Fundamental Questions and Perspectives in Cooperation Research

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1 Fundamental Questions and Perspectives in Cooperation Research October 2010 David Skuse, University College London John McNamara, University of Bristol Tamás Székely, University of Bath Ronald Noë, IPHC/CNRS & University of Strasbourg Ruth Mace, University College London INCORE (Integrating Cooperation Research across Europe) Project No A Coordination Action funded for 43 months from 01 March 2007 by the Sixth Framework Programme of the European Commission.

2 Fundamental Questions and Perspectives in Cooperation Research Contents Introduction A Semantic Perspective An Evolutionary Perspective A Social Science Perspective A Game Theory Perspective Integrative Research Themes Human Social Behaviour The Neurobiology of Cooperation Prospects for research References

3 Introduction Evidence for cooperation is apparent throughout the entire history of life on Earth, and extends from humans all the way back to our unicellular ancestors. It is a phenomenon that attracts attention from many different disciplines across the social, life and physical sciences, and is a central focus of enquiry within biology, economics, and political and psychological science. Cooperation has been described as an enduring evolutionary conundrum and the fascination with it owes much to its dualistic nature: cooperating agents have to coordinate in order to obtain a benefit from their interaction, yet they face conflicts over the degree to which each will invest and how much each will extract. The main aim of INCORE (Integrating Cooperation Research across Europe) was to encourage and enable cross-fertilization of different traditions, terminologies and methods, particularly towards the end of furthering our understanding of the biological and cultural evolution (or evolutionary continuity) of cooperative behaviour, and the similarities and differences in the mechanisms and strategies employed by different species towards its generation. Here we outline some of the major research challenges that currently face those working in the field of cooperation today, in the form of summaries from contributions made by INCORE collaborators to a key publication arising from the INCORE consortium (Social Behaviour: Genes, Ecology and Evolution, Székely et al 2010) and Ronald Noë s chapter on Altruism and Cooperation in the 2010 edition of the Encyclopedia of Behavioral Neuroscience. They are all fundamental to our understanding of the evolution of this complex and multifaceted phenomenon. A Semantic Perspective Given the number of disciplines in which cooperation is a central focus of enquiry, a major challenge is to reconcile the different terminology used describe the same phenomena. How do we define terms such as mutualism, or altruism or cooperation in such a way that they mean the same things to anthropologists, or behavioural ecologists, ethologists or economists? A general point that needs to be born in mind is that, depending on one s scientific background, different levels of explanation may be considered more relevant to a discussion of why we cooperate. In psychology and the biological sciences the distinction is made between ultimate and proximate levels of causation, where ultimate causation focuses on explanations relating to the principles of evolution and cultural and natural selection, and proximate causation focuses on explanations relating to external and internal traits and mechanisms. 3

4 Can we generalize key concepts such as cooperative investment or cooperative outcome, by taking an evolutionary perspective? We know that cooperative behaviour evolves because natural selection acts on the consequences of the actions of each agent involved rather than on the interactions themselves. Is it possible to deal with the semantic conundrums posed by cooperation by classifying and describing contrasting instances of cooperation that have resulted from natural and cultural evolution? An Evolutionary Perspective How do we deal with the plethora of theoretical models of cooperation that have little basis in empirical data? How are we going to bring theoretical models and empirical data together? We need to distinguish between evolutionary and culturally determined forms of cooperation. How do we reconcile the fact that evolutionary influences on cooperation can be weak at the level of natural group selection and strong at the level of cultural group selection? Individual selection leads to the survival of packages of genes, in the shape of individual organisms. In the case of many species that cooperate with one another, this phenomenon is driven by sexual reproduction. But where is the place of cultural evolution in this broader picture? Cultural selection acts on information multiplied by communication, and can bring about rapid changes, much more rapid than is possible by conventional evolutionary strategies. What is the status today of the concept of cooperation evolving by group selection? Is this concept still a valid one? In evolutionary biology, group selection refers to the idea that alleles can become fixed or spread in a population because of the benefits they bestow on groups, regardless of the alleles' effect on the fitness of individuals within that group. How relevant are models of individual selection, an evolutionary mechanism that was thought to be a far more salient influence on development than selection at the group level, in recent years? A Social Science Perspective Why is cooperation between groups of individuals so common in human societies, but so rare among other animals? How did humans learn to develop unique forms of cooperation in the form of collective actions between large numbers of unrelated individuals? 4

