Altruism, Altruistic Punishment and Social Investment

The concept of altruism is used in very different forms by computer scientists,economists, philosophers, social scientists, psychologists and biologists. Yet, in order to be useful in social simulations, the concept "altruism" requires a more precise meaning. A quantitative formulation is proposed here, based on the cost/benefit analysis of the altruist and of society at large. This formulation is applied in the analysis of the social dynamic working of behaviors that have been called "altruistic punishments", using the agent based computer model Sociodynamica. The simulations suggest that "altruistic punishment" on its own cannot maintain altruistic behaviors. "Altruistic behavior" is sustainable in the long term only if these behaviors trigger synergetic forces in society that eventually make them produce benefits to most individuals. The simulations suggest however that "altruistic punishment" may work as a "social investment", and is thus better called "decentralized social punishment". This behavior is very efficient in enforcing social norms. The efficiency of decentralized social punishment in enforcing norms was dependent on the type of labor structured of the virtual society. I conclude that what is called "altruistic punishment" emerges as a type of social investment that can evolve either through individual and/or group selection, as a successful device for changing or enforcing norms in a society. Social simulations will help us in better understanding the underlying dynamic working of such devices.     

Sex,Attractiveness, and Third-Party Punishment in Fairness Consideration

Social evaluation of others is often influenced by the physical attractiveness of the person being judged, leading to either a beauty premium or penalty depending on the circumstances. Here we asked Chinese participants to act as an interest-free third party in a dictator game and to evaluate the fairness level of monetary allocation by attractive and less attractive proposers of the same or opposite sex. We also instructed participants to express their willingness to punish the proposers by using a visual analogue scale. Results confirmed that the reasonableness evaluation was mainly affected by the reasonableness of offers. However, participants'' intention to punish the proposers was affected by the level of reasonableness in the asset distribution and by both the sex and attractiveness of the proposers. Overall, male proposers were punished more severely than female proposers. Moreover, the same-sex proposers were punished more severely than opposite-sex proposers when they were physically attractive; this pattern was reversed when the proposers were less physically attractive. These results demonstrate social responses following an individual''s unfair asset distribution can be affected by both social norms and the personal characteristics of the individual.     

The Role of Compassion in Altruistic Helping and Punishment Behavior

Compassion, the emotional response of caring for another who is suffering and that results in motivation to relieve suffering, is thought to be an emotional antecedent to altruistic behavior. However, it remains unclear whether compassion enhances altruistic behavior in a uniform way or is specific to sub-types of behavior such as altruistic helping of a victim or altruistic punishment of a transgressor. We investigated the relationship between compassion and subtypes of altruistic behavior using third-party paradigms where participants 1) witnessed an unfair economic exchange between a transgressor and a victim, and 2) had the opportunity to either spend personal funds to either economically a) help the victim or b) punish the transgressor. In Study 1, we examined whether individual differences in self-reported empathic concern (the emotional component of compassion) was associated with greater altruistic helping or punishment behavior in two independent samples. For participants who witnessed an unfair transaction, trait empathic concern was associated with greater helping of a victim and had no relationship to punishment. However, in those who decided to punish the transgressor, participants who reported greater empathic concern decided to punish less. In Study 2, we directly enhanced compassion using short-term online compassion meditation training to examine whether altruistic helping and punishment were increased after two weeks of training. Compared to an active reappraisal training control group, the compassion training group gave more to help the victim and did not differ in punishment of the transgressor. Together, these two studies suggest that compassion is related to greater altruistic helping of victims and is not associated with or may mitigate altruistic punishment of transgressors.     

