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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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Nöbel S, Jacquet A, Isabel G, Pocheville A, Seabright P, Danchin E. Conformity in mate choice, the overlooked social component of animal and human culture. Biol Rev Camb Philos Soc 2023; 98:132-149. [PMID: 36173001 PMCID: PMC10087591 DOI: 10.1111/brv.12899] [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: 11/23/2021] [Revised: 08/16/2022] [Accepted: 08/19/2022] [Indexed: 01/12/2023]
Abstract
Although conformity as a major driver for human cultural evolution is a well-accepted and intensely studied phenomenon, its importance for non-human animal culture has been largely overlooked until recently. This limited for decades the possibility of studying the roots of human culture. Here, we provide a historical review of the study of conformity in both humans and non-human animals. We identify gaps in knowledge and propose an evolutionary route towards the sophisticated cultural processes that characterize humanity. A landmark in the study of conformity is Solomon Asch's famous experiment on humans in 1955. By contrast, interest in conformity among evolutionary biologists has only become salient since the turn of the new millennium. A striking result of our review is that, although studies of conformity have examined many biological contexts, only one looked at mate choice. This is surprising because mate choice is probably the only context in which conformity has self-reinforcing advantages across generations. Within a metapopulation, i.e. a group of subpopulations connected by dispersing individuals, dispersers able to conform to the local preference for a given type of mate have a strong and multigenerational fitness advantage. This is because once females within one subpopulation locally show a bias for one type of males, immigrant females who do not conform to the local trend have sons, grandsons, etc. of the non-preferred phenotype, which negatively and cumulatively affects fitness over generations in a process reminiscent of the Fisher runaway process. This led us to suggest a sex-driven origin of conformity, indicating a possible evolutionary route towards animal and human culture that is rooted in the basic, and thus ancient, social constraints acting on mating preferences within a metapopulation. In a generic model, we show that dispersal among subpopulations within a metapopulation can effectively maintain independent Fisher runaway processes within subpopulations, while favouring the evolution of social learning and conformity at the metapopulation scale; both being essential for the evolution of long-lasting local traditions. The proposed evolutionary route to social learning and conformity casts surprising light on one of the major processes that much later participated in making us human. We further highlight several research avenues to define the spectrum of conformity better, and to account for its complexity. Future studies of conformity should incorporate experimental manipulation of group majority. We also encourage the study of potential links between conformity and mate copying, animal aggregations, and collective actions. Moreover, validation of the sex-driven origin of conformity will rest on the capacity of human and evolutionary sciences to investigate jointly the origin of social learning and conformity. This constitutes a stimulating common agenda and militates for a rapprochement between these two currently largely independent research areas.
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Affiliation(s)
- Sabine Nöbel
- Institute for Advanced Study in Toulouse (IAST), Université Toulouse 1 Capitole, Toulouse, France.,Laboratoire Évolution et Diversité Biologique (EDB UMR 5174), Université de Toulouse, CNRS, IRD, 118 route de Narbonne, F-31062, Toulouse cedex 9, France
| | - Antoine Jacquet
- Institute for Advanced Study in Toulouse (IAST), Université Toulouse 1 Capitole, Toulouse, France.,Toulouse School of Economics (TSE), Université Toulouse 1 Capitole, Toulouse, France
| | - Guillaume Isabel
- Centre de Recherches sur la Cognition Animale, Centre de Biologie Intégrative, Université de Toulouse, CNRS, UPS, 118 route de Narbonne, F-31062, Toulouse cedex 9, France
| | - Arnaud Pocheville
- Laboratoire Évolution et Diversité Biologique (EDB UMR 5174), Université de Toulouse, CNRS, IRD, 118 route de Narbonne, F-31062, Toulouse cedex 9, France
