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Westra E, Fitzpatrick S, Brosnan SF, Gruber T, Hobaiter C, Hopper LM, Kelly D, Krupenye C, Luncz LV, Theriault J, Andrews K. In search of animal normativity: a framework for studying social norms in non-human animals. Biol Rev Camb Philos Soc 2024; 99:1058-1074. [PMID: 38268182 PMCID: PMC11078603 DOI: 10.1111/brv.13056] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2023] [Revised: 01/13/2024] [Accepted: 01/16/2024] [Indexed: 01/26/2024]
Abstract
Social norms - rules governing which behaviours are deemed appropriate or inappropriate within a given community - are typically taken to be uniquely human. Recently, this position has been challenged by a number of philosophers, cognitive scientists, and ethologists, who have suggested that social norms may also be found in certain non-human animal communities. Such claims have elicited considerable scepticism from norm cognition researchers, who doubt that any non-human animals possess the psychological capacities necessary for normative cognition. However, there is little agreement among these researchers about what these psychological prerequisites are. This makes empirical study of animal social norms difficult, since it is not clear what we are looking for and thus what should count as behavioural evidence for the presence (or absence) of social norms in animals. To break this impasse, we offer an approach that moves beyond contested psychological criteria for social norms. This approach is inspired by the animal culture research program, which has made a similar shift away from heavily psychological definitions of 'culture' to become organised around a cluster of more empirically tractable concepts of culture. Here, we propose an analogous set of constructs built around the core notion of a normative regularity, which we define as a socially maintained pattern of behavioural conformity within a community. We suggest methods for studying potential normative regularities in wild and captive primates. We also discuss the broader scientific and philosophical implications of this research program with respect to questions of human uniqueness, animal welfare and conservation.
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Affiliation(s)
- Evan Westra
- Department of Philosophy, Purdue University, 100 N. University Street, West Lafayette, IN, 47905, USA
| | - Simon Fitzpatrick
- Department of Philosophy, John Carroll University, 1 John Carroll Boulevard, University Heights, Ohio 44118, USA
| | - Sarah F. Brosnan
- Departments of Psychology & Philosophy, Neuroscience Institute, Center for Behavioral Neuroscience, and the Language Research Center, Georgia State University, Georgia State University, Dept of Psychology, PO Box 5010, Atlanta, GA 30302-5010 USA
| | - Thibaud Gruber
- Faculty of Psychology and Educational Sciences, and Swiss Center for Affective Sciences, Campus Biotech - University of Geneva, Chemin des Mines 9, 1202 Geneva, Switzerland
| | - Catherine Hobaiter
- School of Psychology and Neuroscience, University of St Andrews, St Mary’s Quad, South St, Fife KY16 9JP, Scotland
| | - Lydia M. Hopper
- Department of Molecular and Comparative Pathobiology, Johns Hopkins University School of Medicine, 720 Rutland Ave, Baltimore, Maryland, 21205, USA
| | - Daniel Kelly
- Department of Philosophy, Purdue University, 100 N. University Street, West Lafayette, IN, 47905, USA
| | - Christopher Krupenye
- Department of Psychological & Brain Sciences, Johns Hopkins University, 3400 N. Charles St, Baltimore, MD 21218, USA
| | - Lydia V. Luncz
- Technological Primates Research Group, Max Planck Institute for Evolutionary Anthropology, Deutscher Platz 6, 04103 Leipzig, Germany
| | - Jordan Theriault
- Department of Radiology, Athinoula A. Martinos Center for Biomedical Imaging, Massachusetts General Hospital and Harvard Medical School, Suite 2301, 149 Thirteenth Street, Charlestown, MA 02129, USA
| | - Kristin Andrews
- Department of Philosophy, York University, S448 Ross Building, 4700 Keele Street, Toronto, ON M3J 1P3, Canada
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Chimento M, Aplin LM. Understanding the Role of Naive Learners in Cultural Change. Am Nat 2024; 203:695-712. [PMID: 38781528 DOI: 10.1086/730110] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/25/2024]
Abstract
AbstractA change to a population's social network is a change to the substrate of cultural transmission, affecting behavioral diversity and adaptive cultural evolution. While features of network structure such as population size and density have been well studied, less is understood about the influence of social processes such as population turnover-or the repeated replacement of individuals by naive individuals. Experimental data have led to the hypothesis that naive learners can drive cultural evolution by better assessing the relative value of behaviors, although this hypothesis has been expressed only verbally. We conducted a formal exploration of this hypothesis using a generative model that concurrently simulated its two key ingredients: social transmission and reinforcement learning. We simulated competition between high- and low-reward behaviors while varying turnover magnitude and tempo. Variation in turnover influenced changes in the distributions of cultural behaviors, irrespective of initial knowledge-state conditions. We found optimal turnover regimes that amplified the production of higher reward behaviors through two key mechanisms: repertoire composition and enhanced valuation by agents that knew both behaviors. These effects depended on network and learning parameters. Our model provides formal theoretical support for, and predictions about, the hypothesis that naive learners can shape cultural change through their enhanced sampling ability. By moving from experimental data to theory, we illuminate an underdiscussed generative process that can lead to changes in cultural behavior, arising from an interaction between social dynamics and learning.
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Déaux EC, Bonneaud C, Baumeyer A, Zuberbühler K. Do chimpanzee food calls bias listeners toward novel items? Am J Primatol 2023:e23498. [PMID: 37113057 DOI: 10.1002/ajp.23498] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2021] [Revised: 04/03/2023] [Accepted: 04/15/2023] [Indexed: 04/29/2023]
Abstract
Social learning is beneficial in almost every domain of a social animal's life, but it is particularly important in the context of predation and foraging. In both contexts, social animals tend to produce acoustically distinct vocalizations, alarms, and food calls, which have remained somewhat of an evolutionary conundrum as they appear to be costly for the signaller. Here, we investigated the hypothesis that food calls function to direct others toward novel food items, using a playback experiment on a group of chimpanzees. We showed chimpanzees novel (plausibly edible) items while simultaneously playing either conspecific food calls or acoustically similar greeting calls as a control. We found that individuals responded by staying longer near items previously associated with food calls even in the absence of these vocalizations, and peered more at these items compared with the control items, provided no conspecifics were nearby. We also found that once chimpanzees had access to both item types, they interacted more with the one previously associated with food calls than the control items. However, we found no evidence of social learning per se. Given these effects, we propose that food calls may gate and thus facilitate social learning by directing listeners' attention to new feeding opportunities, which if integrated with additional cues could ultimately lead to new food preferences within social groups.
