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The evolution of altruism: Game theory in multilevel selection and inclusive fitness
Abstract
Although the prisoner's dilemma (PD) has been used extensively to study reciprocal altruism, here we show that the n-player prisoner's dilemma (NPD) is also central to two other prominent theories of the evolution of altruism: inclusive fitness and multilevel selection. An NPD model captures the essential factors for the evolution of altruism directly in its parameters and integrates important aspects of these two theories such as Hamilton's rule, Simpson's paradox, and the Price covariance equation. The model also suggests a simple interpretation of the Price selection decomposition and an alternative decomposition that is symmetrical and complementary to it. In some situations this alternative shows the temporal changes in within- and between-group selection more clearly than the Price equation. In addition, we provide a new perspective on strong vs. weak altruism by identifying their different underlying game structures (based on absolute fitness) and showing how their evolutionary dynamics are nevertheless similar under selection (based on relative fitness). In contrast to conventional wisdom, the model shows that both strong and weak altruism can evolve in periodically formed random groups of non-conditional strategies if groups are multigenerational. An integrative approach based on the NPD helps unify different perspectives on the evolution of altruism.
... It is clear from this equation that p 1 > 0 is a sufficient condition for r c > 0 and thus for the existence of an allcooperators regime. Equation (43) has been derived in a much less transparent way for the uniform distribution and then assumed to hold true for non-uniform distributions as well [24]. Our elementary derivation of Eq. (43), which is essentially the condition for the stability of the all-cooperators fixed point, proves that it is indeed valid in general. ...
... Equation (43) has been derived in a much less transparent way for the uniform distribution and then assumed to hold true for non-uniform distributions as well [24]. Our elementary derivation of Eq. (43), which is essentially the condition for the stability of the all-cooperators fixed point, proves that it is indeed valid in general. ...
... As for the Nperson games, see Eqs. (2) and (3), the binomial distribution is the usual choice to model the composition of the trait groups [42]. Although game theory, and in particular the N -person prisoner's dilemma, has already proven useful in integrating elements (e.g., Hamilton's rule and the Price equation) of multilevel selection and inclusive fitness theories for the evolution of altruism [43], the connection between the replicator equation and Wilson's trait group framework seems to go unnoticed. A fundamental result of Wilson's approach is that cooperation is promoted by increasing the variability of group composition or, if fitness is not a linear function of the number of cooperators, by increasing the variance of a cooperator's fitness. ...
Understanding the conditions for maintaining cooperation in groups of unrelated individuals despite the presence of non-cooperative members is a major research topic in contemporary biological, sociological, and economic theory. The N-person snowdrift game models the type of social dilemma where cooperative actions are costly, but there is a reward for performing them. We study this game in a scenario where players move between play groups following the casual group dynamics, where groups grow by recruiting isolates and shrink by losing individuals who then become isolates. This describes the size distribution of spontaneous human groups and also the formation of sleeping groups in monkeys. We consider three scenarios according to the probability of isolates joining a group. We find that for appropriate choices of the cost-benefit ratio of cooperation and the aggregation-disaggregation ratio in the formation of casual groups, free-riders can be completely eliminated from the population. If individuals are more attracted to large groups, we find that cooperators persist in the population even when the mean group size diverges. We also point out the remarkable similarity between the replicator equation approach to public goods games and the trait group formulation of structured demes.
... Nash equilibrium is said to occur when no player has an incentive to deviate from his or her chosen strategy after considering an opponent's choice. Recent studies that have incorporated spatial dependence in the paradoxical prisoner's dilemma (PD) are, among others, the spatial distribution of individuals on the outcome of competition in Durrett and Levin (1998), the evolution of cooperation within the strategy space of all stochastic strategies in Brauchli, Killingback and Doebeli (1999), the spatial competition in China's higher education system (Jiafeng 2012a(Jiafeng , 2012c, the spatial interaction among China's counties (Jiafeng 2012b) and altruism in Fletcher and Zwick (2007). There was clear indication that this pricing behavior of universities was shaped by evolution of a spatial game in which the price one university chooses depended on its neighboring universities' prices. ...
... We compute Moran's I values of all prices including tuition fees, room and board and total expenses in the 2008-2009 school year with k-nearest neighbor spatial weights (k = 1, 2, …, 30), which are illustrated in Figure 1. Moran's I value is not a direct indicator measuring the degree of reciprocal altruism, however, it can measure the interaction intensiveness and frequency among players in a spatial game, which reflects the predisposition to reciprocal altruism because players with more intensive and frequent interactions are more likely to show altruism (Rotemberg 2008;Fletcher and Zwick 2007), and are more likely to form some kind of collusion. Experimental control is particularly useful because game theory predictions often depend sensitively on the choices players have, how they value outcomes, what they know, the order in which they move, and so forth. ...
... As the neighbor size increases, the cooperation rate and the defeat rate both increase while the C/D rate will converge to 3.22, which shows the possibility of cooperation equilibrium is 76% and the possibility of defeat equilibrium is 24%. Our study confirms the judgment that human society is based to a large extent on mechanisms that promote cooperation (Fletcher and Zwick 2007;Clemens and Riechmann 2006;Sanchez and Cuesta 2005). ...
How geographical neighboring competitors influence the strategic price behaviors of universities is still unclear because previous studies assume spatial independence between universities. Using data from the National Center for Education Statistics college navigator dataset, this study shows that the price of one university is spatially autocorrelated to its neighboring competitors and such neighborhood structure induces cooperation Nash equilibrium in a spatial price game. In the spatial price game of universities the possibility of the cooperation solution is about 76%, while that of the defeat solution is about 24%. This study demonstrates that the relation between price difference and geographical distance of universities is an inverse U-shaped curve rather than a line.
... Much previous work has investigated the role of different rates of migration on assortment and the evolution of cooperation, but systematic migration has been explored only in a few models (Avilés 2002;Pepper & Smuts 1999;Pepper & Smuts 2002). It has also been shown that periodic group reformation events, in which all individuals are randomly redistributed to groups, can favor altruism when they occur as defectors are just beginning to invade altruistic groups (Fletcher & Zwick 2004;Fletcher & Zwick 2007). The Walk Away rule presented here can promote the effective timing of these group reformation events because individuals begin to leave groups as the level of cooperation in the present group dips below the threshold. ...
... The fundamental principles of multi-level selection can be understood in the context of a social dilemma (Fletcher & Zwick 2007): within a group of individuals who exert fitness effects on one another, selection will favor those who do not deliver benefits to the group at a cost to themselves because these individuals will enjoy higher withingroup fitness. However, groups that consist of individuals who provide fitness benefits within the group can increase in size more quickly than groups with fewer such individuals. ...
... The model presented in the final section (Figures 3.8 and 3.9) suggest that the Walk Away rule establishes a feedback loop between the proportion of cooperators and stability which both selects for cooperation and helps to maintain it. In Fletcher and Zwick (2007), the time between group reformation events was varied parametrically and they found that cooperation could be favored if group reformation occurred as defectors began to be selected. The Walk Away rule might serve as a decentralized mechanism that can promote such regrouping events when the between group selection component (favoring cooperators) would otherwise be outweighed by selection within groups (favoring defectors). ...
Cooperation among group members, coworkers and community members can provide benefits for all involved parties. However, groups of all kinds are plagued by free riders, or individuals who take advantage of cooperative group members by benefiting from being a part of the group without contributing, resulting in a social dilemma or 'tragedy of the commons.' This phenomenon is not unique to humans; free riders can be identified in organisms as simple as bacteria. This has lead to the puzzling question of how cooperation is maintained in social groups of humans and other animals, given higher payoffs for free riding than for cooperation. In order to address this question, I simulate individuals who use a simple Walk Away rule to leave uncooperative partners or groups, and show that cooperation is favored under a variety of parameter values when agents can use this rule. When agents use the Walk Away rule, more cooperative partnerships and groups are more stable than less cooperative ones. This promotes assortment, or the preferential interaction of cooperators with one another, which favors the evolution of cooperation. It is shown that in dyadic partnerships Walk Away can outperform the well-known Tit-for-Tat strategy. In group-wise interactions, the Walk Away rule generates large number of relatively small groups and differential group stability based on average cooperativeness. These features maintain selection for cooperation by generating population structures that promote group selection. The simple Walk Away rule does not require complex individual level abilities such as long-term memory, recognition of group members or punishment, suggesting that complex cognitive abilities are not necessary for cooperation to be promoted.
... In contrast, strong altruism has "other-only" traits because there is an absolute cost to the actor. Some other sociobiologists will avoid using the term "altruism" when there is not an absolute fitness sacrifice and rather prefer using the term "benevolence" to talk about "weak altruism" (Fletcher and Zwick 2007). Because of its paradoxical evolution, altruism remains a mystery. ...
... The classical game theory states that individuals always try to maximize their relative fitness in any situation (Fletcher and Zwick 2007). However, the definition of altruism explains that this behaviour puts the altruist at a disadvantage. ...
Any behaviour that benefit an individual at a fitness cost for the actor is said to be altruistic. Altruism, which should be selected against by natural selection because it decreases the fitness of the donor, is an interesting mystery that scientists have been trying to solve for decades. In this paper, I make a review of many scientific articles, from the first theories to the recent molecular researches. I focus on the debate about individual and group selection to conclude that there are many levels of selection, from genes to groups. Different types of altruism exist, and coexist. Finally, thanks to recent science studies such as sociogenomics, I look at the molecular and genetic components of altruism discovered. Eusocial insects such as ants or honeybees are good model organisms in this field. In the human species, studies found a significant role of the hormones dopamine and vasopressin in prosocial behaviours. In any case, genetic research is still at its beginnings and more studies need to be conducted in the future.
... Altruistic behavior, in which individuals pay cost to benefit the rest of the population, can be considered a particular form of cooperation [35][36][37][38] . Recently, the ultimatum game has been used to examine fairness and altruistic behaviors 39-47 . ...
... Altruistic behavior, in which individuals pay cost to benefit the rest of the population, can be considered a particular form of cooperation [35][36][37][38] . Recently, the ultimatum game has been used to examine fairness and altruistic behaviors [39][40][41][42][43][44][45][46][47] . ...
