Part I. Experimental Studies: 2. Experiment in psychology 3. Experiments on perceiving III Experiments on imaging 4-8. Experiments on remembering: (a) The method of description (b) The method of repeated reproduction (c) The method of picture writing (d) The method of serial reproduction (e) The method of serial reproduction picture material 9. Perceiving, recognizing, remembering 10. A theory of remembering 11. Images and their functions 12. Meaning Part II. Remembering as a Study in Social Psychology: 13. Social psychology 14. Social psychology and the matter of recall 15. Social psychology and the manner of recall 16. Conventionalism 17. The notion of a collective unconscious 18. The basis of social recall 19. A summary and some conclusions.

Remembering. A Study in Experimental and Social Psychology, Cambridge (University Press) 1964.

Cooperation is needed for evolution to construct new levels of organization. Genomes, cells, multicellular organisms, social insects, and human society are all based on cooperation. Cooperation means that selfish replicators forgo some of their reproductive potential to help one another. But natural selection implies competition and therefore opposes cooperation unless a specific mechanism is at work. Here I discuss five mechanisms for the evolution of cooperation: kin selection, direct reciprocity, indirect reciprocity, network reciprocity, and group selection. For each mechanism, a simple rule is derived that specifies whether natural selection can lead to cooperation.

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Five Rules for the Evolution of Cooperation

BIOE 402. Medical Technology Assessment. 2 or 3 hours. Bioentrepreneur course. Assessment of medical technology in the context of commercialization. Objectives, competition, market share, funding, pricing, manufacturing, growth, and intellectual property; many issues unique to biomedical products. Course Information: 2 undergraduate hours. 3 graduate hours. Prerequisite(s): Junior standing or above and consent of the instructor.

“Bioinformatics” 특집을 내면서

Human cooperation is an evolutionary puzzle. Unlike other creatures, people frequently cooperate with genetically unrelated strangers, often in large groups, with people they will never meet again, and when reputation gains are small or absent. These patterns of cooperation cannot be explained by the nepotistic motives associated with the evolutionary theory of kin selection and the selfish motives associated with signalling theory or the theory of reciprocal altruism. Here we show experimentally that the altruistic punishment of defectors is a key motive for the explanation of cooperation. Altruistic punishment means that individuals punish, although the punishment is costly for them and yields no material gain. We show that cooperation flourishes if altruistic punishment is possible, and breaks down if it is ruled out. The evidence indicates that negative emotions towards defectors are the proximate mechanism behind altruistic punishment. These results suggest that future study of the evolution of human cooperation should include a strong focus on explaining altruistic punishment.

/pdf/altruistic-punishment-in-humans-4yytzjzmsy.pdf

Altruistic punishment in humans.

Human cooperation is an evolutionary puzzle. Unlike other creatures, people frequently cooperate with genetically unrelated strangers, often in large groups, with people they will never meet again, and when reputation gains are small or absent. These patterns of cooperation cannot be explained by the nepotistic motives associated with the evolutionary theory of kin selection and the sel®sh motives associated with signalling theory or the theory of reciprocal altruism. Here we show experimentally that the altruistic punishment of defectors is a key motive for the explanation of cooperation. Altruistic punishment means that individuals punish, although the punishment is costly for them and yields no material gain. We show that cooperation ¯ourishes if altruistic punishment is possible, and breaks down if it is ruled out. The evidence indicates that negative emotions towards defectors are the proximate mechanism behind altruistic punishment. These results suggest that future study of the evolution of human cooperation should include a strong focus on explaining altruistic punishment.

Altruistic Punishment in Humans

Wolbachia are intracellular bacteria found in many species of arthropods and nematodes They manipulate the reproduction of their arthropod hosts in various ways, may play a role in host speciation and have potential applications in biological pest control Estimates suggest that at least 20% of all insect species are infected with Wolbachia These estimates result from several Wolbachia screenings in which numerous species were tested for infection; however, tests were mostly performed on only one to two individuals per species The actual percent of species infected will depend on the distribution of infection frequencies among species We present a meta-analysis that estimates percentage of infected species based on data on the distribution of infection levels among species We used a beta-binomial model that describes the distribution of infection frequencies of Wolbachia, shedding light on the overall infection rate as well as on the infection frequency within species Our main findings are that (1) the proportion of Wolbachia-infected species is estimated to be 66%, and that (2) within species the infection frequency follows a ‘most-or-few’ infection pattern in a sense that the Wolbachia infection frequency within one species is typically either very high (>90%) or very low (<10%)

How many species are infected with Wolbachia?--A statistical analysis of current data.