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Affiliation(s)
- Eloïse C Déaux
- Institue of Biology, University of Neuchatel, Neuchatel, Switzerland
| | - Clémence Bonneaud
- Institue of Biology, University of Neuchatel, Neuchatel, Switzerland
| | | | - Klaus Zuberbühler
- Institue of Biology, University of Neuchatel, Neuchatel, Switzerland
- School of Psychology and Neurosciences, University of St Andrews, St Andrews, Scotland, UK
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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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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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6
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Goldsborough Z, Sterck EHM, de Waal FBM, Webb CE. Individual variation in chimpanzee (Pan troglodytes) repertoires of abnormal behaviour. Anim Welf 2022. [DOI: 10.7120/09627286.31.1.011] [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
Abnormal behaviour in captive animals is both pervasive and ambiguous. Although individual differences are central to the field of animal welfare, studies on abnormal behaviour predominantly employ quantitative, population-level approaches. For example, whereas previous studies on chimpanzee
(Pan troglodytes) abnormal behaviour have reported significant variation between groups or individuals in the quantity (eg frequency and duration) of abnormal behaviour, much less is known about qualitative differences. Individual abnormal behavioural repertoires may be highly idiosyncratic,
where certain behaviours are over-represented (ie individually specific abnormal behavioural 'signatures'). The present study investigated qualitative individual variation in the abnormal behaviour of chimpanzees (n = 15) housed at Royal Burgers' Zoo in Arnhem, The Netherlands. Substantial
variation was found between individuals in the diversity (size and evenness) and overall composition of their abnormal behavioural repertoires. Factors including age, sex, and rank did not significantly account for dissimilarity of individuals' abnormal behavioural repertoires, but kin dyads
showed more similar abnormal behaviour than non-kin dyads. Further exploratory analyses examined whether individual variation in one abnormal behaviour (coprophagy) predicted variation in stress-related behaviour (self-scratching). This allowed us to tentatively conclude that there were also
individual differences in the link between a given abnormal behaviour and the behavioural expression of stress. Qualitative individual variation in abnormal behaviour provides a novel angle to a literature traditionally focused on quantifying abnormal behaviour at the group- or species-level
and may thus represent an important yet previously overlooked source of variation in the extent to which abnormal behaviour reflects the state of individual welfare.
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Affiliation(s)
- Z Goldsborough
- Animal Behaviour & Cognition, Department of Biology, Utrecht University, Utrecht, The Netherlands
| | - EHM Sterck
- Animal Behaviour & Cognition, Department of Biology, Utrecht University, Utrecht, The Netherlands
| | - FBM de Waal
- Animal Behaviour & Cognition, Department of Biology, Utrecht University, Utrecht, The Netherlands
| | - CE Webb
- Animal Behaviour & Cognition, Department of Biology, Utrecht University, Utrecht, The Netherlands
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8
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Sheppard CE, Heaphy R, Cant MA, Marshall HH. Individual foraging specialization in group-living species. Anim Behav 2021. [DOI: 10.1016/j.anbehav.2021.10.011] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
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9
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Insights from comparative research on social and cultural learning. PROGRESS IN BRAIN RESEARCH 2021; 254:247-270. [PMID: 32859290 DOI: 10.1016/bs.pbr.2020.05.008] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/13/2023]
Abstract
Social cognitive skills play a crucial role in human life, and have allowed us to reach a unique level of behavioral and cultural complexity. However, many nonhuman species also show a complex understanding of the social world. Building on theories of human social development, we will follow the emergence of cultural learning skills across taxa, discussing similarities and differences between humans and other species. We will first review literature on social learning, including enhancement, emulation and imitation. Then, we will discuss existing studies on the evolution of teaching, and finally, we will critically review literature on the social transmission of skills and knowledge across generations. By adopting a comparative perspective, we will be able to identify the unique characteristics of social transmission in humans, and the social skills that are instead shared with other species, to gain a deeper understanding of the role of cultural learning in social cognitive development.
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10
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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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11
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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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12
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Leca JB, Gunst N, Gardiner M, Wandia IN. Acquisition of object-robbing and object/food-bartering behaviours: a culturally maintained token economy in free-ranging long-tailed macaques. Philos Trans R Soc Lond B Biol Sci 2021; 376:20190677. [PMID: 33423623 PMCID: PMC7815422 DOI: 10.1098/rstb.2019.0677] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
The token exchange paradigm shows that monkeys and great apes are able to use objects as symbolic tools to request specific food rewards. Such studies provide insights into the cognitive underpinnings of economic behaviour in non-human primates. However, the ecological validity of these laboratory-based experimental situations tends to be limited. Our field research aims to address the need for a more ecologically valid primate model of trading systems in humans. Around the Uluwatu Temple in Bali, Indonesia, a large free-ranging population of long-tailed macaques spontaneously and routinely engage in token-mediated bartering interactions with humans. These interactions occur in two phases: after stealing inedible and more or less valuable objects from humans, the macaques appear to use them as tokens, by returning them to humans in exchange for food. Our field observational and experimental data showed (i) age differences in robbing/bartering success, indicative of experiential learning, and (ii) clear behavioural associations between value-based token possession and quantity or quality of food rewards rejected and accepted by subadult and adult monkeys, suggestive of robbing/bartering payoff maximization and economic decision-making. This population-specific, prevalent, cross-generational, learned and socially influenced practice may be the first example of a culturally maintained token economy in free-ranging animals. This article is part of the theme issue ‘Existence and prevalence of economic behaviours among non-human primates'.
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Affiliation(s)
- Jean-Baptiste Leca
- Department of Psychology, University of Lethbridge, Lethbridge, Alberta, Canada T1K 3M4
| | - Noëlle Gunst
- Department of Psychology, University of Lethbridge, Lethbridge, Alberta, Canada T1K 3M4
| | - Matthew Gardiner
- Department of Psychology, University of Lethbridge, Lethbridge, Alberta, Canada T1K 3M4
| | - I Nengah Wandia
- Faculty of Veterinary Medicine, Udayana University, Bukit Jimbaran, Bali, Indonesia
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13
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O'Bryan LR, Lambeth SP, Schapiro SJ, Wilson ML. Unpacking chimpanzee (Pan troglodytes) patch use: Do individuals respond to food patches as predicted by the marginal value theorem? Am J Primatol 2020; 82:e23208. [PMID: 33118192 DOI: 10.1002/ajp.23208] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2020] [Revised: 09/30/2020] [Accepted: 10/03/2020] [Indexed: 01/06/2023]
Abstract
The marginal value theorem is an optimal foraging model that predicts how efficient foragers should respond to both their ecological and social environments when foraging in food patches, and it has strongly influenced hypotheses for primate behavior. Nevertheless, experimental tests of the marginal value theorem have been rare in primates and observational studies have provided conflicting support. As a step towards filling this gap, we test whether the foraging decisions of captive chimpanzees (Pan troglodytes) adhere to the assumptions and qualitative predictions of the marginal value theorem. We presented 12 adult chimpanzees with a two-patch foraging environment consisting of both low-quality (i.e., low-food density) and high-quality (i.e., high-food density) patches and examined the effect of patch quality on their search behavior, foraging duration, marginal capture rate, and its proxy measures: giving-up density and giving-up time. Chimpanzees foraged longer in high-quality patches, as predicted. In contrast to predictions, they did not depress high-quality patches as thoroughly as low-quality patches. Furthermore, since chimpanzees searched in a manner that fell between systematic and random, their intake rates did not decline at a steady rate over time, especially in high-quality patches, violating an assumption of the marginal value theorem. Our study provides evidence that chimpanzees are sensitive to their rate of energy intake and that their foraging durations correlate with patch quality, supporting many assumptions underlying primate foraging and social behavior. However, our results question whether the marginal value theorem is a constructive model of chimpanzee foraging behavior, and we suggest a Bayesian foraging framework (i.e., combining past foraging experiences with current patch sampling information) as a potential alternative. More work is needed to build an understanding of the proximate mechanisms underlying primate foraging decisions, especially in more complex socioecological environments.
