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1.
Biogeographical studies in Amazonia have commonly taken a historical, rather than an ecological approach. General patterns have been sought in the distribution maps of different species, and these have been explained in terms of past or present distribution barriers, especially past climates and large rivers. Implicitly, and often also explicitly, it is assumed that Amazonia is ecologically so uniform that present-day ecological conditions are rather insignificant in determining species distribution patterns and speciation. However, this assumption is more based on the lack of relevant data than on actual observations of environmental uniformity or ecological unspecialization of the species. Recent studies have indeed documented ecological heterogeneity and floristic differences among sites that were previously thought similar. In the absence of direct knowledge of the past, more complete ecological and environmental understanding of the present-day Amazonia are needed for evaluating the relative roles of historical and ecological factors in Amazonian biogeography and biodiversity.  相似文献   

2.
Landscape genetics is an emerging discipline that utilizes environmental and historical data to understand geographic patterns of genetic diversity. Niche modelling has added a new dimension to such efforts by allowing species–environmental associations to be projected into the past so that hypotheses about historical vicariance can be generated and tested independently with genetic data. However, previous approaches have primarily utilized DNA sequence data to test inferences about historical isolation and may have missed very recent episodes of environmentally mediated divergence. We type 15 microsatellite loci in California mule deer and identify five genetic groupings through a Structure analysis that are also well predicted by environmental data. We project the niches of these five deer ecotypes to the last glacial maximum (LGM) and show they overlap to a much greater extent than today, suggesting that vicariance associated with the LGM cannot explain the present-day genetic patterns. Further, we analyse mitochondrial DNA (mtDNA) sequence trees to search for evidence of historical vicariance and find only two well-supported clades. A coalescence-based analysis of mtDNA data shows that the genetic divergence of the mule deer genetic clusters in California is recent and appears to be mediated by ecological factors. The importance of environmental factors in explaining the genetic diversity of California mule deer is unexpected given that they are highly mobile species and have a broad habitat distribution. Geographic differences in the timing of reproduction and peak vegetation as well as habitat choice reflecting natal origin may explain the persistence of genetic subdivision.  相似文献   

3.
Ecological, historical, and evolutionary hypotheses are important to explain geographical diversity gradients in many clades, but few studies have combined them into a single analysis allowing a comparison of their relative importance. This study aimed to evaluate the relative importance of ecological, historical, and evolutionary hypotheses in explaining the current global distribution of non‐marine turtles, a group whose distribution patterns are still poorly explored. We used data from distribution range maps of 336 species of non‐marine turtles, environmental layers, and phylogeny to obtain richness estimates of these animals in 2° × 2° cells and predictors related to ecological, evolutionary and historical hypotheses driving richness patterns. Then we used a path analysis to evaluate direct and indirect effects of the predictors on turtle richness. Ancestral area reconstruction was also performed in order to evaluate the influence of time‐for‐speciation in the current diversity of the group. We found that environmental variables had the highest direct effects on non‐marine turtle richness, whereas diversification rates and area available in the last 55 million yr minimally influenced turtle distributions. We found evidence for the time‐for‐speciation effect, since regions colonized early were generally richer than recently colonized regions. In addition, regions with a high number of colonization events had a higher number of turtle species. Our results suggested that ecological processes may influence non‐marine turtle richness independent of diversification rates, but they are probably related to dispersal abilities. However, colonization time was also an important component that must be taken into account. Finally, our study provided additional support for the importance of ecological (climate and productivity) and historical (time‐for‐speciation and dispersal) processes in shaping current biodiversity patterns.  相似文献   

4.
Humans in many societies cooperate in economic experiments at much higher levels than would be expected if their goal was maximizing economic returns, even when their interactions are anonymous and one-shot. This is a puzzle because paying a cost to benefit another in one-shot interactions gives no direct or indirect benefits to the cooperator. This paper explores the logic of two competing evolutionary hypotheses to explain this behavior. The ``norm psychology'' hypothesis holds that a player's choice of strategy reflects socially-learned cultural norms. Its premise is that over the course of human evolutionary history, cultural norms varied considerably across human societies, and through a process of gene-culture co-evolution, humans evolved mechanisms to learn and adopt the norms that are successful in their particular society. The ``mismatch'' hypothesis holds that pro-social preferences evolved genetically in our hunter–gatherer past where one-shot anonymous interactions were rare and these preferences are misapplied in modern laboratory settings. I compare these hypotheses by adopting a well-known model of the mismatch hypothesis and show that selection for one-shot cooperation in the model is an artifact of agents being confined to only two strategies: Tit-for-Tat and Always Defect. Allowing for repentant and forgiving strategies reverses selection away from one-shot cooperation under all environmental parameters. Direct reciprocity does not necessarily lead to cooperation, but instead generates many different normative equilibria depending on a group's idiosyncratic evolutionary history. Therefore, an agent whose behavior is evoked solely from non-cultural environmental cues will be disadvantaged relative to an agent who learns the locally successful norms. Cooperation in one-shot laboratory experiments is thus more easily explained as the result of a psychology evolved for learning social norms than as a genetic mismatch.  相似文献   