The evolution of cooperation is a hot and challenging topic in the field of evolutionary game theory. Altruistic behavior, as a particular form of cooperation, has been widely studied by the ultimatum game but not by the dictator game, which provides a more elegant way to identify the altruistic component of behaviors. In this paper, the evolutionary dictator game is applied to model the real motivations of altruism. A degree-based regime is utilized to assess the impact of the assignation of roles on evolutionary outcome in populations of heterogeneous structure with two kinds of strategic updating mechanisms, which are based on Darwin's theory of evolution and punctuated equilibrium, respectively. The results show that the evolutionary outcome is affected by the role assignation and that this impact also depends on the strategic updating mechanisms, the function used to evaluate players' success, and the structure of populations.
... Indeed, altruism is certainly not found to be the general case in nature. Nevertheless, altruistic behaviors can be found in many social animals and, indeed, can be fundamental for some species to survive [7]. ...
We study a model for switching strategies in the Prisoner's Dilemma game on adaptive networks of player pairings that coevolve as players attempt to maximize their return. We use a node-based strategy model wherein each player follows one strategy at a time (cooperate or defect) across all of its neighbors, changing that strategy and possibly changing partners in response to local changes in the network of player pairing and in the strategies used by connected partners. We compare and contrast numerical simulations with existing pair approximation differential equations for describing this system, as well as more accurate equations developed here using the framework of approximate master equations. We explore the parameter space of the model, demonstrating the relatively high accuracy of the approximate master equations for describing the system observations made from simulations. We study two variations of this partner-switching model to investigate the system evolution, predict stationary states, and compare the total utilities and other qualitative differences between these two model variants.
... An increased replacement rate has a similar effect, as increasing r shortens the average number of plays that a pair engages in, and this again decreases the probability to face a kin strategy (mutated or not). Previously, a general theory for the evolution of cooperation has been proposed [42,43] that posits that positive assortment between a player's genotype and the opponent's phenotype is sufficient to promote cooperation, using arguments that ultimately recapitulate Queller's [44] extension of Hamilton's rule. ...
The observed cooperation on the level of genes, cells, tissues, and individuals has been the object of intense study by evolutionary biologists, mainly because cooperation often flourishes in biological systems in apparent contradiction to the selfish goal of survival inherent in Darwinian evolution. In order to resolve this paradox, evolutionary game theory has focused on the Prisoner's Dilemma (PD), which incorporates the essence of this conflict. Here, we encode strategies for the iterated Prisoner's Dilemma (IPD) in terms of conditional probabilities that represent the response of decision pathways given previous plays. We find that if these stochastic strategies are encoded as genes that undergo Darwinian evolution, the environmental conditions that the strategies are adapting to determine the fixed point of the evolutionary trajectory, which could be either cooperation or defection. A transition between cooperative and defective attractors occurs as a function of different parameters such a mutation rate, replacement rate, and memory, all of which affect a player's ability to predict an opponent's behavior.
... Note that the PG game is specifically characterized by the parameters N , r, and c (group size, efficiency and cost of the PG, respectively). We fix c=1 and r<N (this second condition defines producers/cooperators as strong altruists [29]) and also the conditions of the initial population (constituted by a common pool of k identical plastic agents in the P state; k is thus the maximal population size). The system is updated in a sequential way as follows (Supplement for further details): 1. ...
In the commons, communities whose growth depends on public goods, individuals often rely on surprisingly simple strategies, or heuristics, to decide whether to contribute to the common good (at risk of exploitation by free-riders). Although this appears a limitation, here we show how four heuristics lead to sustainable growth by exploiting specific environmental constraints. The two simplest ones --contribute permanently or switch stochastically between contributing or not-- are first shown to bring sustainability when the public good efficiently promotes growth. If efficiency declines and the commons is structured in small groups, the most effective strategy resides in contributing only when a majority of individuals are also contributors. In contrast, when group size becomes large, the most effective behavior follows a minimal-effort rule: contribute only when it is strictly necessary. Both plastic strategies are observed in natural systems what presents them as fundamental social motifs to successfully manage sustainability.
... Finally, altruism refers to a player's willingness to incur personal costs to benefit others, even when it conflicts with their self-interest [40]. It involves acting for the greater good, potentially leading to cooperative behavior that can influence outcomes in strategic interactions [10]. ...
Anonymous messaging and payments have gained momentum recently due to their impact on individuals, society, and the digital landscape. Fuzzy Message Detection (FMD) is a privacy-preserving protocol where an untrusted server performs message anonymously filtering for its clients. To prevent the server from linking the sender and the receiver, the latter can set how much cover traffic they should download along with genuine messages. This could cause unwanted messages to appear on the user's end, thereby creating a need to balance one's bandwidth cost with the desired level of unlinkability. Previous work showed that FMD is not viable with selfish users. In this paper, we model and analyze FMD using the tools of empirical game theory and show that the system needs at least a few altruistic users to operate properly. Utilizing real-world communication datasets, we characterize the emerging equilibria, quantify the impact of different types and levels of altruism, and assess the efficiency of potential outcomes versus socially optimal allocations. Moreover, taking a mechanism design approach, we show how the betweenness centrality (BC) measure can be utilized to achieve the social optimum.
... As for the -person games, see Eqs. (2) and (3), the binomial distribution is the usual choice to model the composition of the trait groups [48]. Although game theory, and in particular the -person prisoner's dilemma, has already proven useful in integrating elements (e.g., Hamilton's rule and the Price equation) of multilevel selection and inclusive fitness theories for the evolution of altruism [49], the connection between the replicator equation and Wilson's trait group framework seems to go unnoticed. It might be claimed that neither our model of game dynamics in casual groups, nor Wilson's trait group model, are models of group selection sensu stricto [50], which require birth and death processes at both the group and individual levels (see, e.g., [51][52][53][54]). ...
Understanding the conditions for maintaining cooperation in groups of unrelated individuals despite the presence of non-cooperative members is a major research topic in contemporary biological, sociological, and economic theory. The
N-person snowdrift game models the type of social dilemma where cooperative actions are costly, but there is a reward for performing them. We study this game in a scenario where players move between play groups following the casual group dynamics, where groups grow by recruiting isolates and shrink by losing individuals who then become isolates. This describes the size distribution of spontaneous human groups and also the formation of sleeping groups in monkeys. We consider three scenarios according to the probability of isolates joining a group. We find that for appropriate choices of the cost-benefit ratio of cooperation and the aggregation–disaggregation ratio in the formation of casual groups, free-riders can be completely eliminated from the population. If individuals are more attracted to large groups, we find that cooperators persist in the population even when the mean group size diverges. We also point out the remarkable similarity between the replicator equation approach to public goods games and the trait group formulation of structured demes.
... EGT is somewhat successful in modeling social phenomena due to interactions between individuals trying to maximize utility. The emergence of altruism in an n-player prisoner's dilemma using EGT is proposed by [88]. Authors suggest that utilizing an EGT approach has been shown to help understand the inherited similarities between weak and strong altruism. ...
We shall have a hard look at ethics and try to extract insights in the form of abstract properties that might become tools. We want to connect ethics to games, talk about the performance of ethics, introduce curiosity into the interplay between competing and coordinating in well-performing ethics, and offer a view of possible developments that could unify increasing aggregates of entities. All this is under a long shadow cast by computational complexity that is quite negative about games. This analysis is the first step toward finding modeling aspects that might be used in AI ethics for integrating modern AI systems into human society.
... 25 See, e.g., (Fletcher & Zwick, 2007;Gintis et al., 2003;Sánchez & Cuesta, 2005;Trivers, 1971). 26 See, e.g., (Alexander, 2007;Boehm, 1982;Harms & Skyrms, 2008;Skyrms, 2004Skyrms, , 1996. ...
Policy and guideline proposals for ethical artificial intelligence research have proliferated in recent years. These are supposed to guide the socially-responsible development of AI for a common good. However, there typically exist incentives for non-cooperation (i.e., non-adherence to such policies and guidelines); and, these proposals often lack effective mechanisms to enforce their own normative claims. The situation just described constitutes a social dilemma—namely, a situation where no one has an individual incentive to cooperate, though mutual cooperation would lead to the best outcome for all involved. In this paper, we use stochastic evolutionary game dynamics to model this social dilemma in the context of the ethical development of artificial intelligence. This formalism allows us to isolate variables that may be intervened upon, thus providing actionable suggestions for increased cooperation amongst numerous stakeholders in AI. Our results show how stochastic effects can help make cooperation viable in such a scenario. They suggest that coordination for a common good should be attempted in smaller groups in which the cost of cooperation is low, and the perceived risk of failure is high. This provides insight into the conditions under which we should expect such ethics proposals to be successful with regard to their scope, scale, and content.
... EGT is rather successful in modeling social phenomena due to interactions between individuals trying to maximize their utility. The emergence of altruism in an n-player prisoner's dilemma using EGT is proposed by (Fletcher & Zwick, 2007). Authors suggest that utilizing an EGT approach has shown to be useful in understanding the inherited similarities between weak and strong altruism. ...
We shall have a hard look at ethics and try to extract insights in the form of abstract properties that might become tools. We want to connect ethics to games, talk about the performance of ethics, introduce curiosity into the interplay between competing and coordinating in well-performing ethics, and offer a view of possible developments that could unify increasing aggregates of entities. All this is under a long shadow cast by computational complexity that is quite negative about games. This analysis is the first step toward finding modeling aspects that might be used in AI ethics for integrating modern AI systems into human society.
... Örgütsel vatandaşlık davranışının boyutlarından biri de özgeciliktir (Organ & Lingl, 1995). Ancak örgütsel vatandaşlık davranışı politik olarak ya da bir karşılık bekleyerek (sosyal mübadele kapsamında) de sergilenebildiği için tam bir özgecilik davranışından bahsetmek zordur (Fletcher & Zwick, 2007;Midlarsky & Suda, 1978). Özgeci bireyler diğerlerinin yararına davranmasının altında psikolojik ve ahlaki nedenler bulunmaktadır (Smith, 1995). ...