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Affiliation(s)
- Lisa R O'Bryan
- Department of Ecology, Evolution and Behavior, University of Minnesota, St. Paul, Minnesota, USA.,Department of Psychological Sciences, Rice University, Houston, Texas, USA
| | - Susan P Lambeth
- Department of Comparative Medicine, Michale E. Keeling Center for Comparative Medicine and Research, UT MD Anderson Cancer Center, Bastrop, Texas, USA
| | - Steven J Schapiro
- Department of Comparative Medicine, Michale E. Keeling Center for Comparative Medicine and Research, UT MD Anderson Cancer Center, Bastrop, Texas, USA
| | - Michael L Wilson
- Department of Ecology, Evolution and Behavior, University of Minnesota, St. Paul, Minnesota, USA.,Department of Anthropology, University of Minnesota, Minneapolis, Minnesota, USA
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14
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Hopper LM, Jacobson SL, Howard LH. Problem solving flexibility across early development. J Exp Child Psychol 2020; 200:104966. [PMID: 32860967 PMCID: PMC7449664 DOI: 10.1016/j.jecp.2020.104966] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2020] [Revised: 07/24/2020] [Accepted: 07/24/2020] [Indexed: 11/17/2022]
Abstract
We tested cognitive flexibility in 2-, 3, and 4-year-old children. Children were presented with a novel task previously used with nonhuman primates. All children spontaneously solved the task; most (83.61%) used an efficient method. Children responded flexibly when task demands changed. 4-year-olds were significantly more efficient than 2-year-olds.
Cognitive flexibility allows individuals to adapt to novel situations. However, this ability appears to develop slowly over the first few years of life, mediated by task complexity and opacity. We used a physically simple novel task, previously tested with nonhuman primates, to explore the development of flexible problem solving in 2-, 3-, and 4-year-old children from a developmental and comparative perspective. The task goal was to remove barriers (straws) from a clear tube to release a ball. The location of the ball, and therefore the number of straws necessary to retrieve it, varied across two test phases (four of five straws and two of five straws, respectively). In Test Phase 1, all children retrieved the ball in Trial 1 and 83.61% used the most efficient method (removing only straws below the ball). Across Phase 1 trials, 4-year-olds were significantly more efficient than 2-year-olds, and solve latency decreased for all age groups. Test Phase 2 altered the location of the ball, allowing us to explore whether children could flexibly adopt a more efficient solution when their original (now inefficient) solution remained available. In Phase 2, significantly more 4-year-olds than 2-year-olds were efficient; the older children showed greater competency with the task and were more flexible to changing task demands than the younger children. Interestingly, no age group was as flexible in Phase 2 as previously tested nonhuman primates, potentially related to their relatively reduced task exploration in Phase 1. Therefore, this causally clear task revealed changes in cognitive flexibility across both early childhood and species.
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Affiliation(s)
- Lydia M Hopper
- Lester E. Fisher Center for the Study and Conservation of Apes, Lincoln Park Zoo, Chicago, IL 60614, USA.
| | - Sarah L Jacobson
- Program in Psychology, Graduate Center, City University of New York, New York, NY 10016, USA
| | - Lauren H Howard
- Department of Psychology, Franklin & Marshall College, Lancaster, PA 17603, USA
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15
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Neadle D, Bandini E, Tennie C. Testing the individual and social learning abilities of task-naïve captive chimpanzees ( Pan troglodytes sp.) in a nut-cracking task. PeerJ 2020; 8:e8734. [PMID: 32195057 PMCID: PMC7069405 DOI: 10.7717/peerj.8734] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2019] [Accepted: 02/11/2020] [Indexed: 11/20/2022] Open
Abstract
Nut-cracking is often cited as one of the most complex behaviours observed in wild chimpanzees. However, the cognitive mechanisms behind its acquisition are still debated. The current null hypothesis is that the form of nut-cracking behaviour relies on variants of social learning, with some researchers arguing, more precisely, that copying variants of social learning mechanisms are necessary. However, to date, very few experiments have directly investigated the potentially sufficient role of individual learning in explaining the behavioural form of nut-cracking. Despite this, the available data provides some evidence for the spontaneous acquisition of nut-cracking by chimpanzees; later group acquisition was then found to be at least facilitated by (unspecified) variants of social learning. The latter findings are in line with both suggested hypotheses, i.e., that copying social learning is required and that other (non-copying) social learning mechanisms are at play. Here we present the first study which focused (initially) on the role of individual learning for the acquisition of the nut-cracking behavioural form in chimpanzees. We tested task-naïve chimpanzees (N = 13) with an extended baseline condition to examine whether the behaviour would emerge spontaneously. After the baseline condition (which was unsuccessful), we tested for the role of social learning by providing social information in a step-wise fashion, culminating in a full action demonstration of nut-cracking by a human demonstrator (this last condition made it possible for the observers to copy all actions underlying the behaviour). Despite the opportunities to individually and/or socially learn nut-cracking, none of the chimpanzees tested here cracked nuts using tools in any of the conditions in our study; thus, providing no conclusive evidence for either competing hypothesis. We conclude that this failure was the product of an interplay of factors, including behavioural conservatism and the existence of a potential sensitive learning period for nut-cracking in chimpanzees. The possibility remains that nut-cracking is a behaviour that chimpanzees can individually learn. However, this behaviour might only be acquired when chimpanzees are still inside their sensitive learning period, and when ecological and developmental conditions allow for it. The possibility remains that nut-cracking is an example of a culture dependent trait in non-human great apes. Recommendations for future research projects to address this question are considered.
