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101.
Several evolutionary mechanisms have been proposed to explain how natural selection leads to cooperation between competing individuals. Social dilemmas modelled with the aid of game theory capture the essence of this problem, and computer simulation is usually the technique used to test and formalise those explanatory mechanisms. However, scarce attention has been paid to what the notion of ‘mechanisms’ means and involves in the literature. Also, the key issue about when a computer simulation provides a good explanation tends to be ignored. In this article, we tackle these two drawbacks in the literature by calling attention to the implications of the notion of ‘social mechanism’ along different conceptual dimensions, such as ontological status, regularity, transparency, intelligibility, and reduction. We also claim that computer simulation, and specially agent-based modelling, provides a plausible explanation to social cooperation only if it satisfies some criteria of empirical adequacy instead of just being capable of generating cooperation in a virtual system. Finally, we relate these issues to five evolutionary mechanisms that explain the evolution of cooperation. We review and briefly describe the literature on these mechanisms, and we explain their most important features, how they are to be considered along the conceptual dimensions used to describe the notion of mechanism, what is the empirical and computational evidence to support them, and which are the shortcomings that each of them has as explanatory hypotheses for the evolution of cooperation.  相似文献   
102.
Long-distance commuting (LDC) is an increasingly relevant strategy of labor mobility worldwide and is therefore key to understanding the structure and dynamics of labor markets. However, little is known about the effect that LDC has on the labor market equilibrium of host territories. This paper addresses this gap for the case of Chile. While LDC is a useful strategy for improving salary and employment on a national scale, our results show a negative effect for residents in host territories (on a local scale), particularly when LDC results in commuters with similar characteristics to residents competing for the same jobs.  相似文献   
103.
History shows that wars can be enormously disruptive of economic activity, especially international trade, national income, and global economic welfare. This article analyzes the impact on the European regions the Russian invasion of Ukraine using the largest and most updated multiregional input-output model for Europe. Two shocks, trade and inflation, and four alternative scenarios are simulated. The scenarios are considered regarding the number of countries applying a trade embargo, the exemption of oil and gas, and the potential trade diversions with third countries such as China. We obtained a significant fall in GDP (−1.7%), 3.7 m lost jobs and 3% raise over the prewar inflation rate. For trade shock, large indirect effects are obtained, indicating the high relevance of the sectors and countries exposed to the war and the sanctions. The republics of the former Soviet Union, as well as the satellite countries of the former communism, face the harshest adverse impacts. This work shows the importance of breaking Russia's colonial economic ties to the countries in Eastern Europe.  相似文献   
104.
ABSTRACT

This article examines the royal acclamation ceremonies of the Portuguese crown in order to grasp the responsiveness of the institution of the monarchy and regime to the challenges of modernity throughout the delicate watershed period of the late eighteenth and nineteenth centuries. The Portuguese Catholic and absolutist monarchy of the ancien régime had a strict protocol and a set of insignia of power that acted together at the moment of the acclamation and legitimation of each new king. The purpose of this research is to assess the adaptation and reinvention of these insignia and rituals according to the revolutionary demands of social change and secularization brought about by the turbulent period of the beginning of the nineteenth century: the French military invasions (1807–11); the departure of the royal family, court and administration to Brazil (1807); the liberal constitutional revolution (1820); and the civil war pitting liberals against absolutists (1832–34). The new constitutional monarchy that came out of this revolutionary flow faced many challenges of legitimacy, including the test of its capacity to create a modern royal imaginary updated to the cultural mindset of national and secular societies, and capable of bonding rulers with their people. The authors believe that the study of the acclamation ceremonies in the Portuguese constitutional monarchy can give us an accurate perspective on the quality of the symbolic image of the crown, therefore assessing the political efficiency of rituals as one of the structural aspects for institutional legitimization.  相似文献   
105.