Amaç –Bu çalışmanın amacı, sağlık çalışanlarının örgütsel bağlılık algılarını değerlendirmek ve örgütsel bağlılığın çalışan performansı ve iş tatmini ile olan teorik ilişkisini test etmektir. Ayrıca bu ilişkide özgeciliğin düzenleyici rolü de araştırılmıştır.Yöntem –Sağlık alanında hizmet veren dört özel hastanede görev yapan 227 çalışandan kolayda örneklem yöntemiyle veri toplanmıştır. Çalışmada değişkenler arası ilişkiler ve etkileri korelasyon ve regresyon analizleri ile ortaya konulmuş, düzenleyici etki regresyon eğrisi ile ayrıca sınanmıştır.Bulgular –Elde edilen bulgulara göre, sağlık çalışanlarının örgütsel bağlılık algılarındaki artış, performanslarını ve iş tatminlerini arttırmaktadır. Bunun yanı sıra sağlık çalışanlarının özgeciliği örgütsel bağlılıkları ile performansları arasındaki ilişkide düzenleyici rol üstlenmektedir.Tartışma –Bu çalışma, bağlılık, çalışan performansı ve iş tatmini ilişkisinde özgeciliğin düzenleyici rolünü ortaya koymaya çalışmaktadır. Yazında sağlık çalışanları açısından söz konusu değişkenlerin hepsinin bir arada ele alındığı ve özgeciliğin düzenleyici etkisinin araştırıldığı bir çalışmaya rastlanamamıştır. Bu bağlamda çalışma sonuçlarının hem yazın hem de uygulayıcılar açısından olduğu değerlendirilmektedir.Çünkü sağlık kurumlarında verilen hizmetlerin hastalara etkin ve verimli bir şekilde sunulabilmesinde dikkate alınması gereken hususlardan birisi de sağlık çalışanlarının tutum ve davranışlarını etkileyen faktörlerdir. Çalışanların kurum içerisindeki algıları sundukları hizmeti doğrudan veya dolaylı olarak etkileyebilir.
... x a qui représente la proportion d'individus de phénotype a et x b , la proportion d'individus de phénotype b. L'évolution de la population est donnée par l'équation de réplication, qui consiste en l'équation différentielle suivante : [Fletcher andZwick, 2007, Gintis et al., 2003] ou les comportements moraux [Alexander, 2009, Boehm, 1982, constituent des situations évolutionnairement stables Smith [1982] 32 . Le comportement ne résulte pas de préférences au sens où l'entend la théorie du choix rationnel. ...
This Ph.D. dissertation aims at providing new conceptual and formal tools in order to model preference changes. To do so, I model a mechanism that I refer to as partial deliberation. Partial deliberation is based on the idea that individuals change their preference by becoming aware of new values. Indeed, their awareness allows them either to reject values they were adhering to or to adopt new values. By critically analysis of the literature on preference changes and on rational choice theory, the introduction emphasizes the main philosophical issues of partial deliberation. The first chapter justifies the five psychological hypotheses on which this mechanism relies and discusses their relation with rational choice theory. The second chapter axiomatically deals with partial deliberation and it formalizes two specific structures : a monotonic structure and partitional structure.Then, the third chapter models a situation of preference manipulation, in which a sender jointly chooses a project and a disclosure strategy in order to manipulate the preference of a receiver. With this model, I account for imperfect empathy and sequential disclosure of values.
... Refs. [373,376,358,374,317,88,158,177,346,90,153,348]. ...
Cooperative behavior, the costly provision of benefits to others, is common across all domains of life. This review article discusses cooperative behavior in the microbial world, mediated by the exchange of extracellular products called public goods. We focus on model species for which the production of a public good and the related growth disadvantage for the producing cells are well described. To unveil the biological and ecological factors promoting the emergence and stability of cooperative traits we take an interdisciplinary perspective and review insights gained from both mathematical models and well-controlled experimental model systems. Ecologically, we include crucial aspects of the microbial life cycle into our analysis and particularly consider population structures where an ensemble of local communities (sub populations) continuously emerge, grow, and disappear again. Biologically, we explicitly consider the synthesis and regulation of public good production. The discussion of the theoretical approaches includes general evolutionary concepts, population dynamics, and evolutionary game theory. As a specific but generic biological example we consider populations of Pseudomonas putida and its regulation and utilization of pyoverdines, iron scavenging molecules. The review closes with an overview on cooperation in spatially extended systems and also provides a critical assessment of the insights gained from the experimental and theoretical studies discussed. Current challenges and important new research opportunities are discussed, including the biochemical regulation of public goods, more realistic ecological scenarios resembling native environments, cell to cell signalling, and multi-species communities.
... Refs. [373,376,358,374,317,88,158,177,346,90,153,348]. ...
Cooperative behavior, the costly provision of benefits to others, is common across all domains of life. This review article discusses cooperative behavior in the microbial world, mediated by the exchange of extracellular products called public goods. We focus on model species for which the production of a public good and the related growth disadvantage for the producing cells are well described. To unveil the biological and ecological factors promoting the emergence and stability of cooperative traits we take an interdisciplinary perspective and review insights gained from both mathematical models and well-controlled experimental model systems. Ecologically, we include crucial aspects of the microbial life cycle into our analysis and particularly consider population structures where an ensemble of local communities (sub populations) continuously emerge, grow, and disappear again. Biologically, we explicitly consider the synthesis and regulation of public good production. The discussion of the theoretical approaches includes general evolutionary concepts, population dynamics, and evolutionary game theory. As a specific but generic biological example we consider populations of Pseudomonas putida and its regulation and utilization of pyoverdines, iron scavenging molecules. The review closes with an overview on cooperation in spatially extended systems and also provides a critical assessment of the insights gained from the experimental and theoretical studies discussed. Current challenges and important new research opportunities are discussed, including the biochemical regulation of public goods, more realistic ecological scenarios resembling native environments, cell to cell signalling, and multi-species communities.
... Several explanations have been given for such seemingly contradicting results using the methods of game theory. Including spatial structure in evolutionary games can lead to the evolution of altruism (e.g., Ohtsuki et al., 2006;Fletcher and Zwick, 2007). This, of course, is reflected in the present analysis, which also relies on spatial structure and differences among demes to achieve an advantage of altruists. ...
We model natural selection for or against an anti-parasite (or anti-predator) defense allele in a host (or prey) population that is structured into many demes. The defense behavior has a fitness cost for the actor compared to non defenders (“cheaters”) in the same deme and locally reduces parasite growth rates. Hutzenthaler et al. (2022) have analytically derived a criterion for fixation or extinction of defenders in the limit of large populations, many demes, weak selection and slow migration. Here, we use both individual-based and diffusion-based simulation approaches to analyze related models. We find that the criterion still leads to accurate predictions for settings with finitely many demes and with various migration patterns.
A key mechanism of providing a benefit of the defense trait is genetic drift due to randomness of reproduction and death events leading to between-deme differences in defense allele frequencies and host population sizes. We discuss an inclusive-fitness interpretation of this mechanism and present in-silico evidence that under these conditions a defense trait can be altruistic and still spread in a structured population.
... Daha sonraları ise insan davranışının temel güdüsü olarak bireyin kendi çıkarını gözeteceğini savunan egoizmin karşıt görüşü olarak normatif ve psikolojik özgecilik görüşü ortaya atılmıştır (Williamson, 1989). Özgeci davranışı sosyal mübadele kuramı ile açıklamaya çalışan yazarlara (örneğin Milinski, Semmann, & Krambeck, 2002), mübadele ilişkisinde karşı taraftan bir bek-lenti olduğu için bunun özgeci davranış olarak değerlendirilemeyeceği konusunda eleştiriler getirilmiştir (Fletcher & Zick, 2007). "Mahkûmun İkilemi" ve "Diktatör Oyunu" gibi deneysel çalışmalar, bireylerin aldıkları kararlarda sadece kendi çıkarlarını maksimize etmeye çalışmadıklarını, kendisine bir maliyeti olsa bile karşı tarafın yararına davranış sergilediklerini göstermişlerdir (Levitt & List, 2007). ...
Çalışan performansını artırmak, günümüz rekabet ortamında, örgütlerin önemli sorunları arasında yer almaktadır. Çalışanların performansını artırırken maliyetleri artırmamak ve çalışan motivasyonunu düşürmemek örgütsel etkinlik için gerekliliktir. Bu kapsamda, bir prososyal davranış olarak diğerlerin yararına gösterilen davranışlar, diğer bir ifadeyle özgeci davranışlar, maliyetleri artırmadan çalışan performansını artırabilen yöntemlerden biridir. Çalışmada özgeci davranışların çalışan performansı üzerindeki etkisi incelenmiştir. Kesitsel yöntem kullanılarak kolayda örnekleme ile bir kamu kurumunda çalışan 103 kişiden toplanan verilerin analizi sonucu araştırma hipotezi test edilmiştir. Verileri toplamak için Rushton ve diğerleri (1981) tarafından geliştirilen "özgeci davranış ölçeği" ve Kirkman ve Rosen (1999) tarafından geliştirilen "iş performans ölçeği" kullanılmıştır. Hipotezin testi korelasyon ve regresyon analiziyle yapılmıştır. Özgeci davranışlar ve çalışan performansı arasında pozitif ve anlamlı korelasyon vardır (r=0,414, p<0,001). Sonuçlara göre, özgeci davranışlar çalışanların iş performansını pozitif ve anlamlı bir şekilde etkilemektedir.
... Plants typically interact competitively with their nearest neighbours (Milbau et al. 2007). Population structure, i.e., local groups within the larger population, creates an opportunity for multilevel selection on group vs. individual fitness (Fletcher & Zwick 2007). Relatedness among neighbours, i.e., whether neighbours of same species are relatives or unrelated strangers, provides the opportunity for kin selection on altruism (Hamilton 1964). ...
Intraspecific competition among crop plants is undesirable. Less competitive crops are predicted to increase yield and decrease the need for added resources.
Wild plants demonstrate the ability to recognize kin and potentially help their relatives by reducing their competitive behaviours, a form of altruism. Altruism can also evolve through multilevel selection. Are these processes relevant to sustainable agriculture?
Crops do grow predictably with kin. However, their evolution is more strongly dictated by artificial selection (crop breeding), which incorporates individual and group selection, making multilevel selection more relevant than kin selection in favouring altruism. While current crop breeding protocols attempt to target the reduction of competitive traits, early mass selection may have the opposite effect.
We predict that kin recognition itself is not relevant to crops, because of the consistently high relatedness within crop stands. Nonetheless, crops have shown cultivar and kin recognition. We argue that these responses cannot be assumed to demonstrate altruism, as current breeding practices offer little opportunity for kin selection.