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Affiliation(s)
- Damien Neadle
- School of Psychology, College of Life and Environmental Sciences, University of Birmingham, Birmingham, United Kingdom.,Department of Psychology, School of Social Sciences, Faculty of Business, Law and Social Sciences, Birmingham City University, Birmingham, United Kingdom
| | - Elisa Bandini
- Department of Early Prehistory and Quaternary Ecology, Eberhard-Karls-Universität Tübingen, Tübingen, Germany
| | - Claudio Tennie
- Department of Early Prehistory and Quaternary Ecology, Eberhard-Karls-Universität Tübingen, Tübingen, Germany
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Huskisson SM, Jacobson SL, Egelkamp CL, Ross SR, Hopper LM. Using a Touchscreen Paradigm to Evaluate Food Preferences and Response to Novel Photographic Stimuli of Food in Three Primate Species (Gorilla gorilla gorilla, Pan troglodytes, and Macaca fuscata). INT J PRIMATOL 2020. [DOI: 10.1007/s10764-020-00131-0] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
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Addessi E, Beran MJ, Bourgeois-Gironde S, Brosnan SF, Leca JB. Are the roots of human economic systems shared with non-human primates? Neurosci Biobehav Rev 2019; 109:1-15. [PMID: 31874185 DOI: 10.1016/j.neubiorev.2019.12.026] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2019] [Revised: 11/14/2019] [Accepted: 12/16/2019] [Indexed: 11/19/2022]
Abstract
We review and analyze evidence for an evolutionary rooting of human economic behaviors and organization in non-human primates. Rather than focusing on the direct application of economic models that a priori account for animal decision behavior, we adopt an inductive definition of economic behavior in terms of the contribution of individual cognitive capacities to the provision of resources within an exchange structure. We spell out to what extent non-human primates' individual and strategic decision behaviors are shared with humans. We focus on the ability to trade, through barter or token-mediated exchanges, as a landmark of an economic system among members of the same species. It is an open question why only humans have reached a high level of economic sophistication. While primates have many of the necessary cognitive abilities (symbolic and computational) in isolation, one plausible issue we identify is the limits in exerting cognitive control to combine several sources of information. The difference between human and non-human primates' economies might well then be in degree rather than kind.
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Affiliation(s)
- Elsa Addessi
- ISTC-CNR, Via Ulisse Aldrovandi 16/b, 00197, Rome, Italy
| | - Michael J Beran
- Department of Psychology Georgia State University P.O. Box 5010 Atlanta, GA 30302-5010, USA; Language Research Center, The Neuroscience Institute, Georgia State University, PO Box 5010, Atlanta, GA 30302-5010, USA
| | - Sacha Bourgeois-Gironde
- Institut Jean Nicod, Département d'études cognitives, ENS, EHESS, CNRS, PSL University, UMR 8129, 29 rue d'Ulm, 75005 Paris, France.
| | - Sarah F Brosnan
- Department of Psychology Georgia State University P.O. Box 5010 Atlanta, GA 30302-5010, USA; Language Research Center, The Neuroscience Institute, Georgia State University, PO Box 5010, Atlanta, GA 30302-5010, USA; The Center for Behavioral Neuroscience, Georgia State University, Atlanta, GA, USA
| | - Jean-Baptiste Leca
- Department of Psychology, University of Lethbridge Lethbridge, Alberta, T1K 3M4, Canada
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18
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Brotcorne F, Holzner A, Jorge-Sales L, Gunst N, Hambuckers A, Wandia IN, Leca JB. Social influence on the expression of robbing and bartering behaviours in Balinese long-tailed macaques. Anim Cogn 2019; 23:311-326. [PMID: 31820148 DOI: 10.1007/s10071-019-01335-5] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2019] [Revised: 11/20/2019] [Accepted: 12/02/2019] [Indexed: 01/01/2023]
Abstract
Animals use social information, available from conspecifics, to learn and express novel and adaptive behaviours. Amongst social learning mechanisms, response facilitation occurs when observing a demonstrator performing a behaviour temporarily increases the probability that the observer will perform the same behaviour shortly after. We studied "robbing and bartering" (RB), two behaviours routinely displayed by free-ranging long-tailed macaques (Macaca fascicularis) at Uluwatu Temple, Bali, Indonesia. When robbing, a monkey steals an inedible object from a visitor and may use this object as a token by exchanging it for food with the temple staff (bartering). We tested whether the expression of RB-related behaviours could be explained by response facilitation and was influenced by model-based biases (i.e. dominance rank, age, experience and success of the demonstrator). We compared video-recorded focal samples of 44 witness individuals (WF) immediately after they observed an RB-related event performed by group members, and matched-control focal samples (MCF) of the same focal subjects, located at similar distance from former demonstrators (N = 43 subjects), but in the absence of any RB-related demonstrations. We found that the synchronized expression of robbing and bartering could be explained by response facilitation. Both behaviours occurred significantly more often during WF than during MCF. Following a contagion-like effect, the rate of robbing behaviour displayed by the witness increased with the cumulative rate of robbing behaviour performed by demonstrators, but this effect was not found for the bartering behaviour. The expression of RB was not influenced by model-based biases. Our results support the cultural nature of the RB practice in the Uluwatu macaques.
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Affiliation(s)
- Fany Brotcorne
- Research Unit SPHERES, University of Liège, Liège, Belgium.
| | - Anna Holzner
- School of Biological Sciences, Universiti Sains Malaysia, Penang, Malaysia
| | - Lucía Jorge-Sales
- Primate Conservation and Sustainable Development, Miku Conservación AC, Mérida, México
| | - Noëlle Gunst
- Department of Psychology, University of Lethbridge, Lethbridge, Canada
| | | | - I Nengah Wandia
- Primate Research Center, Universitas Udayana, Bali, Indonesia
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19
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Canteloup C. Qui copier ? Les stratégies d’apprentissage social chez les animaux. REVUE DE PRIMATOLOGIE 2019. [DOI: 10.4000/primatologie.4326] [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
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20
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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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21
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Lauderdale LK, Miller LJ. Common bottlenose dolphin (Tursiops truncatus) problem solving strategies in response to a novel interactive apparatus. Behav Processes 2019; 169:103990. [PMID: 31678324 DOI: 10.1016/j.beproc.2019.103990] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2019] [Revised: 10/21/2019] [Accepted: 10/22/2019] [Indexed: 11/29/2022]
Abstract
The problem solving capabilities of dolphins are suggested to be indicative of advanced cognition. When confronted with a novel problem, dolphins can plan their behavior to create a more efficient strategy than that which was previously modeled. The present study investigated dolphins' ability to plan their behaviors using an interactive apparatus with accompanying weights. Two problems were presented to evaluate dolphins' ability to plan by collecting several weights at once, thus solving the apparatus more efficiently. In contrast to previous findings, dolphins in the present study failed to plan their behavior. Rather, individual differences in problem solving strategies arose throughout the study and are described here. Dolphins engaged in several strategies in order to attempt to obtain the fish reward, including approaches that were not modeled. Strategies for solving the submerged interactive apparatus (SIA) included emulation, freeloading, water flow manipulation, and physical manipulation of the SIA. The SIA was continually solved by a single individual who rarely consumed the food reward, suggesting that she may have been motivated to participate for the challenge itself. Though not indicative of planning, the results of the present study demonstrate the plasticity of dolphin problem solving capabilities and spatial reasoning.
