Volunteering as Red Queen mechanism for cooperation in public goods games

The evolution of cooperation among nonrelated individuals is one of the fundamental problems in biology and social sciences. Reciprocal altruism fails to provide a solution if interactions are not repeated often enough or groups are too large. Punishment and reward can be very effective but require that defectors can be traced and identified. Here we present a simple but effective mechanism operating under full anonymity. Optional participation can foil exploiters and overcome the social dilemma. In voluntary public goods interactions, cooperators and defectors will coexist. We show that this result holds under very diverse assumptions on population structure and adaptation mechanisms, leading usually not to an equilibrium but to an unending cycle of adjustments (a Red Queen type of evolution). Thus, voluntary participation offers an escape hatch out of some social traps. Cooperation can subsist in sizable groups even if interactions are not repeated, defectors remain anonymous, players have no memory, and assortment is purely random.     

Via freedom to coercion: the emergence of costly punishment

In human societies, cooperative behavior in joint enterprises is often enforced through institutions that impose sanctions on defectors. Many experiments on so-called public goods games have shown that in the absence of such institutions, individuals are willing to punish defectors, even at a cost to themselves. Theoretical models confirm that social norms prescribing the punishment of uncooperative behavior are stable-once established, they prevent dissident minorities from spreading. But how can such costly punishing behavior gain a foothold in the population? A surprisingly simple model shows that if individuals have the option to stand aside and abstain from the joint endeavor, this paves the way for the emergence and establishment of cooperative behavior based on the punishment of defectors. Paradoxically, the freedom to withdraw from the common enterprise leads to enforcement of social norms. Joint enterprises that are compulsory rather than voluntary are less likely to lead to cooperation.     

技术标准设定动因下高技术企业外部协作R&D网络管理能力研究

结合技术标准设定与高技术产业的特性,在分析技术标准设定动因下高技术企业外部协作R&D网络特点的基础上,从技术标准研制的网络化过程角度,探讨了网络管理能力。指出了,在技术标准设定背景下,网络管理能力可分解为基于产业链激发协作能力、设计协作能力、保护协作者贡献可持续力能力和平衡网络成员贡献与利益能力四种能力,以及这四种能力所涵盖的主要网络管理任务。最后,立足于我国的追赶战略与国情,提出了培育与提升技术标准外部协作R&D网络管理能力建议。     

Breeding together: kin selection and mutualism in cooperative vertebrates

In cooperatively breeding vertebrates, nonbreeding helpers raise young produced by dominant breeders. Although the evolution of cooperative breeding has often been attributed primarily to kin selection (whereby individuals gain "indirect" benefits to their fitness by assisting collateral relatives), there is increasing evidence that helpers can be unrelated to the young they are raising. Recent studies also suggest that the indirect benefits of cooperative behavior may often have been overestimated while the direct benefits of helping to the helper's own fitness have probably been underestimated. It now seems likely that the evolutionary mechanisms maintaining cooperative breeding are diverse and that, in some species, the direct benefits of helping may be sufficient to maintain cooperative societies. The benefits of cooperation in vertebrate societies may consequently show parallels with those in human societies, where cooperation between unrelated individuals is frequent and social institutions are often maintained by generalized reciprocity.     

Cooperation through image scoring in humans

The "tragedy of the commons," that is, the selfish exploitation of resources in the public domain, is a reason for many of our everyday social conflicts. However, humans are often more helpful to others than evolutionary theory would predict, unless indirect reciprocity takes place and is based on image scoring (which reflects the way an individual is viewed by a group), as recently shown by game theorists. We tested this idea under conditions that control for confounding factors. Donations were more frequent to receivers who had been generous to others in earlier interactions. This shows that image scoring promotes cooperative behavior in situations where direct reciprocity is unlikely.     

山西省农民专业合作社典型模式研究

围绕目前山西省农民专业合作社存在的4种典型模式进行案例介绍、深入剖析和研究,总结了山西省农民专业合作社呈现出的模式多样化、规模领域扩大化、联结紧密化、服务多样化、社会效益显著等特点,并提出了推进农民专业合作社发展坚持的原则、途径和保障措施等政策建议。     

Tempo and mode of evolutionary radiation in iguanian lizards

Identification of general properties of evolutionary radiations has been hindered by the lack of a general statistical and phylogenetic approach applicable across diverse taxa. We present a comparative analytical framework for examining phylogenetic patterns of diversification and morphological disparity with data from four iguanian-lizard taxa that exhibit substantially different patterns of evolution. Taxa whose diversification occurred disproportionately early in their evolutionary history partition more of their morphological disparity among, rather than within, subclades. This inverse relationship between timing of diversification and morphological disparity within subclades may be a general feature that transcends the historically contingent properties of different evolutionary radiations.     

