1
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Gross J, Méder ZZ, Romano A, De Dreu CKW. Indirect reciprocity can foster large-scale cooperation. Proc Natl Acad Sci U S A 2024; 121:e2409894121. [PMID: 38913888 DOI: 10.1073/pnas.2409894121] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/26/2024] Open
Affiliation(s)
- Jörg Gross
- Department of Psychology, University of Zurich, Zurich 8050, Switzerland
| | - Zsombor Z Méder
- Faculty of Economics and Business, Groningen University, Groningen 9700AB, the Netherlands
| | - Angelo Romano
- Department of Psychology, Leiden University, Leiden 2333AK, the Netherlands
| | - Carsten K W De Dreu
- Faculty of Economics and Business, Groningen University, Groningen 9700AB, the Netherlands
- Faculty of Behavioral and Social Sciences, University of Groningen, Groningen 9712TS, the Netherlands
- Behavioral Ecology and Sociobiology Unit, German Primate Center, Leibniz Institute for Primate Research, Göttingen 37077, Germany
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2
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Arseneau-Robar TJ, Teichroeb JA, Macintosh AJJ, Saj TL, Glotfelty E, Lucci S, Sicotte P, Wikberg EC. When population growth intensifies intergroup competition, female colobus monkeys free-ride less. Sci Rep 2024; 14:14363. [PMID: 38906888 PMCID: PMC11192885 DOI: 10.1038/s41598-024-64188-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2023] [Accepted: 06/06/2024] [Indexed: 06/23/2024] Open
Abstract
Intergroup aggression often results in the production of public goods, such as a safe and stable social environment and a home range containing the resources required to survive and reproduce. We investigate temporal variation in intergroup aggression in a growing population of colobus monkeys (Colobus vellerosus) to ask a novel question: "Who stepped-up to produce these public goods when doing so became more difficult?". Both whole-group encounters and male incursions occurred more frequently as the population grew. Males and females were both more likely to participate in whole-group encounters when monopolizable food resources were available, indicating both sexes engaged in food defence. However, only females increasingly did so as the population grew, suggesting that it was females who increasingly produced the public good of home range defence as intergroup competition intensified. Females were also more active in male incursions at high population densities, suggesting they increasingly produced the public good of a safe and stable social environment. This is not to say that males were chronic free-riders when it came to maintaining public goods. Males consistently participated in the majority of intergroup interactions throughout the study period, indicating they may have lacked the capacity to invest more time and effort.
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Affiliation(s)
| | - Julie A Teichroeb
- Department of Anthropology, University of Toronto Scarborough, Toronto, Canada
| | | | - Tania L Saj
- Department of Anthropology, University of Calgary, Calgary, Canada
| | - Emily Glotfelty
- Department of Anthropology, University of Texas San Antonio, San Antonio, USA
| | - Sara Lucci
- Department of Anthropology, University of Texas San Antonio, San Antonio, USA
| | - Pascale Sicotte
- Department of Biology, Concordia University, Montreal, QC, Canada
| | - Eva C Wikberg
- Department of Anthropology, University of Texas San Antonio, San Antonio, USA.
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3
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Camerlenghi E, Nolazco S, Farine DR, Magrath RD, Peters A. Social restructuring during harsh environmental conditions promotes cooperative behaviour in a songbird. Proc Biol Sci 2024; 291:20232427. [PMID: 38628131 PMCID: PMC11022012 DOI: 10.1098/rspb.2023.2427] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2023] [Accepted: 03/13/2024] [Indexed: 04/19/2024] Open
Abstract
Cooperation may emerge from intrinsic factors such as social structure and extrinsic factors such as environmental conditions. Although these factors might reinforce or counteract each other, their interaction remains unexplored in animal populations. Studies on multilevel societies suggest a link between social structure, environmental conditions and individual investment in cooperative behaviours. These societies exhibit flexible social configurations, with stable groups that overlap and associate hierarchically. Structure can be seasonal, with upper-level units appearing only during specific seasons, and lower-level units persisting year-round. This offers an opportunity to investigate how cooperation relates to social structure and environmental conditions. Here, we study the seasonal multilevel society of superb fairy-wrens (Malurus cyaneus), observing individual responses to experimental playback of conspecific distress calls. Individuals engaged more in helping behaviour and less in aggressive/territorial song during the harsher non-breeding season compared to the breeding season. The increase in cooperation was greater for breeding group members than for members of the same community, the upper social unit, comprised of distinct breeding groups in association. Results suggest that the interaction between social structure and environmental conditions drives the seasonal switch in cooperation, supporting the hypothesis that multilevel societies can emerge to increase cooperation during harsh environmental conditions.
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Affiliation(s)
- Ettore Camerlenghi
- School of Biological Sciences, Monash University, Wellington Road, Clayton, Victoria, Australia
- Department of Behavioural Ecology, Bielefeld University, 33615 Bielefeld, Germany
| | - Sergio Nolazco
- School of Biological Sciences, Monash University, Wellington Road, Clayton, Victoria, Australia
| | - Damien R. Farine
- Department of Evolutionary Biology and Environmental Studies, University of Zurich, 8057 Zürich, Switzerland
- Department of Collective Behavior, Max Planck Institute of Animal Behavior, 78464 Konstanz, Germany
- Division of Ecology and Evolution, Research School of Biology, Australian National University, 46 Sullivan's Creek Road, Canberra 2600, Australia
| | - Robert D. Magrath
- Division of Ecology and Evolution, Research School of Biology, Australian National University, 46 Sullivan's Creek Road, Canberra 2600, Australia
| | - Anne Peters
- School of Biological Sciences, Monash University, Wellington Road, Clayton, Victoria, Australia
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4
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Meijer H. Janus faced: The co-evolution of war and peace in the human species. Evol Anthropol 2024:e22027. [PMID: 38623594 DOI: 10.1002/evan.22027] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2023] [Revised: 03/22/2024] [Accepted: 03/25/2024] [Indexed: 04/17/2024]
Abstract
The human species presents a paradox. No other species possesses the propensity to carry out coalitionary lethal attacks on adult conspecifics coupled with the inclination to establish peaceful relations with genetically unrelated groups. What explains this seemingly contradictory feature? Existing perspectives, the "deep roots" and "shallow roots" of war theses, fail to capture the plasticity of human intergroup behaviors, spanning from peaceful cooperation to warfare. By contrast, this article argues that peace and war have both deep roots, and they co-evolved through an incremental process over several million years. On the one hand, humans inherited the propensity for coalitionary lethal violence from their chimpanzee-like ancestor. Specifically, having first inherited the skills to engage in cooperative hunting, they gradually repurposed such capacity to execute coalitionary killings of adult conspecifics and subsequently enhanced it through technological innovations like the use of weapons. On the other hand, they underwent a process of cumulative cultural evolution and, subsequently, of self-domestication which led to heightened cooperative communication and increased prosocial behavior within and between groups. The combination of these two biocultural evolutionary processes-coupled with feedback loop effects between self-domestication and Pleistocene environmental variability-considerably broadened the human intergroup behavioral repertoire, thereby producing the distinctive combination of conflictual and peaceful intergroup relations that characterizes our species. To substantiate this argument, the article synthesizes and integrates the findings from a variety of disciplines, leveraging evidence from evolutionary anthropology, primatology, archeology, paleo-genetics, and paleo-climatology.
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Affiliation(s)
- Hugo Meijer
- Sciences Po, Center for International Studies (CERI), Paris, France
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5
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Kandza VH, Jang H, Kiabiya Ntamboudila F, Lew-Levy S, Boyette AH. Dyadic inter-group cooperation in shotgun hunting activities in a Congo Basin village. EVOLUTIONARY HUMAN SCIENCES 2024; 6:e22. [PMID: 38689891 PMCID: PMC11058523 DOI: 10.1017/ehs.2024.14] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2023] [Revised: 02/19/2024] [Accepted: 03/13/2024] [Indexed: 05/02/2024] Open
Abstract
Understanding the dynamics of inter-group cooperation in human adaptation has been the subject of recent empirical and theoretical studies in evolutionary anthropology, beginning to fill gaps in our knowledge of how interactions across political, economic and social domains can - and often do - lead to stable, large-scale cooperation. Here we investigate dyadic intergroup cooperation in shotgun hunting in the Republic of the Congo. In the Congo Basin, inter-group cooperation between foragers and farmers is at the centre of an exchange system maintained by traditional norms and institutions such as fictive kinship. Here, we focused on what factors predict cooperative shotgun hunting exchanges between BaYaka and Yambe. We conducted structured interviews with 48 BaYaka hunters and 18 Yambe men who organise hunts in a village along the Motaba River. We used Bayesian multilevel regression models to investigate the influence of Yambe and BaYaka attributes on probability of dyadic cooperation. We found that BaYaka men's reputations as skilled hunters and their family size each predicted cooperation in shotgun hunting, whereas there was no effect of Yambe attributes (status, wealth, family size). We discuss the results in terms of evolutionary models of men as hunters and inter-group cooperation, as well as biodiversity conservation implications.
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Affiliation(s)
- Vidrige H. Kandza
- Department of Human Behavior, Ecology and Culture Max Planck Institute for Evolutionary Anthropology, Leipzig, Germany
| | - Haneul Jang
- Department of Human Behavior, Ecology and Culture Max Planck Institute for Evolutionary Anthropology, Leipzig, Germany
- Institute for Advances Studies, Toulouse, France
| | - Francy Kiabiya Ntamboudila
- Faculte des Lettres, Arts et Sciences Humaines Marien Ngouabi University, Brazzaville, Republic of the Congo
| | | | - Adam H. Boyette
- Department of Human Behavior, Ecology and Culture Max Planck Institute for Evolutionary Anthropology, Leipzig, Germany
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6
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De Dreu CKW, Gross J, Romano A. Group Formation and the Evolution of Human Social Organization. PERSPECTIVES ON PSYCHOLOGICAL SCIENCE 2024; 19:320-334. [PMID: 37450408 PMCID: PMC10913362 DOI: 10.1177/17456916231179156] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 07/18/2023]
Abstract
Humans operate in groups that are oftentimes nested in multilayered collectives such as work units within departments and companies, neighborhoods within cities, and regions within nation states. With psychological science mostly focusing on proximate reasons for individuals to join existing groups and how existing groups function, we still poorly understand why groups form ex nihilo, how groups evolve into complex multilayered social structures, and what explains fission-fusion dynamics. Here we address group formation and the evolution of social organization at both the proximate and ultimate level of analysis. Building on models of fitness interdependence and cooperation, we propose that socioecologies can create positive interdependencies among strangers and pave the way for the formation of stable coalitions and groups through reciprocity and reputation-based partner selection. Such groups are marked by in-group bounded, parochial cooperation together with an array of social institutions for managing the commons, allowing groups to scale in size and complexity while avoiding the breakdown of cooperation. Our analysis reveals how distinct group cultures can endogenously emerge from reciprocal cooperation, shows that social identification and group commitment are likely consequences rather than causes of group cooperation, and explains when intergroup relations gravitate toward peaceful coexistence, integration, or conflict.