| | - Paul Seabright
- Institute for Advanced Study in Toulouse (IAST), Université Toulouse 1 Capitole, Toulouse, France.,Toulouse School of Economics (TSE), Université Toulouse 1 Capitole, Toulouse, France
| | - Etienne Danchin
- Laboratoire Évolution et Diversité Biologique (EDB UMR 5174), Université de Toulouse, CNRS, IRD, 118 route de Narbonne, F-31062, Toulouse cedex 9, France
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3
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Watson SK, Filippi P, Gasparri L, Falk N, Tamer N, Widmer P, Manser M, Glock H. Optionality in animal communication: a novel framework for examining the evolution of arbitrariness. Biol Rev Camb Philos Soc 2022; 97:2057-2075. [PMID: 35818133 PMCID: PMC9795909 DOI: 10.1111/brv.12882] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2021] [Revised: 06/14/2022] [Accepted: 06/16/2022] [Indexed: 12/30/2022]
Abstract
A critical feature of language is that the form of words need not bear any perceptual similarity to their function - these relationships can be 'arbitrary'. The capacity to process these arbitrary form-function associations facilitates the enormous expressive power of language. However, the evolutionary roots of our capacity for arbitrariness, i.e. the extent to which related abilities may be shared with animals, is largely unexamined. We argue this is due to the challenges of applying such an intrinsically linguistic concept to animal communication, and address this by proposing a novel conceptual framework highlighting a key underpinning of linguistic arbitrariness, which is nevertheless applicable to non-human species. Specifically, we focus on the capacity to associate alternative functions with a signal, or alternative signals with a function, a feature we refer to as optionality. We apply this framework to a broad survey of findings from animal communication studies and identify five key dimensions of communicative optionality: signal production, signal adjustment, signal usage, signal combinatoriality and signal perception. We find that optionality is widespread in non-human animals across each of these dimensions, although only humans demonstrate it in all five. Finally, we discuss the relevance of optionality to behavioural and cognitive domains outside of communication. This investigation provides a powerful new conceptual framework for the cross-species investigation of the origins of arbitrariness, and promises to generate original insights into animal communication and language evolution more generally.
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Affiliation(s)
- Stuart K. Watson
- Department of Comparative Language ScienceUniversity of ZurichAffolternstrasse 568050ZürichSwitzerland,Center for the Interdisciplinary Study of Language EvolutionUniversity of ZurichAffolternstrasse 568050ZürichSwitzerland,Department of Evolutionary Biology and Environmental StudiesUniversity of ZurichWinterthurerstrasse 1908057ZurichSwitzerland
| | - Piera Filippi
- Department of Comparative Language ScienceUniversity of ZurichAffolternstrasse 568050ZürichSwitzerland,Center for the Interdisciplinary Study of Language EvolutionUniversity of ZurichAffolternstrasse 568050ZürichSwitzerland,Department of PhilosophyUniversity of ZurichZurichbergstrasse 438044ZürichSwitzerland
| | - Luca Gasparri
- Department of PhilosophyUniversity of ZurichZurichbergstrasse 438044ZürichSwitzerland,Univ. Lille, CNRS, UMR 8163 – STL – Savoirs Textes LangageF‐59000LilleFrance
| | - Nikola Falk
- Center for the Interdisciplinary Study of Language EvolutionUniversity of ZurichAffolternstrasse 568050ZürichSwitzerland,Department of Evolutionary Biology and Environmental StudiesUniversity of ZurichWinterthurerstrasse 1908057ZurichSwitzerland
| | - Nicole Tamer
- Department of Comparative Language ScienceUniversity of ZurichAffolternstrasse 568050ZürichSwitzerland,Center for the Interdisciplinary Study of Language EvolutionUniversity of ZurichAffolternstrasse 568050ZürichSwitzerland
| | - Paul Widmer
- Department of Comparative Language ScienceUniversity of ZurichAffolternstrasse 568050ZürichSwitzerland,Center for the Interdisciplinary Study of Language EvolutionUniversity of ZurichAffolternstrasse 568050ZürichSwitzerland
| | - Marta Manser