Synthesis . There is the opportunity to favour altruism through artificial breeding. Here we suggest how crop breeding protocols could be changed to favour cooperation by increasing group selection during early breeding.
... Indeed, altruism is certainly not found to be the general case in nature. Nevertheless, altruistic behaviors can be found in many social animals and, indeed, can be fundamental for some species to survive [7]. ...
We study a model for switching strategies in the Prisoner's Dilemma game on adaptive networks of player pairings that coevolve as players attempt to maximize their return. We use a node-based strategy model with each player following one strategy (cooperate or defect) at a time with all of its neighbors. We improve on the existing pair approximation (PA) model for this system by using approximate master equations (AMEs). We explore the parameter space demonstrating the accuracy of the approximation as compared with simulations. We study two variations of this partner-switching model to investigate the evolution, predict stationary states, and compare the total utilities and other qualitative differences between these two variants.
... The low dimensionality of such models is useful when fitting historical and archaeological data, which are seldom rich enough to fit complex models. Game theoretical approaches have been traditionally used for studying adaptive processes when strategic interactions are important (Smith 1982), and can be also potentially be adapted to explore multilevel dynamics (Fletcher and Zwick 2007). Statistical and stochastic models are increasingly popular ways to introduce heterogeneity into a population-based system. ...
Cultural adaptation has become central in the context of accelerated global change with authors increasingly acknowledging the importance of understanding multilevel processes that operate as adaptation takes place. We explore the importance of multilevel processes in explaining cultural adaptation by describing how processes leading to cultural (mis)adaptation are linked through a complex nested hierarchy, where the lower levels combine into new units with new organizations, functions, and emergent properties or collective behaviours. After a brief review of the concept of "cultural adaptation" from the perspective of cultural evolutionary theory and resilience theory, the core of the paper is constructed around the exploration of multilevel processes occurring at the temporal, spatial, social and political scales. We do so by examining small-scale societies' case studies. In each section, we discuss the importance of the selected scale for understanding cultural adaptation and then present an example that illustrates how multilevel processes in the selected scale help explain observed patterns in the cultural adaptive process. We end the paper discussing the potential of modelling and computer simulation for studying multilevel processes in cultural adaptation.
... We find it instructive to consider the deme-level selection effect also from the perspective of kin selection (Hamilton, 1963(Hamilton, , 1964aWade, 1980;Queller, 1991). There is an ongoing debate about whether multilevel selection is just a special case of kin selection, whether both approaches are equivalent, or whether there are biologically relevant scenarios in which a multilevel selection approach is more fruitful than an inclusive-fitness analysis (Fletcher & Zwick, 2007;Gardner et al., 2007;Nowak et al., 2010;Traulsen, 2010;Abbot et al., 2011;Lion et al., 2011;Marshall, 2011;Rousset & Lion, 2011;van Veelen et al., 2014;Gardner, 2015). Gardner et al. (2011) and Birch & Okasha (2015) point out that the answers to these questions depend on the precise definitions of relatedness, cost and benefit in Hamilton's rule. ...
... The later (y) refers to an individual's commitment to the success of the group as a whole. The model highlights the interplay between individual and group effects that is characteristic of modern views of social evolution (Bergstrom, 2002;Fletcher and Zwick, 2007;Henrich, 2004). ...
Purpose
– The purpose of this study is to fill a gap in evolutionary theorizing in the field of information systems. Evolutionary theorizing has recently been added as a useful tool to the research repertoire of information systems investigators. However, the literature on evolutionary theorizing and related empirical research lacks a clear framework that explicitly shows how information systems researchers can go, step-by-step, from a generic model of the evolution of traits in our ancestral past to a more specific model depicting the effects of technology facilitation of those traits among modern humans. The purpose of this study is to fill this gap through a framework composed of six stages.
Design/methodology/approach
– To discuss and illustrate the framework, the authors develop an easy-to-understand generic path model explicitly depicting relationships among variables related to events that occurred in our evolutionary past. We then incrementally adapt this generic path model, eventually arriving at a focused path model depicting causal relationships among social networking site use, job satisfaction, organizational commitment and job performance. In doing so, the authors also develop a theoretical model about how social networking site use can affect job performance, where a positive total effect is predicted via positive intermediate effects on job satisfaction and organizational commitment.
Findings
– To discuss the final stage in the framework, the authors present an illustrative example where the focused path model is tested based on a study of the effect of Facebook use on job performance among 178 working professionals across the USA. This illustrative example provides general support for the theoretical model.
Research limitations/implications
– The counterintuitive hypothesis that Facebook use is associated with increased job performance is supported.
Practical implications
– Social networking site use by organizational employees is likely to be associated with improved job performance.
Originality/value
– This study provides a clear framework that shows how researchers can go from a generic evolutionary path model in our ancestral past to a more specific model comprising technology effects in modern humans.
... This metric is based on Hamilton's rule (Hamilton 1964). Similar versions have been used by Fletcher and Zwick (2007) and Pepper and Smuts (2002). Here, the 'assortment ratio' r is defined as: ...
Uncertainty and risk are key features of many social dilemmas, where individual decisions are often made with imperfect knowledge and variance in outcomes. In this paper, we investigate the evolutionary dynamics of the well-known public goods game using a recently introduced modelling framework encapsulating risk-sensitive assortment. Here, the population of mobile agents playing the game is divided into fixed-sized interaction groups. Individuals are defined by a single genetic trait—a risk sensitivity trait—that guides their decision-making. This trait is mapped to a continuous range of investment levels and also provides a mechanism to guide mobility (migration) decisions. Detailed computational simulation experiments confirm the relationship between risk orientation, decision-making and mobility in the game. As the size of each group increases, assortment levels tend to decrease and risk-averse individuals tend to dominate the population. However, in many scenarios, there was high variance in the proportion of ‘cooperators’ both in groups and between different groups, suggesting that risk-seeking behaviour is an emergent property of mobility induced positive assortment.
... We find it instructive to consider the deme-level selection effect also from the perspective of kin selection (Hamilton, 1963(Hamilton, , 1964aWade, 1980;Queller, 1991). There is an ongoing debate about whether multilevel selection is just a special case of kin selection, whether both approaches are equivalent, or whether there are biologically relevant scenarios in which a multi-level selection approach is more fruitful than an inclusive-fitness analysis (Fletcher and Zwick, 2007;Gardner et al., 2007;Traulsen, 2010;Marshall, 2011;Nowak et al., 2010;Rousset and Lion, 2011;Abbot et al., 2011;Lion et al., 2011;van Veelen et al., 2014;Gardner, 2015). Gardner et al. (2011) and Birch and Okasha (2015) point out that the answers to these questions depend on the precise definitions of relatedness, cost and benefit in Hamilton's rule. ...
How can anti-parasite defense traits evolve even if they do not directly benefit their carriers? An example of such an indirect defense is rebellion of enslaved Temnothorax longispinosus ant workers against their social parasite Temnothorax americanus, a slavemaking ant. Ant slaves have been observed to kill their oppressors' offspring, a behavior from which the sterile slaves cannot profit directly. Parasite brood killing could however reduce raiding pressure on related host colonies nearby. We analyze with extensive computer simulations for the Temnothorax slavemaker system under what conditions a hypothetical rebel allele could invade a host population, and in particular how host-parasite dynamics and population structure influence the rebel allele's success. Exploring a wide range of model parameters, we only found a small number of parameter combinations for which kin selection or multi-level selection could allow a slave rebellion allele to spread in the host population. Furthermore, we did not detect any cases in which the reduction of raiding pressure in the close vicinity of the slavemaker nest would substantially contribute to the inclusive fitness of rebels. This suggests that slave rebellion is not costly and perhaps a side-effect of some other beneficial trait. In some of our simulations, however, even a costly rebellion allele could spread in the population. This was possible when host-parasite interactions led to a metapopulation dynamic with frequent local extinctions and recolonizations of demes by the offspring of few immigrants. This article is protected by copyright. All rights reserved.
... In the literature, the terms cooperation and altruism are often found side by side. Both phenomena have been the focus of a particular attention from many research elds, including Game Theory [Fletcher and Zwick, 2007] and Biology [Piliavin and Charng, 1990]. Both cooperative acts are performed either thanks to a social act (e.g. ...
Cette thèse décrit une partie du travail effectué dans le cadre du projet européen Symbrion 1 . Ce projet vise à la réalisation de tâches complexes nécessitant la coopération de multiples robots dans un cadre de robotique en essaim (au moins 100 robots opérant ensemble). De multiples problèmes sont étudiés par le projet dont : l’auto-assemblage de robots en structures complexes et l’auto-organisation d’un grand nombre de robots afin de réaliser une tâche commune. Le principal sujet porte sur les mécanismes d’auto-adaptation pour la robotique modulaire et en essaim, avec un intérêt pour des capacités de forte coordination et de coopération à l’échelle de l’essaim.Les difficultés rencontrées dans la réalisation de ce projet sont dues à l’utilisation de robots dans des environnements ouverts restant inconnus jusqu’à la phase de déploiement. Puisque les conditions d’opérations ne peuvent être prédites à l’avance, des algorithmes d’apprentissage en ligne doivent être utilisés pour élaborer les comportements utilisés. Lorsqu’un grand nombre de robots sont utilisés, plusieurs considérations doivent être prise en compte : capacité de communication réduite, faible mémoire, faible capacité de calcul. Par conséquent les algorithmes d’apprentissage en ligne doivent être distribués à travers l’essaim.De multiples approches ont déjà été proposées pour faire face aux problèmes posés par l’apprentissage en ligne décentralisé de comportements robotiques, parmi lesquels la robotique probabiliste, l’apprentissage par renforcement, et la robotique évolutionnaire. Cependant, le problème abordé dans le cadre de cette thèse se caractérise par le fait que l’on considère un groupe de robots (en lieu et place d’un seul et unique robot). De plus, dû à la nature ouverte de l’environnement, il n’est pas possible de supposer que l’ingénieur humain ait les connaissances nécessaires pour définir les éléments indispensables aux processus d’apprentissage.Assurer l’intégrité de l’essaim est placé en tant que premier élément d’une feuille de route visant à définir un ensemble d’étapes nécessaires à la réalisation d’une tâche par un groupe de robot dans un environnement ouvert :– Étape 1 : Assurer l’intégrité de l’essaim.– Étape 2 : Maintenir les robots disponibles en tant que service à l’utilisateur.– Étape 3 : Réaliser la tâche définie par l’utilisateur.Dans le cadre de cette thèse nous travaillons à la réalisation de l’étape 1 de cette feuille de route, et assumons l’hypothèse de travail suivante :Hypothèse de travail : Dans un cadre de robotique collective en environnement ouvert, la réalisation d’une tâche définie par l’utilisateur implique tout d’abord un comportement auto-adaptatif.Le sujet de cette thèse est la réalisation de solutions algorithmiques décentralisées pouvant garantir l’in- tégrité d’un essaim de robots en environnement ouvert lorsque un système robotique collectif utilise une communication locale. La principale difficulté à sa résolution est le besoin de prendre en compte l’envi- ronnement. En effet, en fonction de l’environnement courant, les robots peuvent avoir à démontrer une grande variété de comportements à l’échelle globale comme la coopération, la spécialisation, l’altruisme, ou la division du travail.Dans cette thèse nous introduisons et définissons le problème de l’Adaptation Evolutionnaire Distribuée Guidée par l’Environnement. Nous proposons un algorithme pour résoudre ce problem. Cet algorithme a été validé aussi bien en simulation que sur des robots réels. Il a été utilisé pour étudier le problème de l’auto-adaptation dans les environnements suivants :– Environnement où l’émergence de consensus comportementaux est nécessaire.– Environnements où la robustesse face à des changements environnementaux est nécessaires.– Environnements où des comportements altruistes sont nécessaires.