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Affiliation(s)
| | - Jörg Gross
- Department of Psychology, University of Zurich
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7
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Mörchen J, Luhn F, Wassmer O, Kunz JA, Kulik L, van Noordwijk MA, Rianti P, Rahmaeti T, Utami Atmoko SS, Widdig A, Schuppli C. Orangutan males make increased use of social learning opportunities, when resource availability is high. iScience 2024; 27:108940. [PMID: 38333693 PMCID: PMC10850741 DOI: 10.1016/j.isci.2024.108940] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2023] [Revised: 12/05/2023] [Accepted: 01/15/2024] [Indexed: 02/10/2024] Open
Abstract
Humans' colonization of diverse habitats relied on our ancestors' abilities to innovate and share innovations with others. While ecological impacts on innovations are well studied, their effect on social learning remains poorly understood. We examined how food availability affects social learning in migrant orangutan unflanged males, who may learn from local orangutans through peering (i.e., observational social learning). We analyzed 1,384 dyadic associations, including 360 peering events, among 46 wild Sumatran orangutan and 25 Bornean orangutan males, collected over 18 years. Migrants' peering rates significantly increased with higher food availability and time spent in proximity to others. Furthermore, migrants in the more sociable Sumatran population exhibited significantly higher peering rates compared to the Borneans, suggesting intrinsic and/or developmental effects of food availability on social learning. These findings emphasize the importance of investigating ecological effects on social learning on the immediate, developmental, and intrinsic levels for our understanding of cultural evolution.
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Affiliation(s)
- Julia Mörchen
- Development and Evolution of Cognition Research Group, Max Planck Institute of Animal Behavior, 78467 Konstanz, Germany
- Behavioral Ecology Research Group, Institute of Biology, University of Leipzig, 04103 Leipzig, Germany
- Department of Primate Behaviour and Evolution, Max Planck Institute for Evolutionary Anthropology, 04103 Leipzig, Germany
| | - Frances Luhn
- Behavioral Ecology Research Group, Institute of Biology, University of Leipzig, 04103 Leipzig, Germany
| | - Olivia Wassmer
- Department of Evolutionary Anthropology, University of Zurich, 8057 Zurich, Switzerland
| | - Julia A. Kunz
- Department of Evolutionary Anthropology, University of Zurich, 8057 Zurich, Switzerland
- Institute of Evolutionary Biology of Montpellier (ISEM), University of Montpellier, CNRS, IRD, 34095 Montpellier, France
| | - Lars Kulik
- Behavioral Ecology Research Group, Institute of Biology, University of Leipzig, 04103 Leipzig, Germany
| | - Maria A. van Noordwijk
- Department of Evolutionary Anthropology, University of Zurich, 8057 Zurich, Switzerland
- Comparative Socioecology, Max Planck Institute of Animal Behavior, 78467 Konstanz, Germany
| | - Puji Rianti
- Primate Research Center, Institute of Research and Community Service, IPB University, Bogor 16680, Indonesia
- Animal Biosystematics and Ecology Division, Department of Biology, IPB University, Bogor 16680, Indonesia
| | - Tri Rahmaeti
- Department of Biology, Graduate Program, Faculty of Biology and Agriculture, Universitas Nasional, Jakarta 12520, Indonesia
| | - Sri Suci Utami Atmoko
- Department of Biology, Graduate Program, Faculty of Biology and Agriculture, Universitas Nasional, Jakarta 12520, Indonesia
| | - Anja Widdig
- Behavioral Ecology Research Group, Institute of Biology, University of Leipzig, 04103 Leipzig, Germany
- Department of Primate Behaviour and Evolution, Max Planck Institute for Evolutionary Anthropology, 04103 Leipzig, Germany
- German Centre for Integrative Biodiversity Research (iDiv), Halle-Jena-Leipzig, 04103 Leipzig, Germany
| | - Caroline Schuppli
- Development and Evolution of Cognition Research Group, Max Planck Institute of Animal Behavior, 78467 Konstanz, Germany
- Department of Evolutionary Anthropology, University of Zurich, 8057 Zurich, Switzerland
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8
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Majolo B. The intertwined nature of peace and war. Behav Brain Sci 2024; 47:e17. [PMID: 38224057 DOI: 10.1017/s0140525x23002583] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2024]
Abstract
Glowacki discusses how humans regularly face collective action problems that may result in either peaceful or aggressive between-group interactions. Peace and war probably coevolved in humans. Using a gene-culture evolutionary framework is a powerful way to analyse why, when, and how humans have the capacity to build and maintain long-term peaceful interactions between groups and also to wage deadly wars.
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Affiliation(s)
- Bonaventura Majolo
- School of Psychology, University of Lincoln, Lincoln, UK ; https://staff.lincoln.ac.uk/bmajolo
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9
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Pisor AC, Smith KM, Deminchuk JP. The evolution of (intergroup) peace hinges on how we define groups and peace. Behav Brain Sci 2024; 47:e22. [PMID: 38224125 DOI: 10.1017/s0140525x23002649] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2024]
Abstract
Glowacki defines peace as harmonious relationships between groups maintained without the threat of violence, where groups can be anything from families to nation states. However, defining such contentious concepts like "peace" and "groups" is a difficult task, and we discuss the implications of Glowacki's definitions for understanding intergroup relationships and their evolutionary history.
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Affiliation(s)
- Anne C Pisor
- Department of Anthropology, Washington State University, Pullman, WA, USA ://www.kristophermsmith.com/
- Department of Human Behavior, Ecology, and Culture, Max Planck Institute for Evolutionary Anthropology, Leipzig, Germany
| | - Kristopher M Smith
- Department of Anthropology, Washington State University, Pullman, WA, USA ://www.kristophermsmith.com/
| | - Jeffrey P Deminchuk
- School of Politics, Philosophy, and Public Affairs, Washington State University, Pullman, WA, USA ://socialitylab.org
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10
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Waring TM, Wood ZT, Szathmáry E. Characteristic processes of human evolution caused the Anthropocene and may obstruct its global solutions. Philos Trans R Soc Lond B Biol Sci 2024; 379:20220259. [PMID: 37952628 PMCID: PMC10645123 DOI: 10.1098/rstb.2022.0259] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2022] [Accepted: 06/19/2023] [Indexed: 11/14/2023] Open
Abstract
We propose that the global environmental crises of the Anthropocene are the outcome of a ratcheting process in long-term human evolution which has favoured groups of increased size and greater environmental exploitation. To explore this hypothesis, we review the changes in the human ecological niche. Evidence indicates the growth of the human niche has been facilitated by group-level cultural traits for environmental control. Following this logic, sustaining the biosphere under intense human use will probably require global cultural traits, including legal and technical systems. We investigate the conditions for the evolution of global cultural traits. We estimate that our species does not exhibit adequate population structure to evolve these traits. Our analysis suggests that characteristic patterns of human group-level cultural evolution created the Anthropocene and will work against global collective solutions to the environmental challenges it poses. We illustrate the implications of this theory with alternative evolutionary paths for humanity. We conclude that our species must alter longstanding patterns of cultural evolution to avoid environmental disaster and escalating between-group competition. We propose an applied research and policy programme with the goal of avoiding these outcomes. This article is part of the theme issue 'Evolution and sustainability: gathering the strands for an Anthropocene synthesis'.
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Affiliation(s)
- Timothy M. Waring
- Mitchell Center for Sustainability Solutions, University of Maine, Orono, ME 04469, USA
| | - Zachary T. Wood
- Department of Biology, Colby College, 4000 Mayflower Hill Drive, Waterville, ME 04901, USA
| | - Eörs Szathmáry
- Institute of Evolution, Centre for Ecological Research, Budapest, Hungary
- Center for the Conceptual Foundations of Science, Parmenides Foundation, Pöcking, Germany
- Plant Systematics, Ecology and Theoretical Biology, Eötvös University, Budapest, Hungary
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11
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Pisor AC, Borgerhoff Mulder M, Smith KM. Long-distance social relationships can both undercut and promote local natural resource management. Philos Trans R Soc Lond B Biol Sci 2024; 379:20220269. [PMID: 37952627 PMCID: PMC10645093 DOI: 10.1098/rstb.2022.0269] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2022] [Accepted: 07/05/2023] [Indexed: 11/14/2023] Open
Abstract
The management of large common-pool resources, like fisheries and forests, is more difficult when more people and more communities can access them-a particular problem given increased population sizes, higher mobility and globalized trade in the Anthropocene. Social relationships spanning communities, such as kin relationships, business or trade relationships and friendships, can make management even more challenging by facilitating and transmitting norms of overharvesting. However, these long-distance relationships can also bolster management by transmitting norms for sustainability, promoting interdependence and laying the groundwork for nested management systems. Here, we review the negative and positive impacts of long-distance relationships on local natural resource management (NRM), providing illustrative examples from our field research on forest and fisheries management in Tanzania. Drawing on the evolutionary literature, the development literature and our field data, we offer suggestions for how development partners can avoid the pitfalls of long-distance relationships and how they can use or even deliberately foster long-distance relationships to promote successful local NRM. This article is part of the theme issue 'Evolution and sustainability: gathering the strands for an Anthropocene synthesis'.
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Affiliation(s)
- Anne C. Pisor
- Department of Anthropology, Washington State University, Pullman, WA, USA
- Department of Human Behavior, Ecology, and Culture, Max Planck Institute for Evolutionary Anthropology, 04103, Leipzig, Germany
| | - Monique Borgerhoff Mulder
- Department of Human Behavior, Ecology, and Culture, Max Planck Institute for Evolutionary Anthropology, 04103, Leipzig, Germany
- Santa Fe Institute, New Mexico, 87506, NM, USA
- Department of Anthropology, University of California at Davis, Davis, 95616, CA, USA
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12
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van Leeuwen EJ, Staes N, Brooker JS, Kordon S, Nolte S, Clay Z, Eens M, Stevens JM. Group-specific expressions of co-feeding tolerance in bonobos and chimpanzees preclude dichotomous species generalizations. iScience 2023; 26:108528. [PMID: 38144453 PMCID: PMC10746535 DOI: 10.1016/j.isci.2023.108528] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2023] [Revised: 07/21/2023] [Accepted: 11/20/2023] [Indexed: 12/26/2023] Open
Abstract
Bonobos are typically portrayed as more socially tolerant than chimpanzees, yet the current evidence supporting such a species-level categorization is equivocal. Here, we used validated group-level co-feeding assays to systematically test expressions of social tolerance in sixteen groups of zoo- and sanctuary-housed bonobos and chimpanzees. We found that co-feeding tolerance substantially overlaps between the species, thus precluding categorical inference at the species level. Instead, marked differences were observed between groups, with some bonobo communities exhibiting higher social tolerance than chimpanzee communities, and vice versa. Moreover, considerable intergroup variation was found within species living in the same environment, which attests to Pan's behavioral flexibility. Lastly, chimpanzees showed more tolerance in male-skewed communities, whereas bonobos responded less pronounced to sex-ratio variation. We conclude that the pervasive dichotomy between the tolerant bonobo and the belligerent chimpanzee requires quantitative nuance, and that accurate phylogenetic tracing of (human) social behavior warrants estimations of intraspecific group variation.