- Center for the Interdisciplinary Study of Language EvolutionUniversity of ZurichAffolternstrasse 568050ZürichSwitzerland,Department of Evolutionary Biology and Environmental StudiesUniversity of ZurichWinterthurerstrasse 1908057ZurichSwitzerland
| | - Hans‐Johann Glock
- Center for the Interdisciplinary Study of Language EvolutionUniversity of ZurichAffolternstrasse 568050ZürichSwitzerland,Department of PhilosophyUniversity of ZurichZurichbergstrasse 438044ZürichSwitzerland
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Watson SK, Lambeth SP, Schapiro SJ. Innovative multi-material tool use in the pant-hoot display of a chimpanzee. Sci Rep 2022; 12:20605. [PMID: 36446876 PMCID: PMC9708694 DOI: 10.1038/s41598-022-24770-w] [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: 09/29/2022] [Accepted: 11/21/2022] [Indexed: 11/30/2022] Open
Abstract
'Pant-hoot displays' are a species-typical, multi-modal communicative behaviour in chimpanzees in which pant-hoot vocalisations are combined with varied behavioural displays. In both captivity and the wild, individuals commonly incorporate striking or throwing elements of their environment into these displays. In this case study, we present five videos of an unenculturated, captive, adult male chimpanzee combining a large rubber feeding tub with excelsior (wood wool) in a multi-step process, which was then integrated into the subject's pant-hoot displays as a percussive tool or 'instrument'. During the construction process, the subject demonstrated an understanding of the relevant properties of these materials, 'repairing' the tub to be a more functional drum when necessary. We supplement these videos with a survey of care staff from the study site for additional detail and context. Although care must be taken in generalising data from a single individual, the behaviour reported here hints at three intriguing features of chimpanzee communicative cognition: (1) it suggests a degree of voluntary control over vocal production, (2) it is a so-far unique example of compound tool innovation and use in communicative behaviour and (3) it may represent an example of forward planning in communicative behaviour. Each of these would represent hitherto undocumented dimensions of flexibility in chimpanzee communication, mapping fertile ground for future research.
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Affiliation(s)
- Stuart K. Watson
- grid.7400.30000 0004 1937 0650Department of Comparative Language Science, University of Zurich, Affolternstrasse 56, 8050 Zürich, Switzerland ,grid.7400.30000 0004 1937 0650Center for the Interdisciplinary Study of Language Evolution, University of Zurich, Affolternstrasse 56, 8050 Zürich, Switzerland ,grid.7400.30000 0004 1937 0650Department of Evolutionary Biology and Environmental Studies, University of Zurich, Winterthurerstrasse 190, 8057 Zurich, Switzerland
| | - Susan P. Lambeth
- grid.240145.60000 0001 2291 4776Department of Comparative Medicine, The University of Texas MD Anderson Cancer Center, 650 Cool Water Drive, Bastrop, TX 78602 USA
| | - Steven J. Schapiro
- grid.240145.60000 0001 2291 4776Department of Comparative Medicine, The University of Texas MD Anderson Cancer Center, 650 Cool Water Drive, Bastrop, TX 78602 USA ,grid.5254.60000 0001 0674 042XDepartment of Experimental Medicine, University of Copenhagen, Copenhagen, Denmark
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Whiten A, Harrison RA, McGuigan N, Vale GL, Watson SK. Collective knowledge and the dynamics of culture in chimpanzees. Philos Trans R Soc Lond B Biol Sci 2022; 377:20200321. [PMID: 34894742 PMCID: PMC8666901 DOI: 10.1098/rstb.2020.0321] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2021] [Accepted: 07/13/2021] [Indexed: 12/16/2022] Open
Abstract
Social learning in non-human primates has been studied experimentally for over 120 years, yet until the present century this was limited to what one individual learns from a single other. Evidence of group-wide traditions in the wild then highlighted the collective context for social learning, and broader 'diffusion experiments' have since demonstrated transmission at the community level. In the present article, we describe and set in comparative perspective three strands of our recent research that further explore the collective dimensions of culture and cumulative culture in chimpanzees. First, exposing small communities of chimpanzees to contexts incorporating increasingly challenging, but more rewarding