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1.
The fossil record suggests that modern human morphology evolved in Africa between 150,000 and 50,000 years ago, when the sole inhabitants of Eurasia were the Neanderthals and other equally nonmodern people. However, the earliest modern or near-modern Africans were behaviorally (archaeologically) indistinguishable from their nonmodern, Eurasian contemporaries, and it was only around 50,000-40,000 years ago that a major behavioral difference developed. Archaeological indications of this difference include the oldest indisputable ornaments (or art broadly understood); the oldest evidence for routine use of bone, ivory, and shell to produce formal (standardized) artifacts; greatly accelerated variation in stone artifact assemblages through time and space; and hunting-gathering innovations that promoted significantly larger populations. As a complex, the novel traits imply fully modern cognitive and communicative abilities, or more succinctly, the fully modern capacity for Culture. The competitive advantage of this capacity is obvious, and preliminary dates suggest that it appeared in Africa about 50,000 years ago and then successively in western Asia, eastern Europe, and western Europe, in keeping with an African origin. Arguably, the development of modern behavior depended on a neural change broadly like those that accompanied yet earlier archaeologically detectable behavioral advances. This explanation is problematic, however, because the putative change was in brain organization, not size, and fossil skulls provide little or no secure evidence for brain structure. Other potential objections to a neural advance in Africa 50,000-40,000 years ago or to the wider Out-of-Africa hypothesis, include archaeological evidence (1) that some Neanderthals were actually capable of fully modern behavior and (2) that some Africans were behaviorally modern more than 90,000 years ago.  相似文献   
2.
When Bolivian and Paraguayan leaders entered into war over the contested Chaco Boreal in 1932, they unleashed powerful, violent forces that would dramatically alter history. Understanding the Chaco War as the most pivotal event in Bolivia’s modern history, this article seeks to clarify the modernisation programme that had been underway in Bolivia during the 1920s. Reforms marked the decade and intersected with and accentuated a tense political environment. The political dynamic of the years prior to the outbreak of war showed how fragile the Bolivian system was and how the global economy further eroded the government’s manoeuvrability to avoid war.  相似文献   
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This article shows that, in the study of immigrant integration policy in the U.S. states, it is critical to report data and coding decisions for individual laws. This analysis uses an updated and public database of law‐level decisions, which includes 2,703 legislative actions recorded by the National Conference of State Legislatures from 2005 to 2016. These data are used to estimate models of aggregate state policy activity in a variety of ways: as a single continuum of policy balance versus separate models of welcoming and hostile, lumping all policy subareas together versus analyzing a specific subarea, and lumping all years together in one cross section versus panel analysis. The results in these models differ enough to indicate that reporting codes for individual‐level laws is absolutely essential so that each researcher easily can construct the measure that fits his or her theoretical framework best.  相似文献   
5.
Neuron, a Greek term with a rustic background, made much of its way to its current significance since antiquity, when full recognition was achieved that sensory and motor signals travel through the animal body along nerves (neura, plural). Drawing from classic and recent historical scholarship, this study identifies the successive steps toward such a major breakthrough, starting from the usage of the expression in archaic times and continuing up to the much later transference of a mature theory into the modern world. It is shown that four main consecutive stages may be distinguished in the process: (a) incorporation of the word into early anatomical terminology; (b) theorizing on material composition, origin, properties, and role of the neura in animal bodies; (c) functional association of the neura with a transmitting vehicle; (d) identification of true anatomical and physiological correspondences. Upon this over 2000-year-old foundation is still being built one of the most relevant and fascinating scientific adventures of all time.  相似文献   
6.
In the Middle Ages walls and ditches were used for defensive purposes on land; city walls and moats surrounding castles are part and parcel of the public image of the Middle Ages. Less well known are the defence systems constructed under the sea to protect harbours and waterways. In Scandinavia such systems, ship‐blockages, are especially well investigated in Denmark. In Norway medieval harbour‐defence systems and ship‐blockages are less known. This paper presents and discusses medieval harbours and defence systems in Norway, in particular the newly discovered jetty and possible ship‐blockage on Veøy in Romsdal, western Norway.  相似文献   
7.
Studies of political attention often focus on attention to a single issue, such as front‐page coverage of the economy. However, examining attention to a single issue without accounting for the agenda as a whole can lead to faulty assumptions. One solution is to consider the diversity of attention; that is, how narrowly or widely attention is distributed across items (e.g., issues on an agenda or, at a lower level, frames in an issue debate). Attention diversity is an important variable in its own right, offering insight into how agendas vary in their accessibility to policy problems and perspectives. Yet despite the importance of attention diversity, we lack a standard for how best to measure it. This paper focuses on the four most commonly used measures: the inverse Herfindahl Index, Shannon's H, and their normalized versions. We discuss the purposes of these measures and compare them through simulations and using three real‐world datasets. We conclude that both Shannon's H and its normalized form are better measures, minimizing the danger of spurious findings that could result from the less sensitive Herfindahl measures. The choice between the Shannon's H measures should be made based on whether variance in the total number of possible items (e.g., issues) is meaningful.  相似文献   
8.
Abstract

When Simon McBurney set out to create a play about the fabled relationship between Cambridge mathematician G. H. Hardy and the self-taught Indian genius Srinivasa Ramanujan, he was immediately confronted by the question of how to engage the mathematics authentically. Undaunted by his own uneasiness with the subject, McBurney incorporated a host of experts into the rehearsal process, calling on mathematical educators, expositors, and Fields medalists to come work with the company. While on the surface maths and drama make an incongruous pair, the result was a vibrant collaboration. The final product — the award-winning play A Disappearing Number — shines an interesting light on the surprising similarity between the creative process in mathematics and the creative process in theatre, especially as manifested by the company at Complicite.  相似文献   
9.
马士是西方公认的汉学先驱之一。在中国海关任职长达30余年的时间里,撰写了一系列有关中国问题的著作,它们对20世纪前半期西方的中国历史学著作产生了深刻的影响。他的许多有关中国近代对外关系的著作,不仅开启了国外中国近代史研究的先声,为国外中国近代史研究奠定了坚实的基础,而且拓宽了西方汉学的研究领域,对西方现代汉学的发展起了重要的推逐作用。  相似文献   
10.
For the past two decades, issues of English national identity have provided a fertile field for historical investigation. In the late Victorian era, the development of professional standards of scholarship within the academy gave a new dimension to historical debates. The bitter quarrels about appropriate research techniques from the 1860s to the 1890s, among James Anthony Froude, Edward Freeman and John Horace Round, acted as a proxy for the vision of national identity that each historian espoused. After 1870, the development of a national narrative focused on constitutional history as its primary vehicle. The battle over historical reconstruction represented a surrogate for divergent views about political values and national identity. What sometimes seemed frivolous scholarly skirmishes, therefore, had a much greater political importance. As a result, the long feud had greater importance than the eccentric personalities of the participants appeared to indicate. For Froude, the Tudor age of discovery and religious reformation represented the best of English character. For Freeman, a strong Gladstonian Liberal, consensus and continuity over many centuries defined English history best. John Horace Round, a Conservative stalwart, thought that Freeman had slanted his historical conclusions to validate his Liberal politics and reinterpreted the Norman conquest to express his own political beliefs. Thus the quibbles about shield walls and other issues provided a terrain for the real cause of antagonism: different views of national identity that history furnished. Each historian constructed a usable past in order to justify contemporary discussions of national identity.  相似文献   
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