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Affiliation(s)
- Edwin J.C. van Leeuwen
- Animal Behaviour and Cognition, Department of Biology, Utrecht University, Padualaan 8, Utrecht 3584 CA, the Netherlands
- Behavioural Ecology and Ecophysiology Group, Department of Biology, University of Antwerp, Universiteitsplein 1, 2610 Wilrijk, Belgium
- Centre for Research and Conservation, Royal Zoological Society of Antwerp, Koningin Astridplein 26, 2018 Antwerp, Belgium
- Department for Comparative Cultural Psychology, Max Planck Institute for Evolutionary Anthropology, Deutscher Platz 6, 04103 Leipzig, Germany
| | - Nicky Staes
- Behavioural Ecology and Ecophysiology Group, Department of Biology, University of Antwerp, Universiteitsplein 1, 2610 Wilrijk, Belgium
- Centre for Research and Conservation, Royal Zoological Society of Antwerp, Koningin Astridplein 26, 2018 Antwerp, Belgium
| | - Jake S. Brooker
- Psychology Department, Durham University, South Road, Durham DH1 3LE, UK
| | - Stephanie Kordon
- Psychology Department, Durham University, South Road, Durham DH1 3LE, UK
| | - Suska Nolte
- Animal Behaviour and Cognition, Department of Biology, Utrecht University, Padualaan 8, Utrecht 3584 CA, the Netherlands
| | - Zanna Clay
- Psychology Department, Durham University, South Road, Durham DH1 3LE, UK
| | - Marcel Eens
- Behavioural Ecology and Ecophysiology Group, Department of Biology, University of Antwerp, Universiteitsplein 1, 2610 Wilrijk, Belgium
| | - Jeroen M.G. Stevens
- Behavioural Ecology and Ecophysiology Group, Department of Biology, University of Antwerp, Universiteitsplein 1, 2610 Wilrijk, Belgium
- Centre for Research and Conservation, Royal Zoological Society of Antwerp, Koningin Astridplein 26, 2018 Antwerp, Belgium
- SALTO Agro- and Biotechnology, Odisee University College, Hospitaalstraat 23, 9100 Sint Niklaas, Belgium
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13
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Gautam H, Vidya TNC. Do food distribution and competitor density affect agonistic behaviour within and between clans in a high fission-fusion species? ROYAL SOCIETY OPEN SCIENCE 2023; 10:230990. [PMID: 38077213 PMCID: PMC10698478 DOI: 10.1098/rsos.230990] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 07/11/2023] [Accepted: 11/13/2023] [Indexed: 01/11/2024]
Abstract
According to the ecological model of female social relationships (EMFSR), within-group competition and between-group competition in female-bonded species are shaped by food distribution. Strong between-group contests are expected over large, monopolizable resources and high population density, but not when low-quality food is distributed across large, undefended home ranges. Within-group contests are expected to be more frequent with increasing heterogeneity among feeding sites and with group size. We tested these predictions in female Asian elephants, which show traits associated with infrequent contests-graminivory, high fission-fusion and overlapping home ranges. We examined how food distribution and competitor density affected agonistic interactions within and between female elephant clans (social groupings) in the Kabini grassland, southern India. We found stronger between-clan contest in the grassland than that known from neighbouring forests, and more frequent agonism between females between clans than within clans. Such strong between-clan contest was attributable to the grassland being a food-rich habitat patch, thus supporting the EMFSR. Within-clan agonism was also frequent, but did not increase with food heterogeneity, contradicting the EMFSR. Contrary to recent claims, increasing within-clan agonism with group size suggested ecological constraints on large groups despite high fission-fusion. High population density may explain such frequent contests despite graminivory and fission-fusion.
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Affiliation(s)
- Hansraj Gautam
- Evolutionary and Organismal Biology Unit, Jawaharlal Nehru Centre for Advanced Scientific Research (JNCASR), Bengaluru, India
| | - T. N. C. Vidya
- Evolutionary and Organismal Biology Unit, Jawaharlal Nehru Centre for Advanced Scientific Research (JNCASR), Bengaluru, India
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14
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Kramer KL, Hackman JV. Small-scale farmer responses to the double exposure of climate change and market integration. Philos Trans R Soc Lond B Biol Sci 2023; 378:20220396. [PMID: 37718597 PMCID: PMC10505847 DOI: 10.1098/rstb.2022.0396] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2023] [Accepted: 06/16/2023] [Indexed: 09/19/2023] Open
Abstract
Anthropologists have long studied how small-scale societies manage climate variation. Here, we investigate how Yucatec Maya subsistence farmers respond to climate stress, and the ways in which market integration may enhance or disturb response stategies. Using information on harvest returns, climate perceptions, household economics and helping networks, modelling results show that as farmers rely more on market inputs (e.g. seed, tractors, fertilizer) for a successful yield, the reasons given for a bad harvest shift from climate variables to access to quality inputs. We also find that social and economic diversification is key to mediating a household's experience of climate and market shocks. The Maya are astute stewards of climate knowledge, and have effective social and economic means to mitigate potential fluctuations in food availability. In the transition from a subsistence to a market integrated economy, these traditional strategies become strained. Reliance on market inputs forges a more rigid food production system that conflicts with the diversity and flexibility on which traditional strategies depend to manage climate variation. Moving forward, the best policies would be those that facilitate maintaining an equal footing in both a subsistence maize economy, while incorporating new market opportunities. This article is part of the theme issue 'Climate change adaptation needs a science of culture'.
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Affiliation(s)
- K. L. Kramer
- Department of Anthropology, University of Utah, Salt Lake City, UT 84112, USA
| | - J. V. Hackman
- Department of Anthropology, University of Utah, Salt Lake City, UT 84112, USA
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15
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Benítez-Burraco A, Hoshi K, Progovac L. The gradual coevolution of syntactic combinatorics and categorization under the effects of human self-domestication: a proposal. Cogn Process 2023; 24:425-439. [PMID: 37306792 PMCID: PMC10359229 DOI: 10.1007/s10339-023-01140-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2022] [Accepted: 04/15/2023] [Indexed: 06/13/2023]
Abstract
The gradual emergence of syntax has been claimed to be engaged in a feedback loop with Human Self-Domestication (HSD), both processes resulting from, and contributing to, enhanced connectivity in selected cortico-striatal networks, which is the mechanism for attenuating reactive aggression, the hallmark of HSD, but also the mechanism of cross-modality, relevant for syntax. Here, we aim to bridge the gap between these brain changes and further changes facilitated by the gradual complexification of grammars. We propose that increased cross-modality would have enabled and supported, more specifically, a feedback loop between categorization abilities relevant for vocabulary building and the gradual emergence of syntactic structure, including Merge. In brief, an enhanced categorization ability not only brings about more distinct categories, but also a critical number of tokens in each category necessary for Merge to take off in a systematic and productive fashion; in turn, the benefits of expressive capabilities brought about by productive Merge encourage more items to be categorized, and more categories to be formed, thus further potentiating categorization abilities, and with it, syntax again. We support our hypothesis with evidence from the domains of language development and animal communication, but also from biology, neuroscience, paleoanthropology, and clinical linguistics.
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Affiliation(s)
- Antonio Benítez-Burraco
- Department of Spanish, Linguistics and Theory of Literature (Linguistics), Faculty of Philology, University of Seville, Seville, Spain.
| | - Koji Hoshi
- Faculty of Economics, Keio University, Tokyo, Japan
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16
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Benítez-Burraco A, Nikolsky A. The (Co)Evolution of Language and Music Under Human Self-Domestication. HUMAN NATURE (HAWTHORNE, N.Y.) 2023; 34:229-275. [PMID: 37097428 PMCID: PMC10354115 DOI: 10.1007/s12110-023-09447-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Accepted: 03/27/2023] [Indexed: 04/26/2023]
Abstract
Together with language, music is perhaps the most distinctive behavioral trait of the human species. Different hypotheses have been proposed to explain why only humans perform music and how this ability might have evolved in our species. In this paper, we advance a new model of music evolution that builds on the self-domestication view of human evolution, according to which the human phenotype is, at least in part, the outcome of a process similar to domestication in other mammals, triggered by the reduction in reactive aggression responses to environmental changes. We specifically argue that self-domestication can account for some of the cognitive changes, and particularly for the behaviors conducive to the complexification of music through a cultural mechanism. We hypothesize four stages in the evolution of music under self-domestication forces: (1) collective protomusic; (2) private, timbre-oriented music; (3) small-group, pitch-oriented music; and (4) collective, tonally organized music. This line of development encompasses the worldwide diversity of music types and genres and parallels what has been hypothesized for languages. Overall, music diversity might have emerged in a gradual fashion under the effects of the enhanced cultural niche construction as shaped by the progressive decrease in reactive (i.e., impulsive, triggered by fear or anger) aggression and the increase in proactive (i.e., premeditated, goal-directed) aggression.
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Affiliation(s)
- Antonio Benítez-Burraco
- Department of Spanish Language, Linguistics and Literary Theory (Linguistics), Faculty of Philology, University of Seville, Seville, Spain.
- Departamento de Lengua Española, Facultad de Filología, Área de Lingüística General, Lingüística y Teoría de la Literatura, Universidad de Sevilla, C/ Palos de la Frontera s/n, Sevilla, 41007, España.
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17
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Kandza VH, Jang H, Ntamboudila FK, Lew-Levy S, Boyette AH. Intergroup Cooperation in Shotgun Hunting Among BaYaka Foragers and Yambe Farmers from the Republic of the Congo. HUMAN NATURE (HAWTHORNE, N.Y.) 2023:10.1007/s12110-023-09448-0. [PMID: 37099116 DOI: 10.1007/s12110-023-09448-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Accepted: 04/03/2023] [Indexed: 04/27/2023]
Abstract
Whereas many evolutionary models emphasize within-group cooperation or between-group competition in explaining human large-scale cooperation, recent work highlights a critical role for intergroup cooperation in human adaptation. Here we investigate intergroup cooperation in the domain of shotgun hunting in northern Republic of the Congo. In the Congo Basin broadly, forest foragers maintain relationships with neighboring farmers based on systems of exchange regulated by norms and institutions such as fictive kinship. In this study, we examine how relationships between Yambe farmers and BaYaka foragers support stable intergroup cooperation in the domain of shotgun hunting. In the study village, shotgun hunting is based on a specialization-based exchange wherein Yambe farmers contribute shotguns and access to markets to buy cartridges and sell meat while BaYaka foragers contribute their specialized forest knowledge and skill. To understand how costs and benefits are distributed, we conducted structured interviews with 77 BaYaka hunters and 15 Yambe gun owners and accompanied hunters on nine hunting trips. We found that hunts are organized in a conventional manner within a fictive kinship structure, consistent with the presence of intercultural mechanisms to stabilize cooperation. However, because bushmeat demand is high, gun owners can gain significant cash profit, while compensating hunters only with cigarettes, alcohol, and a traditional hunter's portion of meat. To level payoffs, hunters strategically hide kills or cartridges from gun owners to feed their own families. Our results illustrate how each group prioritizes different currencies (e.g., cash, meat, family, intergroup relations) and provide insights into how intergroup cooperation is stabilized in this setting. The example of this long-standing intergroup cooperative system is discussed in terms of its contemporary entwinement with logging, the bushmeat trade, and growing market intersection.