The Co-Evolution of Fairness Preferences and Costly Punishment

We study the co-evolutionary emergence of fairness preferences in the form of other-regarding behavior and its effect on the origination of costly punishment behavior in public good games. Our approach closely combines empirical results from three experiments with an evolutionary simulation model. In this way, we try to fill a gap between the evolutionary theoretical literature on cooperation and punishment on the one hand and the empirical findings from experimental economics on the other hand. As a principal result, we show that the evolution among interacting agents inevitably favors a sense for fairness in the form of “disadvantageous inequity aversion”. The evolutionary dominance and stability of disadvantageous inequity aversion is demonstrated by enabling agents to co-evolve with different self- and other-regarding preferences in a competitive environment with limited resources. Disadvantageous inequity aversion leads to the emergence of costly (“altruistic”) punishment behavior and quantitatively explains the level of punishment observed in contemporary lab experiments performed on subjects with a western culture. Our findings corroborate, complement, and interlink the experimental and theoretical literature that has shown the importance of other-regarding behavior in various decision settings.     

鸟类基因组核苷酸频数的进化模型

鸟类是四足类动物中最丰富的一类脊椎动物,本研究以12种鸟类的全基因组核苷酸序列数据为研究对象,建立核苷酸频数进化方程,研究了鸟类基因组核苷酸频数的进化机制和规律。通过拟合基因组数据确定了方程中的进化惯性参数、耗散参数和环境参数,估算出进化速率,得到了基因组长度随时间的演化曲线,解出了基因组在短时间内快速增加,信息快速积累,然后进入进化停滞阶段,核苷酸频数不再明显变化。本研究的方法为定量研究鸟类和一般物种的进化提供了新的思路。     

An Evolutionary Cascade Model for Sauropod Dinosaur Gigantism - Overview,Update and Tests

Sauropod dinosaurs are a group of herbivorous dinosaurs which exceeded all other terrestrial vertebrates in mean and maximal body size. Sauropod dinosaurs were also the most successful and long-lived herbivorous tetrapod clade, but no abiological factors such as global environmental parameters conducive to their gigantism can be identified. These facts justify major efforts by evolutionary biologists and paleontologists to understand sauropods as living animals and to explain their evolutionary success and uniquely gigantic body size. Contributions to this research program have come from many fields and can be synthesized into a biological evolutionary cascade model of sauropod dinosaur gigantism (sauropod gigantism ECM). This review focuses on the sauropod gigantism ECM, providing an updated version based on the contributions to the PLoS ONE sauropod gigantism collection and on other very recent published evidence. The model consist of five separate evolutionary cascades (“Reproduction”, “Feeding”, “Head and neck”, “Avian-style lung”, and “Metabolism”). Each cascade starts with observed or inferred basal traits that either may be plesiomorphic or derived at the level of Sauropoda. Each trait confers hypothetical selective advantages which permit the evolution of the next trait. Feedback loops in the ECM consist of selective advantages originating from traits higher in the cascades but affecting lower traits. All cascades end in the trait “Very high body mass”. Each cascade is linked to at least one other cascade. Important plesiomorphic traits of sauropod dinosaurs that entered the model were ovipary as well as no mastication of food. Important evolutionary innovations (derived traits) were an avian-style respiratory system and an elevated basal metabolic rate. Comparison with other tetrapod lineages identifies factors limiting body size.     

Exit,Punishment and Rewards in Commons Dilemmas: An Experimental Study

Commons dilemmas are interaction situations where a common good is provided or exploited by a group of individuals so that optimal collective outcomes clash with private interests. Although in these situations, social norms and institutions exist that might help individuals to cooperate, little is known about the interaction effects between positive and negative incentives and exit options by individuals. We performed a modified public good game experiment to examine the effect of exit, rewards and punishment, as well as the interplay between exit and rewards and punishment. We found that punishment had a stronger effect than rewards on cooperation if considered by itself, whereas rewards had a stronger effect when combined with voluntary participation. This can be explained in terms of the ‘framing effect’, i.e., as the combination of exit and rewards might induce people to attach higher expected payoffs to cooperative strategies and expect better behaviour from others.     

