Evolutionary Psychology: The Burdens of Proof

I discuss two types of evidential problems with the most widely touted experiments in evolutionary psychology, those performed by Leda Cosmides and interpreted by Cosmides and John Tooby. First, and despite Cosmides and Tooby's claims to the contrary, these experiments don't fulfil the standards of evidence of evolutionary biology. Second Cosmides and Tooby claim to have performed a crucial experiment, and to have eliminated rival approaches. Though they claim that their results are consistent with their theory but contradictory to the leading non-evolutionary alternative, Pragmatic Reasoning Schemas theory, I argue that this claim is unsupported. In addition, some of Cosmides and Tooby's interpretations arise from misguided and simplistic understandings of evolutionary biology. While I endorse the incorporation of evolutionary approaches into psychology, I reject the claims of Cosmides and Tooby that a modular approach is the only one supported by evolutionary biology. Lewontin's critical examinations of the applications of adaptationist thinking provide a background of evidentiary standards against which to view the currently fashionable claims of evolutionary psychology.     

Some Recent Developments in Evolutionary Approaches to the Study of Human Cognition and Behavior

In this paper I review some theoretical exchanges and empiricalresults from recent work on human behavior and cognition in thehope of indicating some productive avenues for critical engagement.I focus particular attention on methodological debates between Evolutionary Psychologists and behavioral ecologists. I argue for a broader and more encompassing approach to the evolutionarily based study of human behavior and cognition than either of these two rivals present.     

Altruism in networks: the effect of connections

Why are individuals altruistic to their friends? Theory suggests that individual, relationship and network factors will all influence the levels of altruism; but to date, the effects of social network structure have received relatively little attention. The present study uses a novel correlational design to test the prediction that an individual will be more altruistic to friends who are well-connected to the individual''s other friends. The result shows that, as predicted, even when controlling for a range of individual and relationship factors, the network factor (number of connections) makes a significant contribution to altruism, thus showing that individuals are more likely to be altruistic to better-connected members of their social networks. The implications of incorporating network structure into studies of altruism are discussed.     

Altruism in viscous populations — an inclusive fitness model

Summary A viscous population (Hamilton, 1964) is one in which the movement of organisms from their place of birth is relatively slow. This viscosity has two important effects: one is that local interactions tend to be among relatives, and the other is that competition for resources tends to be among relatives. The first effect tends to promote and the second to oppose the evolution of altruistic behaviour. In a simulation model of Wilsonet al. (1992) these two factors appear to exactly balance one another, thus opposing the evolution of local altruistic behaviour. Here I show, with an inclusive fitness model, that the same result holds in a patchstructured population.     

How a Kantian Can Accept Evolutionary Metaethics

Contrary to widely held assumptions, an evolutionary metaethics need not be non-cognitivist. I define evolutionary metaethics as the claim that certain phenotypic traits expressing certain genes are both necessary and sufficient for explanation of all other phenotypic traits we consider morally significant. A review of the influential cognitivist Immanuel Kants metaethics shows that much of his ethical theory is independent of the anti-naturalist metaphysics of transcendental idealism which itself is incompatible with evolutionary metaethics. By matching those independent aspects to an evolutionary metaethics a cognitivist Kantian evolutionary metaethical theory is a possibility for researchers to consider.     

Altruism and Reward: Motivational Compatibility in Deceased Organ Donation

Acts of helping others are often based on mixed motivations. Based on this claim, it has been argued that the use of a financial reward to incentivize organ donation is compatible with promoting altruism in organ donation. In its report Human Bodies: Donation for Medicine and Research, the Nuffield Council on Bioethics uses this argument to justify its suggestion to pilot a funeral payment scheme to incentivize people to register for deceased organ donation in the UK. In this article, I cast a sceptical eye on the above Nuffield report's argument that its proposed funeral payment scheme would prompt deceased organ donations that remain altruistic (as defined by and valued the report). Specifically, I illustrate how this scheme may prompt various forms of mixed motivations which would not satisfy the report's definition of altruism. Insofar as the scheme produces an expectation of the reward, it stands diametrical to promoting an ‘altruistic perspective’. My minimal goal in this article is to argue that altruism is not motivationally compatible with reward as an incentive for donation. My broader goal is to argue that if a financial reward is used to incentivize organ donation, then we should recognize that the donation system is no longer aiming to promote altruism. Rewarded donation would not be altruistic but it may be ethical given a persistent organ shortage situation.     