... Olson (1965, p. 60) posits that, -people are sometimes motivated by a desire to win prestige, respect, friendship, and other social and psychological objectives,‖ and, as Becker An exception to neo-classical theory that has gained recognition from economists is the study of simple altruism (Rabin, 1993). Altruism, where an individual derives personal utility from the combination of their own consumption and the consumption (or utility) of others (Shang & Croson, 2009), is surprisingly common amongst unrelated people even when no reciprocation is likely or forthcoming (Fletcher & Zwick, 2007). The theory relies on individuals gaining a private benefit from unselfishly placing the interests of the group ahead of their own, in an attempt to provide philanthropic benefit to society. ...
... In such scenarios, cooperation might prevail due to the structure of the population [5,1,3,7,8,9]; this idea has been studied both theoretically and experimentally in the context of kin-, group-and multilevel selection [10,1,11,12,13,14,15,16,17,18,19,20,6,21,22,23,7,24]. If cooperators more likely interact with other cooperators (positive assortment), they keep most of their benefit for themselves and are less exploited by non-cooperators. ...
Cooperative behaviour is widespread in nature, even though cooperating individuals always run the risk of being exploited by free-riders. Population structure effectively promotes cooperation given that a threshold in the level of cooperation was already reached. However, the question how cooperation can emerge from a single mutant, which cannot rely on a benefit provided by other cooperators, is still puzzling. Here, we investigate this question for a well-defined but generic situation based on typical life cycles of microbial populations where individuals regularly form new colonies followed by growth phases. We analyse two evolutionary mechanisms favouring cooperative behaviour and study their strength depending on the inoculation size and the length of a life cycle. In particular, we find that population bottlenecks followed by exponential growth phases strongly increase the survival and fixation probabilities of a single cooperator in a free-riding population.
© 2015 The Author(s) Published by the Royal Society. All rights reserved.
... For animals, although it is hard to determine whether they behave rationally, we expect those irrational players have already been excluded by natural selection because irrational strategy, even if sometimes may yields a better payoff, will finally be excluded in evolution as seen in the prisoner's dilemma (Axelrod, 2006). By using n-player prisoner's dilemma, Game Theory has been applied to explain altruism (Fletcher and Zwick, 2007). These methods are relatively complicated and we could use DP to present an intuitive explanation of how altruism possibly arises and maintains in the resource competition: for some fast-growing non-aggressive players, their development completes before they could deplete all resources. ...
Resource competition is commonly occurred in animal populations and studied intensively by researchers. Previous studies have applied game theoretic model by finding Nash equilibrium to investigate this phenomenon. However computation of the Nash equilibrium requires an understanding of the payoff matrix that allocates the rewards received by players when they adopt each of the strategies in the game. In our study we present a dynamic programming implemented framework to compute 2 × 2 intraspecific finite resource allocation game's payoff matrix explicitly. We assume that two distinct types of individuals, aggressive and non-aggressive, are in the population. Then we divide the entire animal development period into three different stages: initialization, quasilinear growth and termination. Each stage for each type of players is specified with their own development coefficient, which determines how resource consumption could convert into strength as reward. Each player has equal and finite resource at the beginning of their development and fights against other players in the population to maximize its own potential reward. Based on these assumptions it is reasonable to use backward induction dynamic programming to compute payoff matrix. We present numerical examples for three different types of aggressive individuals and compute the payoff matrices correspondingly. Then we use the derived payoff matrices to determine the Nash equilibrium and Evolutionary Stable Strategy. Our research provide a framework for future quantitative studies on animal resource competition problems and could be expanded to n-players interspecific stochastic asymmetric resource allocation problem by changing some settings of dynamic programming formulation.
... The Price Equation has over the years become one of the most widely used algebraic formulations in evolutionary theorizing addressing a range of phenomena, from the evolution of morphological traits in various animals to the evolution of behavioral traits in humans (FLETCHER and ZWICK 2007;FRANK 1995FRANK , 1997GRAFEN 2002GRAFEN , 2006HENRICH 2004;MCELREATH and BOYD 2007;PAGE and NOWAK 2002; VAN VEELEN 2005). ...
Sexually reproducing organisms often rely on various traits to judge the attractiveness of potential mates. Many mate choice preferences and traits have evolved through selection by those organisms' ancestors, with traits having been either costly (detrimental to survival) or non-costly in the environment of their evolutionary adaptation. A general mathematical analysis of the evolution of traits used in mate choice is presented. The analysis builds on a combination of Price's covariance equation and Wright's method of path analysis, and includes a set of Monte Carlo simulations. The usefulness of the mathematical analysis is demonstrated through the de-velopment of a small but important set of hypotheses and implications for the human species: (1) costly traits used in mate choice by humans should be generally less common and more attractive to the other sex than non-costly traits; (2) costly traits should be disproportionately less common in human females than in males; and (3) some harmful human mental disorders, such as schizo-phrenia, may have co-evolved as costs of attractive mental traits. It is also shown that similar analyses can be easily employed by evolutionary psychologists to theorize about the evolution of complex mate choice traits, and to test the resulting theories with modern humans through the method of path analysis.
Imitation based on fitness comparison has long been a representative strategy updating method in evolutionary game theory, with the pursuit of profit maximization at its core. However, the method fails when obtaining other agents’ income information is inaccessible or prohibitively expensive. As an alternative, reinforcement learning has been frequently used to alleviate this problem, yet it rarely achieves socially optimal outcomes. To fill this gap, this study proposes a self-regarding Q-learning with conformity effect and investigates its impact on the evolution of cooperation in a spatial Prisoner’s Dilemma Game. The instant reward of Q-learning is re-scaled following the logic that the more popular the strategy, the higher the re-scaled reward. The results reveal that reinforcement learning can alleviate social dilemmas in a way that prevents both sides of a game from freezing in a dilemma of mutual defection, thereby facilitating the coexistence of cooperation and defection. Depending on the dilemma strength, intriguingly, conformity has a two-sided effect on the evolution of cooperation. For lower b-values it promotes cooperation whereas for higher b-values it hinders cooperation. The reasons behind these phenomena are analyzed and the simulation results are shown to be consistent with the theoretical analysis.
When individuals or companies are unable to meet their financial obligations, they may undergo the process of bankruptcy and go out of business. At the same time, new companies may arise. In this work, we propose a coevolutionary game model incorporated with bankruptcy. In the model, each agent represents a company. Two factors, accumulated payoff and age, are taken into account to determine its bankrupt probability. We assume two possible bankrupt mechanisms, procedural bankruptcy and age-dependent bankruptcy. Through numerical simulations, we show that the bankruptcy can effectively promote cooperation. Moreover, we find the non-monotonic behavior of the cooperation level with the increase of noise intensity in procedural bankruptcy. By investigating the strategy patterns and the distributions of the bankruptcy probabilities for cooperators and defectors, we provide explanations for the promotion of cooperation and the optimization of the cooperation level. This work highlights the positive effects of bankruptcy mechanism on cooperation in the real business world.
Özgeci davranışlar, prososyal bir davranış olarak çıkar gözetmeden diğerlerinin yararına gösterilmektedir. Özgeci davranışların sosyal yaşama olduğu kadar örgütsel yaşama da katkıları bulunmaktadır. Özgeciliği örgütsel ortamlarda hangi unsurların etkilediğinin belirlenmesi örgütsel etkinlik için önemlidir. Bu etkinliğin sağlanmasındaki bir diğer husus da örgüt içerisindeki istismarcı yönetim algılarıdır. Çalışanlar aktif yaşamlarının büyük bir kısmının geçtiği işyerinde yöneticinin kaba ve istenmeyen söz ve davranışlarıyla karşılaşabilmektedir. Bu çalışanların stresini artırmakta, olumsuz iş tutum ve davranışlarına yol açabilmektedir. İstismarcı yönetimin adaletsizlik, aykırı iş davranışı, iş tatminsizliği, iş-aile çatışması ile pozitif ilişkisi söz konusuyken, iş performansı, örgütsel bağlılık ve örgütsel destek algılarıyla negatif ilişkisi mevcuttur. Psikolojik sözleşme veya psikolojik sözleşme ihlali yönetim ile çalışanlar arasındaki ilişkilerin dengesini değiştirebilmektedir. Bu araştırmada; istismarcı yönetim algısı ile özgeci davranış arasındaki ilişki ve bu ilişkide psikolojik sözleşme ihlali algısının düzenleyici rolü incelenmiştir. Araştırma verileri imalat sektöründe faaliyet gösteren beş farklı firmada çalışan 294 kişiden kolayda örnekleme yöntemiyle toplanmıştır. Hipotez testi için korelasyon ve regresyon analizi yapılmıştır. Sonuçlara göre istismarcı yönetimin özgeciliği negatif ve anlamlı bir şekilde etkilediği görülmektedir. İstismarcı yönetim algısı çalışan özgeciliği üzerindeki negatif değişimin %24'ünü açıklamaktadır. Ayrıca psikolojik sözleşme ihlali algısı istismarcı yönetim ile özgecilik arasındaki negatif ilişkiyi artırmaktadır. Bulgular istismarcı yönetim algısının azalan özgeci davranışlar ile ilişkili olduğu yönündedir ve çalışanların psikolojik sözleşme ihlal algılarının yüksek olması istismarcı yönetimin özgecilik üzerindeki negatif etkisini artırmaktadır.
