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1.
While economic literature inspired by the “tragedy of the commons” has emphasised people’s tendency to increase fishing effort beyond desirable levels, sociologists and anthropologists who have studied the social aspects of fishing have often emphasised the capacity of these factors to restrict fishing effort. The article addresses the influence of social norms and communication on fishing effort in an empirical study of the Atlantic blue whiting fishery. The data were generated at a time when this fishery had yet to see efficient quota regulations, and had been subject to a rapid growth in fishing effort, making it the largest fishery in the Atlantic. The article argues that social norms and communication patterns in the fishing fleet create a synergic effect of co-operation and competition on fishing effort. The article questions the view that social norms and communication necessarily represent a solution to the tragedy of the commons.
Stig S. GezeliusEmail:
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2.
Recent discussions of local knowledge emphasize its dynamic nature invoking local peoples’ ability to effectively integrate traditional or local with science-based or “modern” knowledges. The smallholder timber industry of the Amazon’s estuarine floodplain provides an outstanding example of local patterns of resource management and economic activities transformed from within by smallholder farmers who participated in the industrial timber boom of the 1970s and 1980s. These farmers of eastern Amazonia have developed a vertically integrated local industry based on expertise reflecting profound locally developed knowledge of specific forests and management of ecological processes, individual observation and experimentation, as well as concepts and practices derived from temporary employment by large-scale industrial timber firms. At each stage of the smallholder forestry process—from managing natural regeneration to running small sawmills and marketing lumber—local managers apply an innovative set of practices reflecting their diverse experiences. This combination of technical, market, and ecological knowledge results in forests, timber markets, and economic patterns that do not correspond to many of the widely-held generalizations concerning either local or industrial tropical timber exploitation. This article uses data from 7 years of research in the Amazon floodplain.
Christine PadochEmail:
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3.
According to Pigliucci and Kaplan, there is a revolution underway in how we understand fitness landscapes. Recent models suggest that a perennial problem in these landscapes—how to get from one peak across a fitness valley to another peak—is, in fact, non-existent. In this paper I assess the structure and the extent of Pigliucci and Kaplan’s proposed revolution and argue for two points. First, I provide an alternative interpretation of what underwrites this revolution, motivated by some recent work on model-based science. Second, I show that the implications of this revolution need to carefully assessed depending on question being asked, for peak-shifting is not central to all evolutionary questions that fitness landscapes have been used to explore.
Brett CalcottEmail:
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4.
5.
It is generally assumed that peasants optimize security of food supply rather than maximize profit. One way of securing the survival of the household is to spread risk in farming by extending the planting and harvesting seasons in order to avoid all crops being damaged if unfavorable production conditions should occur. It thus seems peculiar that some Himalayan peasant communities act in the opposite manner by compressing peak agricultural activity into a minimum period, and furthermore that all cultivators simultaneously start planting and harvesting on dates fixed by the village headman in consultation with a lama (Buddhist priest). Rather than suggesting that any single explanation for this practice is the right one, however, this article contends that specific farming system cannot be understood properly unless a combination of subsystems — or facets — are included in the analyses.
Ole R. Vetaas (Corresponding author)Email:
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6.
This paper demonstrates that the human visual system, the primary sensory conduit for primates, processes ambient energy in a way that obligatorily constructs the objects that we ineluctably perceive. And since our perceptual apparatus processes information only in terms of objects (along with the properties and movements of objects), we are limited in our ability to comprehend ‘what is’ when we move beyond our ordinary world of midsize objects—as, for example, when we address the micro microworld of quantum physics.
Philip Richard SullivanEmail:
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7.
T. Ryan Gregory 《Evolution》2008,1(3):259-273
The occurrence, generality, and causes of large-scale evolutionary trends—directional changes over long periods of time—have been the subject of intensive study and debate in evolutionary science. Large-scale patterns in the history of life have also been of considerable interest to nonspecialists, although misinterpretations and misunderstandings of this important issue are common and can have significant implications for an overall understanding of evolution. This paper provides an overview of how trends are identified, categorized, and explained in evolutionary biology. Rather than reviewing any particular trend in detail, the intent is to provide a framework for understanding large-scale evolutionary patterns in general and to highlight the fact that both the patterns and their underlying causes are usually quite complex.
T. Ryan GregoryEmail:
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8.
Recent advances in hardware and software virtualization offer unprecedented management capabilities for the mapping of virtual resources to physical resources. It is highly desirable to further create a “service hosting abstraction” that allows application owners to focus on service level objectives (SLOs) for their applications. This calls for a resource management solution that achieves the SLOs for many applications in response to changing data center conditions and hides the complexity from both application owners and data center operators. In this paper, we describe an automated capacity and workload management system that integrates multiple resource controllers at three different scopes and time scales. Simulation and experimental results confirm that such an integrated solution ensures efficient and effective use of data center resources while reducing service level violations for high priority applications.