5.
江苏省区域农业生态经济的时空变异分析   总被引:1,自引:0,他引:1  
唐婷  李超  张雷  吕坤  周治国 《生态学报》2014,34(14):4025-4036
以江苏省徐连、沿海、宁镇扬、沿江和太湖5个经济区及其9个代表县市区域为研究对象,基于"社会-生态-经济"的系统分析,建立了包括目标层、准则层和指标层3个层次多指标的农业生态经济综合评价指标体系,采用主成分分析方法对评价指标体系进行检验、筛选,并以江苏省为案例,综合分析了农业生态经济系统的时空变异特征。结果表明:江苏省农业生态经济发展水平的时空变异明显,空间上,徐连、沿海、宁镇扬、沿江和太湖5个经济区表现出由北向南逐渐上升的趋势,且随时间的推移逐渐上升;时间上,徐连和太湖经济区农业生态经济发展水平在1999—2008年间呈持续上升,处于良好或优质协调状态。虽然两经济区的农业生态环境-经济发展协调发展水平均较高,但差距较大,徐连和太湖经济区的农业生态环境-经济发展协调度从1999年到2008年呈逐渐下降趋势,但总体上仍处于良好或优质协调状态。  相似文献   

6.
A growing body of theoretical and empirical research has examined cultural transmission and adaptive cultural behaviour at the individual, within-group level. However, relatively few studies have tried to examine proximate transmission or test ultimate adaptive hypotheses about behavioural or cultural diversity at a between-societies macro-level. In both the history of anthropology and in present-day work, a common approach to examining adaptive behaviour at the macro-level has been through correlating various cultural traits with features of ecology. We discuss some difficulties with simple ecological associations, and then review cultural phylogenetic studies that have attempted to go beyond correlations to understand the underlying cultural evolutionary processes. We conclude with an example of a phylogenetically controlled approach to understanding proximate transmission pathways in Austronesian cultural diversity.  相似文献   

7.
Globalization, a process characterized by the growing interdependence of the world's people, impacts health systems and the social determinants of health in ways that are detrimental to health equity. In a world in which there are few countervailing normative and policy approaches to the dominant neoliberal regime underpinning globalization, the human rights paradigm constitutes a widely shared foundation for challenging globalization's effects. The substantive rights enumerated in human rights instruments include the right to the highest attainable level of physical and mental health and others that are relevant to the determinants of health. The rights stipulated in these documents impose extensive legal obligations on states that have ratified these documents and confer health entitlements on their residents. Human rights norms have also inspired civil society efforts to improve access to essential medicines and medical services, particularly for HIV/AIDS. Nevertheless, many factors reduce the potential counterweight human rights might exert, including and specifically the nature of the human rights approach, weak political commitments to promoting and protecting health rights on the part of some states and their lack of institutional and economic resources to do so. Global economic markets and the relative power of global economic institutions are also shrinking national policy space. This article reviews the potential contributions and limitations of human rights to achieving greater equity in shaping the social determinants of health.  相似文献   

8.
Origins of Specialized Pastoral Production in East Africa   总被引:1,自引:0,他引:1  
The results of recent archeological research in the Loita-Mara area of Kenya offer new information on the timing and process of the development of pastoralism in East Africa. They suggest that a pattern of specialized pastoral production, similar to that of contemporary East African pastoralists such as the Maasai, was present in parts of East Africa 2,000 years ago. It may have developed as a result of new opportunities for increased pastoral production. A bimodal pattern of rainfall with a short dry season, similar to the modern climatic regime, appeared about 3,000 years ago, which allowed year-round milk production from cattle herds. The development of pastoralism in East Africa preceded agriculture and took place in a social and economic context of relationships between hunter-gatherers and pastoralists. Environmental opportunity, combined with cultural competition, may have provided the impetus toward pastoral specialization.  相似文献   