公立医院与社会资本的合作之势在“何”行

在国家和地方的政策强力推动下,以社会资本进入医疗领域为核心的改革成为医改主要方向。对公立医院与社会资本合作的有效模式的积极探索对于主要的利益相关方将有明显的多赢效应。在实际合作过程中,需要从经营理念的转换、战略方向的把握、试点资格的审核和政策的支持等方面进行不断地磨合与探索。     

Deception Undermines the Stability of Cooperation in Games of Indirect Reciprocity

Indirect reciprocity is often claimed as one of the key mechanisms of human cooperation. It works only if there is a reputational score keeping and each individual can inform with high probability which other individuals were good or bad in the previous round. Gossip is often proposed as a mechanism that can maintain such coherence of reputations in the face of errors of transmission. Random errors, however, are not the only source of uncertainty in such situations. The possibility of deceptive communication, where the signallers aim to misinform the receiver cannot be excluded. While there is plenty of evidence for deceptive communication in humans the possibility of deception is not yet incorporated into models of indirect reciprocity. Here we show that when deceptive strategies are allowed in the population it will cause the collapse of the coherence of reputations and thus in turn it results the collapse of cooperation. This collapse is independent of the norms and the cost and benefit values. It is due to the fact that there is no selection for honest communication in the framework of indirect reciprocity. It follows that indirect reciprocity can be only proposed plausibly as a mechanism of human cooperation if additional mechanisms are specified in the model that maintains honesty.     

An Evolutionary Firefly Algorithm for the Estimation of Nonlinear Biological Model Parameters

The development of accurate computational models of biological processes is fundamental to computational systems biology. These models are usually represented by mathematical expressions that rely heavily on the system parameters. The measurement of these parameters is often difficult. Therefore, they are commonly estimated by fitting the predicted model to the experimental data using optimization methods. The complexity and nonlinearity of the biological processes pose a significant challenge, however, to the development of accurate and fast optimization methods. We introduce a new hybrid optimization method incorporating the Firefly Algorithm and the evolutionary operation of the Differential Evolution method. The proposed method improves solutions by neighbourhood search using evolutionary procedures. Testing our method on models for the arginine catabolism and the negative feedback loop of the p53 signalling pathway, we found that it estimated the parameters with high accuracy and within a reasonable computation time compared to well-known approaches, including Particle Swarm Optimization, Nelder-Mead, and Firefly Algorithm. We have also verified the reliability of the parameters estimated by the method using an a posteriori practical identifiability test.     

Evolutionary Psychology, Human Universals, and the Standard Social Science Model

Proponents of evolutionary psychology take the existence of humanuniversals to constitute decisive evidence in favor of their view. Ifthe same social norms are found in culture after culture, we have goodreason to believe that they are innate, they argue. In this paper Ipropose an alternative explanation for the existence of humanuniversals, which does not depend on them being the product of inbuiltpsychological adaptations. Following the work of Brian Skyrms, I suggestthat if a particular convention possesses even a very small advantageover competitors, whatever the reason for that advantage, we shouldexpect it to become the norm almost everywhere. Tiny advantages aretranslated into very large basins of attraction, in the language of gametheory. If this is so, universal norms are not evidence for innatepsychological adaptations at all. Having shown that the existence ofuniversals is consistent with the so-called Standard Social ScienceModel, I turn to a consideration of the evidence, to show that thisstyle of explanation is preferable to the evolutionary explanation, atleast with regard to patterns of gender inequality.     

Cooperative Equilibrium in Biosphere Evolution: Reconciling Competition and Cooperation in Evolutionary Ecology

Acta Biotheoretica - As our understanding of biological evolution continues to deepen, tension still surrounds the relationship between competition and cooperation in the evolution of the...     

