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101.
There is limited available data on the environmental context of the arrival of the first anatomically modern humans (AMH) in North Africa, and subsequent Paleolithic and Neolithic occupations within this region. Microvertebrates such as rodents, shrews, amphibians, and squamates are known to be good indicators of climate and landscape changes. They also represent continental paleoecological records that can be directly related to human occupations. Moreover, faunas and humans have been subjected to several dispersal waves through similar routes, and some rodents may present anthropophilous behavior. Therefore, by understanding the dispersal pattern and pathways of these microvertebrates, it is possible to propose scenarios for human dispersal events. In this study we took the rich microfaunal assemblages from the Témara region, Atlantic Morocco (El Harhoura 2 and El Mnasra Caves), and placed them within a broader synthesis, in order to highlight the role of microvertebrates in providing a better understanding of the human-environment relationship during the Late Quaternary in North Africa.  相似文献   
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The Rabat-Témara region of the Moroccan Atlantic coast reveals a succession of Quaternary palaeobeaches. This coastal area is dotted with numerous prehistoric caves. The study of the Upper Pleistocene coastal landscape associated with these caves is of paramount importance in the knowledge of human population subsistence. During the Upper Pleistocene, the ocean level changes drastically influenced the coastal geomorphology as well as the fauna assemblages. The chrono-lithostratographical analysis of the coastal sedimentary formations allows the distinction of three sequences rich in marine fauna. These sequences date from MIS 11 to MIS 5. The identification of malacofauna species from these deposits revealed 39 species, along with Bryozoans, Crustaceans, and Echinoids. These assemblages show a constant fauna cortege highlighted by the dominance of the amphi-Atlantic species Stramonita haemastoma. This species shows an increase in the number of specimens in the uppermost part of marine deposits, probably in relation with a climate warming in the MIS 5. This fauna of both intertidal rocky substrates and sandy substratum indicates environmental conditions close to the present-day Rabat-Témara coastline. As in other coastal locations of Africa from MIS 5, the Middle Stone Age Homo sapiens population benefitted from a littoral environment rich in coastal resources. Comparison between thanatocenoses and archaeological records allows us to identify both species available for Middle Stone Age population and those preferred for human use.  相似文献   
103.
As the sobriquet «Zweistein» suggests, within the theoretical physics community Wolfgang Pauli came to be regarded as second in eminence only to Albert Einstein. Over a period of thirty-five years, they interacted both intellectually and personally. This paper focuses on four interrelated topics of their discussions. 1) The theory of relativity: at the age of twenty, Pauli prepared the definitive survey of relativity, a survey which he revised near the end of his life and which remains invaluable to physicists and historians of physics. 2) Unified field theories: although initially sympathetic to Einstein's search for a unified theory of electromagnetism and gravitation, and having made important contributions to the subject, Pauli came to regard such efforts as fruitless. 3) Foundations of quantum mechanics: Pauli's negative evaluation of Einstein's program grew out of their sharply differing evaluations of the role that quantum mechanics would play in the future, development of theoretical physics. 4) Quantum gravity: Pauli recognized that, until the achievement of a successful reconciliation of quantum mechanics and general relativity — an achievement that still eludes us — Einstein's challenge to quantum mechanics could not be laid to rest.  相似文献   
104.
ABSTRACT Most “wage curve” studies ignore the geography of local labor markets. However, when a local labor market is in close proximity of other labor markets, a local shock that increases unemployment may not lead to lower pay rates if employers fear outward migration of their workers. Hence, the unemployment elasticity of pay will be greater, the more isolated the local labor market is. Wages are also expected to be higher in regions that interact strongly with other regions. These hypotheses are confirmed by means of an estimation of wage curves with data for 327 regions of western Germany over the period 1990–1997.  相似文献   
105.
ABSTRACT We investigate how cross‐country differences in firms' fixed set‐up costs affect the trade‐off between global efficiency and spatial equity. Our analysis reveals that the standard assumption of symmetry in set‐up costs masks the existence of an interesting effect: the range of available varieties depends on the spatial distribution of firms. In such a setting, where the market outcome leads to excessive agglomeration in the symmetric case, a planner may opt for asymmetric set‐up costs and even more agglomeration. We show that the planner will always favor lower set‐up costs in the large country with more agglomeration when the consumer's marginal preference for variety is high, or with less agglomeration when the consumer's marginal preference for variety is low.  相似文献   
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In the 1970s and 1980s, regional analysis was an influential part of archaeological research, providing a discrete set of geographical tools inspired by a processual epistemological and interpretive perspective. With the advent of new technologies, new methods, and new paradigms, archaeological research on regional space has undergone significant changes. This article reviews the state of regional archaeology, beginning with a consideration of its history and a discussion of the fundamental issues facing regional investigations before focusing on developments over the last several years. On one hand, the diversification of archaeological theory has created new paradigms for thinking about human relationships with one another and with the physical environment across regional space; in this regard, historical ecology, landscape archaeology, and evolutionary theory have been particularly influential in recent years. This has led to a corresponding diversification of the traditional methods of regional analysis. Most notably, the advent of powerful digital technologies has introduced new tools, especially those from the geographic information sciences, that build on the quantitative methods of past approaches. The investigation of regional data is no longer based on a discrete toolkit of simple mathematical and graphical procedures for representing spatial relationships. Instead, regional archaeology has matured into a diversity of multiscalar spatial and geostatistical techniques that inform many areas of archaeological inquiry.  相似文献   
109.
This article focuses on the presence of humans in Siberia and the Russian Far East at the coldest time of the Late Pleistocene, called the Last Glacial Maximum (LGM) and dated to c. 20,000–18,000 rcbp. Reconstruction of the LGM environment of Siberia, based on the latest models and compilations, provides a background for human existence in this region. Most of Siberia and the Russian Far East at c. 20,000–18,000 rcbp was covered by tundra and cool steppe, with some forest formations in the river valleys. Climate was much colder and drier than it is today. Eighteen Upper Paleolithic sites in Siberia are radiocarbon dated strictly to the LGM, and at least six of them, located in southern parts of western and eastern Siberia and the Russian Far East, have solid evidence of occupation during that time span. It seems clear that southern Siberia was populated by humans even at the height of the LGM, and that there was no dramatic decline or complete disappearance of humans in Siberia at that time. The degree of human adaptation to periglacial landscapes in the mid-Upper Paleolithic of northern Eurasia was quite high; humans coped with the cold and dry environmental conditions using microblade technology, artificial shelters, tailored clothes, and megafaunal bones as fuel. An erratum to this article can be found at  相似文献   
110.
During the Late Intermediate period (LIP, c. A.D. 1000–1400), the central Andes experienced the decline of the Wari and Tiwanaku states, as well as processes of state formation, regional population growth, and competition culminating in the imperial expansion of the Chimú and Inka polities. The LIP holds the potential to link the archaeological features of early Andean states with the material signatures of the later ones, providing a critical means of contextualizing the intergenerational continuities and breaks in state structures and imperial strategies. The recent proliferation of LIP research and the completion of a number of regional studies permit the overview of six LIP regions and the comparison of highland and lowland patterns of political and economic organization, social complexity, and group identity.  相似文献   
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