The groups with which we associate influence our actions. This is often the case even when they are not deliberately organised but rather based on social categories, such as sex and skin colour, or cultural homogeneity, such as common language or customs. Group membership can cause widespread phenomena such as ingroup favouritism, polarisation of opinion and competition. Previous experiments have shown that these effects can be triggered by even completely arbitrary distinctions between groups. This thesis uses mathematical models to investigate under what circumstances these phenomena can arise. Using a game theoretical approach, the first three papers address the evolution of ingroup favouritism. Previous models have focused on the prisoners’ dilemma, interactions where the socially optimal behaviour is to co-operate, but where it is in the individual’s self-interest not to. The results presented here suggest that co-ordination problems may have been more important than those of co-operation in the evolution of an ingroup bias. In particular, this applies to common goals that require trust. It is also demonstrated in a behavioural experiment that such trust is most common within groups, but that it can emerge between groups through group reputation. The fourth paper focuses on a model on how cultural groups in contact can develop common norms, rather than polarise into different norm groups, by assuming a confirmation bias. The model is empirically tested on demographic and linguistic data from Mauritian Creole, a natural language developed from the mixing of parent languages. In the fifth paper, the group is defined by common preferences (e.g. for pop songs), which are transmitted in a random copying model. The competitive success of the groups, with respect to their size, is recorded on a toplist, the turnover rate of which is derived. In the final paper, people match up in pairs between groups according to their preferences, and all stable matchings are found under a specific assumption of bounded rationality, when people’s individual behaviour may be affected by the consequences for fellow group members.

Division of labor and division of knowledge are so important and common in society today that it is difficult to imagine a functional society where everyone knows the same things and performs the same tasks. In such a society everyone grows, or gathers, and prepares their own food, makes their own tools, builds their own house, and so on. Cultural evolution is the field of research that studies the creation and diffusion of ideas and societies. It is very uncommon for these studies to take into account the effects of specialization. This thesis will show that specialization is of great importance to cultural evolution. The thesis is divided into two parts: The first is an introduction to studies of specialization and division of labor. The thesis begins with an interdisciplinary survey of the research on division of labor and specialization, including both theoretic and empirical studies. Next is an introduction to modeling specialization and division of labor. This includes a general framework and a number of basic models of different aspects of specialization and division of labor. Part two consists of four papers. The first paper studies the interaction between specialization and cultural cumulation. The second and third papers examine cultural cumulation, specifically the circumstances under which cultural knowledge increases and how cultural knowledge is distributed in the population. The last paper is a mathematical model of how specialization of knowledge (i.e. higher education) leads to social stratification.

This thesis provides an 'immanent' critique of the moral dimension of Hayek's political theory. The concept of morality that Hayek advances is epistemologically founded. That concept is concerned with the recognition and respect of the natural limits of human knowledge and is incompatible with the idea of objective value judgement. The moral dimension of Hayek's theory is based on the methodological implications of his epistemologically founded concept of morality. That dimension consists of the ideas of social spontaneity and cultural evolution and is incompatible with any concept of objective liberal values. The moral dimension of Hayek's theory excludes but also requires substantive politics. The moral exclusion of substantive politics' undermines freedom and equality in catallaxy while, at the same time, it relativises commutative justice and legitimates the minimal state only from the point of view of its legality. Substantive politics is morally required for preserving and promoting institutions such as catallaxy and commutative justice in terms of liberalism. It is argued that the moral exclusion of substantive politics is due to the epistemological premises of Hayek's theory. Those premises form the praxeological presuppositions of social spontaneity and cultural evolution. In terms of them, substantive politics cannot be morally explained. Substantive politics is grounded on a normative/evaluative conception of a social good. That conception depends on critical reason in terms of which objective liberal values can be "recognised and respected. The moral requirement of substantive politics is due to the fact that the process of social spontaneity and cultural evolution cannot by itself be safeguarded against coercion, inequality and injustice.

Human languages are not just tools for transmitting cultural ideas, they are themselves culturally transmitted. This single observation has major implications for our understanding of how and why languages around the world are structured the way they are, and also for how scientists should be studying them. Accounting for the origins of what turns out to be such a uniquely human ability is, and should be, a priority for anyone interested in what makes us different from every other lifeform on Earth. The way the scientific community thinks about language has seen considerable changes over the years. In particular, we have witnessed movements away from a purely descriptive science of language, towards a more explanatory framework that is willing to embrace the difficult questions of not just how individual languages are currently structured and used, but also how and why they got to be that way in the first place. Seeing languages as historical entities is, of course, nothing new in linguistics. Seeing languages as complex adaptive systems, undergoing processes of evolution at multiple levels of interaction however, is. Broadly speaking, this thesis explores some of the implications that this perspective on language has, and argues that in addition to furthering our understanding of the processes of biological evolution and the mechanisms of individual learning required specifically for language, we also need to be mindful of the less well-understood cultural processes that mediate between the two. Human communication systems are not just direct expressions of our genes. Neither are they independently acquired by learners anew at every generation. Instead, languages are transmitted culturally from one generation to another, creating an opportunity for a different kind of evolutionary channel to exist. It is a central aim of this thesis to explore some of the adaptive dynamics that such a cultural channel has, and investigate the extent to which certain structural and statistical properties of language can be directly explained as adaptations to the transmission process and the learning biases of speakers. In order to address this aim, this thesis takes an experimental approach. Building on a rich set of empirical results from various computational simulations and mathematical models, it presents a novel methodological framework for exploring one type of cultural transmission mechanism, iterated learning, in the laboratory using human participants. In these experiments, we observe the evolution of artificial languages as they are acquired and then transmitted to new learners. Although there is no communication involved in these studies, and participants are unaware that their learning efforts are being propagated to future learners, we find that many functional features of language emerge naturally from the different constraints imposed upon them during transmission. These constraints can take a variety of forms, both internal and external to the learner. Taken collectively, the data presented here suggest several points: (i) that iterated language learning experiments can provide us with new insights about the emergence and evolution of language; (ii) that language-like structure can emerge as a result of cultural transmission alone; and (iii) that whilst structure in these systems has the appearance of design, and is in some sense ‘created’ by intentional beings, its emergence is in fact wholly the result of non-intentional processes. Put simply, cultural evolution plays a vital role in language. This work extends our framework for understanding it, and offers a new method for investigating it.