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Affiliation(s)
- Vidrige H Kandza
- Department of Human Behavior, Ecology and Culture, Max Planck Institute for Evolutionary Anthropology, Deutscher Platz 6, 04103, Leipzig, Germany.
| | - Haneul Jang
- Department of Human Behavior, Ecology and Culture, Max Planck Institute for Evolutionary Anthropology, Deutscher Platz 6, 04103, Leipzig, Germany
| | - Francy Kiabiya Ntamboudila
- Faculté des Lettres, Arts, et Sciences Humaines, Marien Ngouabi University, Brazzaville, Republic of the Congo
| | | | - Adam H Boyette
- Department of Human Behavior, Ecology and Culture, Max Planck Institute for Evolutionary Anthropology, Deutscher Platz 6, 04103, Leipzig, Germany
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18
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Rodrigues AMM, Barker JL, Robinson EJH. The evolution of intergroup cooperation. Philos Trans R Soc Lond B Biol Sci 2023; 378:20220074. [PMID: 36802776 PMCID: PMC9939261 DOI: 10.1098/rstb.2022.0074] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/21/2023] Open
Abstract
Sociality is widespread among animals, and involves complex relationships within and between social groups. While intragroup interactions are often cooperative, intergroup interactions typically involve conflict, or at best tolerance. Active cooperation between members of distinct, separate groups occurs very rarely, predominantly in some primate and ant species. Here, we ask why intergroup cooperation is so rare, and what conditions favour its evolution. We present a model incorporating intra- and intergroup relationships and local and long-distance dispersal. We show that dispersal modes play a pivotal role in the evolution of intergroup interactions. Both long-distance and local dispersal processes drive population social structure, and the costs and benefits of intergroup conflict, tolerance and cooperation. Overall, the evolution of multi-group interaction patterns, including both intergroup aggression and intergroup tolerance, or even altruism, is more likely with mostly localized dispersal. However, the evolution of these intergroup relationships may have significant ecological impacts, and this feedback may alter the ecological conditions that favour its own evolution. These results show that the evolution of intergroup cooperation is favoured by a specific set of conditions, and may not be evolutionarily stable. We discuss how our results relate to empirical evidence of intergroup cooperation in ants and primates. This article is part of a discussion meeting issue 'Collective behaviour through time'.
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Affiliation(s)
- António M. M. Rodrigues
- School of Biology, University of St Andrews, St Andrews, KY16 9TH, UK,Schools of Medicine and Engineering, Stanford University, Stanford, CA 94305, USA,Department of Ecology and Evolutionary Biology, Yale University, New Haven, CT 06511, USA
| | - Jessica L. Barker
- Surgo Ventures, Washington, DC 20036, USA,Interacting Minds Centre, Aarhus University, 8000 Aarhus, Denmark,Division of Population Health Sciences, University of Alaska Anchorage, Anchorage, AK 99508, USA
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19
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Fox SA, Scelza B, Silk J, Kramer KL. New perspectives on the evolution of women's cooperation. Philos Trans R Soc Lond B Biol Sci 2023; 378:20210424. [PMID: 36440567 PMCID: PMC9703265 DOI: 10.1098/rstb.2021.0424] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2022] [Accepted: 09/28/2022] [Indexed: 11/29/2022] Open
Abstract
A holistic, evolutionary framework about human cooperation must incorporate information about women's cooperative behaviour. Yet, most empirical research on human cooperation has centered on men's behaviour or been derived from experimental studies conducted in western, industrialized populations. These bodies of data are unlikely to accurately represent human behavioural diversity. To address this gap and provide a more balanced view of human cooperation, this issue presents substantial new data and multi-disciplinary perspectives to document the complexity of women's cooperative behaviour. Research in this issue 1) challenges narratives about universal gender differences in cooperation, 2) reconsiders patrilocality and access to kin as constraints on women's cooperation, 3) reviews evidence for a connection between social support and women's health and 4) examines the phylogenetic roots of female cooperation. Here, we discuss the steps taken in this issue toward a more complete and evidence-based understanding of the role that cooperation plays in women's and girls' lives and in building human sociality. This article is part of the theme issue 'Cooperation among women: evolutionary and cross-cultural perspectives'.
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Affiliation(s)
- Stephanie A. Fox
- Department of Anthropology, University of New Mexico, Albuquerque, NM 87131, USA
| | - Brooke Scelza
- Department of Anthropology, UCLA, Los Angeles, CA 90095, USA
| | - Joan Silk
- School of Human Evolution and Social Change, Arizona State University, Tempe, AZ 85281, USA
| | - Karen L. Kramer
- Department of Anthropology, University of Utah, Salt Lake City, UT 84112, USA
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20
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Hepach R, Engelmann JM, Herrmann E, Gerdemann SC, Tomasello M. Evidence for a developmental shift in the motivation underlying helping in early childhood. Dev Sci 2023; 26:e13253. [PMID: 35191158 PMCID: PMC10078187 DOI: 10.1111/desc.13253] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2021] [Revised: 01/27/2022] [Accepted: 02/08/2022] [Indexed: 12/15/2022]
Abstract
We investigated children's positive emotions as an indicator of their underlying prosocial motivation. In Study 1, 2-, and 5-year-old children (N = 64) could either help an individual or watch as another person provided help. Following the helping event and using depth sensor imaging, we measured children's positive emotions through changes in postural elevation. For 2-year-olds, helping the individual and watching another person help was equally rewarding; 5-year-olds showed greater postural elevation after actively helping. In Study 2, 5-year-olds' (N = 59) positive emotions following helping were greater when an audience was watching. Together, these results suggest that 2-year-old children have an intrinsic concern that individuals be helped whereas 5-year-old children have an additional, strategic motivation to improve their reputation by helping.
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Affiliation(s)
- Robert Hepach
- Department of Experimental Psychology, University of Oxford, Oxford, UK
| | - Jan M Engelmann
- Department of Psychology, University of California, Berkeley, California, USA
| | - Esther Herrmann
- Department of Psychology, University of Portsmouth, Portsmouth, UK
| | - Stella C Gerdemann
- Department of Research Methods in Early Child Development, Leipzig University, Leipzig, Germany.,Leipzig Research Center for Early Child Development, Leipzig University, Leipzig, Germany
| | - Michael Tomasello
- Department of Psychology and Neuroscience, Duke University, Durham, North Carolina, USA.,Department of Developmental and Comparative Psychology, Max Planck Institute of Evolutionary Anthropology, Leipzig, Germany
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21
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McGuire KM, Sauther ML. Characterizing group and individual engagement in intergroup encounters between small groups of ring-tailed lemurs (Lemur catta) on St. Catherines Island, USA. Primates 2023; 64:161-176. [PMID: 36418748 DOI: 10.1007/s10329-022-01036-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2022] [Accepted: 11/02/2022] [Indexed: 11/25/2022]
Abstract
Primate species exhibit considerable variation in behavior and outcomes during intergroup encounters (IGEs). Social group characteristics, like group size, and individual traits, such as sex, rank, and reproductive status, within those groups can influence both IGE engagement and outcomes. To better understand the impact of group heterogeneity on IGEs, we must examine individual strategies to elucidate individual costs and benefits of engaging in these interactions. Here, we present a descriptive study of the IGEs between two small social groups of ring-tailed lemurs (Lemur catta) on St. Catherines Island, GA, USA. We distinguish between dyadic and multiple-individual interactions between groups to compare collective and individual agonistic engagement. All encounters occurred when the East Road group (N = 7 individuals) traveled from the center of their home range to the boundary with Windmill group's (N = 5 individuals) home range, indicating that East Road might have been actively testing this boundary for access to food resources, sleeping trees, and mating opportunities. We also found notable individual variation in participation during IGEs. The daughters of the highest-ranking females were the most-engaged in dyadic intergroup and intragroup aggression, had high "win" rates during intergroup dyadic encounters, and engaged in intergroup multiple-individual interactions at high levels. These findings indicate that they might value their home range more as "potential alphas" compared to other group members. Dominant females were the most engaged in multiple-individual interactions, suggesting that they contribute heavily to collective action that might result in a gain or loss of access to resources. Finally, these two small groups might be equally matched despite the two-individual group size disparity due to individual free-riding strategies. Future research should focus on individual strategies during IGEs to characterize the complex decisions and trade-offs that influence participation.
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Affiliation(s)
- Kathleen M McGuire
- Department of Anthropology, University of Colorado Boulder, Boulder, CO, 80302, USA.
| | - Michelle L Sauther
- Department of Anthropology, University of Colorado Boulder, Boulder, CO, 80302, USA
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22
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Glowacki L. The evolution of peace. Behav Brain Sci 2022; 47:e1. [PMID: 36524358 DOI: 10.1017/s0140525x22002862] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
While some species have affiliative and even cooperative interactions between individuals of different social groups, humans are alone in having durable, positive-sum, interdependent relationships across unrelated social groups. Our capacity to have harmonious relationships that cross group boundaries is an important aspect of our species' success, allowing for the exchange of ideas, materials, and ultimately enabling cumulative cultural evolution. Knowledge about the conditions required for peaceful intergroup relationships is critical for understanding the success of our species and building a more peaceful world. How do humans create harmonious relationships across group boundaries and when did this capacity emerge in the human lineage? Answering these questions involves considering the costs and benefits of intergroup cooperation and aggression, for oneself, one's group, and one's neighbor. Taking a game theoretical perspective provides new insights into the difficulties of removing the threat of war and reveals an ironic logic to peace - the factors that enable peace also facilitate the increased scale and destructiveness of conflict. In what follows, I explore the conditions required for peace, why they are so difficult to achieve, and when we expect peace to have emerged in the human lineage. I argue that intergroup cooperation was an important component of human relationships and a selective force in our species history beginning at least 300 thousand years. But the preconditions for peace only emerged in the past 100 thousand years and likely coexisted with intermittent intergroup violence which would have also been an important and selective force in our species' history.