Evolutionary Change and Epistemology

This paper is concerned with the debate in evolutionary epistemology about the nature of the evolutionary process at work in the development of science: whether it is Darwinian or Lamarckian. It is claimed that if we are to make progress through the many arguments that have grown up around this issue, we must return to an examination of the concepts of change and evolution, and examine the basic kinds of mechanism capable of bringing evolution about. This examination results in two kinds of processes being identified, dubbed direct and indirect, and these are claimed to exhaust all possibilities. These ideas are then applied to a selection of the debates within evolutionary epistemology. It is shown that while arguments about the pattern and rate of evolutionary change are necessarily inconclusive, those concerning the origin of novel variations and the mode of inheritance can be resolved by means of the distinctions made here. It is claimed that the process of selection in the evolution of science can also be clarified. The conclusion is that the main process producing the evolution of science is a direct or Lamarckian one although, if realism is correct, an indirect or Darwinian process plays a vital role.     

First- and second-order sociality determine survival and reproduction in cooperative cichlids

Cooperative breeders serve as a model to study the evolution of cooperation, where costs and benefits of helping are typically scrutinized at the level of group membership. However, cooperation is often observed in multi-level social organizations involving interactions among individuals at various levels. Here, we argue that a full understanding of the adaptive value of cooperation and the evolution of complex social organization requires identifying the effect of different levels of social organization on direct and indirect fitness components. Our long-term field data show that in the cooperatively breeding, colonial cichlid fish Neolamprologus pulcher, both large group size and high colony density significantly raised group persistence. Neither group size nor density affected survival at the individual level, but they had interactive effects on reproductive output; large group size raised productivity when local population density was low, whereas in contrast, small groups were more productive at high densities. Fitness estimates of individually marked fish revealed indirect fitness benefits associated with staying in large groups. Inclusive fitness, however, was not significantly affected by group size, because the direct fitness component was not increased in larger groups. Together, our findings highlight that the reproductive output of groups may be affected in opposite directions by different levels of sociality, and that complex forms of sociality and costly cooperation may evolve in the absence of large indirect fitness benefits and the influence of kin selection.     

进化生态学的产生与发展

进化论、遗传学与生态学是在不同时期发展起来的独立学科,然而,随着科学的发展,们越来越认识到它们之间存在着密切的关系。Petrusewicz(1959)(见Shvarts,1977)曾写过《达尔文进化论是一种生态理论》一书,强调进化在本质上是一生态过程。Hutchinson(1965)写了一部题名为《生态学舞台和进化节目》一书,认为生态的布景可以作为进化过程的舞台。但是,最早提出进化生态学这一概念的则是Orians(1962)。进化生态学从产生到现在虽然只有20多年的历史,但已成为生态学研究的重要领域。下面从几个方面谈谈进化生态学的产生与发展。     

Evolutionary rescue and the limits of adaptation

Populations subject to severe stress may be rescued by natural selection, but its operation is restricted by ecological and genetic constraints. The cost of natural selection expresses the limited capacity of a population to sustain the load of mortality or sterility required for effective selection. Genostasis expresses the lack of variation that prevents many populations from adapting to stress. While the role of relative fitness in adaptation is well understood, evolutionary rescue emphasizes the need to recognize explicitly the importance of absolute fitness. Permanent adaptation requires a range of genetic variation in absolute fitness that is broad enough to provide a few extreme types capable of sustained growth under a stress that would cause extinction if they were not present. This principle implies that population size is an important determinant of rescue. The overall number of individuals exposed to selection will be greater when the population declines gradually under a constant stress, or is progressively challenged by gradually increasing stress. In gradually deteriorating environments, survival at lethal stress may be procured by prior adaptation to sublethal stress through genetic correlation. Neither the standing genetic variation of small populations nor the mutation supply of large populations, however, may be sufficient to provide evolutionary rescue for most populations.     