5 How was it that humans evolved mechanisms of cooperation between individuals that have a rigid hierarchical structure? By what means did humans develop the capacity to build groups that can cooperate to form stable peaceful societies of many thousands, or armies of similar size, yet allow considerable flexibility of behaviour at the level of the individual? What is the meaning of the term social dilemma and is it a peculiarly human characteristic? Some forms of cooperation are very unstable, but the fact that humans can solve at least some social dilemmas is a characteristic that defines human existence in a way that sets it apart from other social species. Is our capacity to develop patterns of cooperation that are uniquely human related to our ability to use language, or to act with foresight, or to sustain attention, or shift our focus of interest from one issue to another with ease, or our theory of mind? What empirical studies could address these questions? A Game Theory Perspective Game theory can be used to characterize the eventually stable endpoints of the evolutionary process. It entails the concept of an evolutionarily stable strategy, which would be regarded as resident if adopted by all members of a population. If truly stable, then no mutant strategy can invade the resident strategy (the so-called Nash equilibrium). But, in the instance of human decision-making, are our decisions always guided by rational deliberations? Although there was a time when humans were thought to act rationally, in economic terms, the empirical evidence did not support this hypothesis. There is increasing evidence that simple games designed to model cooperation should not be considered in isolation. When we are developing theoretical structures that are based on game theory, we must not consider components in isolation. We need to be aware that payoffs in one component are determined by what is going on in other components. Accordingly, we need to develop ways of modelling all feedbacks and links, in the same analysis. We may choose a partner with whom to interact on the basis of that individuals past behaviour. On the other hand, prolonged observations are potentially costly and may reveal nothing of value. Are such observations only worthwhile if there is substantial variation in the trait of interest within the population observed? How do we best handle a situation where an individual is uncooperative? If we break up a partnership in order to seek a more cooperative partner, because our current partner is insufficiently cooperative, we will want to make sure there is potentially a more cooperative partner elsewhere. Individual variability 5

6 is a critical and somewhat neglected aspect of cooperation. Arising from the need to take into account variability in the characteristics of a population s behaviour, is the observation that some individuals will tend to behave exceptionally consistently because of their personality. There will be stable individual differences, at least in some members of a group, which should be taken into account in Game-Theoretic models because they may not always be adaptive. How to allow for these individual differences is another challenge to cooperation research. Integrative Research Themes These descriptions aggregate research challenges from the various perspectives above into broad integrative themes. Human Social Behaviour Employing the concepts of behavioural ecology, and the theoretical framework of social evolution, we can address key questions in the evolution of human social behaviour. These include: What were our ancestors like? Did we breed cooperatively? How has our social evolution contributed to our life-history evolution? Further questions also need to be answered. For example, why is there diversity in human cultural norms between societies, especially in marriage and kinship systems, and diversity in social norms relating to fairness and levels of trust? What evolutionary mechanisms underpin the unique abilities of humans to coordinate actions between large numbers of only distantly related individuals, individual natural selection or group-level cultural selection? This is far from an exhaustive list of topics in a huge field, but these have been selected because they all illustrate examples of human behaviours that have at least some uniquely human characteristics. There is an ongoing debate about how humans form much larger groups, including ethno-linguistic groups of many hundreds or thousands of unrelated individuals. Whilst there is no doubt that we do this, whether the behaviour is an emergent property of strategic decision rules selected for at the level of the individual, or the result of some form of multi-level selective forces, remains a matter of debate. We are exquisitely social. We live not only with our families but invariably in larger social networks. Why did social emotions such as the ability to cooperate, or a sense of fairness, evolve? Was it in the context of conflict, of warfare between disparate groups who wanted to acquire territory, or mates, or food and other property? These are still open questions, which may have relevance to how we manage economic behaviour today. 6