Postnatal Cranial Development in Papionin Primates: An Alternative Model for Hominin Evolutionary Development

The evolution of hominin growth and life history has long been a subject of intensive research, but it is only recently that paleoanthropologists have considered the ontogenetic basis of human morphological evolution. To date, most human EvoDevo studies have focused on developmental patterns in extant African apes and humans. However, the Old World monkey tribe Papionini, a diverse clade whose members resemble hominins in their ecology and population structure, has been proposed as an alternative model for human craniofacial evolution. This paper reviews prior studies of papionin development and socioecology and presents new analyses of juvenile shape variation and ontogeny to address fundamental questions concerning primate cranial development, including: (1) When are cranial shape differences between species established? (2) How do epigenetic influences modulate early-arising pattern differences? (3) How much do postnatal developmental trajectories vary? (4) What is the impact of developmental variation on adult cranial shape? and, (5) What role do environmental factors play in establishing adult cranial form? Results of this inquiry suggest that species differences in cranial morphology arise during prenatal or earliest postnatal development. This is true even for late-arising features that develop under the influence of epigenetic factors such as mechanical loading. Papionins largely retain a shared, ancestral pattern of ontogenetic shape change, but large size and sexual dimorphism are associated with divergent developmental trajectories, suggesting differences in cranial integration. Developmental simulation studies indicate that postnatal ontogenetic variation has a limited influence on adult cranial morphology, leaving early morphogenesis as the primary determinant of cranial shape. The ability of social factors to influence craniofacial development in Mandrillus suggests a possible role for phentotypic plasticity in the diversification of primate cranial form. The implications of these findings for taxonomic attribution of juvenile fossils, the developmental basis of early hominin characters, and hominin cranial diversity are discussed.     

Mapping Biological Transmission: An Empirical,Dynamical, and Evolutionary Approach

The current debate over extending inheritance and its evolutionary impact has focused on adding new categories of non-genetic factors to the classical transmission of DNA, and on trying to redefine inheritance. Transmitted factors have been mainly characterized by their directions of transmission (vertical, horizontal, or both) and the way they store variations. In this paper, we leave aside the issue of defining inheritance. We rather try to build an evolutionary conceptual framework that allows for tracing most, if not all forms of transmission and makes sense of their different tempos and modes. We discuss three key distinctions that should in particular be the targets of theoretical and empirical investigation, and try to assess the interplay among them and evolutionary dynamics. We distinguish two channels of transmission (channel 1 and channel 2), two measurements of the temporal dynamics of transmission, respectively across and within generations (durability and residency), and two types of transmitted factors according to their evolutionary relevance (selectively relevant and neutral stable factors). By implementing these three distinctions we can then map different forms of transmission over a continuous space describing the combination of their varying dynamical features. While our aim is not to provide yet another model of inheritance, putting together these distinctions and crossing them, we manage to offer an inclusive conceptual framework of transmission, grounded in empirical observation, and coherent with evolutionary theory. This interestingly opens possibilities for qualitative and quantitative analyses, and is a necessary step, we argue, in order to question the interplay between the dynamics of evolution and the dynamics of multiple forms of transmission.     

Parental Use of Corporal Punishment in Europe: Intersection between Public Health and Policy

Studies have linked the use of corporal punishment of children to the development of mental health disorders. Despite the recommendation of international governing bodies for a complete ban of the practice, there is little European data available on the effects of corporal punishment on mental health and the influence of laws banning corporal punishment. Using data from the School Children Mental Health Europe survey, the objective of this cross-sectional study was to examine the prevalence and legal status of corporal punishment across six European countries and to evaluate the association between parental use of corporal punishment and children’s mental health. The study found that odds of having parents who reported using occasional to frequent corporal punishment were 1.7 times higher in countries where its use is legal, controlling for socio-demographic factors. Children with parents who reported using corporal punishment had higher rates of both externalized and internalized mental health disorders.     

Celebrate Darwin Day, An Event for Education and Outreach in Evolutionary Biology

Darwin Day is an international celebration of Charles Darwin’s birthday, February 12, and is used as an occasion for education and outreach in evolutionary biology. I describe the history and structure of Darwin Day at the University of Tennessee, one of the oldest Darwin Day organizations in the world. I detail past events including speakers, themes, and advertising ideas that have worked for us and suggestions for getting a Darwin Day started. I encourage interested groups especially those at schools, museums, libraries, nature centers, and other institutions to adapt ideas from our organization to fit their own circumstances and to start planning their own Darwin Days for the celebration of Darwin’s 200th birthday in 2009.     

