1
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van Leeuwen EJC, DeTroy SE, Haun DBM, Call J. Chimpanzees use social information to acquire a skill they fail to innovate. Nat Hum Behav 2024; 8:891-902. [PMID: 38448718 PMCID: PMC11132989 DOI: 10.1038/s41562-024-01836-5] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2023] [Accepted: 01/22/2024] [Indexed: 03/08/2024]
Abstract
Cumulative cultural evolution has been claimed to be a uniquely human phenomenon pivotal to the biological success of our species. One plausible condition for cumulative cultural evolution to emerge is individuals' ability to use social learning to acquire know-how that they cannot easily innovate by themselves. It has been suggested that chimpanzees may be capable of such know-how social learning, but this assertion remains largely untested. Here we show that chimpanzees use social learning to acquire a skill that they failed to independently innovate. By teaching chimpanzees how to solve a sequential task (one chimpanzee in each of the two tested groups, n = 66) and using network-based diffusion analysis, we found that 14 naive chimpanzees learned to operate a puzzle box that they failed to operate during the preceding three months of exposure to all necessary materials. In conjunction, we present evidence for the hypothesis that social learning in chimpanzees is necessary and sufficient to acquire a new, complex skill after the initial innovation.
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Affiliation(s)
- Edwin J C van Leeuwen
- Animal Behaviour and Cognition, Department of Biology, Utrecht University, Utrecht, the Netherlands.
- Department of Comparative Cultural Psychology, Max Planck Institute for Evolutionary Anthropology, Leipzig, Germany.
- Centre for Research and Conservation, Royal Zoological Society of Antwerp, Antwerp, Belgium.
| | - Sarah E DeTroy
- Department of Comparative Cultural Psychology, Max Planck Institute for Evolutionary Anthropology, Leipzig, Germany
| | - Daniel B M Haun
- Department of Comparative Cultural Psychology, Max Planck Institute for Evolutionary Anthropology, Leipzig, Germany
| | - Josep Call
- School of Psychology & Neuroscience, University of St Andrews, St Andrews, UK
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2
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Rosati AG, Sabbi KH, Bryer MAH, Barnes P, Rukundo J, Mukungu T, Sekulya P, Ampeire I, Aligumisiriza H, Kyama S, Masereka J, Nabukeera W, Okello A, Waiga B, Atwijuze S, Peña NC, Cantwell A, Felsche E, Flores-Mendoza K, Mohamed S, Monroe I, Mulhinch M, O'Gorman K, Salamango J, Shamah R, Otali E, Wrangham RW, Machanda ZP. Observational approaches to chimpanzee behavior in an African sanctuary: Implications for research, welfare, and capacity-building. Am J Primatol 2023; 85:e23534. [PMID: 37461356 PMCID: PMC10530331 DOI: 10.1002/ajp.23534] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2023] [Revised: 07/01/2023] [Accepted: 07/08/2023] [Indexed: 08/04/2023]
Abstract
Research in African ape sanctuaries has emerged as an important context for our understanding of comparative cognition and behavior. While much of this work has focused on experimental studies of cognition, these animals semi-free-range in forest habitats and therefore can also provide important information about the behavior of primates in socioecologically-relevant naturalistic contexts. In this "New Approaches" article, we describe a project where we implemented a synthetic program of observational data collection at Ngamba Island Chimpanzee Sanctuary in Uganda, directly modeled after long-term data collection protocols at the Kibale Chimpanzee Project in Uganda, a wild chimpanzee field site. The foundation for this project was a strong partnership between sanctuary staff, field site staff, and external researchers. We describe how we developed a data-collection protocol through discussion and collaboration among these groups, and trained sanctuary caregivers to collect novel observational data using these protocols. We use these data as a case study to examine: (1) how behavioral observations in sanctuaries can inform primate welfare and care practices, such as by understanding aggression within the group; (2) how matched observational protocols across sites can inform our understanding of primate behavior across different contexts, including sex differences in social relationships; and (3) how more robust collaborations between foreign researchers and local partners can support capacity-building in primate range countries, along with mentoring and training students more broadly.
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Affiliation(s)
- Alexandra G Rosati
- Department of Psychology, University of Michigan, Ann Arbor, Michigan, USA
- Department of Anthropology, University of Michigan, Ann Arbor, Michigan, USA
| | - Kris H Sabbi
- Department of Anthropology, Tufts University, Medford, Massachusetts, USA
- Kibale Chimpanzee Project, Kibale National Park, Uganda
| | - Margaret A H Bryer
- Department of Psychology, University of Michigan, Ann Arbor, Michigan, USA
| | - Paige Barnes
- Department of Psychology, University of Michigan, Ann Arbor, Michigan, USA
| | - Joshua Rukundo
- Ngamba Island Chimpanzee Sanctuary/Chimpanzee Trust, Entebbe, Uganda
| | - Titus Mukungu
- Ngamba Island Chimpanzee Sanctuary/Chimpanzee Trust, Entebbe, Uganda
| | - Phillip Sekulya
- Ngamba Island Chimpanzee Sanctuary/Chimpanzee Trust, Entebbe, Uganda
| | - Innocent Ampeire
- Ngamba Island Chimpanzee Sanctuary/Chimpanzee Trust, Entebbe, Uganda
| | | | - Stanley Kyama
- Ngamba Island Chimpanzee Sanctuary/Chimpanzee Trust, Entebbe, Uganda
| | - Joseph Masereka
- Ngamba Island Chimpanzee Sanctuary/Chimpanzee Trust, Entebbe, Uganda
| | - Winnie Nabukeera
- Ngamba Island Chimpanzee Sanctuary/Chimpanzee Trust, Entebbe, Uganda
| | - Amos Okello
- Ngamba Island Chimpanzee Sanctuary/Chimpanzee Trust, Entebbe, Uganda
| | - Boris Waiga
- Ngamba Island Chimpanzee Sanctuary/Chimpanzee Trust, Entebbe, Uganda
| | | | | | - Averill Cantwell
- Department of Psychology, University of Michigan, Ann Arbor, Michigan, USA
| | - Elisa Felsche
- Department of Psychology, University of Michigan, Ann Arbor, Michigan, USA
- Department of Comparative Cultural Psychology, Max Planck Institute for Evolutionary Anthropology, Leipzig, Germany
| | | | - Safa Mohamed
- Department of Psychology, University of Michigan, Ann Arbor, Michigan, USA
| | - Isabelle Monroe
- Department of Psychology, University of Michigan, Ann Arbor, Michigan, USA
| | - Megan Mulhinch
- Department of Psychology, University of Michigan, Ann Arbor, Michigan, USA
- Department of Psychology, University of California San Diego, La Jolla, California, USA
| | - Kathleen O'Gorman
- Department of Psychology, University of Michigan, Ann Arbor, Michigan, USA
| | - Julia Salamango
- Department of Psychology, University of Michigan, Ann Arbor, Michigan, USA
| | - Rayna Shamah
- Department of Psychology, University of Michigan, Ann Arbor, Michigan, USA
| | - Emily Otali
- Kibale Chimpanzee Project, Kibale National Park, Uganda
| | - Richard W Wrangham
- Department of Biology, Tufts University, Medford, Massachusetts, USA
- Department of Human Evolutionary Biology, Harvard University, Cambridge, Massachusetts, USA
| | - Zarin P Machanda
- Department of Anthropology, Tufts University, Medford, Massachusetts, USA
- Department of Biology, Tufts University, Medford, Massachusetts, USA
- Kibale Chimpanzee Project, Kibale National Park, Uganda
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3
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Chimpanzee communities differ in their inter- and intrasexual social relationships. Learn Behav 2023; 51:48-58. [PMID: 36725763 PMCID: PMC9971155 DOI: 10.3758/s13420-023-00570-8] [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] [Accepted: 01/05/2023] [Indexed: 02/03/2023]
Abstract
Male and female human social bonding strategies are culturally shaped, in addition to being genetically rooted. Investigating nonhuman primate bonding strategies across sex groups allows researchers to assess whether, as with humans, they are shaped by the social environment or whether they are genetically predisposed. Studies of wild chimpanzees show that in some communities males have strong bonds with other males, whereas in others, females form particularly strong intrasex bonds, potentially indicative of cultural differences across populations. However, excluding genetic or ecological explanations when comparing different wild populations is difficult. Here, we applied social network analysis to examine male and female social bonds in two neighbouring semiwild chimpanzee groups of comparable ecological conditions and subspecies compositions, but that differ in demographic makeup. Results showed differences in bonding strategies across the two groups. While female-female party co-residence patterns were significantly stronger in Group 1 (which had an even distribution of males and females) than in Group 2 (which had a higher proportion of females than males), there were no such differences for male-male or male-female associations. Conversely, female-female grooming bonds were stronger in Group 2 than in Group 1. We also found that, in line with captive studies but contrasting research with wild chimpanzees, maternal kinship strongly predicted proximity and grooming patterns across the groups. Our findings suggest that, as with humans, male and female chimpanzee social bonds are influenced by the specific social group they live in, rather than predisposed sex-based bonding strategies.