tool use opportunities revealed solutions arising through the combination of different individuals' discoveries, spreading to become shared innovations. The second series of experiments yielded evidence of conformist changes from habitual techniques to alternatives displayed by a unanimous majority of others but implicating a form of quorum decision-making. Third, we found that between-group differences in social tolerance were associated with differential success in developing more complex tool use to exploit an increasingly inaccessible resource. We discuss the implications of this array of findings in the wider context of related studies of humans, other primates and non-primate species. 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)
- Andrew Whiten
- Centre for Social Learning and Cognitive Evolution, and Scottish Primate Research Group, School of Psychology and Neuroscience, University of St Andrews, South Street, St Andrews KY16 9JP, UK
| | - Rachel A. Harrison
- Centre for Social Learning and Cognitive Evolution, and Scottish Primate Research Group, School of Psychology and Neuroscience, University of St Andrews, South Street, St Andrews KY16 9JP, UK
- Department of Ecology and Evolution, University of Lausanne, Lausanne 1015, Switzerland
| | - Nicola McGuigan
- Centre for Social Learning and Cognitive Evolution, and Scottish Primate Research Group, School of Psychology and Neuroscience, University of St Andrews, South Street, St Andrews KY16 9JP, UK
- School of Education and Social Sciences, University of the West of Scotland, Paisley PA1 2BE, UK
| | - Gillian L. Vale
- Centre for Social Learning and Cognitive Evolution, and Scottish Primate Research Group, School of Psychology and Neuroscience, University of St Andrews, South Street, St Andrews KY16 9JP, UK
- Lester E Fisher Center for the Study and Conservation of Apes, Lincoln Park Zoo, Chicago, IL, USA
| | - Stuart K. Watson
- Centre for Social Learning and Cognitive Evolution, and Scottish Primate Research Group, School of Psychology and Neuroscience, University of St Andrews, South Street, St Andrews KY16 9JP, UK
- Department of Evolutionary Biology and Environmental Studies, University of Zurich, Zurich, Switzerland
- Department of Comparative Language Science, University of Zurich, Zurich, Switzerland
- Center for the Interdisciplinary Study of Language Evolution, University of Zurich, Zurich, Switzerland
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Conformity versus transmission in animal cultures. Behav Brain Sci 2022; 45:e273. [DOI: 10.1017/s0140525x22001182] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
Abstract
The principal contrasts that Jagiello et al. highlight are among many cultural transmission biases we now know of. I suggest they are also reflected more widely in social learning decisions among nonhuman animal cultures governing whether cultural innovations spread, or are instead over-ridden by immigrants' conformity in their new group. Such conformity may serve either informational or social-integrative functions.
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Vale GL, McGuigan N, Burdett E, Lambeth SP, Lucas A, Rawlings B, Schapiro SJ, Watson SK, Whiten A. Why do chimpanzees have diverse behavioral repertoires yet lack more complex cultures? Invention and social information use in a cumulative task. EVOL HUM BEHAV 2021. [DOI: 10.1016/j.evolhumbehav.2020.11.003] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
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Chimpanzees' behavioral flexibility, social tolerance, and use of tool-composites in a progressively challenging foraging problem. iScience 2021; 24:102033. [PMID: 33521600 PMCID: PMC7820130 DOI: 10.1016/j.isci.2021.102033] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2020] [Revised: 09/01/2020] [Accepted: 12/31/2020] [Indexed: 11/23/2022] Open
Abstract