Araştırmanın temel amacı Fauville vd.’nin (2021) geliştirdiği Zoom Exhaustion & Fatigue Scale isimli ölçüm aracının Türk kültüründe geçerlik ve güvenirliğini sağlamaktır. Araştırmanın evrenini Tokat Gaziosmanpaşa Üniversitesi’nde görevli akademisyenler oluşturmaktadır. Araştırmada zaman ve maliyet kısıtları nedeniyle kolayda örnekleme yöntemi tercih edilmiştir. Araştırma kapsamında Türkçeİngilizce çeviri ile ters çeviri işlemleri tamamlandıktan ve madde toplam korelasyonları incelendikten (.55 ile .88 arasında) sonra ifadeleri son haline getirilen ölçek, örnekleme elektronik ortamda ulaştırılmıştır. Gerekli analiz varsayımlarını karşılayan 62 katılımcıya ilişkin verilerle ileri analizler gerçekleştirilmiştir. Ölçeğin geçerleme sürecinde verilere uygulanan Doğrulayıcı Faktör Analizi sonucu, orijinaline uygun şekilde 15 ifade (en düşük madde faktör yükü .62) ve 5 alt boyut ile yapı geçerliği sağlanmıştır. İç tutarlılık katsayısı 5 alt boyut için .82 ile .94 arasında değişim göstermiştir. İlgili katsayı ölçeğin tamamı için .95 şeklinde hesaplanmıştır. Bulgulardan hareketle ölçeğin Türk kültürü için geçerli ve güvenilir bir ölçüm aracı olduğu tespit edilmiştir.
Çalışmanın temel amacı banka personellerinin nepotizm algılarını ölçmek ve iş yerindeki kişiler arası çatışma düzeylerine etkisini tespit ederek, ücret tatmininin bu etkileşimdeki düzenleyici rolünü belirlemektir. Nepotizm, kurumlarda adaleti algısını ortadan kaldıracak şekilde kullanılabilmektedir. Adaletin olmadığı kurumlarda da çatışmalar kaçınılmazdır. Bireyler bazı durumlarda kurum içerisindeki bu olumsuzlukları göz ardı etmektedirler. Kazanılan ücretin bireyleri tatmin edecek düzeyde dolgun oluşu veya tatminsizlik yaratacak şekilde düşük oluşu olumsuzluklara olan bakış açılarını değiştirebilmektedir. Performansa dayalı ücretlendirmenin yoğun olduğu bankacılık sektöründe kazanılan ücretin bu denklemde daha fazla rolü olduğu düşünülmektedir. Çalışma kapsamında banka personellerine online olarak 315 anket gönderilmiştir. Eldeki verilerin analizler için gerekli koşulları sağladığı tespit edilmiştir. Anket formunda kullanılan ölçeklerin geçerlilik ve güvenilirlik analizleri yapılmıştır. Sonraki aşamada değişkenler arasındaki ilişkilerin tespiti için korelasyon analizi yapılmış; hipotezlerin test edilmesi amacıyla da regresyon ve düzenleyici etki analizi gerçekleştirilmiştir. Analizler sonucunda nepotizmin iş yerindeki kişiler arası çatışmayı pozitif etkilediği ve ücret tatminin düşük düzeyde olduğu durumlarda bu etkileşimin arttığı tespit edilmiştir.
Policy and guideline proposals for ethical artificial-intelligence research have proliferated in recent years. These are supposed to guide the socially-responsible development of AI for the common good. However, there typically exist incentives for non-cooperation (i.e., non-adherence to such policies and guidelines); and, these proposals often lack effective mechanisms to enforce their own normative claims. The situation just described constitutes a social dilemma---namely, a situation where no one has an individual incentive to cooperate, though mutual cooperation would lead to the best outcome for all involved. In this paper, we use stochastic evolutionary game dynamics to model this social dilemma in the context of the ethical development of artificial intelligence. This formalism allows us to isolate variables that may be intervened upon, thus providing actionable suggestions for increased cooperation amongst numerous stakeholders in AI. Our results show how stochastic effects can help make cooperation viable in such a scenario. They suggest that coordination for a common good should be attempted in smaller groups in which the cost for cooperation is low, and the perceived risk of failure is high. This provides insight into the conditions under which we should expect such ethics proposals to be successful with regard to their scope, scale, and content.
The emergence of cooperation still remains a fundamental conundrum in the social and behavior sciences. We introduce a new mechanism, deposit mechanism, into theoretical model to explore how this mechanism promotes cooperation in a well-mixed population. Firstly, we extend the common binary-strategy combination of cooperation and defection in public good game by adding a third strategy, namely, deposit cooperation. The players with deposit cooperation strategy pay a deposit in advance to obtain the benefits of public good at a lower contributions compared with the players with cooperation strategy, when the provision of public good is successful. Then, we explore the evolution of cooperation in the public good game with deposit by means of the replicator dynamics. Theoretical computations and stimulations show that the deposit mechanism can promote cooperation in a well-mixed population, and the numbers of equilibrium point are determined by variables of public good game. On the one hand, when the coexistence of cooperators and defectors is the stable equilibrium point in the evolutionary system, increasing the threshold of public good and adopting the weak altruism way for share benefits can enhance the level of cooperation in the population. On the other hand, if the coexistence of deposit cooperators and defectors is the stable equilibrium point, it is effective to promote the deposit cooperation by lowering the values of discount and deposit, and raising the threshold of public good.
Bu çalışmanın amacı evrimsel biyoloji ve ekonomi arasında çeşitli analojiler kurarak iktisadi problemleri çok fazla girilmeyen bir bakış açısı ile açıklamaya çalışmaktır. Bernard Mandeville (1988 [1714]) Adam Smith’in düşüncelerini de etkileyen “Arıların Masalı” adlı çalışmasında toplum hayatını ve ekonomiyi arı kovanı ve toplum hayatı arasında analoji kurarak analiz etmiştir. Bu çalışmada ise iktisadi problemler, insan toplumu ile karınca kolonisi arasında kurulan analojiler yardımıyla analiz edilmektedir. Karınca kolonilerindeki “kendiliğinden düzen” ve “sosyal organizasyon” incelenmekte ayrıca insan toplumu ile benzerlikleri tartışılmaktadır. Sonuç olarak karıncaların bireyden sosyal organizasyonlara doğru evriminin, insan toplumu ve iktisadi olaylar hakkında da fikirler sağladığı görülmektedir.
In order to fully understand the interaction between selfish and non-selfish actors, social scientists need rigorous formal models of other-regarding preferences. While the current models clearly present progress relative to the self-interest approach, the evidence also makes it clear that further theoretical progress is warranted. There is ample opportunity for improving our understanding of other-regarding behavior. This paper develops a theory of economic altruism entirely compatible with self-interest utility maximization by rational individuals. Sympathy arises when someone is interested in improving somebody else’s condition, and this will also enhance the utility of the one who acts. Construed in that way, sympathetic behavior is essentially self-interested behavior. A question addressed in this paper is whether a sympathetic population of individuals will exert their income-producing labor differently than a population of egoistic individuals. Two parameters suffice to characterize the altruistic conduct of an individual: a parameter governing the individual’s ranking in a social hierarchy and a parameter determining the sensitivity of an individual’s sympathy for others at different social ranks. The main testable implication of the theory is that in a large population, where each individual has a concave utility function embodying sympathy, the altruistic behavior of any specific individual is determined by his rank in the social hierarchy. A second implication is that in a horizontal social hierarchy, the most altruistic people in the population are those in the middle of it.
Models of social evolution and the evolution of helping have been classified in numerous ways. Two categorical differences have, however, escaped attention in the field. Models tend not to justify why they use a particular assumption structure about who helps whom: a large number of authors model peer- to-peer cooperation of essentially identical individuals, probably for reasons of mathematical convenience; others are inspired by particular cooperatively breeding species, and tend to assume unidirectional help where subordinates help a dominant breed more efficiently. Choices regarding what the help achieves (i.e. which life-history trait of the helped individual is improved) are similarly made without much comment: fecundity benefits are much more commonly modelled than survival enhancements, despite evidence that these may interact when the helped individual can perform life-history reallocations (load-lightening and related phenomena). We review our current theoretical understanding of effects revealed when explicitly asking ‘who helps whom to achieve what’, from models of mutual aid in partnerships to the very few models that explicitly contrast the strength of selection to help enhance another individual’s fecundity or survival. As a result of idiosyncratic modelling choices in contemporary literature, including the varying degree to which demographic consequences are made explicit, there is surprisingly little agreement on what types of help are predicted to evolve most easily. We outline promising future directions to fill this gap. © 2016 The Author(s) Published by the Royal Society. All rights reserved.
We develop a conceptual framework that integrates concepts from evolutionary (game) theory and from cultural anthropology to study how cooperation emerges and persists within organizational contexts. In particular, we argue the case for three rules that govern the evolution of cooperation—kinship selection, direct reciprocity, and indirect reciprocity. We apply these rules to a cooperative arrangement that displays particularly interesting features as regards its entrepreneurial members’ tendencies towards choosing cooperative vs. defective, or “free-riding”, behavior: to the franchise form of organization. We further argue that social learning and cultural transmission mechanisms support these three rules of cooperation, so that cooperation can evolve and remain stable even in noisy and large group environments. The model helps organizations understand factors that affect cooperative tendencies among its network members, and provides direction on how to foster, promote, and fine-tune a cooperative climate in the network—initially, as well as in the long run. Accordingly, we develop specific propositions concerning the evolution of inter-firm cooperation within the franchised type of business.