Ludmila CherkasovaEmail:
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9.
T. Ryan Gregory 《Evolution》2008,1(2):121-137
Charles Darwin sketched his first evolutionary tree in 1837, and trees have remained a central metaphor in evolutionary biology up to the present. Today, phylogenetics—the science of constructing and evaluating hypotheses about historical patterns of descent in the form of evolutionary trees—has become pervasive within and increasingly outside evolutionary biology. Fostering skills in “tree thinking” is therefore a critical component of biological education. Conversely, misconceptions about evolutionary trees can be very detrimental to one’s understanding of the patterns and processes that have occurred in the history of life. This paper provides a basic introduction to evolutionary trees, including some guidelines for how and how not to read them. Ten of the most common misconceptions about evolutionary trees and their implications for understanding evolution are addressed.
T. Ryan GregoryEmail:
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10.
The Cauchy problem for one-dimensional spiking neuron models   总被引:1,自引:1,他引:0  
I consider spiking neuron models defined by a one-dimensional differential equation and a reset—i.e., neuron models of the integrate-and-fire type. I address the question of the existence and uniqueness of a solution on for a given initial condition. It turns out that the reset introduces a countable and ordered set of backward solutions for a given initial condition. I discuss the implications of these mathematical results in terms of neural coding and spike timing precision.
Romain BretteEmail:
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11.
This paper attempts some predictions about the social consequences of nanotechnology and the ethical issues they raise. I set out four features of nanotechnology that are likely to be important in determining its impact and argue that nanotechnology will have significant social impacts in—at least—the areas of health and medicine, the balance of power between citizens and governments, and the balance of power between citizens and corporations. More importantly, responding to the challenge of nanotechnology will require confronting “philosophical” questions about the sort of society we wish to create and the role that technology might play in creating it. This in turn will require developing institutions and processes that allow the public to wield real power in relation to technological trajectories. My ultimate contention is that the immediate task established by the likely social impacts of nanotechnology is not so much to develop an ethics of nanotechnology as to facilitate an ethical conversation about nanotechnology.
Robert SparrowEmail:
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12.
Despite the attention given to social relations in the pastoral literature, the role of livestock acquisitions—additions of livestock to herds through bridewealth, exchanges, gifts, payments, and begging (requests)—in herd build up has usually been assumed to be relatively minor compared to births and relevant mostly when the need for rebuilding arises after major losses. This study is based on an unusual set of data—the reproductive histories of the female cattle, camels, and goats and sheep of 13 Ngisonyoka Turkana nomadic herders in northwestern Kenya, collected in 1987. The article reports on the means by which mothers were added to the herd and how these changed through time. The results suggest that for this population in the late 1970s and 1980s, acquisitions were not merely relevant when disaster struck, but instead were a continuously important component of herd management. The results demonstrate the crucial role of social networks in the survival of Ngisonyoka pastoralists in their non-equilibrial ecosystem. Social exchanges, such as bridewealth, provide a resource security well suited to the challenges of coping with such unpredictable environments. Researchers and policymakers are urged to make efforts to support such indigenous networks if they want nomadic pastoralists to continue their effective use of arid, marginal lands.
J. Terrence McCabeEmail:
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13.
This article argues against the idea that indigenous cultural change and knowledge loss are inevitably bonded to one another, with particular reference to agro-productive transformations. This view has not only ignored the potential of these productive systems—well documented in recent decades—but has often threatened them by promoting development policies based on mistaken premises. It is suggested here that some indigenous peoples’ productive responses to market integration may in fact offer alternatives to the paradoxes of development in seemingly fragile tropical environments. This article reports, in particular, on the strategies developed by the Piaroa, from southern Venezuela. Contemporary large and permanent Piaroa communities, which resulted from their involvement in aspects of national society, have been able to sustain the forests on which they depend while satisfying their food and market necessities. This has been possible due to a series of market strategies based on their agroforestal tradition, which have emphasised the commercialization of secondary forest products. The article proposes that these strategies have been underestimated due to the market conditions in which Piaroa farmers are immersed, and from which they have learnt the very principles of “capitalism.” Oil dependent and saturated with corruption, the Venezuelan market hampers their full economic integration, contributing to the idea that their agroforestry system can only produce at subsistence levels.
Germán N. FreireEmail:
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14.
Jablonka and Lamb's claim that evolutionary biology is undergoing a ‘revolution’ is queried. But the very concept of revolutionary change has uncertain application to a field organized in the manner of contemporary biology. The explanatory primacy of sequence properties is also discussed.
Peter Godfrey-SmithEmail:
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15.