7 The Neurobiology of Cooperation Human social behaviour is wonderfully complex, and influenced by genetic, environmental and cultural influences. Cooperative behaviour is one aspect of human social behaviour, and it is sensitive to the neural processes underlying social cognition. Human social cognition, or the ability to process social information thus influencing human social behaviour, is a broad and complex concept, as yet not defined unambiguously. We are learning more, year on year, about the basic neural processes underlying human social cognition, and the genetic and molecular influences that may shape behavioural variation between individuals. Within the very near future, we will be able to describe the neural circuits in the brain underlying social cognition, particularly with reference to self-knowledge and the concept of theory of mind the ability to think about things from the perspective of another person. Cellular aspects of social cognition, although still unclear, have been explored in relation to the putative role of mirror neurons. The role of mirror neurons in our understanding of other people s thoughts and feelings is still debated; their importance in human cooperation is uncertain. The neurobiology of attachment underlying social relationships has relevance to our understanding of the molecular underpinnings of social cognition. There is burgeoning interest in the neuropeptides: oxytocin and vasopressin. Oxytocin and vasopressin are nonapeptides that have been increasingly identified as playing a pivotal role in social cognition. Animal studies have highlighted the role of these peptides in social roles as diverse as parenting behaviour, social recognition and affiliative behaviours. Another theme, that will have increasing importance in the future discussion of cooperative behaviour, comes from animal studies. These have shown unequivocally that the processes of social cognition are supported by reward circuitry, underpinned by the dopaminergic neurotransmitter system in the brain. Reward processes appear to reinforce bonds, both parental and for mating purposes, and possibly also the rewarding aspects of human social interactions, trust and altruism. Prospects for research Early behavioural ecologists focused almost exclusively on the adaptive value of behaviour. The role played by genetic variation, influencing behaviour, was not taken into account sufficiently: the role played by a parent, influencing their offspring s reproductive success was not prominent in the theoretical models of that time. 7

8 We now realize that we should take into account a variety of proximal biological influences on behavioural adaptation. These include not only genetic variation but hormonal factors, physiological variables and others. We may also have to take into account the role of the environment upon genetic function so-called epigenetic influences. How do we model social behaviour together with an array of potential biological and environmental influences? Simply knowing the constituent parts is insufficient. We need to understand how those constituents combine together to form a complex phenotype or measureable outcome in this case, cooperative behaviour. In the coming years, how are we going to develop a vision for the systems biology of behaviour? We have a burgeoning of approaches based in biology, at the level of genomics, proteomics, metabolomics and so on. We may even be able to develop at this early stage, some simple definitions of how cells function as a consequence of these integrated systems. But when we move beyond the cell to the complex of systemic interactions that underlie even simple behaviours we are still lacking a conceptual framework. Perhaps behaviour, especially social behaviour, is most appropriately viewed as emerging from the interactions of many component parts which combine in complex ways, at another level of understanding. We may be able to define the components with increasing clarity, but the effect of their combination is perhaps conceptualized in an entirely different way. We can define processes at a biological or genetic level that contribute to cooperation, but the emergent properties of the organism s cooperative behaviour, arising from those individual processes, are not entirely definable as the sum of its parts. 8

9 References Louise Gallagher and David Skuse (2010) Molecular and genetic influences on the neural substrate of social cognition in humans. In Social Behaviour: Genes, Ecology and Evolution. Edited by Tamás Székely, Allen J. Moore and Jan Komdeur. Cambridge University Press. ISBN Ruth Mace (2010) Social behavior in humans. In Social Behaviour: Genes, Ecology and Evolution. Edited by Tamás Székely, Allen J. Moore and Jan Komdeur. Cambridge University Press. ISBN John M McNamara and Franz J. Weissing (2010) Evolutionary game theory.. In Social Behaviour: Genes, Ecology and Evolution. Edited by Tamás Székely, Allen J. Moore and Jan Komdeur. Cambridge University Press. ISBN Allen J. Moore, Tamas Szekely and Jan Komdeur (2010) Prospects for research in social behaviour: systems biology meets behaviour. In Social Behaviour: Genes, Ecology and Evolution. Edited by Tamás Székely, Allen J. Moore and Jan Komdeur. Cambridge University Press. ISBN Ronald Noë (2010) Altruism and cooperation. In Encyclopedia of Behavioral Neuroscience Edited by George F. Koob, Michel Le Moal and Richard F. Thompson Elsevier Ltd. ISBN: Tamás Székely, Allen J. Moore and Jan Komdeur (eds.) (2010) Social Behaviour: Genes, Ecology and Evolution. Cambridge University Press. ISBN