The Center for the Dynamics of Social Complexity and Exeter is happy to announce a series of free webinars for Fall 2021 on Evolution and Social Systems. This series is a continuation of the past semester seminars: DySoC/NIMBioS Webinar Series on Cultural Evolution and DySoC/NIMBioS Webinar Series on Human Origins and Cultural Evolution.
Co-organizer: Peter J. Richerson (University of California, Davis)
Human social systems are extraordinarily complex and diverse. Around the world are organized into different societies that are structured and by a variety of different institutions, social norms, beliefs, languages, and other aspect of culture. Understanding how societies function and why societies are the way they are, are topics of interest to a wide variety of different academic disciplines. Evolutionary thinking can help bring together the insights from different disciplines and approaches, and can play an important role in understanding the similarities and differences between human societies and those of other species, the ways that different environmental contexts present different challenges that societies have adapted to, how and why culture and societies change over time, and how different cultural histories have shaped the world we live in today. In this interdisciplinary seminar series we present talks from a variety of researchers, including anthropologists, archaeologists, behavioural ecologists, economists, psychologists, and sustainability scientists. As many of the talks will illustrate, this work is not only of academic interest but is increasingly important in addressing some of the biggest social and ecological challenges we face in the world today.
Speaker: Simon Levin (Ecology & Evolutionary Biology, Princeton University)
Topic: Public goods and environmental challenges: Learning from evolution
Abstract: Ecological and economic systems are alike in that individual agents compete for limited resources, evolve their behaviors in response to interactions with others, and form exploitative as well as cooperative interactions as a result. In these complex adaptive systems, macroscopic properties like the flow patterns of resources like nutrients and capital emerge from large numbers of microscopic interactions, and feed back to affect individual behaviors. In this talk, I will explore some common features of these systems, especially as they involve the evolution of cooperation in dealing with public goods, common pool resources and collective movement. I will describe examples from bacteria and slime molds to vertebrate groups to insurance arrangements in human societies and international agreements on environmental issues. These present mathematical challenges including scaling from the microscopic to the macroscopic, the emergence of pattern, critical transitions and conflicts between the interests of individuals and the good of collectives.
Speaker: Nathan Nunn (Frederic E. Abbe Professor of Economics, Harvard University)
Abstract: The presentation will be an overview of recent empirical research by the author on the nature of cultural persistence and change. Particular attention will be paid to the interplay between culture, institutions, and policies both historically and today and the implications of this for contemporary economic success and economic crisis.
Speaker: Kristen Hawkes (Anthropology Department, University of Utah)
Topic: Sexual selection, carnivory, and life history evolution in the human radiation
Claims that paternal provisioning is the fitness payoff for big game hunting and aggressive scavenging are a cornerstone of the hunting hypothesis about the evolution of our genus. But challenges to those claims are substantial making the deep archaeological record of human carnivory a puzzle. An answer that aligns with Darwin’s insights about the importance of sexual selection in human evolution comes from a grandmother hypothesis about the evolution of human postmenopausal longevity. As lifespans increased in our radiation, more seniors biased the mating sex ratio toward males. More males in the mating pool shifted paternity winnings to those successful at guarding a mate. If success depended on others’ deference, Darwin’s surmise in Descent is directly relevant. He said ancestral males likely earned admiration by displaying courage and pugnacity. Exactly those qualities would be on display in dangerous contests with big carnivores for large carcasses. If risks of substantial harm gained deference for proprietary mating claims, the carnivory in early Pleistocene archaeology is a record of male mating competition.
Sexual selection, carnivory, and life history evolution in the human radiation
Speaker: Kristen Hawkes (Anthropology Department, University of Utah)
Topic: Sexual selection, carnivory, and life history evolution in the human radiation
Abstract: Claims that paternal provisioning is the fitness payoff for big game hunting and aggressive scavenging are a cornerstone of the hunting hypothesis about the evolution of our genus. But challenges to those claims are substantial making the deep archaeological record of human carnivory a puzzle. An answer that aligns with Darwin’s insights about the importance of sexual selection in human evolution comes from a grandmother hypothesis about the evolution of human postmenopausal longevity. As lifespans increased in our radiation, more seniors biased the mating sex ratio toward males. More males in the mating pool shifted paternity winnings to those successful at guarding a mate. If success depended on others’ deference, Darwin’s surmise in Descent is directly relevant. He said ancestral males likely earned admiration by displaying courage and pugnacity. Exactly those qualities would be on display in dangerous contests with big carnivores for large carcasses. If risks of substantial harm gained deference for proprietary mating claims, the carnivory in early Pleistocene archaeology is a record of male mating competition.