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Affiliation(s)
- Luke Glowacki
- Department of Anthropology, Boston University, Boston, MA, USA ://www.hsb-lab.org/
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23
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Pope-Caldwell S, Lew-Levy S, Maurits L, Boyette AH, Ellis-Davies K, Haun D, Over H, House BR. The social learning and development of intra- and inter-ethnic sharing norms in the Congo Basin: A registered report protocol. PLoS One 2022; 17:e0276845. [PMCID: PMC9665382 DOI: 10.1371/journal.pone.0276845] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2022] [Accepted: 10/12/2022] [Indexed: 11/17/2022] Open
Abstract
Compared to other species, the extent of human cooperation is unparalleled. Such cooperation is coordinated between community members via social norms. Developmental research has demonstrated that very young children are sensitive to social norms, and that social norms are internalized by middle childhood. Most research on social norm acquisition has focused on norms that modulated intra-group cooperation. Yet around the world, multi-ethnic communities also cooperate, and this cooperation is often shaped by distinct inter-group social norms. In the present study, we will investigate whether inter-ethnic and intra-ethnic social norm acquisition follows the same, or distinct, developmental trajectories. Specifically, we will work with BaYaka foragers and Bandongo fisher-farmers who inhabit multi-ethnic villages in the Republic of the Congo. In these villages, inter-ethnic cooperation is regulated by sharing norms. Through interviews with adult participants, we will provide the first descriptive account of the timing and mechanism by which BaYaka and Bandongo learn to share with out-group members. Children (5–17 years) and adults (17+ years) will also participate in a modified Dictator Game to investigate the developmental trajectories of children’s intra- and inter-ethnic sharing choices. Based on our ethnographic knowledge of the participating communities, we predict that children’s intra-ethnic sharing choices in the Dictator Game will match those of adults at an earlier age than their inter-ethnic sharing choices. We will analyze our data using logistic Bayesian modelling.
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Affiliation(s)
- Sarah Pope-Caldwell
- Department of Comparative Cultural Psychology, Max Planck Institute for Evolutionary Anthropology, Leipzig, Germany
- * E-mail: (SPC); (SLL)
| | - Sheina Lew-Levy
- Department of Psychology, Durham University, Durham, United Kingdom
- Department of Human Behavior, Ecology, and Culture, Max Planck Institute for Evolutionary Anthropology, Leipzig, Germany
- * E-mail: (SPC); (SLL)
| | - Luke Maurits
- Department of Comparative Cultural Psychology, Max Planck Institute for Evolutionary Anthropology, Leipzig, Germany
| | - Adam H. Boyette
- Department of Human Behavior, Ecology, and Culture, Max Planck Institute for Evolutionary Anthropology, Leipzig, Germany
| | - Kate Ellis-Davies
- Department of Psychology, Swansea University, Swansea, United Kingdom
| | - Daniel Haun
- Department of Comparative Cultural Psychology, Max Planck Institute for Evolutionary Anthropology, Leipzig, Germany
- Leipzig Research Centre for Early Child Development, Leipzig University, Leipzig, Germany
| | - Harriet Over
- Department of Psychology, University of York, York, United Kingdom
| | - Bailey R. House
- Department of Psychology, University of York, York, United Kingdom
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24
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Rucas SL, Alami S. Female-Female Competition Occurs Irrespective of Patrilocality. ARCHIVES OF SEXUAL BEHAVIOR 2022; 51:3287-3292. [PMID: 34799834 DOI: 10.1007/s10508-021-02221-3] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/23/2021] [Revised: 11/05/2021] [Accepted: 11/06/2021] [Indexed: 06/13/2023]
Affiliation(s)
- Stacey L Rucas
- Department of Social Sciences, California Polytechnic State University, 1 Grand Avenue, San Luis Obispo, CA, 93407-0329, USA.
| | - Sarah Alami
- Department of Anthropology, University of California, Santa Barbara, CA, USA
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25
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Smith KM, Pisor AC, Aron B, Bernard K, Fimbo P, Kimesera R, Borgerhoff Mulder M. Friends near and afar, through thick and thin: Comparing contingency of help between close-distance and long-distance friends in Tanzanian fishing villages. EVOL HUM BEHAV 2022. [DOI: 10.1016/j.evolhumbehav.2022.09.004] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
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27
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Braga Goncalves I, Morris-Drake A, Kennedy P, Radford AN. Fitness consequences of outgroup conflict. eLife 2022; 11:e74550. [PMID: 35833830 PMCID: PMC9282852 DOI: 10.7554/elife.74550] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2021] [Accepted: 06/27/2022] [Indexed: 12/13/2022] Open
Abstract
In social species across the animal kingdom, conspecific outsiders threaten the valuable resources of groups and their members. This outgroup conflict is recognised as a powerful selection pressure, but we argue that studies explicitly quantifying the fitness consequences need to be broader in scope: more attention should be paid to delayed, cumulative, and third-party fitness consequences, not just those arising immediately to group members involved in physical contests. In the first part of this review, we begin by documenting how single contests can have survival and reproductive consequences either immediately or with a delay. Then, we step beyond contests to describe fitness consequences that can also result from interactions with cues of rival presence and the general landscape of outgroup threat, and beyond single interactions to describe cumulative effects of territorial pressure and elevated outgroup-induced stress. Using examples from a range of taxa, we discuss which individuals are affected negatively and positively, considering both interaction participants and third-party group members of the same or the next generation. In the second part of the review, we provide suggestions about how to move forward. We highlight the importance of considering how different types of outgroup conflict can generate different selection pressures and of investigating variation in fitness consequences within and between species. We finish by discussing the value of theoretical modelling and long-term studies of natural populations, experimental manipulations, and meta-analyses to develop further our understanding of this crucial aspect of sociality.
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Affiliation(s)
| | - Amy Morris-Drake
- School of Biological Sciences, University of BristolBristolUnited Kingdom
| | - Patrick Kennedy
- School of Biological Sciences, University of BristolBristolUnited Kingdom
| | - Andrew N Radford
- School of Biological Sciences, University of BristolBristolUnited Kingdom
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28
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Brooks J, Kano F, Kawaguchi Y, Yamamoto S. Oxytocin promotes species-relevant outgroup attention in bonobos and chimpanzees. Horm Behav 2022; 143:105182. [PMID: 35537292 DOI: 10.1016/j.yhbeh.2022.105182] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/16/2021] [Revised: 04/20/2022] [Accepted: 04/22/2022] [Indexed: 11/30/2022]
Abstract
Previous research has found that oxytocin (OT) is associated with intergroup behaviour in humans as well as wild chimpanzees, and that exogenous OT affects Pan social attention. The two Pan species, bonobos and chimpanzees, differ drastically from one another in their intensity of intergroup competition, with lethal intergroup aggression often led by males in chimpanzees and more tolerant associations often centered around females in bonobos. However, it remains unclear how exogenous OT changes the two species' responses to ingroup and outgroup individuals. In this study, after intranasal administration of nebulized OT or placebo control, chimpanzees and bonobos viewed image pairs of ingroup and outgroup conspecifics while their eye movements were tracked with an eye-tracker. Although the overall effect of OT was small, we found that OT shifted bonobos' and chimpanzees' attention to outgroup images of the sex primarily involved in intergroup encounters in each species. Specifically, OT selectively shifted attention towards outgroup photos of female conspecifics in bonobos, and those of outgroup male conspecifics in chimpanzees. This suggests that OT generally promotes outgroup attention in both bonobos and chimpanzees but this effect is restricted to the sex most relevant in intergroup relations. These results suggest that, although OT may have a generally conserved role in hominid intergroup behaviour, it may act in species-relevant ways under the influence of their socio-ecological backgrounds.
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Affiliation(s)
- James Brooks
- Wildlife Research Center, Kyoto University, 6068203 Kyoto, Japan; Kumamoto Sanctuary, Kyoto University, 8693201 Kumamoto, Japan.
| | - Fumihiro Kano
- Kumamoto Sanctuary, Kyoto University, 8693201 Kumamoto, Japan; Center for the Advanced Study of Collective Behaviour, University of Konstanz, 78464 Konstanz, Germany; Max-Planck Institute of Animal Behavior, 78315 Radolfzell, Germany.
| | - Yuri Kawaguchi
- Messerli Research Institute, University of Veterinary Medicine Vienna, A-1210 Vienna, Austria; Japan Society for the Promotion of Science (JSPS), 1020083 Tokyo, Japan; Primate Research Institute, Kyoto University, 4848506 Inuyama, Japan
| | - Shinya Yamamoto
- Wildlife Research Center, Kyoto University, 6068203 Kyoto, Japan; Insitute for Advanced Study, Kyoto University, 6068501 Kyoto, Japan
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Characterization of Pan social systems reveals in-group/out-group distinction and out-group tolerance in bonobos. Proc Natl Acad Sci U S A 2022; 119:e2201122119. [PMID: 35727986 DOI: 10.1073/pnas.2201122119] [Citation(s) in RCA: 13] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Human between-group interactions are highly variable, ranging from violent to tolerant and affiliative. Tolerance between groups is linked to our unique capacity for large-scale cooperation and cumulative culture, but its evolutionary origins are understudied. In chimpanzees, one of our closest living relatives, predominantly hostile between-group interactions impede cooperation and information flow across groups. In contrast, in our other closest living relative, the bonobo, tolerant between-group associations are observed. However, as these associations can be frequent and prolonged and involve social interactions that mirror those within groups, it is unclear whether these bonobos really do belong to separate groups. Alternatively, the bonobo grouping patterns may be homologous to observations from the large Ngogo chimpanzee community, where individuals form within-group neighborhoods despite sharing the same membership in the larger group. To characterize bonobo grouping patterns, we compare the social structure of the Kokolopori bonobos with the chimpanzee group of Ngogo. Using cluster analysis, we find temporally stable clusters only in bonobos. Despite the large spatial overlap and frequent interactions between the bonobo clusters, we identified significant association preference within but not between clusters and a unique space use of each cluster. Although bonobo associations are flexible (i.e., fission-fusion dynamics), cluster membership predicted the bonobo fission compositions and the spatial cohesion of individuals during encounters. These findings suggest the presence of a social system that combines clear in-group/out-group distinction and out-group tolerance in bonobos, offering a unique referential model for the evolution of tolerant between-group interactions in humans.
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De Dreu CKW, Triki Z. Intergroup conflict: origins, dynamics and consequences across taxa. Philos Trans R Soc Lond B Biol Sci 2022; 377:20210134. [PMID: 35369751 PMCID: PMC8977662 DOI: 10.1098/rstb.2021.0134] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022] Open
Abstract
Although uniquely destructive and wasteful, intergroup conflict and warfare are not confined to humans. They are seen across a range of group-living species, from social insects, fishes and birds to mammals, including nonhuman primates. With its unique collection of theory, research and review contributions from biology, anthropology and economics, this theme issue provides novel insights into intergroup conflict across taxa. Here, we introduce and organize this theme issue on the origins and consequences of intergroup conflict. We provide a coherent framework by modelling intergroup conflicts as multi-level games of strategy in which individuals within groups cooperate to compete with (individuals in) other groups for scarce resources, such as territory, food, mating opportunities, power and influence. Within this framework, we identify cross-species mechanisms and consequences of (participating in) intergroup conflict. We conclude by highlighting crosscutting innovations in the study of intergroup conflict set forth by individual contributions. These include, among others, insights on how within-group heterogeneities and leadership relate to group conflict, how intergroup conflict shapes social organization and how climate change and environmental degradation transition intergroup relations from peaceful coexistence to violent conflict. This article is part of the theme issue ‘Intergroup conflict across taxa’.