Ecological Controls on the Evolutionary Recovery of Post-Paleozoic Crinoids

Analysis of morphological characters of a global sample of post-Paleozoic crinoid echinoderms shows that this group underwent a rapid diversification after the extinction at the end of the Permian to reach maximal morphological disparity by the Late Triassic, which is essentially the same evolutionary pattern seen during the group's early Paleozoic radiation. The accelerated morphological diversification of a single class implies that, even if clades surviving from the Paleozoic represented ecological incumbents that hindered the origin of new higher taxa, species within individual higher taxa rapidly exploited available ecological opportunities in the Mesozoic.     

澳大利亚的稻谷生产者股份制合作社

水稻生产者股份合作社是澳大利亚最成功的生产合作社和澳大利亚 30家最大的出口商之一 .经过几十年的发展 ,它已经成为一个经营有效 ,实力强大的经济实体 ,其特征表现为 :产、加、销垂直一体化经营 ;产品的多样化 ;独特的轮作制 ;严格的隔离措施以及以出口为导向的营销战略 .合作社通过集体行为在生产、加工和营销稻谷方面的成功经验很值得我们借鉴     

基于故障树分析的安全投资决策方法研究

有研究表明增加安全投资能提升安全生产水平。合理地确定安全投资总额、比例及方向,有助于企业以有限地投入获得最佳的安全效果和经济效益。本文首先分析了安全投资决策的主要问题,认为效益分析是安全投资决策的重要环节,即要比较安全投入与产出的关系。以价值工程理论中＂利益—成本＂分析方法为基础,引入故障树分析的基本概念及相关定性、定量分析过程,探讨了故障树分析在安全投资决策中的应用,实例研究结果表明通过故障树分析能够得到比较满意和优化的投资方案,有助于综合权衡安全投入和安全效果,为安全投资决策问题提供了新的途径。     

基于SMS的智能家居远程控制模块设计

利用演化博弈理论，对参与主体异质性条件下的囚徒困境模型进行了探讨，求出了满足不同条件下的演化稳定策略，并对种群中个体异质性对演化稳定策略的影响进行了分析，得出种群中选择相同策略的个体异质性差异越大，参与个体选择合作行为作为演化稳定策略的可能性就越大.极端地，当个体的异质性趋向于无穷大时，合作成为唯一的演化稳定占优策略，为现实大多数合作系统中能保持长期的一种合作稳定状态提供了合理地解释.     

Superiority, competition, and opportunism in the evolutionary radiation of dinosaurs

The rise and diversification of the dinosaurs in the Late Triassic, from 230 to 200 million years ago, is a classic example of an evolutionary radiation with supposed competitive replacement. A comparison of evolutionary rates and morphological disparity of basal dinosaurs and their chief "competitors," the crurotarsan archosaurs, shows that dinosaurs exhibited lower disparity and an indistinguishable rate of character evolution. The radiation of Triassic archosaurs as a whole is characterized by declining evolutionary rates and increasing disparity, suggesting a decoupling of character evolution from body plan variety. The results strongly suggest that historical contingency, rather than prolonged competition or general "superiority," was the primary factor in the rise of dinosaurs.     

农机规模经营投资经济效益分析模型探讨

基于评价指标体系的建立,探讨农机规模经营投资经济效益分析的方法,利用现代管理技术,在参考了工业投资项目评价方法的基础上,总结农机规模经营投资经济效益分析的评价指标,并结合案例加以说明,以为农机规模经营投资评价工作提供参考。     

土地股份合作制对农民增收的影响研究--基于广东省东莞市虎门镇的调查

以广东省东莞市虎门镇农村社区为研究对象,采取实地调研、案例研究方法,分析了当地27个农村土地股份合作制改革状况以及对农民增收的影响,调查结果表明,实行土地股份合作制对农民收入增加存在正面影响,但对不同村庄农民增收的影响和贡献程度不相同,土地股份合作制促进农民增收的绩效水平要受当地地理位置、村干部组织管理水平、招商引资力度、经济发展水平等因素的影响。     