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Affiliation(s)
- L K Lauderdale
- Department of Psychology, University of Southern Mississippi, 118 College Drive, Hattiesburg, MS 39406, USA; Chicago Zoological Society, Brookfield Zoo, 3300 Golf Road, Brookfield, IL 60513, USA
| | - L J Miller
- Chicago Zoological Society, Brookfield Zoo, 3300 Golf Road, Brookfield, IL 60513, USA
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22
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Caldwell CA, Atkinson M, Blakey KH, Dunstone J, Kean D, Mackintosh G, Renner E, Wilks CEH. Experimental assessment of capacities for cumulative culture: Review and evaluation of methods. WILEY INTERDISCIPLINARY REVIEWS. COGNITIVE SCIENCE 2019; 11:e1516. [PMID: 31441239 PMCID: PMC6916575 DOI: 10.1002/wcs.1516] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/24/2019] [Revised: 07/17/2019] [Accepted: 07/19/2019] [Indexed: 12/28/2022]
Abstract
In the current literature, there are few experimental tests of capacities for cumulative cultural evolution in nonhuman species. There are even fewer examples of such tests in young children. This limited evidence is noteworthy given widespread interest in the apparent distinctiveness of human cumulative culture, and the potentially significant theoretical implications of identifying related capacities in nonhumans or very young children. We evaluate experimental methods upon which claims of capacities for cumulative culture, or lack thereof, have been based. Although some of the established methods (those simulating generational succession) have the potential to identify positive evidence that fulfills widely accepted definitions of cumulative culture, the implementation of these methods entails significant logistical challenges. This is particularly true for testing populations that are difficult to access in large numbers, or those not amenable to experimental control. This presents problems for generating evidence that would be sufficient to support claims of capacities for cumulative culture, and these problems are magnified for establishing convincing negative evidence. We discuss alternative approaches to assessing capacities for cumulative culture, which circumvent logistical problems associated with experimental designs involving chains of learners. By inferring the outcome of repeated transmission from the input–output response patterns of individual subjects, sample size requirements can be massively reduced. Such methods could facilitate comparisons between populations, for example, different species, or children of a range of ages. We also detail limitations and challenges of this alternative approach, and discuss potential avenues for future research. This article is categorized under:Cognitive Biology > Evolutionary Roots of Cognition Cognitive Biology > Cognitive Development Psychology > Comparative Psychology
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Affiliation(s)
| | - Mark Atkinson
- Division of Psychology, University of Stirling, Stirling, Scotland
| | - Kirsten H Blakey
- Division of Psychology, University of Stirling, Stirling, Scotland
| | - Juliet Dunstone
- Division of Psychology, University of Stirling, Stirling, Scotland
| | - Donna Kean
- Division of Psychology, University of Stirling, Stirling, Scotland
| | - Gemma Mackintosh
- Division of Psychology, University of Stirling, Stirling, Scotland
| | - Elizabeth Renner
- Division of Psychology, University of Stirling, Stirling, Scotland
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23
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Shorland G, Genty E, Guéry JP, Zuberbühler K. Social learning of arbitrary food preferences in bonobos. Behav Processes 2019; 167:103912. [PMID: 31344448 DOI: 10.1016/j.beproc.2019.103912] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2019] [Revised: 07/20/2019] [Accepted: 07/20/2019] [Indexed: 12/30/2022]
Abstract
A fruitful approach to investigate social learning in animals is based on paradigms involving the manipulation of artefacts. However, tool use and elaborate object manipulations are rare in natural conditions, suggesting that social learning evolved in other contexts where fitness consequences are higher, such as discriminating palatable from noxious foods, recognising predators or understanding social hierarchies. We focussed on one such context by investigating whether bonobos socially learned others' arbitrary food preferences through mere observation. To this end, we trained two demonstrators to prefer or avoid distinctly coloured food items, treated with either a sweet or bitter agent. Demonstrators then displayed their newly acquired preferences in front of naïve subjects. In subsequent choice tests, subjects generally matched their choices to the demonstrators' preferred food colours, despite having already tasted the equally palatable colour alternative. Both age and exposure to demonstrator preference had a significant positive effect on the proportion of matched choices. Moreover, in a context where errors can be costly, social learning was instant insofar as six of seven subjects used socially learned information to influence their very first food choice. We discuss these findings in light of the current debate on the evolution of social learning in animals.
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Affiliation(s)
- Gladez Shorland
- Department of Comparative Cognition, Institute of Biology, University of Neuchâtel, Rue Emile-Argand 11, 2000, Neuchâtel, Switzerland.
| | - Emilie Genty
- Department of Comparative Cognition, Institute of Biology, University of Neuchâtel, Rue Emile-Argand 11, 2000, Neuchâtel, Switzerland; Institute of Work and Organizational Psychology, University of Neuchâtel, Rue Emile-Argand 11, 2000, Neuchâtel, Switzerland
| | - Jean-Pascal Guéry
- La Vallée des Singes Primate park, Le Gureau, 86700, Romagne, France
| | - Klaus Zuberbühler
- Department of Comparative Cognition, Institute of Biology, University of Neuchâtel, Rue Emile-Argand 11, 2000, Neuchâtel, Switzerland; School of Psychology and Neurosciences, University of St Andrews, St Mary's Quad, South Street, St Andrews, KY16 9JP, UK
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24
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Abstract
Typically, animals' food preferences are tested manually, which can be both time-consuming and vulnerable to experimenter biases. Given the utility of ascertaining animals' food preferences for research and husbandry protocols, developing a quick, reliable, and flexible paradigm would be valuable for expediting many research protocols. Therefore, we evaluated the efficacy of using a touchscreen interface to test nonhuman primates' food preferences and valuations, adapting previously validated manual methods. We tested a nonhuman primate subject with four foods (carrot, cucumber, grape, and turnip). Preference testing followed a pairwise forced choice protocol with pairs of food images presented on a touchscreen: The subject was rewarded with whichever food was selected. All six possible pairwise combinations were presented, with 90 trials per pairing. Second, we measured how hard the subject was willing to work to obtain each of the four foods, allowing us to generate demand curves. For this phase, a single image of a food item was presented on the touchscreen that the subject had to select in order to receive the food, and the number of selections required increased following a quarter-log scale, with ten trials per cost level (1, 2, 3, 6, 10, and 18). These methods allowed us to ascertain the subject's relative preferences and valuations of the four foods. The success of this touchscreen protocol for testing the subject's food preferences, from both a practical and a theoretical standpoint, suggests that the protocol should be further validated with other foods with this subject, with other subjects, and with other test items.