Behavioral flexibility is a critical ability allowing animals to respond to changes in their environment. Previous studies have found evidence of inflexibility when captive chimpanzees are faced with changing task parameters. We provided two groups of sanctuary-housed chimpanzees with a foraging task in which solutions were restricted over time. Initially, juice could be retrieved from within a tube by hand or by using tool materials, but effective solutions were then restricted by narrowing the tube, necessitating the abandonment of previous solutions and adoption of new ones. Chimpanzees responded flexibly, but one group increased their use of effective techniques to a greater extent than the other. Tool-composite techniques emerged in both groups, but primarily in the more flexible group. The more flexible group also showed higher rates of socio-positive behaviors at the task. In conjunction, these findings support the hypothesis that social tolerance may facilitate the emergence and spread of novel behaviors. Chimpanzees adapted their tool use to a change in foraging constraints Groups differed significantly in the level of behavioral flexibility observed The more flexible group showed higher rates of socio-positive behaviors at the task Tool-composite techniques were observed, primarily in the more flexible group
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The Relationship Between Tool Use and Prey Availability in Chimpanzees (Pan troglodytes schweinfurthii) of Northern Democratic Republic of Congo. INT J PRIMATOL 2020. [DOI: 10.1007/s10764-020-00149-4] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
AbstractA key feature of human behavioral diversity is that it can be constrained by cultural preference (“cultural override”); that is, population-specific preferences can override resource availability. Here we investigate whether a similar phenomenon can be found in one of our closest relatives, as well as the potential impacts of ecological differences on feeding behavior. Our study subjects were different subpopulations of Eastern chimpanzees (Pan troglodytes schweinfurthii) occupying two very different habitats, moist tropical lowland forests vs. moist tropical forest–savanna mosaic on opposite sides of a major river. Given differences in encounter rates of different kinds of tool sites on both sides of the Uele River, we predicted that these subpopulations would differ in their likelihood of using tools to prey on two insect species despite similar availability. In surveys conducted over a 9-year period at 19 different survey regions in northern Democratic Republic of Congo (10 in lowland forest and 9 in mosaic), we collected and analyzed data on chimpanzee tool-assisted exploitation of insects. To determine the availability of insect species eaten by the chimpanzees, we counted insects and their mounds on transects and recces at 12 of these sites. For stick tools used to harvest epigaeic Dorylus and ponerine ants, we evaluated seasonal, geographical, and prey-availability factors that might influence their occurrence, using nest encounter rate as a proxy to control for chimpanzee abundance. Across the 19 survey regions spanning both sides of the Uele, we found little difference in the availability of epigaeic Dorylus and ponerine ants. Despite this, tool encounter rates for epigaeic Dorylus, but not ponerine, ants were significantly higher in the mosaic to the north of the Uele. Furthermore, we found no evidence for termite fishing anywhere, despite the availability of Macrotermes mounds throughout the region and the fact that chimpanzees at a number of other study sites use tools to harvest these termites. Instead, the chimpanzees of this region used a novel percussive technique to harvest two other types of termites, Cubitermes sp. and Thoracotermes macrothorax. This mismatch between prey availability and predation is consistent with cultural override, but given the different habitats on the two sides of the Uele River, we cannot fully rule out the influence of ecological factors. Comparing our findings with those of similar studies of other chimpanzee populations promises to contribute to our understanding of the evolution of behavioral diversity in humans and our closest cousins.
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A unified account of culture should accommodate animal cultures. Behav Brain Sci 2020; 43:e118. [DOI: 10.1017/s0140525x1900270x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
Abstract
Discoveries about social learning and culture in non-human animals have burgeoned this century, yet despite aspiring to offer a unified account of culture, the target article neglects these discoveries almost totally. I offer an overview of principal findings in this field including phylogenetic reach, intraspecies pervasiveness, stability, fidelity, and attentional funnelling in social learning. Can the authors’ approach accommodate these?