Is it nature or is it nurture? Why Joseph Henrich is unconvinced either category gives a complete picture of human behaviour.

Three different multi-agent models are presented in this thesis, each with a different goal. The first model investigates the possible role migratory routes may have on song evolution and revolution. The second model investigates what social networks could theoretically facilitate song sharing in a population of whales. The third model implements a formal grammar algorithm in order to investigate how the hierarchal structure of the song may affect song evolution. Finally, the thesis attempts to reconnect the models with their origins and discusses how these models could potentially be adapted for composing music. Through the development of these different models, a number of findings are highlighted. The first model reveals that feeding ground sizes may be key locations where song learning from other population may be facilitated. The second model shows that small world social networks facilitate a high degree of agents converging on a single song, similar to what is observed in wild populations. The final model shows that the ability to recognise hierarchy in a sequence coupled with simple production errors, can lead to songs gradually changing over the course of time, while still retaining their hierarchal structure.

Social projection is the tendency to project one's own characteristics onto others. This phenomenon can potentially explain cooperation in prisoner's dilemma experiments and other social dilemmas. The social projection hypothesis has recently been formalized for symmetric games as co-action equilibrium and for general games as consistent evidential equilibrium. These concepts have been proposed to predict choice behavior in experimental one-shot games. We test the predictions of the co-action equilibrium concept in a simple binary minimizer game experiment. We find no evidence of social projection.

A network-based method is developed for analyzing use in stone tool assemblages, where 'use' denotes the tasks for which chipped edges are suitable. Modeling chipped edges as nodes, use-wear and retouch as edge traversals, use-life trajectories of chipped edges as inter-connecting paths, and `tools' as subnetworks over which design tolerances are maintained on edge morphology, the method is an attempt to improve on existing models, allowing for complex, continuous change and multiple uses throughout a chipped edge's use-life. Avoiding analogy-based categories, the method is designed to highlight rather than obscure the possibilities for use and multi-use. Potential for integration into social-learning based models of cultural evolution is considered. The metric is employed to address the widely noted paucity of lithics in Late Prehistoric contexts of the southeastern U.S. Specifically, the Lyon's Bluff site (22OK520, Oktibbeha County, Mississippi) is shown to exhibit substantial use-capacity, suggesting that paucity does not imply divestment.

<p>In this thesis we apply mathematics and formal modeling to study culture from an evolutionary standpoint. Cultural evolution theory is based on the belief that we can increase our understanding of human behavior by studying how culture is created and spread. Together with my co-authors I use mathematical modeling to investigate why we need a theory for cultural evolution, what it can tell us, and how we can test such a theory.</p><p>The thesis consists of an introduction and five papers. The first paper is an empirical test of whether we need to know the history of a population to be able to determine what culture they will have. The second paper looks at the circumstances under which a genetic predisposition for imitating parents could evolve. The third paper looks at the accumulation of neutral traits, that is, cultural variants that flow between people at random without affecting their fitness; neutrality provides an important null hypothesis to other explanations of why we have the culture that we do. The fourth paper makes an attempt at defining what makes a cultural variant successful, and thereby reveals some important differences between genetic and cultural evolution. Finally, the fifth paper investigates a model that can be used to study mechanisms of cultural evolution in laboratory experiments.</p>

In this thesis we apply mathematics and formal modeling to study culture from an evolutionary standpoint. Cultural evolution theory is based on the belief that we can increase our understanding of human behavior by studying how culture is created and spread. Together with my co-authors I use mathematical modeling to investigate why we need a theory for cultural evolution, what it can tell us, and how we can test such a theory. The thesis consists of an introduction and five papers. The first paper is an empirical test of whether we need to know the history of a population to be able to determine what culture they will have. The second paper looks at the circumstances under which a genetic predisposition for imitating parents could evolve. The third paper looks at the accumulation of neutral traits, that is, cultural variants that flow between people at random without affecting their fitness; neutrality provides an important null hypothesis to other explanations of why we have the culture that we do. The fourth paper makes an attempt at defining what makes a cultural variant successful, and thereby reveals some important differences between genetic and cultural evolution. Finally, the fifth paper investigates a model that can be used to study mechanisms of cultural evolution in laboratory experiments.