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4
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van Leeuwen EJ, Hoppitt W. Biased cultural transmission of a social custom in chimpanzees. SCIENCE ADVANCES 2023; 9:eade5675. [PMID: 36791187 PMCID: PMC9931211 DOI: 10.1126/sciadv.ade5675] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 09/07/2022] [Accepted: 01/10/2023] [Indexed: 06/18/2023]
Abstract
Cultural transmission studies in animals have predominantly focused on identifying between-group variation in tool-use techniques, while immaterial cultures remain understudied despite their potential for highlighting similarities between human and animal culture. Here, using long-term data from two chimpanzee communities, we tested whether one of chimpanzees' most enigmatic social customs-the grooming handclasp-is culturally transmitted by investigating the influence of well-documented human transmission biases on their variational preferences. After identifying differences in style preferences between the communities, we show that older and dominant individuals exert more influence over their partners' handclasp styles. Mothers were equally likely to influence their offspring's preferences as nonkin, indicating that styles are transmitted both vertically and obliquely. Last, individuals gradually converged on the group style, suggesting that conformity guides chimpanzees' handclasp preferences. Our findings show that chimpanzees' social lives are influenced by cultural transmission biases that hitherto were thought to be uniquely human.
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Affiliation(s)
- Edwin J. C. van Leeuwen
- Animal Behaviour and Cognition, Department of Biology, Utrecht University, Utrecht, the Netherlands
- Centre for Research and Conservation, Royal Zoological Society of Antwerp, K. Astridplein 26, B 2018 Antwerp, Belgium
- Department of Comparative Cultural Psychology, Max Planck Institute for Evolutionary Anthropology, Deutscher Platz 6, 04103 Leipzig, Germany
| | - William Hoppitt
- Department of Biological Sciences, Royal Holloway, University of London, Egham, UK
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5
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Goldsborough Z, Schel AM, van Leeuwen EJC. Chimpanzees communicate to coordinate a cultural practice. Proc Biol Sci 2023; 290:20221754. [PMID: 36651045 PMCID: PMC9845976 DOI: 10.1098/rspb.2022.1754] [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] [Indexed: 01/19/2023] Open
Abstract
Human culture thrives by virtue of communication, yet whether communication plays an influential role in the cultural lives of other animals remains understudied. Here, we investigated whether chimpanzees use communication to engage in a cultural practice by analysing grooming handclasp (GHC) interactions-a socio-cultural behaviour requiring interindividual coordination for successful execution. Previous accounts attributed GHC initiations to behavioural shaping, whereby the initiator physically moulds the partner's arm into the desired GHC posture. Using frame-by-frame analysis and matched-control methodology, we find that chimpanzees do not only shape their partner's posture (22%), but also use gestural communication to initiate GHC (44%), which requires an active and synchronized response from the partner. Moreover, in a third (34%) of the GHC initiations, the requisite coordination was achieved by seemingly effortless synchrony. Lastly, using a longitudinal approach, we find that for GHC initiations, communication occurs more frequently than shaping in experienced dyads and less in mother-offspring dyads. These findings are consistent with ontogenetic ritualization, thereby reflecting first documentation of chimpanzees communicating to coordinate a cultural practice. We conclude that chimpanzees show interactional flexibility in the socio-cultural domain, opening the possibility that the interplay between communication and culture is rooted in our deep evolutionary history.
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Affiliation(s)
- Zoë Goldsborough
- Department for the Ecology of Animal Societies, Max Planck Institute of Animal Behavior, Bücklestraße 5a, Konstanz, 78467, Germany,Animal Behaviour and Cognition, Department of Biology, Utrecht University, Padualaan 8, Utrecht, CA 3584, The Netherlands,Department of Biology, University of Konstanz, Universitätsstraße 10, Konstanz 78464, Germany
| | - Anne Marijke Schel
- Animal Behaviour and Cognition, Department of Biology, Utrecht University, Padualaan 8, Utrecht, CA 3584, The Netherlands
| | - Edwin J. C. van Leeuwen
- Animal Behaviour and Cognition, Department of Biology, Utrecht University, Padualaan 8, Utrecht, CA 3584, The Netherlands,Behavioral 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, K. Astridplein 26, B 2018 Antwerp, Belgium
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6
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Escribano D, Doldán-Martelli V, Cronin KA, Haun DBM, van Leeuwen EJC, Cuesta JA, Sánchez A. Chimpanzees organize their social relationships like humans. Sci Rep 2022; 12:16641. [PMID: 36198695 PMCID: PMC9534840 DOI: 10.1038/s41598-022-20672-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2022] [Accepted: 09/16/2022] [Indexed: 12/05/2022] Open
Abstract
Human relationships are structured in a set of layers, ordered from higher (intimate relationships) to lower (acquaintances) emotional and cognitive intensity. This structure arises from the limits of our cognitive capacity and the different amounts of resources required by different relationships. However, it is unknown whether nonhuman primate species organize their affiliative relationships following the same pattern. We here show that the time chimpanzees devote to grooming other individuals is well described by the same model used for human relationships, supporting the existence of similar social signatures for both humans and chimpanzees. Furthermore, the relationship structure depends on group size as predicted by the model, the proportion of high-intensity connections being larger for smaller groups.
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Affiliation(s)
- Diego Escribano
- Grupo Interdisciplinar de Sistemas Complejos (GISC), Departamento de Matemáticas, Universidad Carlos III de Madrid, 28911, Leganés, Spain
| | - Victoria Doldán-Martelli
- Grupo Interdisciplinar de Sistemas Complejos (GISC), Departamento de Matemáticas, Universidad Carlos III de Madrid, 28911, Leganés, Spain
| | - Katherine A Cronin
- Animal Welfare Science Program, Lincoln Park Zoo, Chicago, IL, 60614, USA.,Lester E. Fisher Center for the Study and Conservation of Apes, Lincoln Park Zoo, Chicago, IL, 60614, USA
| | - Daniel B M Haun
- Department for Comparative Cultural Psychology, Max Planck Institute for Evolutionary Anthropology, Deutscher Platz 6, 04103, Leipzig, Germany.,Leipzig Research Centre for Early Child Development, Leipzig University, Jahnallee 59, 04109, Leipzig, Germany
| | - Edwin J C van Leeuwen
- Department for Comparative Cultural Psychology, Max Planck Institute for Evolutionary Anthropology, Deutscher Platz 6, 04103, Leipzig, Germany.,Animal Behaviour and Cognition, Department of Biology, University Utrecht, 3584 CH, Utrecht, The Netherlands
| | - José A Cuesta
- Grupo Interdisciplinar de Sistemas Complejos (GISC), Departamento de Matemáticas, Universidad Carlos III de Madrid, 28911, Leganés, Spain.,Instituto de Biocomputación y Física de Sistemas Complejos (BIFI), Universidad de Zaragoza, 50018, Zaragoza, Spain
| | - Angel Sánchez
- Grupo Interdisciplinar de Sistemas Complejos (GISC), Departamento de Matemáticas, Universidad Carlos III de Madrid, 28911, Leganés, Spain. .,Instituto de Biocomputación y Física de Sistemas Complejos (BIFI), Universidad de Zaragoza, 50018, Zaragoza, Spain.