Quantifying the Role of Homophily in Human Cooperation Using Multiplex Evolutionary Game Theory

Nature shows as human beings live and grow inside social structures. This assumption allows us to explain and explore how it may shape most of our behaviours and choices, and why we are not just blindly driven by instincts: our decisions are based on more complex cognitive reasons, based on our connectedness on different spaces. Thus, human cooperation emerges from this complex nature of social network. Our paper, focusing on the evolutionary dynamics, is intended to explore how and why it happens, and what kind of impact is caused by homophily among people. We investigate the evolution of human cooperation using evolutionary game theory on multiplex. Multiplexity, as an extra dimension of analysis, allows us to unveil the hidden dynamics and observe non-trivial patterns within a population across network layers. More importantly, we find a striking role of homophily, as the higher the homophily between individuals, the quicker is the convergence towards cooperation in the social dilemma. The simulation results, conducted both macroscopically and microscopically across the network layers in the multiplex, show quantitatively the role of homophily in human cooperation.     

Social Learning and the Maintenance of Cultural Variation: An Evolutionary Model and Data from East Africa

Human societies maintain between-group variation despite mixing of people and ideas. In order for variation to remain, migrants or their children must preferentially adopt local norms, customs, and beliefs. Yet the details of how cultural variation is maintained, despite mixing, remain unknown. This article addresses this problem by using a simple model of the evolution of cultural learning to interpret the results of a study of cultural variation in a small region of East Africa. I argue that the manner in which migrants of two diverse regions adapt to local beliefs and behavior depends on the costs and accuracy of learning in each domain. Observational studies are never definitive tests of any hypothesis, but these results suggest that conclusions about the significance of cultural learning for understanding individual attitudes and behavior depend strongly upon the domain of investigation.     

Evolutionary Morphology, Innovation, and the Synthesis of Evolutionary and Developmental Biology

One foundational question in contemporarybiology is how to `rejoin evolution anddevelopment. The emerging research program(evolutionary developmental biology or`evo-devo) requires a meshing of disciplines,concepts, and explanations that have beendeveloped largely in independence over the pastcentury. In the attempt to comprehend thepresent separation between evolution anddevelopment much attention has been paid to thesplit between genetics and embryology in theearly part of the 20th century with itscodification in the exclusion of embryologyfrom the Modern Synthesis. This encourages acharacterization of evolutionary developmentalbiology as the marriage of evolutionary theoryand embryology via developmental genetics. Butthere remains a largely untold story about thesignificance of morphology and comparativeanatomy (also minimized in the ModernSynthesis). Functional and evolutionarymorphology are critical for understanding thedevelopment of a concept central toevolutionary developmental biology,evolutionary innovation. Highlighting thediscipline of morphology and the concepts ofinnovation and novelty provides an alternativeway of conceptualizing the `evo and the `devoto be synthesized.     

A Model of Human Cooperation in Social Dilemmas

Social dilemmas are situations in which collective interests are at odds with private interests: pollution, depletion of natural resources, and intergroup conflicts, are at their core social dilemmas. Because of their multidisciplinarity and their importance, social dilemmas have been studied by economists, biologists, psychologists, sociologists, and political scientists. These studies typically explain tendency to cooperation by dividing people in proself and prosocial types, or appealing to forms of external control or, in iterated social dilemmas, to long-term strategies. But recent experiments have shown that cooperation is possible even in one-shot social dilemmas without forms of external control and the rate of cooperation typically depends on the payoffs. This makes impossible a predictive division between proself and prosocial people and proves that people have attitude to cooperation by nature. The key innovation of this article is in fact to postulate that humans have attitude to cooperation by nature and consequently they do not act a priori as single agents, as assumed by standard economic models, but they forecast how a social dilemma would evolve if they formed coalitions and then they act according to their most optimistic forecast. Formalizing this idea we propose the first predictive model of human cooperation able to organize a number of different experimental findings that are not explained by the standard model. We show also that the model makes satisfactorily accurate quantitative predictions of population average behavior in one-shot social dilemmas.