Speaker: Giulia Andrighetto (Institute of Cognitive Sciences and Technologies (ISTC) at CNR, Malardalen University, Vasteras, Sweden)
Topic: Norm change and cooperation under collective risk in a long-term experiment
Abstract: Social norms are a crucial part of the solution to our most pressing societal challenges, from mitigating climate change to reducing the spread of infectious diseases. Despite their relevance, how norms shape cooperation among strangers is still insufficiently understood. Influential theories suggest that the level of exogenous threats faced by different societies plays a key role in the strength of the norms that different cultures have evolved. Still causal evidence of exogenous threats on norms has not been so far collected. Here we deal with this dual challenge using a 30-day collective-risk social dilemma experiment to observe and measure norm change in a controlled setting. We ask whether a looming but uncertain collective catastrophe changes the strength of the social norms of cooperation that may avert it. We find that social norms predict cooperation and causally affect behavior. We also provide the first empirical demonstration that higher risk spontaneously lead to stronger social norms and that, when the risk changes, stronger social norms are more resistant to erosion. Still, the foreseeable loosening of norms in low risk settings has important policy implications. Taken together, our results demonstrate the causal effect of social norms in promoting cooperation and their role in making behavior resilient in the face of exogenous change.
Speaker: Anne C. Pisor (Department of Anthropology, Washington State University)
Topic: Long-distance social connections, collective-action problems, and climate-change adaptation
Abstract: Humans are group-living and find groups highly salient, so unsurprisingly much of the focus in the evolutionary human sciences has been on intergroup competition and parochialism. However, this overlooks the flexibility of human relationships that span group boundaries or span distance; when present, these can have profound effects on the structure and information transmission of social networks. In this talk, I'll provide an overview of my work on long-distance social connections and their relevance for studying two of the most pressing issues of the 21st century: sustainable resource management and climate change. First, large common-pool resources, like fisheries and forests, are difficult to manage because so many communities can access them. Can connections between communities help us predict when management will be successful? Second, humans have a long history of adaptation to climate change, and many of these climate-change adaptations were and are cultural. Studying contemporary peoples, how does cultural adaptation to climate change alter social networks, and how do these changes to networks alter the transmission of climate-change adaptations in turn? I conclude by highlighting future directions for research on long-distance connections, both in the theoretical and applied domains, and where my lab is headed next.
Speaker: Timothy Njagi (Tegemeo Institute of Agricultural Policy and Development, Egerton University, Kenya)
Topic: A comparative perspective on the evolution and sustainability of pastoralist production systems
Abstract: Pastoral communities worldwide occupy areas that are vast and primarily considered marginal lands. These lands are characterised by arid and semi-arid conditions such as high temperatures and low rainfall. Primarily, communities practise extensive livestock production systems that are adaptable to these conditions. Traditionally, pastoral communities have accessed and managed these lands collectively, under customary systems. However, public policy has not always supported land access and utilisation systems used by pastoral communities. Over the years, pastoralism has been perceived as backward, contributing to environmental degradation, and inefficient land use. Government programs favouring land intensification are being pushed in pastoral areas despite evidence of their effectiveness, especially on productive and livelihood support systems. This is a result of misconceptions about pastoralism as a productive system. We compare the evolution of land tenure systems and their effect on pastoralists production systems in East African and Latin America, two continents with significant pastoralists communities where cultural identity is strong, community systems still exist, and both face similar pressures on their livelihoods. The objective is to learn how the evolution of land tenure systems in pastoral areas has impacted the sustainability of pastoralists production systems and draw lessons from these communities to facilitate policies that improve the social and economic status of pastoral communities.