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7
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Formaux A, Paleressompoulle D, Fagot J, Claidière N. The experimental emergence of convention in a non-human primate. Philos Trans R Soc Lond B Biol Sci 2022; 377:20200310. [PMID: 34894743 PMCID: PMC8666916 DOI: 10.1098/rstb.2020.0310] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2021] [Accepted: 08/02/2021] [Indexed: 02/02/2023] Open
Abstract
Conventions form an essential part of human social and cultural behaviour and may also be important to other animal societies. Yet, despite the wealth of evidence that has accumulated for culture in non-human animals, we know surprisingly little about non-human conventions beyond a few rare examples. We follow the literature in behavioural ecology and evolution and define conventions as systematic behaviours that solve a coordination problem in which two or more individuals need to display complementary behaviour to obtain a mutually beneficial outcome. We start by discussing the literature on conventions in non-human primates from this perspective and conclude that all the ingredients for conventions to emerge are present and therefore that they ought to be more frequently observed. We then probe the emergence of conventions by using a unique novel experimental system in which pairs of Guinea baboons (Papio papio) can voluntarily participate together in touchscreen-based cognitive testing and we show that conventions readily emerge in our experimental set-up and that they share three fundamental properties of human conventions (arbitrariness, stability and efficiency). These results question the idea that observational learning, and imitation in particular, is necessary to establish conventions; they suggest that positive reinforcement is enough. This article is part of a discussion meeting issue 'The emergence of collective knowledge and cumulative culture in animals, humans and machines'.
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Affiliation(s)
- Anthony Formaux
- Laboratoire de Psychologie Cognitive, UMR7290, Université Aix-Marseille/CNRS, 13331 Marseille, France
- Station de Primatologie-Celphedia, CNRS UAR846, Rousset, France
| | - Dany Paleressompoulle
- Laboratoire de Psychologie Cognitive, UMR7290, Université Aix-Marseille/CNRS, 13331 Marseille, France
| | - Joël Fagot
- Laboratoire de Psychologie Cognitive, UMR7290, Université Aix-Marseille/CNRS, 13331 Marseille, France
- Station de Primatologie-Celphedia, CNRS UAR846, Rousset, France
- Institute for Language, Communication and the Brain, Université Aix-Marseille, CNRS, Aix-en-Provence, France
| | - Nicolas Claidière
- Laboratoire de Psychologie Cognitive, UMR7290, Université Aix-Marseille/CNRS, 13331 Marseille, France
- Station de Primatologie-Celphedia, CNRS UAR846, Rousset, France
- Institute for Language, Communication and the Brain, Université Aix-Marseille, CNRS, Aix-en-Provence, France
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8
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Abstract
Culture is a hallmark of the human species, both in terms of the transmission of material inventions (e.g. tool manufacturing) and the adherence to social conventions (e.g. greeting mannerisms). While material culture has been reported across the animal kingdom, indications of social culture in animals are limited. Moreover, there is a paucity of evidencing cultural stability in animals. Here, based on a large dataset spanning 12 years, I show that chimpanzees adhere to arbitrary group-specific handclasp preferences that cannot be explained by genetics or the ecological environment. Despite substantial changes in group compositions across the study period, and all chimpanzees having several behavioural variants in their repertoires, chimpanzees showed and maintained the within-group homogeneity and between-group heterogeneity that are so characteristic of the cultural phenomenon in the human species. These findings indicate that human culture, including its arbitrary social conventions and long-term stability, is rooted in our evolutionary history.
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Affiliation(s)
- Edwin J. C. van Leeuwen
- Department for Comparative Cultural Psychology, Max Planck Institute for Evolutionary Anthropology, Deutscher Platz 6, 04103, Leipzig, Germany
- Behavioral 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
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9
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van Boekholt B, van de Waal E, Sterck EH. Organized to learn: the influence of social structure on social learning opportunities in a group. iScience 2021; 24:102117. [PMID: 33659880 PMCID: PMC7890404 DOI: 10.1016/j.isci.2021.102117] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022] Open
Abstract
Social learning, which is a mechanism that allows an individual to acquire skills from other individuals, occurs in a social context. Therefore, factors that influence social context, like social structure, will impact social learning opportunities. This review explores how features of social structure affect social learning opportunities in primates, either through their relationship with social tolerance or through the number of social learning models. Features that are investigated in this review and that we hypothesize affect social learning opportunities are parental investment, dominance hierarchy, nepotism, social bonds, dispersal, group size, fission-fusion dynamics, and sex ratio. For most of these features we find evidence, but support varies. Of all primate species, only humans show all the requirements of an optimal social structure to promote social learning. Future research into social learning and culture should not overlook the social context in which it takes place.
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Affiliation(s)
- Bas van Boekholt
- Animal Ecology, Department of Biology, Utrecht University, Utrecht, 3584CH The Netherlands
- Department of Comparative Biocognition, Institute of Cognitive Science, University of Osnabrück, Osnabrück, 49074, Germany
| | - Erica van de Waal
- Department of Ecology and Evolution, University of Lausanne, Lausanne, 1015, Switzerland
| | - Elisabeth H.M. Sterck
- Animal Ecology, Department of Biology, Utrecht University, Utrecht, 3584CH The Netherlands
- Animal Science Department, Biomedical Primate Research Centre, Rijswijk, 2288GJ, the Netherlands
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10
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Bandini E, Harrison RA. Innovation in chimpanzees. Biol Rev Camb Philos Soc 2020; 95:1167-1197. [DOI: 10.1111/brv.12604] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2019] [Revised: 04/01/2020] [Accepted: 04/03/2020] [Indexed: 12/26/2022]
Affiliation(s)
- Elisa Bandini
- Department for Early Prehistory and Quaternary Ecology The University of Tübingen Tübingen Germany
| | - Rachel A. Harrison
- Department of Ecology and Evolution University of Lausanne Lausanne Switzerland
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11
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Abstract
While non-human primate studies have long been conducted in laboratories, and more recently at zoological parks, sanctuaries are increasingly considered a viable setting for research. Accredited sanctuaries in non-range countries house thousands of primates formerly used as subjects of medical research, trained performers or personal pets. In range countries, however, sanctuaries typically house orphaned primates confiscated from illegal poaching and the bushmeat and pet trafficking trades. Although the primary mission of these sanctuaries is to rescue and rehabilitate residents, many of these organizations are increasingly willing to participate in non-invasive research. Notably, from a scientific standpoint, most sanctuaries provide potential advantages over traditional settings, such as large, naturalistic physical and social environments which may result in more relevant models of primates' free-ranging wild counterparts than other captive settings. As a result, an impressive scope of research in the fields of primate behaviour, cognition, veterinary science, genetics and physiology have been studied in sanctuaries. In this review, we examine the range and form of research that has been conducted at accredited sanctuaries around the world. We also describe the potential challenges of sanctuary-based work and the considerations that external researchers may face when deciding to collaborate with primate sanctuaries on their research projects.
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Affiliation(s)
- Stephen R Ross
- Lester E. Fisher Center for the Study and Conservation of Apes, Lincoln Park Zoo, 2001 North Clark St., Chicago, IL 60614, USA
| | - Jesse G Leinwand
- Lester E. Fisher Center for the Study and Conservation of Apes, Lincoln Park Zoo, 2001 North Clark St., Chicago, IL 60614, USA
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12
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Abstract
Intergroup variation (IGV) refers to variation between different groups of the same species. While its existence in the behavioural realm has been expected and evidenced, the potential effects of IGV are rarely considered in studies that aim to shed light on the evolutionary origins of human socio-cognition, especially in our closest living relatives—the great apes. Here, by taking chimpanzees as a point of reference, we argue that (i) IGV could plausibly explain inconsistent research findings across numerous topics of inquiry (experimental/behavioural studies on chimpanzees), (ii) understanding the evolutionary origins of behaviour requires an accurate assessment of species' modes of behaving across different socio-ecological contexts, which necessitates a reliable estimation of variation across intraspecific groups, and (iii) IGV in the behavioural realm is increasingly likely to be expected owing to the progressive identification of non-human animal cultures. With these points, and by extrapolating from chimpanzees to generic guidelines, we aim to encourage researchers to explicitly consider IGV as an explanatory variable in future studies attempting to understand the socio-cognitive and evolutionary determinants of behaviour in group-living animals.