9.
Human beings persist in an extraordinary range of ecological settings, in the process exhibiting enormous behavioural diversity, both within and between populations. People vary in their social, mating and parental behaviour and have diverse and elaborate beliefs, traditions, norms and institutions. The aim of this theme issue is to ask whether, and how, evolutionary theory can help us to understand this diversity. In this introductory article, we provide a background to the debate surrounding how best to understand behavioural diversity using evolutionary models of human behaviour. In particular, we examine how diversity has been viewed by the main subdisciplines within the human evolutionary behavioural sciences, focusing in particular on the human behavioural ecology, evolutionary psychology and cultural evolution approaches. In addition to differences in focus and methodology, these subdisciplines have traditionally varied in the emphasis placed on human universals, ecological factors and socially learned behaviour, and on how they have addressed the issue of genetic variation. We reaffirm that evolutionary theory provides an essential framework for understanding behavioural diversity within and between human populations, but argue that greater integration between the subfields is critical to developing a satisfactory understanding of diversity.  相似文献   

10.
Numerous hypotheses have been proposed to explain variation in reproductive performance and local recruitment of animals. While most studies have examined the influence of one or a few social and ecological factors on fitness traits, comprehensive analyses jointly testing the relative importance of each of many factors are rare. We investigated how a multitude of environmental and social conditions simultaneously affected reproductive performance and local recruitment of the red-backed shrike Lanius collurio (L.). Specifically, we tested hypotheses relating to timing of breeding, parental quality, nest predation, nest site selection, territory quality, intraspecific density and weather. Using model selection procedures, predictions of each hypothesis were first analysed separately, before a full model was constructed including variables selected in the single-hypothesis tests. From 1988 to 1992, 50% of 332 first clutches produced at least one fledgling, while 38.7% of 111 replacement clutches were successful. Timing of breeding, nest site selection, predation pressure, territory quality and intraspecific density influenced nest success in the single-hypothesis tests. The full model revealed that nest success was negatively associated with laying date, intraspecific density, and year, while nest success increased with nest concealment. Number of fledglings per successful nest was only influenced by nest concealment: better-camouflaged nests produced more fledglings. Probability of local recruitment was related to timing of breeding, parental quality and territory quality in the single-hypothesis tests. The full models confirmed the important role of territory quality for recruitment probability. Our results suggest that reproductive performance, and particularly nest success, of the red-backed shrike is primarily affected by timing of breeding, nest site selection, and intraspecific density. This study highlights the importance of considering many factors at the same time, when trying to evaluate their relative contributions to fitness and life history evolution.Electronic supplementary material Supplementary material is available for this article at  相似文献   

11.
成功  张家楠  薛达元 《生态学报》2014,34(16):4785-4793
传统生态知识是民族生态学研究的核心范畴,国外已有多年的研究基础,国内的相关研究正是方兴未艾。通过文献查询和比较分析等方法,介绍了国外已有的传统生态知识的民族生态学分析框架的3个模型:知识-实践-信仰的三角形框架;本土经验知识-资源管理知识-社会制度知识-世界观知识的四椭圆框架;事实观察-管理体系-旧有及当下利用-伦理价值-文化特征-宇宙观的五边形框架。结合田野调查研究,提出了一个立体的传统生态知识的民族生态学分析模型,强调了传统生态知识的动态特征,将民族对于自然的被动认识和主动认知、民族人际关系规范、民族的哲学与伦理等方面所呈现出的传统生态知识进行了分类,从而为民族生态学的调查研究提供了方法上的建议。最后总结了这个立体的传统生态知识分析框架的意义,并建议在我国的生态文明建设中发展和应用民族生态学。  相似文献   

12.
Concepts of development are inevitably loaded with value judgements concerning what constitutes ‘proper’ social and economic organisation. Focusing on the cultural politics of development on Siquijor, an island in the Central Visayas region of the Philippines, this paper explores these often tacit ideals. It considers one of the key idioms Siquijodnon use in explaining how development is brought about—cooperation—and some of its locally perceived opposites—‘crab mentality’, politicking and corruption—which contain powerful moral critiques of self and society. On Siquijor, local discourses of development have it that widespread poverty in the Philippines demonstrates a failing of Filipinos to live up to supposedly universal norms of ethical socio‐economic conduct. However, I argue that attention to local norms of moral economy reveal the ambivalence underlying these notions of development, particularly in relation to the roles of individualism and reciprocity in socio‐economic organisation.  相似文献   