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Affiliation(s)
- Carsten K W De Dreu
- Institute of Psychology, Leiden University, Leiden, The Netherlands.,Center for Research in Experimental Economics and Political Decision Making, University of Amsterdam, Amsterdam, The Netherlands
| | - Zegni Triki
- Department of Zoology, Stockholm University, Stockholm, Sweden
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García MG, de Guinea M, Bshary R, van de Waal E. Drivers and outcomes of between-group conflict in vervet monkeys. Philos Trans R Soc Lond B Biol Sci 2022; 377:20210145. [PMID: 35369750 PMCID: PMC8977665 DOI: 10.1098/rstb.2021.0145] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022] Open
Abstract
Neighbouring groups compete over access to resources and territories in between-group encounters, which can escalate into between-group conflicts (BGCs). Both the ecological characteristics of a territory and the rival's fighting ability shape the occurrence and outcome of such contests. What remains poorly understood, however, is how seasonal variability in the ecological value of a territory together with fighting ability related to the likelihood of between-group encounters and the extent to which these escalate into conflicts. To test this, we observed and followed four vervet monkey groups in the wild, and recorded the group structure (i.e. size, composition), the locations and the outcomes of 515 BGCs. We then assessed key ecological measures at these locations, such as vegetation availability (estimated from Copernicus Sentinel 2 satellite images) and the intensity of usage of these locations. We tested to what extent these factors together influenced the occurrence and outcomes of BGCs. We found that the occurrence of BGCs increased at locations with higher vegetation availability relative to the annual vegetation availability within the group's home territory. Also, groups engaging in a BGC at locations far away from their home territory were less likely to win a BGC. Regarding group structure, we found that smaller groups systematically won BGCs against larger groups, which can be explained by potentially higher rates of individual free-riding occurring in larger groups. This study sheds light on how the ecology of encounter locations in combination with a group's social characteristics can critically impact the dynamics of BGCs in a non-human primate species. This article is part of the theme issue ‘Intergroup conflict across taxa’.
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Affiliation(s)
- Miguel Gareta García
- Inkawu Vervet Project, Mawana Game Reserve, KwaZulu Natal 3115, South Africa.,Department of Eco-Ethology, Faculty of Biology, University of Neuchâtel, Rue Emile Argand 11, Neuchâtel 2000, Switzerland
| | - Miguel de Guinea
- Movement Ecology Laboratory, Alexander Silverman Institute of Life Sciences, Department of Ecology, Evolution and Behavior, The Hebrew University of Jerusalem, Jerusalem 91904, Israel
| | - Redouan Bshary
- Inkawu Vervet Project, Mawana Game Reserve, KwaZulu Natal 3115, South Africa.,Department of Eco-Ethology, Faculty of Biology, University of Neuchâtel, Rue Emile Argand 11, Neuchâtel 2000, Switzerland
| | - Erica van de Waal
- Inkawu Vervet Project, Mawana Game Reserve, KwaZulu Natal 3115, South Africa.,Department of Ecology and Evolution, Faculty of Biology and Medicine, University of Lausanne, Lausanne 1015, Switzerland
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Moscovice LR, Hohmann G, Trumble BC, Fruth B, Jaeggi AV. Dominance or Tolerance? Causes and consequences of a period of increased intercommunity encounters among bonobos (Pan paniscus) at LuiKotale. INT J PRIMATOL 2022. [DOI: 10.1007/s10764-022-00286-y] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
AbstractGroup-living primates exhibit variable reactions to intergroup encounters (or IGEs), reflecting species-specific strategies and individual motivations. In chimpanzees (Pan troglodytes), dominating in IGEs provides fitness benefits. Less is known about responses to IGEs in bonobos (Pan paniscus) despite their equal relevance for understanding the origins of human intergroup relations. We observed the Bompusa West (WBp) bonobo community at LuiKotale during a 2-month shift in ranging resulting in frequent IGEs with the smaller Bompusa East (EBp) community. We tested whether incursions provided ecological benefits, and whether responses to IGEs were consistent with inter-community dominance or tolerance. We measured fruit availability and collected activity scans from 26 mature WBp community members when in their core ranging area, during incursions into the EBp ranging area, and during IGEs. We collected data on sexual interactions and aggression with in-group and out-group members during 19 independent IGEs. During their shift in ranging, fruit availability was greater in the EBp ranging area, and WBp bonobos consumed more fruit during incursions than when in their core ranging area. Coalitionary intergroup aggression occurred during nine IGEs, and outcomes were consistent with imbalances in fighting power, in that larger WBp parties supplanted smaller EBp parties from the immediate area. However, communities reformed associations following 70% of coalitionary conflicts, and prolonged IGEs facilitated out-group sexual interactions and female transfers. The WBp community shift in ranging was likely motivated by ecological factors and responses to increased IGEs reflected a mixture of competitive and tolerant strategies.
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Boyette AH, Lew-Levy S, Jang H, Kandza V. Social ties in the Congo Basin: insights into tropical forest adaptation from BaYaka and their neighbours. Philos Trans R Soc Lond B Biol Sci 2022; 377:20200490. [PMID: 35249385 PMCID: PMC8899623 DOI: 10.1098/rstb.2020.0490] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2021] [Accepted: 01/05/2022] [Indexed: 12/18/2022] Open
Abstract
Investigating past and present human adaptation to the Congo Basin tropical forest can shed light on how climate and ecosystem variability have shaped human evolution. Here, we first review and synthesize genetic, palaeoclimatological, linguistic and historical data on the peopling of the Congo Basin. While forest fragmentation led to the increased genetic and geographical divergence of forest foragers, these groups maintained long-distance connectivity. The eventual expansion of Bantu speakers into the Congo Basin provided new opportunities for forging inter-group links, as evidenced by linguistic shifts and historical accounts. Building from our ethnographic work in the northern Republic of the Congo, we show how these inter-group links between forest forager communities as well as trade relationships with neighbouring farmers facilitate adaptation to ecoregions through knowledge exchange. While researchers tend to emphasize forager-farmer interactions that began in the Iron Age, we argue that foragers' cultivation of relational wealth with groups across the region played a major role in the initial occupation of the Congo Basin and, consequently, in cultural evolution among the ancestors of contemporary peoples. This article is part of the theme issue 'Tropical forests in the deep human past'.
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Affiliation(s)
- Adam H. Boyette
- Department of Human Behavior, Ecology and Culture, Max Planck Institute for Evolutionary Anthropology, Deutscher Platz 6, 04103 Leipzig, Germany
| | - Sheina Lew-Levy
- Department of Human Behavior, Ecology and Culture, Max Planck Institute for Evolutionary Anthropology, Deutscher Platz 6, 04103 Leipzig, Germany
- Department of Comparative Cultural Psychology, Max Planck Institute for Evolutionary Anthropology, Deutscher Platz 6, 04103 Leipzig, Germany
| | - Haneul Jang
- Department of Human Behavior, Ecology and Culture, Max Planck Institute for Evolutionary Anthropology, Deutscher Platz 6, 04103 Leipzig, Germany
| | - Vidrige Kandza
- Department of Human Behavior, Ecology and Culture, Max Planck Institute for Evolutionary Anthropology, Deutscher Platz 6, 04103 Leipzig, Germany
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Love thy neighbour: behavioural and endocrine correlates of male strategies during intergroup encounters in bonobos. Anim Behav 2022. [DOI: 10.1016/j.anbehav.2022.02.014] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
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Pisor AC, Ross CT. Distinguishing Intergroup and Long-Distance Relationships. HUMAN NATURE (HAWTHORNE, N.Y.) 2022; 33:280-303. [PMID: 36181615 PMCID: PMC9741575 DOI: 10.1007/s12110-022-09431-1] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Accepted: 09/07/2022] [Indexed: 11/05/2022]
Abstract
Intergroup and long-distance relationships are both central features of human social life, but because intergroup relationships are emphasized in the literature, long-distance relationships are often overlooked. Here, we make the case that intergroup and long-distance relationships should be studied as distinct, albeit related, features of human sociality. First, we review the functions of both kinds of relationship: while both can be conduits for difficult-to-access resources, intergroup relationships can reduce intergroup conflict whereas long-distance relationships are especially effective at buffering widespread resource shortfalls. Second, to illustrate the importance of distinguishing the two relationship types, we present a case study from rural Bolivia. Combining ethnography and two different experimental techniques, we find that the importance of intergroup relationships-and the salience of group membership itself-varies across populations and across methods. Although ethnography revealed that participants often rely on long-distance relationships for resource access, we were unable to capture participant preferences for these relationships with a forced-choice technique. Taken together, our review and empirical data highlight that (1) intergroup and long-distance relationships can have different functions and can be more or less important in different contexts and (2) validating experimental field data with ethnography is crucial for work on human sociality. We close by outlining future directions for research on long-distance relationships in humans.
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Affiliation(s)
- Anne C. Pisor
- grid.30064.310000 0001 2157 6568Department of Anthropology, Washington State University, Pullman, WA USA ,grid.419518.00000 0001 2159 1813Department of Human Behavior, Ecology and Culture, Max Planck Institute for Evolutionary Anthropology, Leipzig, Germany
| | - Cody T. Ross
- grid.419518.00000 0001 2159 1813Department of Human Behavior, Ecology and Culture, Max Planck Institute for Evolutionary Anthropology, Leipzig, Germany
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Samuni L, Lemieux D, Lamb A, Galdino D, Surbeck M. Tool use behavior in three wild bonobo communities at Kokolopori. Am J Primatol 2021; 84:e23342. [PMID: 34694658 DOI: 10.1002/ajp.23342] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2021] [Revised: 10/08/2021] [Accepted: 10/15/2021] [Indexed: 12/31/2022]
Abstract
Comparative studies on tool technologies in extant primates, especially in our closest living relatives, offer a window into the evolutionary foundations of tool use in hominins. Whereas chimpanzee tool technology is well studied across populations, the scarcity of described tool technology in wild populations of our other closest living relative, the bonobo, is a mystery. Here we provide a first report of the tool use repertoire of the Kokolopori bonobos and describe in detail the use of leaf-umbrellas during rainfall, with the aim to improve our knowledge of bonobo tool use capacity in the wild. The tool use repertoire of the Kokolopori bonobos was most similar to that of the nearby population of Wamba and comprised eight behaviors, none in a foraging context. Further, over a 6-month period we documented 44 instances of leaf-umbrella use by 22 individuals from three communities, suggesting that this behavior is habitual. Most leaf-umbrella tool users were adult females, and we observed a nonadult using a leaf-umbrella on only a single occasion. While the study and theory of tool technologies is often based on the use of tools in foraging tasks, tool use in bonobos typically occurs in nonforaging contexts across populations. Therefore, incorporating both foraging and nonforaging contexts into our theoretical framework is essential if we wish to advance our understanding of the evolutionary trajectories of tool technology in humans.