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Affiliation(s)
- Stephan P Kaufhold
- Department of Cognitive Science, University of California San Diego, 9500 Gilman Drive, La Jolla, San Diego, CA 92093, USA
| | - Edwin J C van Leeuwen
- Behavioral Ecology and Ecophysiology Group, Department of Biology, University of Antwerp, Universiteitsplein 1, 2610, Wilrijk, Antwerp, Belgium.,Centre for Research and Conservation, Royal Zoological Society of Antwerp, K. Astridplein 26, 2018 Antwerp, Belgium.,Max Planck Institute for Psycholinguistics, Wundtlaan 1, 6525 XD Nijmegen, The Netherlands
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13
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Abstract
In recent decades, a burgeoning literature has documented the cultural transmission of behavior through social learning in numerous vertebrate and invertebrate species. One meaning of “cultural evolution in animals” refers to these discoveries, and I present an overview of key findings. I then address the other meaning of the term focused on cultural changes within a lineage. Such changes in humans, described as “cumulative cultural evolution,” have been spectacular, but relatively little attention has yet been paid to the topic in nonhuman animals, other than asserting that the process is unique to humans. A variety of evidence including both controlled experiments and field observations has begun to challenge this view, and in some behavioral domains, notably birdsong, cultural evolution has been studied for many years. In this review, I dissect concepts of cultural evolution and cumulative culture and appraise the accumulating evidence bearing on their nature and significance for evolutionary biology at large.
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Affiliation(s)
- Andrew Whiten
- Centre for Social Learning and Cultural Evolution, School of Psychology and Neuroscience, University of St Andrews, St Andrews KY16 9JP, United Kingdom
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14
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Pika S, Fröhlich M. Gestural acquisition in great apes: the Social Negotiation Hypothesis. Anim Cogn 2019; 22:551-565. [PMID: 29368287 PMCID: PMC6647412 DOI: 10.1007/s10071-017-1159-6] [Citation(s) in RCA: 32] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2017] [Revised: 12/09/2017] [Accepted: 12/29/2017] [Indexed: 02/07/2023]
Abstract
Scientific interest in the acquisition of gestural signalling dates back to the heroic figure of Charles Darwin. More than a hundred years later, we still know relatively little about the underlying evolutionary and developmental pathways involved. Here, we shed new light on this topic by providing the first systematic, quantitative comparison of gestural development in two different chimpanzee (Pan troglodytes verus and Pan troglodytes schweinfurthii) subspecies and communities living in their natural environments. We conclude that the three most predominant perspectives on gestural acquisition-Phylogenetic Ritualization, Social Transmission via Imitation, and Ontogenetic Ritualization-do not satisfactorily explain our current findings on gestural interactions in chimpanzees in the wild. In contrast, we argue that the role of interactional experience and social exposure on gestural acquisition and communicative development has been strongly underestimated. We introduce the revised Social Negotiation Hypothesis and conclude with a brief set of empirical desiderata for instigating more research into this intriguing research domain.
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Affiliation(s)
- Simone Pika
- Department of Primatology, 'Virtual Geesehouse', Max Planck Institute for Evolutionary Anthropology, Deutscher Platz 6, 04103, Leipzig, Germany.
| | - Marlen Fröhlich
- Anthropological Institute and Museum, University of Zürich, Winterthurerstrasse 190, 8057, Zurich, Switzerland
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15
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van Leeuwen EJC, Mundry R, Cronin KA, Bodamer M, Haun DBM. Chimpanzee culture extends beyond matrilineal family units. Curr Biol 2019. [PMID: 28633025 DOI: 10.1016/j.cub.2017.05.003] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
The 'grooming handclasp' is one of the most well-established cultural traditions in chimpanzees. A recent study by Wrangham et al.[1] reduced the cultural scope of grooming-handclasp behavior by showing that grooming-handclasp style convergence is "explained by matrilineal relationship rather than conformity" [1]. Given that we previously reported cultural differences in grooming-handclasp style preferences in captive chimpanzees [2], we tested the alternative view posed by Wrangham et al.[1] in the chimpanzee populations that our original results were based on. Using the same outcome variable as Wrangham et al.[1] - the proportion of high-arm grooming featuring palm-to-palm clasping - we found that matrilineal relationships explained neither within-group homogeneity nor between-group heterogeneity, thereby corroborating our original conclusion that grooming-handclasp behavior can represent a group-level cultural tradition in chimpanzees.
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Affiliation(s)
- Edwin J C van Leeuwen
- University of St. Andrews, School of Psychology and Neuroscience, Westburn Lane, St. Andrews, KY16 9JP, UK; Max Planck Institute for Psycholinguistics, Wundtlaan 1, 6525 XD Nijmegen, the Netherlands.
| | - Roger Mundry
- Max Planck Institute for Evolutionary Anthropology, Deutscher Platz 6, 04103 Leipzig, Germany
| | - Katherine A Cronin
- Lester E. Fisher Center for the Study and Conservation of Apes, Lincoln Park Zoo, Chicago, IL 60614, USA
| | - Mark Bodamer
- Chimfunshi Wildlife Orphanage Trust, Chingola, Zambia
| | - Daniel B M Haun
- University of Leipzig, Department of Early Child Development and Culture and Leipzig Research Center for Early Child Development, D-04109 Leipzig, Germany
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16
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Abstract
Understanding intraspecific variation in sociality is essential for characterizing the flexibility and evolution of social systems, yet its study in nonhuman animals is rare. Here, we investigated whether chimpanzees exhibit population-level differences in sociality that cannot be easily explained by differences in genetics or ecology. We compared social proximity and grooming tendencies across four semiwild populations of chimpanzees living in the same ecological environment over three consecutive years, using both linear mixed models and social network analysis. Results indicated temporally stable, population-level differences in dyadic-level sociality. Moreover, group cohesion measures capturing network characteristics beyond dyadic interactions (clustering, modularity, and social differentiation) showed population-level differences consistent with the dyadic indices. Subsequently, we explored whether the observed intraspecific variation in sociality could be attributed to cultural processes by ruling out alternative sources of variation including the influences of ecology, genetics, and differences in population demographics. We conclude that substantial variation in social behavior exists across neighboring populations of chimpanzees and that this variation is in part shaped by cultural processes.
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17
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Piel AK, Bonnin N, RamirezAmaya S, Wondra E, Stewart FA. Chimpanzees and their mammalian sympatriates in the Issa Valley, Tanzania. Afr J Ecol 2018. [DOI: 10.1111/aje.12570] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Alex K. Piel
- Department of Biological Anthropology University of Cambridge Cambridge UK
- Greater Mahale Ecosystem Research and Conservation Project Dar es Salaam Tanzania
| | - Noemie Bonnin
- Greater Mahale Ecosystem Research and Conservation Project Dar es Salaam Tanzania
| | | | - Eden Wondra
- Greater Mahale Ecosystem Research and Conservation Project Dar es Salaam Tanzania
| | - Fiona A. Stewart
- Department of Biological Anthropology University of Cambridge Cambridge UK
- Greater Mahale Ecosystem Research and Conservation Project Dar es Salaam Tanzania
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18
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Kalan AK, Boesch C. Re-emergence of the leaf clip gesture during an alpha takeover affects variation in male chimpanzee loud calls. PeerJ 2018; 6:e5079. [PMID: 29967740 PMCID: PMC6026532 DOI: 10.7717/peerj.5079] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2018] [Accepted: 06/04/2018] [Indexed: 11/20/2022] Open
Abstract
Loud calls are used by many species as long-distance signals for group defense, mate attraction, and inter- and intragroup spacing. Chimpanzee loud calls, or pant hoots, are used in a variety of contexts including group coordination and during male contests. Here, we observed an alpha male takeover in wild chimpanzees (Pan troglodytes verus) during which the leaf clipping gesture re-emerged after disappearing for almost two years in this community. Leaf clipping only occurred in males and was observed almost exclusively prior to pant hoot vocalizations, as has been observed in other chimpanzee communities of the Taï forest in Côte d'Ivoire. Consequently, we hypothesized that leaf clipping may be important for male-male competition by affecting variation in the acoustic properties of male chimpanzee loud calls. We therefore investigated whether pant hoots preceded by leaf clipping differed acoustically from those without, while also testing the influence of social context on pant hoot variation, namely male dominance rank and hierarchy instability, i.e., before, during and after the alpha takeover. We found that pant hoots preceded by leaf clipping were longer, contained more call elements and drum beats, and lower fundamental and peak frequencies. Moreover, during the alpha takeover pant hoots were shorter, contained fewer drum beats and higher fundamental frequencies. Additionally, pant hoot and aggression rates were also highest during the alpha takeover with leaf clipping more likely to occur on days when pant hooting rates were high. Overall social rank had limited effects on pant hoot variation. We suggest that elevated arousal and aggression during the alpha takeover triggered the re-emergence of leaf clipping and the associated acoustic changes in pant hoots. Further research should focus on the potential mechanisms by which leaf clipping is connected to variation in pant hoots and cross-population comparisons of the behaviour.