Several hypotheses on the form and function of sex differences in social behaviors were tested. The results suggest that friendship preferences in both sexes can be understood in terms of perceived reciprocity potential—capacity and willingness to engage in a mutually beneficial relationship. Divergent social styles may in turn reflect trade-offs between behaviors selected to maintain large, functional coalitions in men and intimate, secure relationships in women. The findings are interpreted from a broad socio-relational framework of the types of behaviors that facilitate selective advertisement and investment of reciprocity potential across individuals and within groups of men and women.
Jacob M. VigilEmail:
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16.
We construct a mapping from complex recursive linguistic data structures to spherical wave functions using Smolensky’s filler/role bindings and tensor product representations. Syntactic language processing is then described by the transient evolution of these spherical patterns whose amplitudes are governed by nonlinear order parameter equations. Implications of the model in terms of brain wave dynamics are indicated. Electronic supplementary material  The online version of this article (doi: ) contains supplementary material, which is available to authorized users.
Peter beim GrabenEmail:
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17.
This article contributes to the encouraging recent trend toward more critical examination of the linkages between remote sensing and social analysis of environmental change. Using two case studies from Malawi, we explain the importance of thinking about temporal scale when using remote sensing data. Specifically, from our on-the-ground research, we came to appreciate three important issues: (1) multiple causation and multiple temporal scales operating simultaneously—making inference of casual relations between particular social factors and observed land use changes difficult; (2) ‘visible’ vs. ‘invisible’ processes and events; and (3) ‘continuous’ vs. ‘punctuated’ social and environmental processes. We observe that in each case, social differentiation is key to understanding which temporal frames are most relevant in understanding observed land use dynamics. We conclude that, while these are not entirely new observations, research on the applications of remote sensing in social analysis of environmental change could be enriched by more rigorous examination of linkages between environmental change, temporal scale, and the social relations (including social differentiation) that can help to explain how and why particular temporal frames are most salient.
Pauline E. PetersEmail:
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18.
Temporal Heterogeneity in the Study of African Land Use   总被引:1,自引:0,他引:1  
This paper introduces a set of four collaborative papers exploring temporal heterogeneity in the analysis of African land use over a decadal time period, from 10 to 50 years, in the second half of the twentieth century. The four cases were chosen amongst the seven teams of anthropologists, human geographers and remote sensing specialists who had carried out long-term research and who met to discuss their findings at a workshop in 2003. All seven teams’ work and the collective discussion—on Casamance (Senegal), Brong Ahafo (Ghana), Southern Niger/Northern Cote d’Ivoire, Oyo State (Nigeria), Maasai Mara (Kenya and Tanzania), Gwembe (Zambia), and Malawi—inform this introduction. We identify several temporal processes in all the cases, each operating on its own temporal frame: population growth and, above all, mobility; livelihood change through crop and occupational change; tenure ambiguity; powerful though “punctuated” interventions by state policy; and climate change. Conceptual and methodological implications are disussed.
John UnruhEmail:
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19.
This paper is an interpretation and defense of Richard Levins’ “The Strategy of Model Building in Population Biology,” which has been extremely influential among biologists since its publication 40 years ago. In this article, Levins confronted some of the deepest philosophical issues surrounding modeling and theory construction. By way of interpretation, I discuss each of Levins’ major philosophical themes: the problem of complexity, the brute-force approach, the existence and consequence of tradeoffs, and robustness analysis. I argue that Levins’ article is concerned, at its core, with justifying the use of multiple, idealized models in population biology.
Michael WeisbergEmail:
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20.
Large-scale—even genome-wide—duplications have repeatedly been invoked as an explanation for major radiations. Teleosts, the most species-rich vertebrate clade, underwent a “fish-specific genome duplication” (FSGD) that is shared by most ray-finned fish lineages. We investigate here the Hox complement of the goldeye (Hiodon alosoides), a representative of Osteoglossomorpha, the most basal teleostean clade. An extensive PCR survey reveals that goldeye has at least eight Hox clusters, indicating a duplicated genome compared to basal actinopterygians. The possession of duplicated Hox clusters is uncoupled to species richness. The Hox system of the goldeye is substantially different from that of other teleost lineages, having retained several duplicates of Hox genes for which crown teleosts have lost at least one copy. A detailed analysis of the PCR fragments as well as full length sequences of two HoxA13 paralogs, and HoxA10 and HoxC4 genes places the duplication event close in time to the divergence of Osteoglossomorpha and crown teleosts. The data are consistent with—but do not conclusively prove—that Osteoglossomorpha shares the FSGD. Electronic supplementary material  The online version of this article (doi:) contains supplementary material, which is available to authorized users.
Chi-hua ChiuEmail:
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