To study the interactions and learning effect between players, this paper constructs two evolutionary game dynamic systems. One is with time delay, the other is without time delay. The paper analyzes the stabilities of equilibrium points in two evolutionary game systems on theory. We find that the stabilities of the 5 equilibrium points are different though two evolutionary game systems have the same equilibrium points. Though time delay has no impact on the situation of the final stable state, it may change the speed of system convergence to the stable points. The numerical simulations of this paper have verified that time delay and initial conditions have influence on the speed of convergence. So the conclusions of this paper mean that players will make more reasonable decisions if they make full use of the present and pass information in the evolutionary game.
This paper explores the following question: how a fixed-size population of autonomous agents (such as a swarm of robotic agents) may evolve altruistic behaviors during open-ended evolution. In particular, we focus on a situation where the tragedy of commons can possibly occur: a situation where individuals must display altruistic behaviors in order for the whole population to avoid extinction. Our approach considers a sub-individual framework, defined at the level of genomes rather than agents, in order to provide an efficient algorith-mic solution for the emergent of coordination among the pop-ulation. Experiments show that the proposed evolutionary adaptation algorithm favors the emergence of altruistic be-havior under some assumptions regarding genome related-ness. In-depth experimental studies explore the relation be-tween genotypic diversity and degree of altruism as well as the exact nature of the evolutionary adaptation process.
In a previous issue of this journal, Adam Goodwin (2010) argued that applications of ‘orthodox’ evolutionary theory in international relations are reductionist, necessarily privilege an individualist ontology, and doom social theorising to the false assumption that humans are by nature selfish and competitive. As an alternative, Goodwin presents Kropotkin’s Mutual Aid framework both for overcoming the reductionism of ‘orthodox’ evolutionary theory and for establishing a holist ontology cantered around the autonomy of social forms. I argue that Goodwin’s representation of ‘orthodox’ evolutionary theory is in fact far from orthodoxy and instead rests on misunderstandings both of how natural selection operates and what it operates to produce – adaptations. I show that modern evolutionary theory rests on neither individualist nor holist ontologies, and instead demonstrates that humans are by nature neither hawkish nor dovish. I provide examples on the evolution of cooperation and war to demonstrate that modern evolutionary theory can explain a range of pro- and anti-social behaviours and that fears of biological reductionism in international relations are misplaced.
Why some social systems form groups composed of kin, while others do not, has gone largely untreated in the literature. Using an individual‐based simulation model, we explore the demographic consequences of making kinship a criterion in group formation. We find that systems where social groups consist of one‐generation breeding associations may face a serious trade‐off between degree of altruism and group size that is largely mediated by their kin composition. On the one hand, restricting groups to close kin allows the evolution of highly altruistic behaviors but may limit group size to suboptimal levels, the more severely so the smaller the intrinsic fecundity of the species and the stricter the kin admission rule. Group size requirements, on the other hand, can be met by admitting nonkin into groups, but not without limiting the degree of altruism that can evolve. As a solution to this conundrum, we show that if helping roles within groups are assigned through a lottery rather than being genetically determined, maximum degrees of altruism can evolve in groups of nonrelatives of any size. Such a “lottery” mechanism may explain reproductive and helping patterns in organisms as varied as the cellular slime molds, pleometrotic ants, and Galapagos hawks.
This article studies the transition in evolution from single cells to multicellular organisms as a case study in the origin of individuality. The issues considered are applicable to all major transitions in the units of selection that involve the emergence of cooperation and the regulation of conflict. Explicit genetic models of mutation and selection both within and between organisms are studied. Cooperation among cells increases when the fitness covariance at the level of the organism overcomes within-organism change toward defection. Selection and mutation during development generate significant levels of within-organism variation and lead to variation in organism fitness at equilibrium. This variation selects for gem-line modifiers and other mediators of within-organism conflict, increasing the heritability of fitness at the organism level. The evolution of these modifiers is the first new function at the emerging organism level and a necessary component of the evolution of individuality.
In organisms possessing a dispersal phase the processes of mating,
competition, feeding, and predation are often carried out within
``trait-groups,'' defined as populations enclosed in areas smaller than
the boundaries of the deme. A simple model shows that this can lead to
the selection of ``altruistic'' traits that favor the fitness of the
group over that of the individual. The extent of group selection that
occurs depends mainly on the variation in the composition of genotypes
between trait-groups. The traditional concepts of group and individual
selection are seen as two extremes of a continuum, with systems in
nature operating over the interval in between.
Inclusive-fitness models have been critized because they give incorrect results for cases in which fitness components interact nonadditively. However, this failure is not due to anything intrinsic to the inclusive-fitness viewpoint. It stems from an essentially quantitative genetic feature of the model, an attempt to separate fitness terms from genetic terms. A general rule is provided for determining when such a separation is justified. This rule is used to show how Price's covariance equation is related to standard quantitative genetic results and to derive quantitative genetic equations for inclusive fitness and group selection. It also shows that the group-selection model is no more general than the inclusive-fitness viewpoint. These models serve a role that is different from, but not inferior to, population-genetics models. Although they are less exact under some conditions, like quantitative genetic models in general, they provide us with measurable parameters.
Group selection is defined as that process of genetic change which is caused by the differential extinction or proliferation of groups of organisms. A very large proportion of the literature pertaining to group selection consists of theoretical papers; the genetic problems of group selection have been addressed from many different mathematical viewpoints. The general conclusion has been that, although group selection is possible, it cannot override the effects of individual selection within populations except for a highly restricted set of parameter values. Since it is unlikely that conditions in natural populations would fall within the bounds imposed by the models, group selection, by and large, has been considered an insignificant force for evolutionary change. These theoretical conclusions and the assumptions from which they have been derived are reexamined in the light of recent empirical studies of group selection with laboratory populations of the flour beetle, Tribolium (Wade, 1976, 1977). It is s...
The fitness of any evolutionary unit can be understood in terms of its two basic com- ponents: fecundity (reproduction) and viability (survival). Trade-offs between these fitness com- ponents drive the evolution of life-history traits in extant multicellular organisms. We argue that these trade-offs gain special significance during the transition from unicellular to multicellular life. In particular, the evolution of germ-soma specialization and the emergence of individuality at the cell group (or organism) level are also consequences of trade-offs between the two basic fitness components, or so we argue using a multilevel selection approach. During the origin of multi- cellularity, we study how the group trade-offs between viability and fecundity are initially deter- mined by the cell level trade-offs, but as the transition proceeds, the fitness trade-offs at the group level depart from those at the cell level. We predict that these trade-offs begin with concave curvature in single-celled organisms but become increasingly convex as group size increases in multicellular organisms. We argue that the increasingly convex curvature of the trade-off function is driven by the cost of reproduction which increases as group size increases. We consider aspects of the biology of the volvocine green algae - which contain both unicellular and multicellular members - to illustrate the principles and conclusions discussed.
A model is presented to account for the natural selection of what is termed reciprocally altruistic behavior. The model shows how selection can operate against the cheater (non-reciprocator) in the system. Three instances of altruistic behavior are discussed, the evolution of which the model can explain: (1) behavior involved in cleaning symbioses; (2) warning cries in birds; and (3) human reciprocal altruism. Regarding human reciprocal altruism, it is shown that the details of the psychological system that regulates this altruism can be explained by the model. Specifically, friendship, dislike, moralistic aggression, gratitude, sympathy, trust, suspicion, trustworthiness, aspects of guilt, and some forms of dishonesty and hypocrisy can be explained as important adaptations to regulate the altruistic system. Each individual human is seen as possessing altruistic and cheating tendencies, the expression of which is sensitive to developmental variables that were selected to set the tendencies at a balance ap...
Both laboratory and field data suggest that people punish noncooperators
even in one-shot interactions. Although such ‘‘altruistic
punishment’’ may explain the high levels of cooperation in human
societies, it creates an evolutionary puzzle: existing models suggest
that altruistic cooperation among nonrelatives is evolutionarily
stable only in small groups. Thus, applying such models to the
evolution of altruistic punishment leads to the prediction that
people will not incur costs to punish others to provide benefits to
large groups of nonrelatives. However, here we show that an
important asymmetry between altruistic cooperation and altruistic
punishment allows altruistic punishment to evolve in populations
engaged in one-time, anonymous interactions. This process allows
both altruistic punishment and altruistic cooperation to be maintained
even when groups are large and other parameter values
approximate conditions that characterize cultural evolution in
the small-scale societies in which humans lived for most of our
prehistory. PNAS vol. 100, pgs. 3531-3535
The definition of second order interaction in a (2 × 2 × 2) table given by Bartlett is accepted, but it is shown by an example that the vanishing of this second order interaction does not necessarily justify the mechanical procedure of forming the three component 2 × 2 tables and testing each of these for significance by standard methods.*
A group-selection model is presented in which each group is initiated by a single fertilized female and persists for several generations before dispersal. Maynard Smith (1964) concluded that altruism could not plausibly evolve under these circumstances. I show that his conclusion is an artifact of a simplifying assumption that amounts to a worst-case scenario for group selection. When the standard donor-recipient equations for altruistic behavior are used in Maynard Smith's model, Mendelian populations derived from sibling groups are often more favorable for the evolution of altruism than are the sibling groups themselves. In general, long-term and large-scale aspects of population structure may at times be important in the evolution of altruistic and other group-advantageous behaviors.
Conflicts between animals of the same species usually are of ``limited
war'' type, not causing serious injury. This is often explained as due
to group or species selection for behaviour benefiting the species
rather than individuals. Game theory and computer simulation analyses
show, however, that a ``limited war'' strategy benefits individual
animals as well as the species.