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Affiliation(s)
- Ammie K. Kalan
- Department of Primatology, Max Planck Institute for Evolutionary Anthropology, Leipzig, Germany
| | - Christophe Boesch
- Department of Primatology, Max Planck Institute for Evolutionary Anthropology, Leipzig, Germany
- Wild Chimpanzee Foundation, Leipzig, Germany
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19
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Whiten A, van de Waal E. The pervasive role of social learning in primate lifetime development. Behav Ecol Sociobiol 2018; 72:80. [PMID: 29755181 PMCID: PMC5934467 DOI: 10.1007/s00265-018-2489-3] [Citation(s) in RCA: 53] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2017] [Revised: 03/22/2018] [Accepted: 03/29/2018] [Indexed: 11/29/2022]
Abstract
In recent decades, an accelerating research effort has exploited a
substantial diversity of methodologies to garner mounting evidence for social
learning and culture in many species of primate. As in humans, the evidence suggests
that the juvenile phases of non-human primates’ lives represent a period of
particular intensity in adaptive learning from others, yet the relevant research
remains scattered in the literature. Accordingly, we here offer what we believe to
be the first substantial collation and review of this body of work and its
implications for the lifetime behavioral ecology of primates. We divide our analysis
into three main phases: a first phase of learning focused on primary attachment
figures, typically the mother; a second phase of selective learning from a widening
array of group members, including some with expertise that the primary figures may
lack; and a third phase following later dispersal, when a migrant individual
encounters new ecological and social circumstances about which the existing
residents possess expertise that can be learned from. Collating a diversity of
discoveries about this lifetime process leads us to conclude that social learning
pervades primate ontogenetic development, importantly shaping locally adaptive
knowledge and skills that span multiple aspects of the behavioral repertoire.
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Affiliation(s)
- Andrew Whiten
- 1Centre for Social Learning and Cognitive Evolution, and Scottish Primate Research Group, School of Psychology and Neuroscience, University of St Andrews, St Andrews, KY16 9JP UK
| | - Erica van de Waal
- 2Department of Ecology and Evolution, University of Lausanne, 1015 Lausanne, Switzerland
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20
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Roberts AI, Roberts SGB. Convergence and divergence in gesture repertoires as an adaptive mechanism for social bonding in primates. ROYAL SOCIETY OPEN SCIENCE 2017; 4:170181. [PMID: 29291049 PMCID: PMC5717623 DOI: 10.1098/rsos.170181] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 03/03/2017] [Accepted: 10/25/2017] [Indexed: 06/07/2023]
Abstract
A key challenge for primates living in large, stable social groups is managing social relationships. Chimpanzee gestures may act as a time-efficient social bonding mechanism, and the presence (homogeneity) and absence (heterogeneity) of overlap in repertoires in particular may play an important role in social bonding. However, how homogeneity and heterogeneity in the gestural repertoire of primates relate to social interaction is poorly understood. We used social network analysis and generalized linear mixed modelling to examine this question in wild chimpanzees. The repertoire size of both homogeneous and heterogeneous visual, tactile and auditory gestures was associated with the duration of time spent in social bonding behaviour, centrality in the social bonding network and demography. The audience size of partners who displayed similar or different characteristics to the signaller (e.g. same or opposite age or sex category) also influenced the use of homogeneous and heterogeneous gestures. Homogeneous and heterogeneous gestures were differentially associated with the presence of emotional reactions in response to the gesture and the presence of a change in the recipient's behaviour. Homogeneity and heterogeneity of gestural communication play a key role in maintaining a differentiated set of strong and weak social relationships in complex, multilevel societies.
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Affiliation(s)
- Anna Ilona Roberts
- Department of Psychology, University of Chester, Parkgate Road, Chester CH1 4BJ, UK
| | - Sam George Bradley Roberts
- Department of Psychology, University of Chester, Parkgate Road, Chester CH1 4BJ, UK
- School of Natural Sciences and Psychology, Liverpool John Moores University, Byrom Street, Liverpool L3 3AF, UK
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Miller JA, Stanton MA, Lonsdorf EV, Wellens KR, Markham AC, Murray CM. Limited evidence for third-party affiliation during development in wild chimpanzees ( Pan troglodytes schweinfurthii). ROYAL SOCIETY OPEN SCIENCE 2017; 4:170500. [PMID: 28989757 PMCID: PMC5627097 DOI: 10.1098/rsos.170500] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/11/2017] [Accepted: 08/17/2017] [Indexed: 05/11/2023]
Abstract
Examining the ontogeny of conflict-mitigating behaviours in our closest living relatives is an important component of understanding the evolutionary origins of cooperation in our species. In this study, we used 26 years of data to investigate the emergence of third-party affiliation (TPA), defined as affiliative contact given to recipients of aggression by uninvolved bystanders (regardless of initiation), in wild immature eastern chimpanzees (Pan troglodytes schweinfurthii) of Gombe National Park, Tanzania. We also characterized TPA by mothers in the same dataset as an adult benchmark for interpreting immature TPA patterns. In summary, we found that immatures did not express TPA as measured by grooming between the ages of 1.5 and 12.0 years, and that there was limited evidence that immatures expressed TPA via play. We also found that mothers did express TPA to offspring, although mothers did not show TPA towards non-offspring. Cases of TPA by mothers to other adults were too few to analyse separately. These results contrast with findings from captive studies which found that chimpanzees as young as 6 years of age demonstrated TPA. We argue that within-species variation in the expression of TPA, both in immatures and adulthood, provides evidence that the conflict management behaviours of young chimpanzees may be heavily influenced by social, ecological and demographic factors.
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Affiliation(s)
- Jordan A. Miller
- Center for the Advanced Study of Human Paleobiology, The George Washington University, 800 22nd Street, NW, Suite 6000, Washington, DC 20052, USA
| | - Margaret A. Stanton
- Center for the Advanced Study of Human Paleobiology, The George Washington University, 800 22nd Street, NW, Suite 6000, Washington, DC 20052, USA
| | - Elizabeth V. Lonsdorf
- Department of Psychology and Biological Foundations of Behavior Program, Franklin and Marshall College, Lancaster, PA, USA
| | - Kaitlin R. Wellens
- Center for the Advanced Study of Human Paleobiology, The George Washington University, 800 22nd Street, NW, Suite 6000, Washington, DC 20052, USA
| | | | - Carson M. Murray
- Center for the Advanced Study of Human Paleobiology, The George Washington University, 800 22nd Street, NW, Suite 6000, Washington, DC 20052, USA
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22
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Abstract
Discoveries about the cultures and cultural capacities of the great apes have played a leading role in the recognition emerging in recent decades that cultural inheritance can be a significant factor in the lives not only of humans but also of nonhuman animals. This prominence derives in part from these primates being those with whom we share the most recent common ancestry, thus offering clues to the origins of our own thoroughgoing reliance on cumulative cultural achievements. In addition, the intense research focus on these species has spawned an unprecedented diversity of complementary methodological approaches, the results of which suggest that cultural phenomena pervade the lives of these apes, with potentially major implications for their broader evolutionary biology. Here I review what this extremely broad array of observational and experimental methodologies has taught us about the cultural lives of chimpanzees, gorillas, and orangutans and consider the ways in which this knowledge extends our wider understanding of primate biology and the processes of adaptation and evolution that shape it. I address these issues first by evaluating the extent to which the results of cultural inheritance echo a suite of core principles that underlie organic Darwinian evolution but also extend them in new ways and then by assessing the principal causal interactions between the primary, genetically based organic processes of evolution and the secondary system of cultural inheritance that is based on social learning from others.
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Abstract
A few decades ago, we knew next to nothing about the behavior of our closest animal relative, the chimpanzee, but long-term field studies have since revealed an undreamed-of richness in the diversity of their cultural traditions across Africa. These discoveries have been complemented by a substantial suite of experimental studies, now bridging to the wild through field experiments. These field and experimental studies, particularly those in which direct chimpanzee-child comparisons have been made, delineate a growing set of commonalities between the phenomena of social learning and culture in the lives of chimpanzees and humans. These commonalities in social learning inform our understanding of the evolutionary roots of the cultural propensities the species share. At the same time, such comparisons throw into clearer relief the unique features of the distinctive human capacity for cumulative cultural evolution, and new research has begun to probe the key psychological attributes that may explain it.