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26
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Foraging in a social setting: a comparative analysis of captive gorillas and chimpanzees. Primates 2019; 60:125-131. [PMID: 30806863 DOI: 10.1007/s10329-018-00712-x] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2018] [Accepted: 12/20/2018] [Indexed: 10/27/2022]
Abstract
This study was designed to investigate the foraging behavior of zoo-housed western lowland gorillas (Gorilla gorilla gorilla) and compare it with that of zoo-housed chimpanzees (Pan trogloydytes) tested previously in a similar paradigm. Specifically, we aimed to document how a group of zoo-housed gorillas foraged within a familiar environment to discover novel food sources and whether they sought out more preferred foods, even if they had to travel further to reach them, as they do in the wild. Gorillas were provided plastic tokens to exchange with researchers at two locations-at the same location as the tokens (close) for carrot pieces and another 6.5 m away (far) for grapes. Over the course of 30 sessions, a single individual-the silverback male-accounted for 96% of the 1546 tokens exchanged, all of which took place at the far location. Inter-individual distance measures collected during each session, as well as during matched control sessions, showed that while both gorillas and chimpanzees express similar patterns of social association across the two conditions, the average dyadic association for chimpanzees was stronger than that for gorillas. Together, these findings provide an example of the value of employing identical methodologies to compare cognition and behavior across species as well highlight the importance of the social context in which studies take place.
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27
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Jacobson SL, Hopper LM. Hardly habitual: chimpanzees and gorillas show flexibility in their motor responses when presented with a causally-clear task. PeerJ 2019; 7:e6195. [PMID: 30643700 PMCID: PMC6329335 DOI: 10.7717/peerj.6195] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2018] [Accepted: 12/01/2018] [Indexed: 11/25/2022] Open
Abstract
In contrast to reports of wild primates, studies of captive primates’ flexibility often reveal conservatism: individuals are unable to switch to new and more efficient strategies when task demands change. We propose that such conservatism might be a result of task design and hypothesize that conservatism might be linked to primates’ lack of causal understanding in relation to experimental apparatuses. We investigated if chimpanzees (Pan troglodytes) and western lowland gorillas (Gorilla gorilla gorilla) would show greater flexibility when presented with a causally-clear task. We presented six chimpanzees and seven gorillas with a clear tube from which they had to remove straws to release a reward. To first evaluate the apes’ causal understanding, we recorded the efficiency with which the apes solved the task (i.e., whether they only removed straws below the reward, ignoring redundant ones above it). To further explore how they solved the task, we also recorded the order in which they removed the straws, which allowed us to determine if habitual action sequences emerged. All apes spontaneously solved the task in their first trial and across repeated trials the majority of their solutions were efficient (median = 90.9%), demonstrating their understanding of the puzzle. There was individual variation in the consistency of straw removal patterns exhibited by the apes, but no ape developed an exclusive habit in the order with which they removed the straws, further indicating their causal understanding of the task. Next, we presented the apes with a new configuration of the same task that required the apes to remove fewer straws to obtain the reward. All apes switched to a more efficient straw removal sequence even though their previously-successful, but now less-efficient, solution remained available. We theorize that because the apes understood the causality of the task, they did not form habits and were not conservative.
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Affiliation(s)
- Sarah L Jacobson
- Psychology, City University of New York, Graduate School and University Center, New York, NY, United States of America.,Lester E. Fisher Center for the Study and Conservation of Apes, Lincoln Park Zoo, Chicago, IL, United States of America
| | - Lydia M Hopper
- Lester E. Fisher Center for the Study and Conservation of Apes, Lincoln Park Zoo, Chicago, IL, United States of America
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28
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Vale GL, Flynn EG, Kendal J, Rawlings B, Hopper LM, Schapiro SJ, Lambeth SP, Kendal RL. Testing differential use of payoff-biased social learning strategies in children and chimpanzees. Proc Biol Sci 2018; 284:rspb.2017.1751. [PMID: 29187629 PMCID: PMC5740275 DOI: 10.1098/rspb.2017.1751] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2017] [Accepted: 10/26/2017] [Indexed: 11/12/2022] Open
Abstract
Various non-human animal species have been shown to exhibit behavioural traditions. Importantly, this research has been guided by what we know of human culture, and the question of whether animal cultures may be homologous or analogous to our own culture. In this paper, we assess whether models of human cultural transmission are relevant to understanding biological fundamentals by investigating whether accounts of human payoff-biased social learning are relevant to chimpanzees (Pan troglodytes). We submitted 4- and 5-year-old children (N = 90) and captive chimpanzees (N = 69) to a token–reward exchange task. The results revealed different forms of payoff-biased learning across species and contexts. Specifically, following personal and social exposure to different tokens, children's exchange behaviour was consistent with proportional imitation, where choice is affected by both prior personally acquired and socially demonstrated token–reward information. However, when the socially derived information regarding token value was novel, children's behaviour was consistent with proportional observation; paying attention to socially derived information and ignoring their prior personal experience. By contrast, chimpanzees' token choice was governed by their own prior experience only, with no effect of social demonstration on token choice, conforming to proportional reservation. We also find evidence for individual- and group-level differences in behaviour in both species. Despite the difference in payoff strategies used, both chimpanzees and children adopted beneficial traits when available. However, the strategies of the children are expected to be the most beneficial in promoting flexible behaviour by enabling existing behaviours to be updated or replaced with new and often superior ones.
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Affiliation(s)
- Gillian L Vale
- National Center for Chimpanzee Care, Michale E. Keeling Center for Comparative Medicine and Research, The University of Texas MD Anderson Cancer Center, Bastrop, TX, USA .,Department of Psychology and Language Research Center, Georgia State University, Atlanta, GA, USA
| | - Emma G Flynn
- Centre for the Coevolution of Biology and Culture, Durham University, Durham, UK
| | - Jeremy Kendal
- Centre for the Coevolution of Biology and Culture, Durham University, Durham, UK
| | - Bruce Rawlings
- Centre for the Coevolution of Biology and Culture, Durham University, Durham, UK
| | - Lydia M Hopper
- Lester E. Fisher Center for the Study and Conservation of Apes, Lincoln Park Zoo, Chicago, IL, USA
| | - Steven J Schapiro
- National Center for Chimpanzee Care, Michale E. Keeling Center for Comparative Medicine and Research, The University of Texas MD Anderson Cancer Center, Bastrop, TX, USA
| | - Susan P Lambeth
- National Center for Chimpanzee Care, Michale E. Keeling Center for Comparative Medicine and Research, The University of Texas MD Anderson Cancer Center, Bastrop, TX, USA
| | - Rachel L Kendal
- Centre for the Coevolution of Biology and Culture, Durham University, Durham, UK
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Sheppard CE, Inger R, McDonald RA, Barker S, Jackson AL, Thompson FJ, Vitikainen EIK, Cant MA, Marshall HH, Bourke A. Intragroup competition predicts individual foraging specialisation in a group-living mammal. Ecol Lett 2018; 21:665-673. [PMID: 29542220 PMCID: PMC5947261 DOI: 10.1111/ele.12933] [Citation(s) in RCA: 47] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2017] [Revised: 11/08/2017] [Accepted: 02/06/2018] [Indexed: 01/12/2023]
Abstract
Individual foraging specialisation has important ecological implications, but its causes in group-living species are unclear. One of the major consequences of group living is increased intragroup competition for resources. Foraging theory predicts that with increased competition, individuals should add new prey items to their diet, widening their foraging niche ('optimal foraging hypothesis'). However, classic competition theory suggests the opposite: that increased competition leads to niche partitioning and greater individual foraging specialisation ('niche partitioning hypothesis'). We tested these opposing predictions in wild, group-living banded mongooses (Mungos mungo), using stable isotope analysis of banded mongoose whiskers to quantify individual and group foraging niche. Individual foraging niche size declined with increasing group size, despite all groups having a similar overall niche size. Our findings support the prediction that competition promotes niche partitioning within social groups and suggest that individual foraging specialisation may play an important role in the formation of stable social groupings.