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11
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Whiten A. Conformity and over-imitation: An integrative review of variant forms of hyper-reliance on social learning. ADVANCES IN THE STUDY OF BEHAVIOR 2019. [DOI: 10.1016/bs.asb.2018.12.003] [Citation(s) in RCA: 23] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
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Watson SK, Vale GL, Hopper LM, Dean LG, Kendal RL, Price EE, Wood LA, Davis SJ, Schapiro SJ, Lambeth SP, Whiten A. Chimpanzees demonstrate individual differences in social information use. Anim Cogn 2018; 21:639-650. [PMID: 29922865 PMCID: PMC6097074 DOI: 10.1007/s10071-018-1198-7] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2017] [Revised: 05/30/2018] [Accepted: 06/13/2018] [Indexed: 02/07/2023]
Abstract
Studies of transmission biases in social learning have greatly informed our understanding of how behaviour patterns may diffuse through animal populations, yet within-species inter-individual variation in social information use has received little attention and remains poorly understood. We have addressed this question by examining individual performances across multiple experiments with the same population of primates. We compiled a dataset spanning 16 social learning studies (26 experimental conditions) carried out at the same study site over a 12-year period, incorporating a total of 167 chimpanzees. We applied a binary scoring system to code each participant's performance in each study according to whether they demonstrated evidence of using social information from conspecifics to solve the experimental task or not (Social Information Score-'SIS'). Bayesian binomial mixed effects models were then used to estimate the extent to which individual differences influenced SIS, together with any effects of sex, rearing history, age, prior involvement in research and task type on SIS. An estimate of repeatability found that approximately half of the variance in SIS was accounted for by individual identity, indicating that individual differences play a critical role in the social learning behaviour of chimpanzees. According to the model that best fit the data, females were, depending on their rearing history, 15-24% more likely to use social information to solve experimental tasks than males. However, there was no strong evidence of an effect of age or research experience, and pedigree records indicated that SIS was not a strongly heritable trait. Our study offers a novel, transferable method for the study of individual differences in social learning.
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Affiliation(s)
- Stuart K Watson
- Centre for Social Learning and Cognitive Evolution, and Scottish Primate Research Group, School of Psychology and Neuroscience, University of St Andrews, St Andrews, UK
| | - Gillian L Vale
- Centre for Social Learning and Cognitive Evolution, and Scottish Primate Research Group, School of Psychology and Neuroscience, University of St Andrews, St Andrews, UK.,Department of Veterinary Sciences, National Center for Chimpanzee Care, Michale E. Keeling Center for Comparative Medicine and Research, UT MD Anderson Cancer Center, Bastrop, TX, USA
| | - Lydia M Hopper
- Lester E. Fisher Center for the Study and Conservation of Apes, Lincoln Park Zoo, Chicago, IL, 60614, USA
| | - Lewis G Dean
- Centre for Social Learning and Cognitive Evolution, and Scottish Primate Research Group, School of Psychology and Neuroscience, University of St Andrews, St Andrews, UK
| | - Rachel L Kendal
- Department of Anthropology, Centre for the Coevolution of Biology and Culture, Durham University, Durham, UK
| | - Elizabeth E Price
- Centre for Behaviour and Evolution, Institute of Neuroscience, Newcastle University, Newcastle upon Tyne, UK
| | - Lara A Wood
- Centre for Social Learning and Cognitive Evolution, and Scottish Primate Research Group, School of Psychology and Neuroscience, University of St Andrews, St Andrews, UK.,Division of Psychology, Abertay University, Bell Street, Dundee, UK
| | - Sarah J Davis
- Centre for Social Learning and Cognitive Evolution, and Scottish Primate Research Group, School of Psychology and Neuroscience, University of St Andrews, St Andrews, UK
| | - Steven J Schapiro
- Department of Veterinary Sciences, National Center for Chimpanzee Care, Michale E. Keeling Center for Comparative Medicine and Research, UT MD Anderson Cancer Center, Bastrop, TX, USA.,Department of Experimental Medicine, University of Copenhagen, Copenhagen, Denmark
| | - Susan P Lambeth
- Department of Veterinary Sciences, National Center for Chimpanzee Care, Michale E. Keeling Center for Comparative Medicine and Research, UT MD Anderson Cancer Center, Bastrop, TX, USA
| | - Andrew Whiten
- Centre for Social Learning and Cognitive Evolution, and Scottish Primate Research Group, School of Psychology and Neuroscience, University of St Andrews, St Andrews, UK.
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