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Affiliation(s)
- Andrew Whiten
- Centre for Social Learning and Cognitive Evolution, School of Psychology and Neuroscience, University of St. Andrews, St. Andrews KY16 9JP, United Kingdom;
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24
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A Comparative and Evolutionary Analysis of the Cultural Cognition of Humans and Other Apes. SPANISH JOURNAL OF PSYCHOLOGY 2017; 19:E98. [DOI: 10.1017/sjp.2016.99] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
AbstractThe comparative and evolutionary analysis of social learning and all manner of cultural processes has become a flourishing field. Applying the ‘comparative method’ to such phenomena allows us to exploit the good fortunate we have in being able to study them in satisfying detail in our living primate relatives, using the results to reconstruct the cultural cognition of the ancestral forms we share with these species. Here I offer an overview of principal discoveries in recent years, organized through a developing scheme that targets three main dimensions of culture: the patterning of culturally transmitted traditions in time and space; the underlying social learning processes; and the particular behavioral and psychological contents of cultures. I focus on a comparison between humans, particularly children, and our closest primate relative the chimpanzee, for which we now have much the richest database of relevant observational and experimental findings. Commonalities across these sister-species can be identified in each of the three dimensions listed above and in several subcategories within them, but the comparisons also highlight the major contrasts in the nature of culture that have evolved between ourselves and closest primate relatives.
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25
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Conservatism and "copy-if-better" in chimpanzees (Pan troglodytes). Anim Cogn 2016; 20:575-579. [PMID: 27999955 PMCID: PMC5394136 DOI: 10.1007/s10071-016-1061-7] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2016] [Revised: 10/26/2016] [Accepted: 12/03/2016] [Indexed: 11/30/2022]
Abstract
Social learning is predicted to evolve in socially living animals provided the learning process is not random but biased by certain socio-ecological factors. One bias of particular interest for the emergence of (cumulative) culture is the tendency to forgo personal behaviour in favour of relatively better variants observed in others, also known as the “copy-if-better” strategy. We investigated whether chimpanzees employ copy-if-better in a simple token-exchange paradigm controlling for individual and random social learning. After being trained on one token-type, subjects were confronted with a conspecific demonstrator who either received the same food reward as the subject (control condition) or a higher value food reward than the subject (test condition) for exchanging another token-type. In general, the chimpanzees persisted in exchanging the token-type they were trained on individually, indicating a form of conservatism consistent with previous studies. However, the chimpanzees were more inclined to copy the demonstrator in the test compared to the control condition, indicating a tendency to employ a copy-if-better strategy. We discuss the validity of our results by considering alternative explanations and relate our findings to the emergence of cumulative culture.
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26
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Haun DBM, Tomasello M. How to Compare Across Species. Psychol Sci 2016; 27:1670-1672. [PMID: 27815517 DOI: 10.1177/0956797616671336] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Affiliation(s)
- Daniel B M Haun
- 1 Department for Early Child Development and Culture, Leipzig University.,2 Leipzig Research Center for Early Child Development, Leipzig University
| | - Michael Tomasello
- 3 Department for Developmental and Comparative Psychology, Max Planck Institute for Evolutionary Anthropology, Leipzig, Germany
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27
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Catmur C, Cross ES, Over H. Understanding self and others: from origins to disorders. Philos Trans R Soc Lond B Biol Sci 2016; 371:20150066. [PMID: 26644602 DOI: 10.1098/rstb.2015.0066] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
In order to interpret and engage with the social world, individuals must understand how they relate to others. Self-other understanding forms the backbone of social cognition and is a central concept explored by research into basic processes such as action perception and empathy, as well as research on more sophisticated social behaviours such as cooperation and intergroup interaction. This theme issue integrates the latest research into self-other understanding from evolutionary biology, anthropology, psychology, neuroscience and psychiatry. By gathering perspectives from a diverse range of disciplines, the contributions showcase ways in which research in these areas both informs and is informed by approaches spanning the biological and social sciences, thus deepening our understanding of how we relate to others in a social world.
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Affiliation(s)
| | | | - Harriet Over
- Department of Psychology, University of York, York, UK
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28
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Nielsen M, Haun D. Why developmental psychology is incomplete without comparative and cross-cultural perspectives. Philos Trans R Soc Lond B Biol Sci 2016; 371:20150071. [PMID: 26644590 DOI: 10.1098/rstb.2015.0071] [Citation(s) in RCA: 66] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
As a discipline, developmental psychology has a long history of relying on animal models and data collected among distinct cultural groups to enrich and inform theories of the ways social and cognitive processes unfold through the lifespan. However, approaches that draw together developmental, cross-cultural and comparative perspectives remain rare. The need for such an approach is reflected in the papers by Heyes (2015 Phil. Trans. R. Soc. B 371, 20150069. (doi:10.1098/rstb.2015.0069)), Schmelz & Call (2015 Phil. Trans. R. Soc. B 371, 20150067. (doi:10.1098/rstb.2015.0067)) and Keller (2015 Phil. Trans. R. Soc. B 371, 20150070. (doi:10.1098/rstb.2015.0070)) in this theme issue. Here, we incorporate these papers into a review of recent research endeavours covering a range of core aspects of social cognition, including social learning, cooperation and collaboration, prosociality, and theory of mind. In so doing, we aim to highlight how input from comparative and cross-cultural empiricism has altered our perspectives of human development and, in particular, led to a deeper understanding of the evolution of the human cultural mind.
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Affiliation(s)
- Mark Nielsen
- School of Psychology, University of Queensland, St Lucia, Queensland 4072, Australia Faculty of Humanities, University of Johannesburg, Johannesburg, South Africa
| | - Daniel Haun
- Department of Early Child Development and Culture, University of Leipzig, 04109 Leipzig, Germany
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29
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Städele V, Vigilant L. Strategies for determining kinship in wild populations using genetic data. Ecol Evol 2016; 6:6107-20. [PMID: 27648229 PMCID: PMC5016635 DOI: 10.1002/ece3.2346] [Citation(s) in RCA: 37] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2016] [Revised: 07/01/2016] [Accepted: 07/04/2016] [Indexed: 01/17/2023] Open
Abstract
Knowledge of kin relationships between members of wild animal populations has broad application in ecology and evolution research by allowing the investigation of dispersal dynamics, mating systems, inbreeding avoidance, kin recognition, and kin selection as well as aiding the management of endangered populations. However, the assessment of kinship among members of wild animal populations is difficult in the absence of detailed multigenerational pedigrees. Here, we first review the distinction between genetic relatedness and kinship derived from pedigrees and how this makes the identification of kin using genetic data inherently challenging. We then describe useful approaches to kinship classification, such as parentage analysis and sibship reconstruction, and explain how the combined use of marker systems with biparental and uniparental inheritance, demographic information, likelihood analyses, relatedness coefficients, and estimation of misclassification rates can yield reliable classifications of kinship in groups with complex kin structures. We outline alternative approaches for cases in which explicit knowledge of dyadic kinship is not necessary, but indirect inferences about kinship on a group- or population-wide scale suffice, such as whether more highly related dyads are in closer spatial proximity. Although analysis of highly variable microsatellite loci is still the dominant approach for studies on wild populations, we describe how the long-awaited use of large-scale single-nucleotide polymorphism and sequencing data derived from noninvasive low-quality samples may eventually lead to highly accurate assessments of varying degrees of kinship in wild populations.
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Affiliation(s)
- Veronika Städele
- Department of PrimatologyMax Planck Institute for Evolutionary AnthropologyDeutscher Platz 6D‐04103LeipzigGermany
| | - Linda Vigilant
- Department of PrimatologyMax Planck Institute for Evolutionary AnthropologyDeutscher Platz 6D‐04103LeipzigGermany
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30
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Cronin KA, West V, Ross SR. Investigating the relationship between welfare and rearing young in captive chimpanzees (Pan troglodytes). Appl Anim Behav Sci 2016. [DOI: 10.1016/j.applanim.2016.05.014] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
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31
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McGrew WC. Field studies of Pan troglodytes reviewed and comprehensively mapped, focussing on Japan's contribution to cultural primatology. Primates 2016; 58:237-258. [PMID: 27461577 DOI: 10.1007/s10329-016-0554-y] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2016] [Accepted: 06/24/2016] [Indexed: 10/21/2022]
Abstract
Field studies done over decades of wild chimpanzees in East, Central and West Africa have yielded impressive, cumulative findings in cultural primatology. Japanese primatologists have been involved in this advance from the outset, over a wide variety of topics. Here I review the origins and development of field studies of Pan troglodytes, then assess their progress based on analogy between cultural primatology and cultural anthropology, through four stages: natural history, ethnography, ethnology, and intuition. Then, I focus on six topics that continue to yield informative debate: technology, universals, nuanced variation, archaeology, applied primatology, and ecology. Finally, I offer a map of sites of field study of wild chimpanzees. It is clear that Japanese primatologists have made a significant contribution to East-West scientific exchange, especially at the field sites of Bossou and Mahale.