SUMMARY: The aim of this paper is to determine the degree of standardization of pottery production and the units of measure that regulated their production. The group chosen to test this methodology is known as the Spanish olive jar. It is a series of productions manufactured in the south of the Iberian Peninsula throughout the Early Modern Period. The methodology begins with the morphometric characterisation of each vessel around a series of quantitative variables. Then, the Test for Normality is performed, and the Product-Moment Correlation Coefficient is calculated. Subsequently, a Cluster Analysis identifies different groups of Spanish olive jars. The Principal Component Analysis provides additional information that allows for a deeper understanding of the groups obtained. As a final step, calculating the Coefficient of Variation allows us to know the degree of standardization of each variable. Finally, once all these data are known, the possible units of measure that governed the production system of the Spanish olive jar can be recognized.  相似文献   
106.
ABSTRACT

This paper presents the results of the analyses of 3793 bird remains archaeologically recovered from seven late pre-Hispanic sites (~AD 1000–1500) on islands of the Venezuelan Caribbean. In order to address subsistence and manufacturing uses of bird bones, we first discuss the recovery process of this unique sample. We proceed to investigate the bones' archaeological contexts as well as the taphonomy in play and analyze diverse bone categories. We found that indigenous peoples consistently targeted several families of birds for food or feathers or both, and that avian bones were used for fashioning tools and adornments. We also discuss possible signatures of island campsite seasonal occupancy as inferred from the bio-ecology of the identified bird taxa. The data suggest that the differentiation of nesting grounds between the Red-footed and Brown Booby in the Southeastern Caribbean may be a result of anthropogenically-induced adaptation. The findings discussed in this paper open challenging avenues for assessing long-term changes in bird communities including the dynamics of resident and wintering bird populations.  相似文献   
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109.
Hominin presence is well documented in a number of Early Pleistocene and early Middle Pleistocene European localities. However, the evidence currently available indicates that Acheulean handaxes spread in the fluvial basins of Western Europe during MIS 11, ~400 kyr ago, associated with Homo heidelbergensis, although a number of early Middle Pleistocene Acheulean assemblages have been dated from MIS 16 onwards. For this reason, the magnetostratigraphic dating in Southeast Spain of two archaeological localities, the open-air site of Solana del Zamborino (SZ) and the rock-shelter site of Cueva Negra del Estrecho del Quípar (EQ), that put back the appearance of handaxes to the Early-Middle Pleistocene limit (Scott and Gibert, 2009) is of particular interest, as the new ages suggest that H. heidelbergensis was a contemporary of H. antecessor that had the ability to produce Levallois debitage and to control fire during the Early-Middle Pleistocene transition. However, we have detected a number of errors in the interpretation of the archaeological assemblage from the first site as well as striking discrepancies with the original faunal lists published for both localities, with several large mammal species that are omitted or arbitrarily changed to make the assemblages consistent with the new ages deduced from magnetostratigraphy. For this reason, we suggest that: (1) the finding of reverse polarity in the sediments sampled for paleomagnetism in SZ may simply record one of the polarity reversals that took place during the Brunhes Chron, although the use by Scott and Gibert (2009) of a composite stratigraphic column precludes correlating these levels with a specific reversal; and (2) the fauna and tools of EQ correspond to the late Middle Pleistocene sedimentary infillings of this karst site, while the samples taken for paleomagnetism belong to a previous sedimentary cycle during the Matuyama Chron. Such interpretations would be in better agreement with the age estimates provided by biostratigraphy and also with the currently accepted chronology for the appearance of Acheulean industries in Western Europe.  相似文献   
110.
A large sample of human bones from a series of archaeological sites in the south‐eastern Iberian Peninsula was selected for δ13C and δ15N stable isotope analysis. Except for some contrast samples, the remains date from the first half of the second millennium cal BC and are ascribed to the Argar Culture, which developed during the Bronze Age in south‐eastern Iberia. Most authors have considered that this region reached a high degree of social hierarchical organization at this time, as demonstrated by the funerary record, both with regard to the grave goods and to the evidence of physical effort and diseases on the human remains. Results of the isotope analysis revealed the existence of differences among the settlements studied, as well as differences over time within every settlement and among the various individuals tested. Some variances can be assigned to social classes/status and others are linked to chronological factors. In particular, changes in δ13C can be explained by the increasing aridity of the first half of the second millennium cal BC, although other causes can be put forward too.  相似文献   
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