pleistocene of Uruguay. Alcheringa 40, xxx–xxx. ISSN 0311-5518

The extant plains vizcacha, Lagostomus maximus, is described from the Late Pleistocene (Dolores Formation) of Uruguay based on an almost complete articulated skeleton. It is compared with the nominally extinct Pleistocene species of the genus. An AMS 14C taxon-age is determined for L. maximus at 11 879 ± 95 years BP (cal. BP 13 898–13 941). Lagostomus maximus is absent from modern mammal communities in Uruguay, and no Holocene evidence is available. Because L. maximus exhibits remarkable sexual and ontogenetic dimorphism, we examined a range of juvenile, sub-adult and adult male and female specimens. It is not possible to differentiate the articulated Pleistocene fossil from sub-adult specimens of L. maximus based on this sample. Moreover, the skull characteristics, including a broad vertical ramus of the zygomatic arch, semi-circular temporal crest and short robust sagittal crest, most closely resemble extant female individuals. Molar size is non-predictive for ontogenetic stage or body mass because it reaches stability during early adulthood. Other fragmentary skull remains are herein assigned to L. sp. cf. L. maximus. Lagostomus cavifrons from the Pleistocene of Argentina is considered synonymous with L. maximus. Its character states concur with the range of intraspecific variability and it has been established on a young adult or adult male individual. Likewise, the other Argentinean Pleistocene species based on incomplete mandibles, L. angustidens, L. striatus, L. heterogenidens, L. egenus, L. minimus and L. debilis, concur with ontogenetic morphs and are here assigned to Lagostomus sp. The ecological preferences of extant L. maximus infer open arid or semi-arid landscapes for the latest Pleistocene of southern Uruguay. This hypothesis is reinforced by the coeval presence of Microcavia, Galea and small camelids in the same strata. The Last Glacial Maximum likely promoted this environmental setting. Latest Pleistocene or early Holocene climatic change might have facilitated local extinctions and/or range shifts among this mammal fauna.

Martín Ubilla [], Facultad de Ciencias, Universidad de la Republica, Iguá 4225, 11400, Montevideo, Uruguay; Andrés Rinderknecht [], Museo Nacional de Historia Natural, Paleontología, 11000, Montevideo, Uruguay.  相似文献   

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