Wolbachia are intracellular bacteria that manipulate the reproduction of their arthropod hosts in remarkable ways. They are predominantly transmitted vertically from mother to offspring but also occasionally horizontally between species. In doing so, they infect a huge range of arthropod species worldwide. Recently, a statistical analysis estimated the infection frequency of Wolbachia among arthropod hosts to be 66%. At the same time, the authors of this analysis highlighted some weaknesses of the underlying data and concluded that in order to improve the estimate, a larger number of individuals per species should be assayed and species be chosen more randomly. Here we apply the statistical approach to a more appropriate data set from a recent survey that tested both a broad range of species and a sufficient number of individuals per species. Indeed, we find a substantially different infection frequency: We now estimate the proportion of Wolbachia-infected species to be around 40% which is lower than the previous estimate but still points to a surprisingly high number of arthropods harboring the bacteria. Notwithstanding this difference, we confirm the previous result that, within a given species, typically most or only a few individuals are infected. Moreover, we extend our analysis to include several reproductive parasites other than Wolbachia that were also screened for in the aforementioned empirical survey. For these symbionts we find a large variation in estimated infection frequencies and corroborate the finding that Wolbachia are the most abundant endosymbionts among arthropod species.

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Still a Host of Hosts for Wolbachia : Analysis of Recent Data Suggests That 40% of Terrestrial Arthropod Species Are Infected

The formation of collaborating pairs by indi- viduals belonging to two different classes occurs in the contexts of reproduction and intra-specific cooperation as well as of inter-specific mutualism. There is potential for partner choice and for competition for access to pre- ferred partners in all three contexts. These selective forces have long been recognised as important in sexual selection, but their impact is not yet appreciated in co- operative and mutualistic systems. The formation of partnerships between members of different classes has much in common with the conclusion of trade agree- ments in human markets with two classes of traders, like producers and consumers, or employers and employees. Similar game-theoretical models can be used to predict the behaviour of rational traders in human markets and the evolutionarily stable strategies used in biological markets. We present a formal model in which the influ- ence of the market mechanism on selection is made ex- plicit. We restrict ourselves to biological markets in which: (1) Individuals do not compete over access to partners in an agonistic manner, but rather by outcom- peting each other in those aspects that are preferred by the choosing party. (2) The commodity the partner has to offer cannot be obtained by the use of force, but re- quires the consent of the partner. These two restrictions ensure a dominant role for partner choice in the forma- tion of partnerships. In a biological market model the decision to cooperate is based on the comparison be- tween the offers of several potential partners, rather than on the behaviour of a single potential partner, as is implicitly assumed in currently accepted models of co- operation. In our example the members of one class A offer a commodity of fixed value in exchange for a com- modity of variable value supplied by the other class, B. We show that when the B-class outnumbers the A-class sufficiently and the cost for the A-class to sample the offers of the B-class are low, the choosiness of the A-

Biological markets: supply and demand determine the effect of partner choice in cooperation, mutualism and mating

How can cooperation through indirect reciprocity evolve and what would it be like? This problem has previously been studied by simulating evolution in a small group of interacting individuals, assuming no gene flow between groups. In these simulations, certain 'image scoring' strategies were found to be the most successful. However, analytical arguments show that it would not be in an individual's interest to use these strategies. Starting with this puzzle, we investigate indirect reciprocity in simulations based on an island model. This has an advantage in that the role of genetic drift can be examined. Our results show that the image scoring strategies depend on very strong drift or a very small cost of giving help. As soon as these factors are absent, selection eliminates image scoring. We also consider other possibilities for the evolution of indirect reciprocity. In particular, we find that the strategy of aiming for 'good standing' has superior properties. It can be an evolutionarily stable strategy and, even if not, it usually beats image scoring. Furthermore, by introducing quality variation among individuals into the model, we show that the standing strategy can be quality revealing, adding a new dimension to indirect reciprocity. Finally, we discuss general problems with currently popular modelling styles.

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Evolution of cooperation through indirect reciprocity

The latest interdisciplinary research on the evolutionary models of cooperation. Current thinking in evolutionary biology holds that competition among individuals is the key to understanding natural selection. When competition exists, it is obvious that conflict arises; the emergence of cooperation, however, is less straightforward and calls for in-depth analysis. Much research is now focused on defining and expanding the evolutionary models of cooperation. Understanding the mechanisms of cooperation has relevance for fields other than biology. Anthropology, economics, mathematics, political science, primatology, and psychology are adopting the evolutionary approach and developing analogies based on it. Similarly, biologists use elements of economic game theory and analyze cooperation in "evolutionary games." Despite this, exchanges between researchers in these different disciplines have been limited. Seeking to fill this gap, the 90th Dahlem Workshop was convened. This book, which grew out of that meeting, addresses such topics as emotions in human cooperation, reciprocity, biological markets, cooperation and conflict in multicellularity, genomic and intercellular cooperation, the origins of human cooperation, and the cultural evolution of cooperation; the emphasis is on open questions and future research areas. The book makes a significant contribution to a growing process of interdisciplinary cross-fertilization on this issue.

Peter Hammerstein

Papers

How many species are infected with Wolbachia?--A statistical analysis of current data.

Still a Host of Hosts for Wolbachia : Analysis of Recent Data Suggests That 40% of Terrestrial Arthropod Species Are Infected

Biological markets: supply and demand determine the effect of partner choice in cooperation, mutualism and mating

Evolution of cooperation through indirect reciprocity

Genetic and cultural evolution of cooperation