13.
Institutions to sustain ecological and social systems   总被引:5,自引:0,他引:5  
Summary The foundation for a sustainable future is the continuation of ecological processes and functions across landscapes dominated by human activity; whether hunter-gathering, agriculture, pastoralism, suburban living, commercial and industrial centres or wilderness recreation. However, actions to sustain ecological systems, flows and functions must be integrated across the human dimensions of regional landscapes. Such regions encompass natural areas, human living places and a mosaic of other land uses. Institutional change is required to develop new organizational forms, adjust policies and develop adaptive capacity to demonstrate restoration and maintenance of all forms of social, economic and ecological capital. No matter where on the globe, future sustainability will depend on the system of resource governance that mediates the relationship between the society and the economy and, in contrast, the continuation of ecosystem functional processes. The present article examines the forms of capital, social and institutional change that need to be considered to make progress towards sustainable futures. The discussion further considers the spatial management context in which these interweaved social, ecological and economic processes take place.
Key words ecological, forms of capital, governance, institutions, landscape, social.  相似文献   

14.
This article explores how anthropogenic modifications of soil condition human adaptive processes on the Amazonian uplands. The occurrence of black earth (a nutrient-rich anthrosol) in nutrient-poor blackwater environments and its cultivation by contemporary residents provide a unique opportunity for understanding the ecological praxis of Amazonian groups. Two years of ethnographic, ethnoscientific, and agronomic research among caboclo residents of the Lower Rio Negro and Rio Urubú confirm that unique cognitive and behavioral orientations characterize black earth and adjacent environments. When compared with cognitive and behavioral orientations to these two environments in distant blackwater regions, data suggest that political-economic, technological, cultural, and ecological factors have had~a strong influence on the trajectory of human-environmental interactions. Data in large part illustrate the utility of historical ecological models, yet point to an interactive role of diverse histories in shaping the range of human responses.  相似文献   

15.
Anthropologists have long recognized that breastfeeding involves much more than feeding; it entails intimate social interactions between infants or children and their mothers. However, breastfeeding has predominantly been studied with respect to structural features (frequency, timing) as well as nutritional and health aspects of infant feeding. Thus, in this study we complement previous anthropological studies by examining social interactions that occur during breastfeeding among the Aka and Bofi foragers and Ngandu and Bofi farmers at various ages (three to four months, nine to ten months, toddlers). Further, we use an integrated biocultural perspective to explore how patterns of breastfeeding and social interactions can be shaped by economic constraints, cultural values, and children's development. Overall, our findings illustrate how biological and cultural factors interact and provide useful explanations of variations in breastfeeding structure and social interactions more so than either perspective alone.  相似文献   

16.
Traditional investigations of the evolution of human social and political institutions trace their ancestry back to nineteenth century social scientists such as Herbert Spencer, and have concentrated on the increase in socio-political complexity over time. More recent studies of cultural evolution have been explicitly informed by Darwinian evolutionary theory and focus on the transmission of cultural traits between individuals. These two approaches to investigating cultural change are often seen as incompatible. However, we argue that many of the defining features and assumptions of 'Spencerian' cultural evolutionary theory represent testable hypotheses that can and should be tackled within a broader 'Darwinian' framework. In this paper we apply phylogenetic comparative techniques to data from Austronesian-speaking societies of Island South-East Asia and the Pacific to test hypotheses about the mode and tempo of human socio-political evolution. We find support for three ideas often associated with Spencerian cultural evolutionary theory: (i) political organization has evolved through a regular sequence of forms, (ii) increases in hierarchical political complexity have been more common than decreases, and (iii) political organization has co-evolved with the wider presence of hereditary social stratification.  相似文献   