Tag-based indirect reciprocity by incomplete social information

Evolution of altruistic behaviour in interacting individuals is accounted for by, for example, kin selection, direct reciprocity, spatially limited interaction and indirect reciprocity. Real social agents, particularly humans, often take actions based on similarity between themselves and others. Although tag-based indirect reciprocity in which altruism occurs exclusively among similar flocks is a natural expectation, its mechanism has not really been established. We propose a model of tag-based indirect reciprocity by assuming that each player may note strategies of others. We show that tag-based altruism can evolve to eradicate other strategies, including unconditional defectors for various initial strategy configurations and parameter sets. A prerequisite for altruism is that the strategy is sometimes, but not always, visible to others. Without visibility of strategies, policing does not take place and defection is optimal. With perfect visibility, what a player does is always witnessed by others and cooperation is optimal. In the intermediate regime, discriminators based on tag proximity, rather than mixture of generous players and defectors, are most likely to evolve. In this situation, altruism is realized based on homophily in which players are exclusively good to similar others.     

基因组功能预测的进化印记方法

改善基因组功能预测方案是目前功能基因组学的迫切问题,生物进化历程会在分子序列上留下相应进化印记－直系同源簇的特异模体,在这一生物学事实的基础上,提出了一个新的基因缚功能预测方法,首先利用进化分析方法构建直系同源簇,再找到各直系同源簇的功能模体,这样可以形成特异的功能模体库,未知基因的功能预测可望通过搜索该功能模体库而得以高效,准确地完成,对５个家族的检验初步证实该方案是可行的。     

Evolutionary causes and consequences of consistent individual variation in cooperative behaviour

Behaviour is typically regarded as among the most flexible of animal phenotypic traits. In particular, expression of cooperative behaviour is often assumed to be conditional upon the behaviours of others. This flexibility is a key component of many hypothesized mechanisms favouring the evolution of cooperative behaviour. However, evidence shows that cooperative behaviours are often less flexible than expected and that, in many species, individuals show consistent differences in the amount and type of cooperative and non-cooperative behaviours displayed. This phenomenon is known as ‘animal personality’ or a ‘behavioural syndrome’. Animal personality is evolutionarily relevant, as it typically shows heritable variation and can entail fitness consequences, and hence, is subject to evolutionary change. Here, we review the empirical evidence for individual variation in cooperative behaviour across taxa, we examine the evolutionary processes that have been invoked to explain the existence of individual variation in cooperative behaviour and we discuss the consequences of consistent individual differences on the evolutionary stability of cooperation. We highlight that consistent individual variation in cooperativeness can both stabilize or disrupt cooperation in populations. We conclude that recognizing the existence of consistent individual differences in cooperativeness is essential for an understanding of the evolution and prevalence of cooperation.     

演化计算的应用研究

介绍了演化计算的基本思想、特点及主要分支。在统一的枢架下给出了演化算法的设计方法和基本结构,并给出了演化计算在旅行商问题中的应用。最后讨论了演化计算的发展前景。     

长江流域的生物多样性及其与经济协调发展的对策

长江流域的生物多样性及其与经济协调发展的对策陈家宽李博（武汉大学生命科学学院,武汉４３００７２）吴千红（复旦大学生命科学学院,上海２００４３３）众所周知,生物多样性（ｂｉｏｄｉｖｅｒｓｉｔｙ）是当代国际社会日益关注的重大问题之一。生物多样性是人类赖以...