Speaker: Monique Borgerhoff Mulder (MPI-EVA Leipzig, UC Davis, Santa Fe Institute)
Topic: How Many Wives? Tracing the Interdisciplinary Career of the Polygyny Threshold Model
Abstract: Human behavioural ecologists take, as a starting point, models derived from the study of the social behaviour of non-human animals, but as the field matures there are emerging deep intersections with other disciplines, particularly anthropology, economics and policy. I illustrate this through a history of the study of polygynous marriage, starting with the polygyny threshold model, its applications within the anthropological literature, and the import of this work for explaining the distribution of polygyny globally. These findings both complement and contrast with those of economists, and have implications for an understanding of the historical origins of monogamy, for understanding patterns of female cooperation and competition, and for the legitimacy of current policies calling for outlawing polygynous marriage. I end with a prospective review of how such models can be tweaked to answer the parallel question of “How many husbands?”, an as yet relatively underdeveloped area of investigation in the human evolutionary sciences.
Speaker: Stefani Crabtree (Assistant Professor in Social-Environmental Modeling, Department of Environment and Society, College of Natural Resources, Utah State University & Santa Fe Institute)
Topic: Modern Lessons of applying Socio-Environmental Modeling to the Archaeological Record
Abstract: Archaeology provides rich data of the past 60,000 years of human-environment interaction, yet it remains under-utilized for examining present ecosystems. However, modern methods can harness the explanatory power of the past to calibrate our understanding of the present and predict how we will face challenges in the future. In this vein approaches from complex adaptive systems science including agent-based modeling and network science prove particularly promising. By simulating societies in silico agent-based models and networks have enabled researchers to not only understand previously intractable aspects of the past, but also to use these simulations to predict what can make resilient societies and what lead them toward vulnerabilities to external perturbations. My work has used agent-based modeling, social network analysis, and trophic network analysis (or food web modeling) to examine robustness and vulnerabilities of societies from the American Southwest, to northern Mongolia, to Aboriginal Australia. In this talk I explore the unique ways that socio-environmental modeling can help us understand the lifeways of societies worldwide, and also suggest that understanding how people interacted in their uniquely challenging environments can provide parallels to understanding humanity’s position in ecosystems today. Only through applying a complexity lens can we truly understand how the actions and interactions of people led to the large overarching structures we see today.
Speaker: Matthijs van Veelen (Evolution and Behaviour at CREED, University of Amsterdam, Netherlands)
Topic: The evolution of morality and the role of commitment
A considerable share of the literature on the evolution of human cooperation considers the question why we have not evolved to play the Nash equilibrium in prisoners' dilemmas or public goods games. In order to understand human morality and pro-social behaviour, we suggest it would actually be more informative to investigate why we have not evolved to play the subgame perfect Nash equilibrium in sequential games, such as the ultimatum game and the trust game. The "rationally irrational" behavior that can evolve in such games gives a much better match with actual human behaviour, including elements of morality such as honesty, responsibility, and sincerity, as well as the more hostile aspects of human nature, such as anger and vengefulness. The mechanism at work here is commitment, which does not need population structure, nor does it need interactions to be repeated. We argue that this shift in focus can not only help explain why humans have evolved to know wrong from right, but also why other animals, with similar population structures and similar rates of repetition, have not evolved similar moral sentiments. The suggestion that the evolutionary function of morality is to help us commit to otherwise irrational behaviour stems from the work of Robert Frank, which has played a surprisingly modest role in the scientific debate to date.
Speaker: Heidi Colleran (Max Planck Institute for Evolutionary Anthropology Department of Human Behavior, Ecology and Culture)
Topic: The impossibility of "natural fertility" in human cultural systems
Speaker: Naoko Matsumoto (Director of the Research Institute for the Dynamics of Civilizations, Department of Archaeology, Okayama University)
Topic: What’s so special about the Jomon?
Abstract: The Jomon is defined as a period of hunter-gatherers with pottery on the Japanese Archipelago and spans approximately 13,000 years. The Jomon is well known as a sedentary hunter-gatherer society with the rich material culture of pottery and clay figurines. Still, there was a great deal of regional diversity, and dynamic socio-cultural changes can be seen. In this talk, I will give an overview of the characteristics of the Jomon period, taking into account the latest research trends on subsistence and material culture. Research, Okayama University
DySoC is affiliated with The University of Tennessee, Knoxville