农业产业化经营利益联结机制比较研究——以云南曲靖为例

在分析曲靖市农业产业化发展的现状后,对曲靖农业产业化经营各种利益联结的机制进行比较分析,表明企业与农户间利益联结由＂松散型＂向＂紧密型＂变迁,是市场经济作用的必然。为使农户分享农业产业化发展的成果,提出了＂公司型龙头企业＋农民股份合作组织＂股权式利益联结机制的构建对策。     

十堰市2个烟农专业合作社的比较分析

从组织机构、烟农合作社专业化服务覆盖率、烟农收入及种植情况、减工降本、提质增效各方面对十堰市房县西坪烟农合作社和竹溪向坝合作社2两家烟农专业合作社进行比较分析,从中找出适合十堰市烟农专业合作社的发展模式。结果显示,西坪烟农专业合作社虽然选举产生了理事会,但理事会对合作社事务介入的较少,合作社比较效益相对较低;西坪是村级合作社,竹溪向坝是乡级合作社,从合作社的运行和发展状况来讲,乡级合作社从服务途径和效益都较村级烟农合作社好。     

广西低碳农业发展模式及对策

【目的】总结分析广西低碳农业发展模式及实践成效,为积极发展低碳农业,实现农业可持续发展提供参考。【方法】通过相关文献资料查阅的方法,阐述了低碳农业的概念、内涵及其发展意义,总结广西低碳农业发展模式及实践成效,并提出广西低碳农业发展对策。【结果】广西低碳农业发展模式主要有立体生态循环模式、绿色植保安全模式、科学节肥减排模式、高效节水灌溉模式、免耕栽培节能模式、再生能源替代模式、废弃物综合循环利用模式等,这7种发展模式均取得显著的经济效益和社会效益。【建议】应树立低碳理念、提高低碳意识、加大鼓励扶持、建立健全低碳农业发展政策、积极推动低碳农业多元化发展、加大科技创新、加强宣传培训等,以推动广西低碳农业进一步发展。     

The neural basis of altruistic punishment

Many people voluntarily incur costs to punish violations of social norms. Evolutionary models and empirical evidence indicate that such altruistic punishment has been a decisive force in the evolution of human cooperation. We used H2 15O positron emission tomography to examine the neural basis for altruistic punishment of defectors in an economic exchange. Subjects could punish defection either symbolically or effectively. Symbolic punishment did not reduce the defector's economic payoff, whereas effective punishment did reduce the payoff. We scanned the subjects' brains while they learned about the defector's abuse of trust and determined the punishment. Effective punishment, as compared with symbolic punishment, activated the dorsal striatum, which has been implicated in the processing of rewards that accrue as a result of goal-directed actions. Moreover, subjects with stronger activations in the dorsal striatum were willing to incur greater costs in order to punish. Our findings support the hypothesis that people derive satisfaction from punishing norm violations and that the activation in the dorsal striatum reflects the anticipated satisfaction from punishing defectors.     

Contingency and determinism in replicated adaptive radiations of island lizards

The vagaries of history lead to the prediction that repeated instances of evolutionary diversification will lead to disparate outcomes even if starting conditions are similar. We tested this proposition by examining the evolutionary radiation of Anolis lizards on the four islands of the Greater Antilles. Morphometric analyses indicate that the same set of habitat specialists, termed ecomorphs, occurs on all four islands. Although these similar assemblages could result from a single evolutionary origin of each ecomorph, followed by dispersal or vicariance, phylogenetic analysis indicates that the ecomorphs originated independently on each island. Thus, adaptive radiation in similar environments can overcome historical contingencies to produce strikingly similar evolutionary outcomes.     

绿色技术创新与企业持续发展

在可持续发展思想被越来越多的人接受的背景下，企业发展而临着来自政府、公众、竞争对手以及合作者等多方而的环境压力。绿色技术创新可以通过成木的降低、市场份额的提高、生产规模的扩大以及技术转让收益使企业走出持续发展与环境保护的两难困境。由于企业追逐利润最大化的特性以及技术创新风险大、费用高等特点，需要采取一系列政策和措施推动我国企业积极进行绿色技术创新。