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Affiliation(s)
- Liran Samuni
- Department of Human Evolutionary Biology, Harvard University, Cambridge, Massachusetts, USA.,Kokolopori Bonobo Research Project, Tshuapa, Democratic Republic of the Congo.,Department of Primatology, Max Planck Institute of Evolutionary Anthropology, Leipzig, Germany
| | - David Lemieux
- Kokolopori Bonobo Research Project, Tshuapa, Democratic Republic of the Congo
| | - Alicia Lamb
- Kokolopori Bonobo Research Project, Tshuapa, Democratic Republic of the Congo.,Department of Biology, Clarkson University, Potsdam, New York, USA
| | - Daiane Galdino
- Kokolopori Bonobo Research Project, Tshuapa, Democratic Republic of the Congo
| | - Martin Surbeck
- Department of Human Evolutionary Biology, Harvard University, Cambridge, Massachusetts, USA.,Kokolopori Bonobo Research Project, Tshuapa, Democratic Republic of the Congo.,Department of Primatology, Max Planck Institute of Evolutionary Anthropology, Leipzig, Germany
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Evolutionary linguistics can help refine (and test) hypotheses about how music might have evolved. Behav Brain Sci 2021; 44:e64. [PMID: 34588005 DOI: 10.1017/s0140525x20000680] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
Both the music and social bonding (MSB) hypothesis and the music as a credible signal hypothesis emerge as solid views of how human music and human musicality might have evolved. Nonetheless, both views could be improved (and tested in better ways) with the consideration of the way in which human language(s) might have evolved under the effects of our self-domestication.
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Benítez-Burraco A, Pörtl D, Jung C. Did Dog Domestication Contribute to Language Evolution? Front Psychol 2021; 12:695116. [PMID: 34589022 PMCID: PMC8473740 DOI: 10.3389/fpsyg.2021.695116] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2021] [Accepted: 08/02/2021] [Indexed: 11/20/2022] Open
Abstract
Different factors seemingly account for the emergence of present-day languages in our species. Human self-domestication has been recently invoked as one important force favoring language complexity mostly via a cultural mechanism. Because our self-domestication ultimately resulted from selection for less aggressive behavior and increased prosocial behavior, any evolutionary or cultural change impacting on aggression levels is expected to have fostered this process. Here, we hypothesize about a parallel domestication of humans and dogs, and more specifically, about a positive effect of our interaction with dogs on human self-domestication, and ultimately, on aspects of language evolution, through the mechanisms involved in the control of aggression. We review evidence of diverse sort (ethological mostly, but also archeological, genetic, and physiological) supporting such an effect and propose some ways of testing our hypothesis.
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Affiliation(s)
- Antonio Benítez-Burraco
- Department of Spanish, Linguistics, and Theory of Literature (Linguistics), Faculty of Philology, University of Seville, Seville, Spain
| | - Daniela Pörtl
- Psychiatric Department, Saale-Unstrut Klinikum, Teaching Hospital Leipzig and Jena Universities, Naumburg, Germany
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Segovia-Cuéllar A, Del Savio L. On the use of evolutionary mismatch theories in debating human prosociality. MEDICINE, HEALTH CARE, AND PHILOSOPHY 2021; 24:305-314. [PMID: 33982191 PMCID: PMC8349330 DOI: 10.1007/s11019-021-10025-4] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Accepted: 05/08/2021] [Indexed: 06/12/2023]
Abstract
According to some evolutionary theorists human prosocial dispositions emerged in a context of inter-group competition and violence that made our psychology parochially prosocial, ie. cooperative towards in-groups and competitive towards strangers. This evolutionary hypothesis is sometimes employed in bioethical debates to argue that human nature and contemporary environments, and especially large-scale societies, are mismatched. In this article we caution against the use of mismatch theories in moral philosophy in general and discuss empirical evidence that puts into question mismatch theories based on parochial prosociality. Evolutionary mismatch theories play at best a rhetorical role in these moral debates and may misrepresent the status of relevant evolutionary research. We finally recommend that moral philosophers interested in the evolutionary literature also engage with dispositions such as xenophilia and social tolerance to counterbalance the focus on psychological mismatches adopted so far.
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DeTroy SE, Haun DBM, van Leeuwen EJC. What isn't social tolerance? The past, present, and possible future of an overused term in the field of primatology. Evol Anthropol 2021; 31:30-44. [PMID: 34460130 DOI: 10.1002/evan.21923] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2020] [Revised: 04/30/2021] [Accepted: 07/23/2021] [Indexed: 12/28/2022]
Abstract
In the past four decades, the term social tolerance has been utilized to describe, explain, and predict many different aspects of primates' sociality and has been measured with a large range of traits and behaviors. To date, however, there has been little discussion on whether these different phenomena all reflect one and the same construct. This paper opens the discussion by presenting the historical development of the term social tolerance and a structured overview of its current, overextended use. We argue that social tolerance has developed to describe two distinct concepts: social tolerance as the social structure of a group and social tolerance as the dyadic or group-level manifestation of tolerant behaviors. We highlight how these two concepts are based on conflicting theoretical understandings and practical assessments. In conclusion, we present suggestions for future research on primate social tolerance, which will allow for a more systematic and comparable investigation of primate sociality.
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Affiliation(s)
- Sarah E DeTroy
- Department for Comparative Cultural Psychology, Max Planck Institute for Evolutionary Anthropology, Leipzig, Germany.,Leipzig Research Centre for Early Child Development & Department for Early Child Development and Culture, Faculty of Education, Leipzig University, Leipzig, Germany
| | - Daniel B M Haun
- Department for Comparative Cultural Psychology, Max Planck Institute for Evolutionary Anthropology, Leipzig, Germany.,Leipzig Research Centre for Early Child Development & Department for Early Child Development and Culture, Faculty of Education, Leipzig University, Leipzig, Germany
| | - Edwin J C van Leeuwen
- Behavioral Ecology and Ecophysiology Group, Department of Biology, University of Antwerp, Antwerp, Belgium.,Centre for Research and Conservation, Royal Zoological Society of Antwerp, Antwerp, Belgium
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41
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Grueter CC, Wilson ML. Do we need to reclassify the social systems of gregarious apes? Evol Anthropol 2021; 30:316-326. [PMID: 34343382 DOI: 10.1002/evan.21919] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2020] [Revised: 11/19/2020] [Accepted: 07/01/2021] [Indexed: 11/07/2022]
Abstract
Decades of research have led to a solid understanding of the social systems of gregarious apes: chimpanzees, bonobos, gorillas, and gibbons. As field studies have increasingly collected data from multiple neighboring habituated groups, genetic and social interconnections have been revealed. These findings provide a more nuanced picture of intergroup relations in apes, and have led to claims in the literature that some ape taxa have multilevel societies. A multilevel society is defined as a nested collection of social entities comprising at least two discernible levels of social integration between the individual and the population. We argue that the evidence for multilevel sociality sensu stricto in apes is currently inconclusive and that it is premature to abandon the traditional classification of ape social systems. However, available findings appear to be consistent with the existence of some degree of higher social grouping patterns. We propose the term supra-group organization which may adequately capture ape social systems when viewed from a top-down perspective.
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Affiliation(s)
- Cyril C Grueter
- Department of Anatomy, Physiology and Human Biology, School of Human Sciences, The University of Western Australia, Perth, WA, Australia
- Centre for Evolutionary Biology, School of Biological Sciences, The University of Western Australia, Perth, WA, Australia
- International Centre of Biodiversity and Primate Conservation, Dali University, Dali, Yunnan, China
| | - Michael L Wilson
- Department of Anthropology, University of Minnesota, Minneapolis, Minnesota, USA
- Department of Ecology, Evolution and Behavior, University of Minnesota, Saint Paul, Minnesota, USA
- Institute on the Environment, University of Minnesota, St. Paul, Minnesota, USA
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Middle Pleistocene fire use: The first signal of widespread cultural diffusion in human evolution. Proc Natl Acad Sci U S A 2021; 118:2101108118. [PMID: 34301807 PMCID: PMC8346817 DOI: 10.1073/pnas.2101108118] [Citation(s) in RCA: 25] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Control of fire is one of the most important technological innovations within the evolution of humankind. The archaeological signal of fire use becomes very visible from around 400,000 y ago onward. Interestingly, this occurs at a geologically similar time over major parts of the Old World, in Africa, as well as in western Eurasia, and in different subpopulations of the wider hominin metapopulation. We interpret this spatiotemporal pattern as the result of cultural diffusion, and as representing the earliest clear-cut case of widespread cultural change resulting from diffusion in human evolution. This fire-use pattern is followed slightly later by a similar spatiotemporal distribution of Levallois technology, at the beginning of the African Middle Stone Age and the western Eurasian Middle Paleolithic. These archaeological data, as well as studies of ancient genomes, lead us to hypothesize that at the latest by 400,000 y ago, hominin subpopulations encountered one another often enough and were sufficiently tolerant toward one another to transmit ideas and techniques over large regions within relatively short time periods. Furthermore, it is likely that the large-scale social networks necessary to transmit complicated skills were also in place. Most importantly, this suggests a form of cultural behavior significantly more similar to that of extant Homo sapiens than to our great ape relatives.
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Benítez-Burraco A, Ferretti F, Progovac L. Human Self-Domestication and the Evolution of Pragmatics. Cogn Sci 2021; 45:e12987. [PMID: 34170029 DOI: 10.1111/cogs.12987] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2020] [Revised: 04/25/2021] [Accepted: 04/26/2021] [Indexed: 12/11/2022]
Abstract
As proposed for the emergence of modern languages, we argue that modern uses of languages (pragmatics) also evolved gradually in our species under the effects of human self-domestication, with three key aspects involved in a complex feedback loop: (a) a reduction in reactive aggression, (b) the sophistication of language structure (with emerging grammars initially facilitating the transition from physical aggression to verbal aggression); and (c) the potentiation of pragmatic principles governing conversation, including, but not limited to, turn-taking and inferential abilities. Our core hypothesis is that the reduction in reactive aggression, one of the key factors in self-domestication processes, enabled us to fully exploit our cognitive and interactional potential as applied to linguistic exchanges, and ultimately to evolve a specific form of communication governed by persuasive reciprocity-a trait of human conversation characterized by both competition and cooperation. In turn, both early crude forms of language, well suited for verbal aggression/insult, and later more sophisticated forms of language, well suited for persuasive reciprocity, significantly contributed to the resolution and reduction of (physical) aggression, thus having a return effect on the self-domestication processes. Supporting evidence for our proposal, as well as grounds for further testing, comes mainly from the consideration of cognitive disorders, which typically simultaneously present abnormal features of self-domestication (including aggressive behavior) and problems with pragmatics and social functioning. While various approaches to language evolution typically reduce it to a single factor, our approach considers language evolution as a multifactorial process, with each player acting upon the other, engaging in an intense mutually reinforcing feedback loop. Moreover, we see language evolution as a gradual process, continuous with the pre-linguistic cognitive abilities, which were engaged in a positive feedback loop with linguistic innovations, and where gene-culture co-evolution and cultural niche construction were the main driving forces.