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Affiliation(s)
- Catherine E. Sheppard
- Centre for Ecology and ConservationUniversity of ExeterPenryn CampusCornwallTR10 9FEUK
| | - Richard Inger
- Environment and Sustainability InstituteUniversity of ExeterPenryn CampusCornwallTR10 9FEUK
| | - Robbie A. McDonald
- Environment and Sustainability InstituteUniversity of ExeterPenryn CampusCornwallTR10 9FEUK
| | - Sam Barker
- Environment and Sustainability InstituteUniversity of ExeterPenryn CampusCornwallTR10 9FEUK
| | - Andrew L. Jackson
- Department of ZoologySchool of Natural SciencesTrinity College DublinDublin 2Ireland
| | - Faye J. Thompson
- Centre for Ecology and ConservationUniversity of ExeterPenryn CampusCornwallTR10 9FEUK
| | - Emma I. K. Vitikainen
- Centre for Ecology and ConservationUniversity of ExeterPenryn CampusCornwallTR10 9FEUK
- Department of BiosciencesUniversity of HelsinkiPO Box 65 (Viikinkaari 1)HelsinkiFI‐00014Finland
| | - Michael A. Cant
- Centre for Ecology and ConservationUniversity of ExeterPenryn CampusCornwallTR10 9FEUK
| | - Harry H. Marshall
- Centre for Ecology and ConservationUniversity of ExeterPenryn CampusCornwallTR10 9FEUK
- Centre for Research in Ecology, Evolution and BehaviourUniversity of RoehamptonLondonSW15 4JDUK
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30
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Chimpanzees prioritise social information over pre-existing behaviours in a group context but not in dyads. Anim Cogn 2018; 21:407-418. [PMID: 29574554 PMCID: PMC5908815 DOI: 10.1007/s10071-018-1178-y] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2017] [Revised: 03/05/2018] [Accepted: 03/16/2018] [Indexed: 11/23/2022]
Abstract
How animal communities arrive at homogeneous behavioural preferences is a central question for studies of cultural evolution. Here, we investigated whether chimpanzees (Pan troglodytes) would relinquish a pre-existing behaviour to adopt an alternative demonstrated by an overwhelming majority of group mates; in other words, whether chimpanzees behave in a conformist manner. In each of five groups of chimpanzees (N = 37), one individual was trained on one method of opening a two-action puzzle box to obtain food, while the remaining individuals learned the alternative method. Over 5 h of open access to the apparatus in a group context, it was found that 4/5 ‘minority’ individuals explored the majority method and three of these used this new method in the majority of trials. Those that switched did so after observing only a small subset of their group, thereby not matching conventional definitions of conformity. In a further ‘Dyad’ condition, six pairs of chimpanzees were trained on alternative methods and then given access to the task together. Only one of these individuals ever switched method. The number of observations that individuals in the minority and Dyad individuals made of their untrained method was not found to influence whether or not they themselves switched to use it. In a final ‘Asocial’ condition, individuals (N = 10) did not receive social information and did not deviate from their first-learned method. We argue that these results demonstrate an important influence of social context upon prioritisation of social information over pre-existing methods, which can result in group homogeneity of behaviour.
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31
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Whiten A, van de Waal E. Social learning, culture and the ‘socio-cultural brain’ of human and non-human primates. Neurosci Biobehav Rev 2017; 82:58-75. [DOI: 10.1016/j.neubiorev.2016.12.018] [Citation(s) in RCA: 39] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2016] [Revised: 12/15/2016] [Accepted: 12/19/2016] [Indexed: 01/14/2023]
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32
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Tennie C, Premo LS, Braun DR, McPherron SP. Early Stone Tools and Cultural Transmission: Resetting the Null Hypothesis. CURRENT ANTHROPOLOGY 2017. [DOI: 10.1086/693846] [Citation(s) in RCA: 64] [Impact Index Per Article: 9.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
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Persson T, Sauciuc GA, Madsen EA. Spontaneous cross-species imitation in interactions between chimpanzees and zoo visitors. Primates 2017; 59:19-29. [PMID: 28815382 PMCID: PMC5740201 DOI: 10.1007/s10329-017-0624-9] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2016] [Accepted: 08/05/2017] [Indexed: 11/24/2022]
Abstract
Imitation is a cornerstone of human development, serving both a cognitive function (e.g. in the acquisition and transmission of skills and knowledge) and a social–communicative function, whereby the imitation of familiar actions serves to maintain social interaction and promote prosociality. In nonhuman primates, this latter function is poorly understood, or even claimed to be absent. In this observational study, we documented interactions between chimpanzees and zoo visitors and found that the two species imitated each other at a similar rate, corresponding to almost 10% of all produced actions. Imitation appeared to accomplish a social–communicative function, as cross-species interactions that contained imitative actions lasted significantly longer than interactions without imitation. In both species, physical proximity promoted cross-species imitation. Overall, imitative precision was higher among visitors than among chimpanzees, but this difference vanished in proximity contexts, i.e. in the indoor environment. Four of five chimpanzees produced imitations; three of them exhibited comparable imitation rates, despite large individual differences in level of cross-species interactivity. We also found that chimpanzees evidenced imitation recognition, yet only when visitors imitated their actions (as opposed to postures). Imitation recognition was expressed by returned imitation in 36% of the cases, and all four imitating chimpanzees engaged in so-called imitative games. Previously regarded as unique to early human socialization, such games serve to maintain social engagement. The results presented here indicate that nonhuman apes exhibit spontaneous imitation that can accomplish a communicative function. The study raises a number of novel questions for imitation research and highlights the imitation of familiar behaviours as a relevant—yet thus far understudied—research topic.