Group selection is defined as a process by which traits advantageous to the group of favored because of the positive association of individuals exhibiting the traits. Group selection acts to protect this positive association against cheats. Kin selection is considered an example of group selection in which the 'groups' are associations of relatives and in which special mechanisms, such as individual recognition, maintain the integrity of the associations. The 'groups' of group selection are quite different from the trait groups of structured-deme models, so that structured-deme models can be used to demonstrate individual or group selection. By analyzing the models in terms of group neighbors, it is shown that whenever trait groups are formed at random only individual selection can act. The same results have emerged when there are no groups, only a continuous random array of individuals, and the analysis is in terms of neighborhoods. Individuals exhibiting traits that can evolve under these conditions of neighborhood selection often impart some benefit to their neighbors. Such traits are said to be benevolent. Altruism involves a loss of individual fitness and can evolve only by group selection. The evolution of altruism can be demonstrated in structured-deme models, provided that the altruists exhibit positive association and can occur whether the population forms isolated groups or a continuous array.-from Author
Axelrod and Hamilton (1981) used the repeated prisoner's dilemma game as a basis for their widely cited analysis of the evolution of reciprocal altruism. Recently, it has been argued that the repeated prisoner's dilemma is not a good model for this task. Some critics have argued that the single period prisoner's dilemma represents mutualistic rather than altruistic social interactions. Others have argued that reciprocal altruism requires that the opportunities for altruism occur sequentially, first one individual and then after some delay the other. Here I begin by arguing that the single period prisoner's dilemma game is consistent with the definition of altruism that is widely accepted in evolutionary biology. Then I present two modified versions of the repeated prisoner's dilemma, one in which behavior is sequential, and a second in which behavior occurs in continuous time. Each of these models shares the essential qualitative properties with the version used by Axelrod and Hamilton.
1. Most organisms interact with a set of neighbors smaller than the deme (its trait group). Demes therefore are not only a population of individuals but also a population of groups (structured demes). 2. Trait groups vary in their composition. The minimum variance to be expected is that arising from a binomial distribution. Most populations have a higher variance than this due to (a) differential interactions with the environment and (b) the effects of reproduction inside the trait groups. 3. As a consequence of this variation, an individual on the average experiences its own "type" in a greater frequency than actually exists in the deme. Its behaviors are therefore directed differentially toward fellow types, and this is the fundamental requirement for the evolution of altruism. 4. Models are presented for warning cries and other donor-recipient relations, resource notification, the evolution of prudence in exploitation and interference competition, and the effect of differential trait-group extinction. ...
A group-selection model is presented in which each group is initiated by a single fertilized female and persists for several generations before dispersal. Maynard Smith (1964) concluded that altruism could not plausibly evolve under these circumstances. His conclusion is an artifact of a simplifying assumption that amounts to a worst-case scenario for group selection. When the standard donor-recipient equations for altruistic behavior are used in Maynard Smith's model, Mendelian populations derived from sibling groups are often more favorable for the evolution of altruism than are the sibling groups themselves. In general, long-term and large-scale aspects of population structure may at times be important in the evolution of altruistic and other group-advantageous behaviors -from Author
The book is divided into eight chapters. The first provides a historical perspective on cooperative behaviour. The second chapter examines theoretical perspectives on the evolution of cooperation: inclusive fitness; within- and between-group selection; reciprocity and the prisoner's dilemma; byproduct mutualism; and the cooperator's dilemma game. The next five chapters look at cooperative behaviour in a number of animal groups: fish; birds; nonprimates; nonhuman primates; and insects. The final chapter sets out the direction in which the author hopes the field will move in the future.
Human cultural groups appear well designed, but is this apparent design due to altruism or due to self-serving behaviours? Sober and Wilson argue that human cultures are founded on group-selected altruism. This argument assumes that individually selected self-serving traits are not being misidentified as altruistic. A simple definition of individual selection suggests that Sober and Wilson fail to separate one such trait, called benevolence, from altruism. Benevolent individuals act selfishly but provide an incidental benefit to their neighbours. The female-biased Hamiltonian sex ratios are used to illustrate benevolence, and a financial analogy is used to emphasize why such traits are individually advantageous. Benevolence can only evolve in a spatially structured population, illustrating the importance of separating individual selection in structured and unstructured populations. Unlike benevolence, altruism can only evolve by group selection and, as a result, is vulnerable to selfish cheats that exploit the self-sacrifice of altruists.
We address the following issues raised by the commentators of our target article and book: (1) the problem of multiple perspectives; (2) how to define group selection; (3) distinguishing between the concepts of altruism and organism; (4) genetic versus cultural group selection; (5) the dark side of group selection; (6) the relationship between psychological and evolutionary altruism; (7) the question of whether the psychological questions can be answered; (8) psychological experiments. We thank the contributors for their commentaries, which provide a diverse agenda for future study of evolution and morality. Our response will follow the organization of our book, distinguishing between evolutionary issues that concern fitness effects and psychological issues that concern motives.
There are two ways to model the genetic evolution of social behaviour. Population genetic models using personal fitness1 –9 may be exact and of wide applicability, but they are often complex and assume very different forms for different kinds of social behaviour. The alternative, inclusive fitness models10 –12, achieves simplicity and clarity by attributing all fitness effects of a behaviour to an expanded fitness of the actor. For example, Hamilton's rule states that an altruistic behaviour will be favoured when −c + rb>0, where c is the fitness cost to the altruist, b is the benefit to its partner, and r is their relatedness. But inclusive fitness results are often inexact for interactions between kin1–5, and they do not address phenomena such as reciprocity13–15 and synergistic effects7,8,16 that may either be confounded with kinship or operate in its absence. Here I develop a model the results of which may be expressed in terms of either personal or inclusive fitness, and which combines the advantages of both; it is general, exact, simple and empirically useful. Hamilton's rule is shown to hold for reciprocity as well as kin selection. It fails because of synergistic effects, but this failure can be corrected through the use of coefficients of synergism, which are analogous to the coefficient of relatedness.
The problem of collective action to produce a group collective good is analyzed as the game of Individual vs. Collective and then as an n-person game to show that, under the constraints of Mancur Olson's analysis, it is an n-prisoners' dilemma in the cases of latent and intermediate groups. The usual analysis according to which noncooperation is considered the rational strategy for classical 2-prisoners' dilemma is logically similar to Olson's analysis, which suggests that rational members of a latent group should not contribute toward the purchase of the group collective good. However, in the game analysis it is clear that the latent and intermediate groups are not logically different, but rather are distinguishable only statistically. Some prisoners' dilemma experimental results are used to suggest how the difference might arise and how the vast prisoners' dilemma literature can be related to the problem of collective action.
The game of collective action is then analyzed not from the view of strategies but of outcomes. There is presented a theorem which states that the outcome in which all player-members of a group pay and all benefit is a Condorcet choice from the set of realizable outcomes for the game. Hence the cooperative outcome in such a game would prevail in election against all other outcomes.
The group selection controversy has been dominated by 2 major themes: 1) involving the selection of groups in a metapopulation as a process analogous to the selection of individuals within single groups; and 2) involving altruistic behaviors that benefit others at the expense of the individual actor. This essay points out some inconsistencies between the 2 themes. It is reasonable to expect strong group selection to operate in random associations, without any genetic relatedness among group members. -from Author
Evolutionary biologists have grappled with the question of the emergenceand maintenance of cooperation since Darwin first listed animal cooperation asapotential problem for his theory of natural selection. Here I review four pathsthat have been delineated in the study of intra-specific cooperation amonganimals. These paths – kinship, reciprocity, byproduct mutualism andgroupselection – serve as a starting point for behavioral ecologistsinterestedstudying the initiation and maintenance of cooperation. After reviewing theempirical and theoretical underpinnings of these paths to cooperation, I touchupon some recent work that has attempted to examine (or reexamine) the role ofphylogeny, punishment and morality in the light of cooperative behavior.
Recent years have seen a renewed debate over the importance of groupselection, especially as it relates to the evolution of altruism. Onefeature of this debate has been disagreement over which kinds ofprocesses should be described in terms of selection at multiple levels,within and between groups. Adapting some earlier discussions, we presenta mathematical framework that can be used to explore the exactrelationships between evolutionary models that do, and those that donot, explicitly recognize biological groups as fitness-bearing entities.We show a fundamental set of mathematical equivalences between these twokinds of models, one of which applies a form of multi-level selectiontheory and the other being a form of ``individualism.'' However, we alsoargue that each type of model can have heuristic advantages over theother. Indeed, it can be positively useful to engage in a kind ofback-and-forth switching between two different perspectives on theevolutionary role of groups. So the position we defend is a``gestalt-switching pluralism.''
In what sense can the self-sacrificing sterile ant be considered to "struggle for existence" or to endeavor to maximize the numbers of its descendants? Since the founding of the theory of evolution by natural selection, most biologists have evaded this question by focusing attention exclusively on the colony as the reproducing unit. There is a powerful precedent for this. Darwin himself took this course. He saw only a "minor" difficulty in the evolution of sterility, and he passed over it in a few lines as he proceeded to discuss the "great" difficulty of how the special aptitudes of the workers could be passed on in latent form by their fertile sisters (26). A difficulty over sterility exists, nevertheless, and it is the more surprising that Darwin should have passed over it in that he discussed-but left unsolved-a parallel one raised by the social virtues (courage and self-sacrifice) in man (25). He saw that such qualities would be promoted in intergroup selection but counter-selected within each group. Perhaps the possible avenues of indiscipline in social insects had been so little reported in Darwin's time that the problems they raised were easily overlooked. Darwin's inadequate understanding of heredity may, likewise, have helped to keep the problem out of focus. With better knowledge of heredity and with more facts regarding the social insects to draw upon, Weismann (154) recognized the possible conflict between intergroup and intragroup selection in the evolution of worker attributes. He made the perceptive comment that, "Obviously the workers must be more rapidly improved when all in a hive are progeny of one queen-i.e. they are all alike or almost alike." But this comment was made in the course of discussion of another topic, and he did not pursue the matter. Soon Mendelian genetics resolved Darwin's difficulty of latency, apart from details of mechanism. But the disappearance of this problem does not seem to have given greater prominence to the other, and the question of how worker sterility comes to be selected continued to receive only occasional comment for a long time. Sturtevant (142) in 1938 again outlined it with admirable clarity and with special reference to multiqueened (polygynic) organization, which was by then well known. Rau (118) in 1940 also briefly touched on this crux when he noted how small might be the step separating workerlike behavior in auxiliary Polistes queens 193
Covariance models of selection predict gene frequency change in terms of the relationship between the fitness of an individual and its phenotype, and therefore provide a convenient method for studying evolution in natural systems. When these models are partitioned into effects acting within and between hierarchical levels of selection, they can be directly applied to questions of kin selection. In many cases, the partitioning of covariance approach to the study of kin selection is a more useful alternative to the traditional hamiltonian or inclusive fitness approach.