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Affiliation(s)
- Antonio Benítez-Burraco
- Department of Spanish, Linguistics and Theory of Literature (Linguistics), Faculty of Philology, University of Seville
| | - Francesco Ferretti
- Department of Philosophy, Communication and Performing Arts. Roma Tre University
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45
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dos Santos M, Knoch D. Explaining the evolution of parochial punishment in humans. EVOL HUM BEHAV 2021. [DOI: 10.1016/j.evolhumbehav.2020.10.002] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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DeTroy SE, Ross CT, Cronin KA, van Leeuwen EJ, Haun DB. Cofeeding tolerance in chimpanzees depends on group composition: a longitudinal study across four communities. iScience 2021; 24:102175. [PMID: 33733060 PMCID: PMC7940988 DOI: 10.1016/j.isci.2021.102175] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2020] [Revised: 09/21/2020] [Accepted: 02/08/2021] [Indexed: 01/26/2023] Open
Abstract
Social tolerance is generally treated as a stable, species-specific characteristic. Recent research, however, has questioned this position and emphasized the importance of intraspecific variation. We investigate the temporal stability of social tolerance in four groups of sanctuary-housed chimpanzees over eight years using a commonly employed measure: experimental cofeeding tolerance. We then draw on longitudinal data on the demographic composition of each group to identify the factors associated with cofeeding tolerance. We find appreciable levels of variation in cofeeding tolerance across both groups and years that correspond closely to changes in group-level demographic composition. For example, cofeeding tolerance is lower when there are many females with young infants. These results suggest that social tolerance may be a "responding trait" of chimpanzee sociality, reflecting individual-level behavioral responses to social changes. Additional, experimental research is needed to better model the causal drivers of social tolerance within and among species.
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Affiliation(s)
- Sarah E. DeTroy
- Max Planck Institute for Evolutionary Anthropology, Deutscher Platz 6, 04103 Leipzig, Germany
- Department for Early Child Development and Culture, Faculty of Education, Leipzig University, Jahnallee 59, 04109 Leipzig, Germany
| | - Cody T. Ross
- Max Planck Institute for Evolutionary Anthropology, Deutscher Platz 6, 04103 Leipzig, Germany
| | - Katherine A. Cronin
- Animal Welfare Science Program, Lincoln Park Zoo, 2001 N Clark St, Chicago, IL 60614, USA
- Committee on Evolutionary Biology, University of Chicago, 1025 E. 57th Street, Chicago, IL 60637, USA
| | - Edwin J.C. van Leeuwen
- Max Planck Institute for Evolutionary Anthropology, Deutscher Platz 6, 04103 Leipzig, Germany
- Behavioural Ecology and Ecophysiology Group, Department of Biology, University of Antwerp, Universiteitsplein 1, 2610 Antwerp, Belgium
- Centre for Research and Conservation, Royal Zoological Society of Antwerp, Koningin Astridplein 20-26, 2018 Antwerp, Belgium
| | - Daniel B.M. Haun
- Max Planck Institute for Evolutionary Anthropology, Deutscher Platz 6, 04103 Leipzig, Germany
- Department for Early Child Development and Culture, Faculty of Education, Leipzig University, Jahnallee 59, 04109 Leipzig, Germany
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Cheng L, Lucchesi S, Mundry R, Samuni L, Deschner T, Surbeck M. Variation in aggression rates and urinary cortisol levels indicates intergroup competition in wild bonobos. Horm Behav 2021; 128:104914. [PMID: 33373622 DOI: 10.1016/j.yhbeh.2020.104914] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/04/2020] [Revised: 12/09/2020] [Accepted: 12/10/2020] [Indexed: 01/08/2023]
Abstract
Intergroup competition is a widespread phenomenon across taxa and groups typically compete over access to limited resources, such as food and mates. Such competition may be quantified by changes in individuals' behavioral and physiological status in response to intergroup encounters (IGEs). Bonobos, one of our closest living relatives, are often regarded as xenophilic and exhibit high tolerance towards out-group individuals. This tolerance between groups may still be accompanied by intergroup competition over resources. We hereby compared variation in aggression rates and urinary cortisol levels of bonobos during and outside contexts of IGEs in the Kokolopori Bonobo Reserve and investigated whether food and mate availability influenced males' and females' aggression and cortisol levels, when controlling for dominance rank and the number of individuals present. We found that although females had higher aggression rates and urinary cortisol levels during than outside contexts of IGEs, these increases were not related to food availability or changes in between-group dynamics when maximally tumescent females were present, rather than absent. Furthermore, males showed higher aggression rates and urinary cortisol levels during than outside contexts of IGEs. However, males' responses during IGEs were not related to the presence of maximally tumescent females and food availability. Taken together, while competition intensified during seemingly tolerant IGEs in bonobos, such competition was unrelated to short-term changes in food and mate availability. Despite physical and physiological costs of aggression, bonobos associate with out-group individuals frequently and for extended periods. This suggests potential benefits of bonobo intergroup associations.
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Affiliation(s)
- Leveda Cheng
- Department of Human Evolutionary Biology, Harvard University, 11 Divinity Avenue, Cambridge, MA 02138, USA; Max Planck Institute for Evolutionary Anthropology, Deutscher Platz 6, 04103 Leipzig, Germany.
| | - Stefano Lucchesi
- Department of Human Evolutionary Biology, Harvard University, 11 Divinity Avenue, Cambridge, MA 02138, USA; Max Planck Institute for Evolutionary Anthropology, Deutscher Platz 6, 04103 Leipzig, Germany
| | - Roger Mundry
- Max Planck Institute for Evolutionary Anthropology, Deutscher Platz 6, 04103 Leipzig, Germany
| | - Liran Samuni
- Department of Human Evolutionary Biology, Harvard University, 11 Divinity Avenue, Cambridge, MA 02138, USA; Max Planck Institute for Evolutionary Anthropology, Deutscher Platz 6, 04103 Leipzig, Germany
| | - Tobias Deschner
- Department of Primatology, Max Planck Institute for Evolutionary Anthropology, Deutscher Platz 6, 04103 Leipzig, Germany
| | - Martin Surbeck
- Department of Human Evolutionary Biology, Harvard University, 11 Divinity Avenue, Cambridge, MA 02138, USA; Max Planck Institute for Evolutionary Anthropology, Deutscher Platz 6, 04103 Leipzig, Germany
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Wilson ML. Insights into human evolution from 60 years of research on chimpanzees at Gombe. EVOLUTIONARY HUMAN SCIENCES 2021; 3:e8. [PMID: 33604500 PMCID: PMC7886264 DOI: 10.1017/ehs.2021.2] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023] Open
Abstract
Sixty years of research on chimpanzees (Pan troglodytes) at Gombe National Park, Tanzania have revealed many similarities with human behaviour, including hunting, tool use, and coalitionary killing. The close phylogenetic relationship between chimpanzees and humans suggests that these traits were present in the last common ancestor of Pan and Homo (LCAPH). However, findings emerging from studies of our other closest living relative, the bonobo (Pan paniscus), indicate that either bonobos are derived in these respects, or the many similarities between chimpanzees and humans evolved convergently. In either case, field studies provide opportunities to test hypotheses for how and why our lineage has followed its peculiar path through the adaptive landscape. Evidence from primate field studies suggests that the hominin path depends on our heritage as apes: inefficient quadrupeds with grasping hands, orthograde posture, and digestive systems that require high quality foods. Key steps along this path include: (1) changes in diet; (2) increased use of tools; (3) bipedal gait; (4) multilevel societies; (5) collective foraging, including a sexual division of labor and extensive food transfers; and (6) language. Here I consider some possible explanations for these transitions, with an emphasis on contributions from Gombe.
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Affiliation(s)
- Michael Lawrence Wilson
- Department of Anthropology, University of Minnesota, 395 Humphrey Center, 301 19th Ave. S., Minneapolis, MN55455, USA
- Department of Ecology, Evolution and Behavior, University of Minnesota, 140 Gortner Laboratory, 1479 Gortner Avenue, Saint Paul, MN55108, USA
- Institute on the Environment, University of Minnesota, 1954 Buford Avenue, Saint Paul, MN55108, USA
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Spikins P, French JC, John-Wood S, Dytham C. Theoretical and Methodological Approaches to Ecological Changes, Social Behaviour and Human Intergroup Tolerance 300,000 to 30,000 BP. JOURNAL OF ARCHAEOLOGICAL METHOD AND THEORY 2021; 28:53-75. [PMID: 33679119 PMCID: PMC7891228 DOI: 10.1007/s10816-020-09503-5] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Accepted: 12/15/2020] [Indexed: 05/13/2023]
Abstract
UNLABELLED Archaeological evidence suggests that important shifts were taking place in the character of human social behaviours 300,000 to 30,000 years ago. New artefact types appear and are disseminated with greater frequency. Transfers of both raw materials and finished artefacts take place over increasing distances, implying larger scales of regional mobility and more frequent and friendlier interactions between different communities. Whilst these changes occur during a period of increasing environmental variability, the relationship between ecological changes and transformations in social behaviours is elusive. Here, we explore a possible theoretical approach and methodology for understanding how ecological contexts can influence selection pressures acting on intergroup social behaviours. We focus on the relative advantages and disadvantages of intergroup tolerance in different ecological contexts using agent-based modelling (ABM). We assess the relative costs and benefits of different 'tolerance' levels in between-group interactions on survival and resource exploitation in different environments. The results enable us to infer a potential relationship between ecological changes and proposed changes in between-group behavioural dynamics. We conclude that increasingly harsh environments may have driven changes in hormonal and emotional responses in humans leading to increasing intergroup tolerance, i.e. transformations in social behaviour associated with 'self-domestication'. We argue that changes in intergroup tolerance is a more parsimonious explanation for the emergence of what has been seen as 'modern human behaviour' than changes in hard aspects of cognition or other factors such as cognitive adaptability or population size. SUPPLEMENTARY INFORMATION The online version contains supplementary material available at 10.1007/s10816-020-09503-5.
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Affiliation(s)
- Penny Spikins
- Department of Archaeology, Archaeology PalaeoHub, University of York, York, YO10 5DD UK
| | - Jennifer C. French
- Department of Archaeology, Classics, and Egyptology, University of Liverpool, Liverpool, L69 7WZ UK
| | - Seren John-Wood
- York Cross-disciplinary Centre for Systems Analysis (YCCSA) Internship Programme, University of York, York, UK
- University College London, London, UK
| | - Calvin Dytham
- Department of Biology, University of York, York, YO10 5DD UK
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Borgerhoff Mulder M, Caro T, Ngwali AS. A silver lining to REDD: Institutional growth despite programmatic failure. CONSERVATION SCIENCE AND PRACTICE 2020. [DOI: 10.1111/csp2.312] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022] Open
Affiliation(s)
- Monique Borgerhoff Mulder
- Department of Human Behavior, Ecology and Culture Max Planck Institute for Evolutionary Anthropology Leipzig Germany
- Department of Anthropology University of California at Davis Davis California USA
| | - Tim Caro
- School of Biological Sciences University of Bristol Bristol United Kingdom
| | - Assa Sharif Ngwali
- Department of Forestry and Non‐Renewable Natural Resources Zanzibar Tanzania
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