17.
Global Scenarios: Background Review for the Millennium Ecosystem Assessment   总被引:1,自引:0,他引:1  
Paul D. Raskin 《Ecosystems》2005,8(2):133-142
The long-range outlook for the world’s ecosystems depends on the course taken by global development in the coming decades. Current global trends and ecological dynamics are consistent with very different outcomes, defined by alternative assumptions about the technological, economic, demographic, geopolitical, and social aspects of development and the ways in which institutions, personal and public values, and natural systems may be expected to respond to historically novel stressors. Recent advances in scenario analysis have addressed the dual methodological challenge of exploring these uncertainties in an organized way and determining what would be needed to make the transition to sustainability. This paper reviews global scenario research, setting current efforts in a historical context. It focuses on seven recent studies that are comprehensive, regionally disaggregated, and narratively rich—and thus of greatest relevance to the Millennium Ecosystem Assessment (MA). It summarizes their social visions and the level of quantitative detail used in these exercises. Taken together, this suite of global scenario studies provides a useful platform for the MA by offering insight into the complex factors that drive ecosystem change, estimating the magnitude of regional pressures on ecosystems, sounding the alert on critical uncertainties that could undermine sustainable development, and understanding the importance of institutions and values. But these studies are only a point of departure. The integration of changing ecosystem conditions into global development scenarios, as both effects and causes, is at the cutting edge of scenario analysis. The paper concludes by identifying directions for this research program and suggesting ways that the MA can contribute to this effort.  相似文献   

18.
A number of authors have identified multiple concurrent sexual partnerships by both men and women to lie at the root of the HIV/AIDS epidemic in sub-Saharan Africa. This study applies multilevel models to Demographic and Health Survey data collected during 2003-2008 in 20 sub-Saharan African countries to examine the influence of social and cultural context on involvement with multiple sexual partnerships in the region, above and beyond the effects of individual characteristics. The findings provide support for the ecological argument that health behaviours are shaped and determined by societal conditions, in addition to the effects of individual and household characteristics. Involvement with multiple sex partners is most prevalent in societies in which sexual norms are widely permissive and where polygyny is common. Individual autonomy is substantial and attitudes towards sexuality are more liberal among men and women who live in communities in which sexual norms are widely permissive. Men and women who are most likely to have multiple sex partners in the sub-Saharan region are those who initiated sexual activity earlier and those who have the individual attributes (e.g. young age, urban residence, education, media exposure and working for cash and away from home) that bring to them more rights and/or decision-making autonomy, but not necessarily more financial resources and economic security (mostly among women). On the other hand, involvement with multiple partners is determined by cultural norms (i.e. permissive sexual norms) and social change (i.e. mass education, expansion of cash employment). The findings suggest a number of opportunities for more effective policy and programmatic responses to curb the prevalence of multiple partnerships in sub-Saharan Africa.  相似文献   

19.
黄国勤  王淑彬  赵其国 《生态学报》2014,34(18):5153-5163
生态农业已成为世界农业发展的重要模式和方向。广西生态农业的发展具有基础好、起步早、发展快、模式多、效益佳的特点。从新中国成立至今,广西生态农业经历了4个发展阶段:第一阶段(1949—1977年):群众自发,实践摸索;第二阶段(1978—1991年):模式创新,高产高效;第三阶段(1992—2002年):政府推动,全面推广;第四阶段(2003年至今):模式优化,提质增效。60多年来,广西生态农业发展取得了显著的经济效益、生态效益和社会效益,具体表现在:增加产量、提高效益、改善品质、节约资源、保护环境、提升人员素质、扩大国内外影响等7个方面。当前,广西生态农业存在着6个方面的突出问题:(1)科技薄弱,人才不足;(2)经济落后,资金缺乏;(3)生态脆弱,条件恶劣;(4)技术组装不配套,理论研究不深入;(5)意识不强,措施不力;(6)规模化不够,产业化不强。为使广西生态农业今后又好又快地发展,必须采取如下对策和措施:一是提高认识,转变观念;二是搞好规划,完善制度;三是增加投入,改善条件;四是重视科技,培养人才;五是调整结构,优化模式;六是因地制宜,发挥优势;七是加强交流,开展合作;八是综合配套,全面发展;九是"三效"(经济效益、生态效益和社会效益)并举,良性循环;十是"四化"(规模化、产业化、集约化、科技化)同步,持续发展。  相似文献   

20.
Animals are facing novel ‘timescapes’ in which the stimuli entraining their daily activity patterns no longer match historical conditions due to anthropogenic disturbance. However, the ecological effects (e.g., altered physiology, species interactions) of novel activity timing are virtually unknown. We reviewed 1328 studies and found relatively few focusing on anthropogenic effects on activity timing. We suggest three hypotheses to stimulate future research: (i) activity-timing mismatches determine ecological effects, (ii) duration and timing of timescape modification influence effects, and (iii) consequences of altered activity timing vary biogeographically due to broad-scale variation in factors compressing timescapes. The continued growth of sampling technologies promises to facilitate the study of the consequences of altered activity timing, with emerging applications for biodiversity conservation.  相似文献   

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