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Affiliation(s)
- William C McGrew
- Division of Biological Anthropology, Department of Archaeology and Anthropology, University of Cambridge, Fitzwilliam Street, Cambridge, CB2 1QH, UK.
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32
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Briseño-Jaramillo M, Estrada A, Lemasson A. Behavioural innovation and cultural transmission of communication signal in black howler monkeys. Sci Rep 2015; 5:13400. [PMID: 26303965 PMCID: PMC4548217 DOI: 10.1038/srep13400] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2015] [Accepted: 07/24/2015] [Indexed: 11/08/2022] Open
Abstract
Social traditions based on communication signals are widespread in birds, cetaceans and humans, but surprisingly rare in nonhuman primates known for having genetically-determined vocal repertoires. This study presents the first description of a singular case of behaviour associated with calling (placing a hand in front of the mouth while vocalizing: HFM) in black howler monkeys. We showed, first, that HFM was found only in a subset of the groups observed, at the same geographical location, and was age- and sex-specific. There was an audience effect on HFM, with highest rates when a neighbouring group was visible. HFM was non-randomly combined with audio-visual signals and always performed while roaring. High HFM rates triggered more vocal responses from group members and male neighbours, and HFM signalers temporally synchronized their behaviour in a predictable way. Finally, the positioning of the hand systematically modified the call's auditory structure. Altogether these results support the idea that HFM is an innovated, culturally transmitted communication signal that may play a role in inter-group competition and intra-group cohesion. This study opens new lines of research about how nonhuman primates developed strategies to overcome their constraints in acoustic plasticity very early in the primate lineage.
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Affiliation(s)
- M. Briseño-Jaramillo
- Universidad Nacional Autónoma de México. Instituto de Biología, Coyoacán, 04510. México City
| | - A. Estrada
- Universidad Nacional Autónoma de México. Instituto de Biología, Coyoacán, 04510. México City
| | - A. Lemasson
- Université de Rennes 1, Ethologie Animale et Humaine, U.M.R. 6552 - C.N.R.S, Station Biologique, 35380 Paimpont, France
- Institut Universitaire de France, 103 boulevard Saint-Michel 75005 Paris, France
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33
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van Leeuwen EJC, Call J, Haun DBM. Human children rely more on social information than chimpanzees do. Biol Lett 2015; 10:20140487. [PMID: 25392309 DOI: 10.1098/rsbl.2014.0487] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Human societies are characterized by more cultural diversity than chimpanzee communities. However, it is currently unclear what mechanism might be driving this difference. Because reliance on social information is a pivotal characteristic of culture, we investigated individual and social information reliance in children and chimpanzees. We repeatedly presented subjects with a reward-retrieval task on which they had collected conflicting individual and social information of equal accuracy in counterbalanced order. While both species relied mostly on their individual information, children but not chimpanzees searched for the reward at the socially demonstrated location more than at a random location. Moreover, only children used social information adaptively when individual knowledge on the location of the reward had not yet been obtained. Social information usage determines information transmission and in conjunction with mechanisms that create cultural variants, such as innovation, it facilitates diversity. Our results may help explain why humans are more culturally diversified than chimpanzees.
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Affiliation(s)
- Edwin J C van Leeuwen
- Max Planck Institute for Evolutionary Anthropology, Deutscher Platz 6, 04103 Leipzig, Germany Department of Developmental Psychology, University of Jena, Am Steiger 3/1, 07743 Jena, Germany
| | - Josep Call
- Max Planck Institute for Evolutionary Anthropology, Deutscher Platz 6, 04103 Leipzig, Germany School of Psychology and Neuroscience, University of St Andrews, St Mary Quad, South Street, St Andrews KY16 9JP, UK
| | - Daniel B M Haun
- Max Planck Institute for Evolutionary Anthropology, Deutscher Platz 6, 04103 Leipzig, Germany Department of Developmental Psychology, University of Jena, Am Steiger 3/1, 07743 Jena, Germany
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Haun DBM, Rekers Y, Tomasello M. Children conform to the behavior of peers; other great apes stick with what they know. Psychol Sci 2014; 25:2160-7. [PMID: 25355648 DOI: 10.1177/0956797614553235] [Citation(s) in RCA: 46] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
All primates learn things from conspecifics socially, but it is not clear whether they conform to the behavior of these conspecifics--if conformity is defined as overriding individually acquired behavioral tendencies in order to copy peers' behavior. In the current study, chimpanzees, orangutans, and 2-year-old human children individually acquired a problem-solving strategy. They then watched several conspecific peers demonstrate an alternative strategy. The children switched to this new, socially demonstrated strategy in roughly half of all instances, whereas the other two great-ape species almost never adjusted their behavior to the majority's. In a follow-up study, children switched much more when the peer demonstrators were still present than when they were absent, which suggests that their conformity arose at least in part from social motivations. These results demonstrate an important difference between the social learning of humans and great apes, a difference that might help to account for differences in human and nonhuman cultures.
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Affiliation(s)
- Daniel B M Haun
- Max Planck Institute for Evolutionary Anthropology, Leipzig, Germany Max Planck Institute for Psycholinguistics, Nijmegen, The Netherlands Department of Developmental Psychology, University of Jena
| | - Yvonne Rekers
- Max Planck Institute for Evolutionary Anthropology, Leipzig, Germany
| | - Michael Tomasello
- Max Planck Institute for Evolutionary Anthropology, Leipzig, Germany
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Cronin KA, van Leeuwen EJ, Vreeman V, Haun DB. Population-level variability in the social climates of four chimpanzee societies. EVOL HUM BEHAV 2014. [DOI: 10.1016/j.evolhumbehav.2014.05.004] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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van Leeuwen EJC, Cronin KA, Haun DBM. A group-specific arbitrary tradition in chimpanzees (Pan troglodytes). Anim Cogn 2014; 17:1421-5. [PMID: 24916739 DOI: 10.1007/s10071-014-0766-8] [Citation(s) in RCA: 55] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2013] [Revised: 05/08/2014] [Accepted: 05/29/2014] [Indexed: 11/26/2022]
Abstract
Social learning in chimpanzees has been studied extensively and it is now widely accepted that chimpanzees have the capacity to learn from conspecifics through a multitude of mechanisms. Very few studies, however, have documented the existence of spontaneously emerged traditions in chimpanzee communities. While the rigour of experimental studies is helpful to investigate social learning mechanisms, documentation of naturally occurring traditions is necessary to understand the relevance of social learning in the real lives of animals. In this study, we report on chimpanzees spontaneously copying a seemingly non-adaptive behaviour ("grass-in-ear behaviour"). The behaviour entailed chimpanzees selecting a stiff, straw-like blade of grass, inserting the grass into one of their own ears, adjusting the position, and then leaving it in their ear during subsequent activities. Using a daily focal follow procedure, over the course of 1 year, we observed 8 (out of 12) group members engaging in this peculiar behaviour. Importantly, in the three neighbouring groups of chimpanzees (n = 82), this behaviour was only observed once, indicating that ecological factors were not determiners of the prevalence of this behaviour. These observations show that chimpanzees have a tendency to copy each other's behaviour, even when the adaptive value of the behaviour is presumably absent.
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Affiliation(s)
- Edwin J C van Leeuwen
- Max Planck Institute for Psycholinguistics, Max Planck Institute for Evolutionary Anthropology, PO Box 310, 6500 AH, Nijmegen, The Netherlands,
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Problem solving in the presence of others: how rank and relationship quality impact resource acquisition in chimpanzees (Pan troglodytes). PLoS One 2014; 9:e93204. [PMID: 24695486 PMCID: PMC3973697 DOI: 10.1371/journal.pone.0093204] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2013] [Accepted: 02/28/2014] [Indexed: 11/19/2022] Open
Abstract
In the wild, chimpanzees (Pan troglodytes) are often faced with clumped food resources that they may know how to access but abstain from doing so due to social pressures. To better understand how social settings influence resource acquisition, we tested fifteen semi-wild chimpanzees from two social groups alone and in the presence of others. We investigated how resource acquisition was affected by relative social dominance, whether collaborative problem solving or (active or passive) sharing occurred amongst any of the dyads, and whether these outcomes were related to relationship quality as determined from six months of observational data. Results indicated that chimpanzees obtained fewer rewards when tested in the presence of others compared to when they were tested alone, and this loss tended to be greater when paired with a higher ranked individual. Individuals demonstrated behavioral inhibition; chimpanzees who showed proficient skill when alone often abstained from solving the task when in the presence of others. Finally, individuals with close social relationships spent more time together in the problem solving space, but collaboration and sharing were infrequent and sessions in which collaboration or sharing did occur contained more instances of aggression. Group living provides benefits and imposes costs, and these findings highlight that one cost of group living may be diminishing productive individual behaviors.
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Van Leeuwen EJC, Cronin KA, Schütte S, Call J, Haun DBM. Chimpanzees (Pan troglodytes) flexibly adjust their behaviour in order to maximize payoffs, not to conform to majorities. PLoS One 2013; 8:e80945. [PMID: 24312252 PMCID: PMC3842352 DOI: 10.1371/journal.pone.0080945] [Citation(s) in RCA: 53] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2013] [Accepted: 10/15/2013] [Indexed: 11/19/2022] Open
Abstract
Chimpanzees have been shown to be adept learners, both individually and socially. Yet, sometimes their conservative nature seems to hamper the flexible adoption of superior alternatives, even to the extent that they persist in using entirely ineffective strategies. In this study, we investigated chimpanzees’ behavioural flexibility in two different conditions under which social animals have been predicted to abandon personal preferences and adopt alternative strategies: i) under influence of majority demonstrations (i.e. conformity), and ii) in the presence of superior reward contingencies (i.e. maximizing payoffs). Unlike previous nonhuman primate studies, this study disentangled the concept of conformity from the tendency to maintain one’s first-learned strategy. Studying captive (n=16) and semi-wild (n=12) chimpanzees in two complementary exchange paradigms, we found that chimpanzees did not abandon their behaviour in order to match the majority, but instead remained faithful to their first-learned strategy (Study 1a and 1b). However, the chimpanzees’ fidelity to their first-learned strategy was overridden by an experimental upgrade of the profitability of the alternative strategy (Study 2). We interpret our observations in terms of chimpanzees’ relative weighing of behavioural options as a function of situation-specific trade-offs. More specifically, contrary to previous findings, chimpanzees in our study abandoned their familiar behaviour to maximize payoffs, but not to conform to a majority.
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Affiliation(s)
- Edwin J. C. Van Leeuwen
- Max Planck Research Group for Comparative Cognitive Anthropology, Max Planck Institute for Psycholinguistics, Nijmegen, The Netherlands
- * E-mail:
| | - Katherine A. Cronin
- Max Planck Research Group for Comparative Cognitive Anthropology, Max Planck Institute for Psycholinguistics, Nijmegen, The Netherlands
| | - Sebastian Schütte
- Max Planck Institute for Evolutionary Anthropology, Leipzig, Germany
| | - Josep Call
- Max Planck Institute for Evolutionary Anthropology, Leipzig, Germany
| | - Daniel B. M. Haun
- Max Planck Research Group for Comparative Cognitive Anthropology, Max Planck Institute for Evolutionary Anthropology, Leipzig, Germany
- Max Planck Institute for Psycholinguistics, Nijmegen, The Netherlands
- University of Portsmouth, Portsmouth, United Kingdom
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Luef EM, Pika S. Gorilla mothers also matter! New insights on social transmission in gorillas (Gorilla gorilla gorilla) in captivity. PLoS One 2013; 8:e79600. [PMID: 24312184 PMCID: PMC3842280 DOI: 10.1371/journal.pone.0079600] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2013] [Accepted: 09/24/2013] [Indexed: 11/19/2022] Open
Abstract
The present paper describes two distinct behaviors relating to food processing and communication that were observed in a community of five separately housed groups of lowland gorillas (Gorilla gorilla gorilla) in captivity during two study periods one decade apart: (1) a food processing technique to separate wheat from chaff, the so-called puff-blowing technique; and (2) a male display used to attract the attention of visitors, the so-called throw-kiss-display. We investigated (a) whether the behaviors were transmitted within the respective groups; and if yes, (b) their possible mode of transmission. Our results showed that only the food processing technique spread from three to twenty-one individuals during the ten-year period, whereas the communicative display died out completely. The main transmission mode of the puff-blowing technique was the mother-offspring dyad: offspring of puff-blowing mothers showed the behavior, while the offspring of non- puff-blowing mothers did not. These results strongly support the role mothers play in the acquisition of novel skills and vertical social transmission. Furthermore, they suggest that behaviors, which provide a direct benefit to individuals, have a high chance of social transmission while the loss of benefits can result in the extinction of behaviors.
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Affiliation(s)
- Eva Maria Luef
- Max Planck Institute for Ornithology, Humboldt Research Group “Comparative Gestural Signalling,” Seewiesen, Germany
| | - Simone Pika
- Max Planck Institute for Ornithology, Humboldt Research Group “Comparative Gestural Signalling,” Seewiesen, Germany
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Early social deprivation negatively affects social skill acquisition in chimpanzees (Pan troglodytes). Anim Cogn 2013; 17:407-14. [PMID: 23954954 DOI: 10.1007/s10071-013-0672-5] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2013] [Revised: 08/01/2013] [Accepted: 08/07/2013] [Indexed: 02/03/2023]
Abstract
In a highly social species like chimpanzees, the process by which individuals become attuned to their social environment may be of vital importance to their chances of survival. Typically, this socialization process, defined by all acquisition experiences and fine-tuning efforts of social interaction patterns during ontogeny, occurs in large part through parental investment. In this study, we investigated whether maternal presence enhances the socialization process in chimpanzees by comparing the social interactions of orphaned and mother-reared individuals at the Chimfunshi Wildlife Orphanage Trust in Zambia. As response variables, we selected social interactions during which an elaborate level of fine-tuning is assumed to be necessary for sustaining the interaction and preventing escalation: social play. Comparing orphaned (n = 8) to sex- and age-matched mother-reared juvenile chimpanzees (n = 9), we hypothesized that the orphaned juveniles would play less frequently than the mother-reared and would be less equipped for fine-tuning social play (which we assayed by rates of aggression) because of the lack of a safe and facilitating social environment provided by the mother. First, contrary to our hypothesis, results showed that the orphaned juveniles engaged in social play more frequently than the mother-reared juveniles, although for significantly shorter amounts of time. Second, in support of our hypothesis, results showed that social play of the orphaned juveniles more often resulted in aggression than social play of the mother-reared juveniles. In conjunction, these results may indicate that, just like in humans, chimpanzee mothers provide their offspring with adequate social skills that might be of pivotal importance for future challenges like successful group-living and securing competitive fitness advantages.
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Nakamura M, Nishida T. Ontogeny of a social custom in wild chimpanzees: age changes in grooming hand-clasp at Mahale. Am J Primatol 2012. [PMID: 23184762 DOI: 10.1002/ajp.22098] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Among cultural behaviors of chimpanzees, the developmental processes of complex skills involved in tool use are relatively well known. However, few studies have examined the ontogeny of social customs that do not require complex skills. Thus, in this study, we describe the developmental process of the grooming hand-clasp (GHC), one of the well-known social customs of chimpanzees at Mahale. We have collected 383 cases of GHC where at least one of the participants was 15 years old or younger during 1994-2007. First performances of GHC with the mother were observed at around 4-6 years old; the earliest observed age was 4 years and 4 months old. The first performances of GHC with nonrelated females were at around age 9 years, and those with adult males at around 11 years. However, some orphans engaged in GHC earlier than nonorphans. By gradually expanding GHC partners from the mother to other females and then to males, chimpanzees increased the number of GHC partners with age. Young males were observed to perform GHC with larger numbers of partners than were young females. GHC by young chimpanzees was shorter in duration than that among adults. Overall, the ontogeny of GHC showed several dissimilarities with that of tool use and was more an extension of the development of typical grooming behavior. For example, infants did not try to perform GHC initially; instead, mothers were more active in the earliest stages. These results suggest that not all socially learned cultural behaviors are acquired in the way of learning tool use. There may be various ways of learning behavioral patterns that are performed continuously in a group and that consequently comprise culture in chimpanzees.
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