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Affiliation(s)
- Tomas Persson
- Department of Philosophy, Cognitive Science, Lund University, Box 192, 221 00, Lund, Sweden
| | - Gabriela-Alina Sauciuc
- Department of Philosophy, Cognitive Science, Lund University, Box 192, 221 00, Lund, Sweden.
| | - Elainie Alenkær Madsen
- Department of Philosophy, Cognitive Science, Lund University, Box 192, 221 00, Lund, Sweden
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Cronin KA, Jacobson SL, Bonnie KE, Hopper LM. Studying primate cognition in a social setting to improve validity and welfare: a literature review highlighting successful approaches. PeerJ 2017; 5:e3649. [PMID: 28791199 PMCID: PMC5545107 DOI: 10.7717/peerj.3649] [Citation(s) in RCA: 45] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2016] [Accepted: 07/13/2017] [Indexed: 01/20/2023] Open
Abstract
BACKGROUND Studying animal cognition in a social setting is associated with practical and statistical challenges. However, conducting cognitive research without disturbing species-typical social groups can increase ecological validity, minimize distress, and improve animal welfare. Here, we review the existing literature on cognitive research run with primates in a social setting in order to determine how widespread such testing is and highlight approaches that may guide future research planning. SURVEY METHODOLOGY Using Google Scholar to search the terms "primate" "cognition" "experiment" and "social group," we conducted a systematic literature search covering 16 years (2000-2015 inclusive). We then conducted two supplemental searches within each journal that contained a publication meeting our criteria in the original search, using the terms "primate" and "playback" in one search and the terms "primate" "cognition" and "social group" in the second. The results were used to assess how frequently nonhuman primate cognition has been studied in a social setting (>3 individuals), to gain perspective on the species and topics that have been studied, and to extract successful approaches for social testing. RESULTS Our search revealed 248 unique publications in 43 journals encompassing 71 species. The absolute number of publications has increased over years, suggesting viable strategies for studying cognition in social settings. While a wide range of species were studied they were not equally represented, with 19% of the publications reporting data for chimpanzees. Field sites were the most common environment for experiments run in social groups of primates, accounting for more than half of the results. Approaches to mitigating the practical and statistical challenges were identified. DISCUSSION This analysis has revealed that the study of primate cognition in a social setting is increasing and taking place across a range of environments. This literature review calls attention to examples that may provide valuable models for researchers wishing to overcome potential practical and statistical challenges to studying cognition in a social setting, ultimately increasing validity and improving the welfare of the primates we study.
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Affiliation(s)
- Katherine A. Cronin
- Lester E. Fisher Center for the Study and Conservation of Apes, Lincoln Park Zoo, Chicago, IL, United States of America
| | - Sarah L. Jacobson
- Lester E. Fisher Center for the Study and Conservation of Apes, Lincoln Park Zoo, Chicago, IL, United States of America
| | - Kristin E. Bonnie
- Lester E. Fisher Center for the Study and Conservation of Apes, Lincoln Park Zoo, Chicago, IL, United States of America
- Department of Psychology, Beloit College, Beloit, WI, United States of America
| | - Lydia M. Hopper
- Lester E. Fisher Center for the Study and Conservation of Apes, Lincoln Park Zoo, Chicago, IL, United States of America
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Adaptive cultural transmission biases in children and nonhuman primates. Infant Behav Dev 2017; 48:45-53. [DOI: 10.1016/j.infbeh.2016.11.003] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2015] [Revised: 11/02/2016] [Accepted: 11/02/2016] [Indexed: 11/19/2022]
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Watson SK, Reamer LA, Mareno MC, Vale G, Harrison RA, Lambeth SP, Schapiro SJ, Whiten A. Socially transmitted diffusion of a novel behavior from subordinate chimpanzees. Am J Primatol 2017; 79. [PMID: 28171684 DOI: 10.1002/ajp.22642] [Citation(s) in RCA: 37] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2016] [Revised: 12/14/2016] [Accepted: 01/17/2017] [Indexed: 11/09/2022]
Abstract
Chimpanzees (Pan troglodytes) demonstrate much cultural diversity in the wild, yet a majority of novel behaviors do not become group-wide traditions. Since many such novel behaviors are introduced by low-ranking individuals, a bias toward copying dominant individuals ("rank-bias") has been proposed as an explanation for their limited diffusion. Previous experimental work showed that chimpanzees (Pan troglodytes) preferentially copy dominant over low-rank models. We investigated whether low ranking individuals may nevertheless successfully seed a beneficial behavior as a tradition if there are no "competing" models. In each of four captive groups, either a single high-rank (HR, n = 2) or a low-rank (LR, n = 2) chimpanzee model was trained on one method of opening a two-action puzzle-box, before demonstrating the trained method in a group context. This was followed by 8 hr of group-wide, open-access to the puzzle-box. Successful manipulations and observers of each manipulation were recorded. Barnard's exact tests showed that individuals in the LR groups used the seeded method as their first-choice option at significantly above chance levels, whereas those in the HR groups did not. Furthermore, individuals in the LR condition used the seeded method on their first attempt significantly more often than those in the HR condition. A network-based diffusion analysis (NBDA) revealed that the best supported statistical models were those in which social transmission occurred only in groups with subordinate models. Finally, we report an innovation by a subordinate individual that built cumulatively on existing methods of opening the puzzle-box and was subsequently copied by a dominant observer. These findings illustrate that chimpanzees are motivated to copy rewarding novel behaviors that are demonstrated by subordinate individuals and that, in some cases, social transmission may be constrained by high-rank demonstrators.
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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
| | - Lisa A Reamer
- National Centre for Chimpanzee Care, Michale E. Keeling Center for Comparative Medicine and Research, Department of Veterinary Sciences, UT MD Anderson Cancer Center, Bastrop, Texas
| | - Mary Catherine Mareno
- National Centre for Chimpanzee Care, Michale E. Keeling Center for Comparative Medicine and Research, Department of Veterinary Sciences, UT MD Anderson Cancer Center, Bastrop, Texas
| | - Gillian 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.,National Centre for Chimpanzee Care, Michale E. Keeling Center for Comparative Medicine and Research, Department of Veterinary Sciences, UT MD Anderson Cancer Center, Bastrop, Texas
| | - Rachel A Harrison
- Centre for Social Learning and Cognitive Evolution, and Scottish Primate Research Group, School of Psychology and Neuroscience, University of St Andrews, St Andrews, UK
| | - Susan P Lambeth
- National Centre for Chimpanzee Care, Michale E. Keeling Center for Comparative Medicine and Research, Department of Veterinary Sciences, UT MD Anderson Cancer Center, Bastrop, Texas
| | - Steven J Schapiro
- National Centre for Chimpanzee Care, Michale E. Keeling Center for Comparative Medicine and Research, Department of Veterinary Sciences, UT MD Anderson Cancer Center, Bastrop, Texas.,Department of Experimental Medicine, University of Copenhagen, Denmark
| | - 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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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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Abstract
Abstract
Humbug damselfish, Dascyllus aruanus, are a common coral reef fish that form stable social groups with size-based social hierarchies. Here we caught whole wild groups of damselfish and tested whether social groups tended to be comprised of animals that are more similar to one another in terms of their behavioural type, than expected by chance. First we found that individuals were repeatable in their level of activity and exploration, and that this was independent of both absolute size and within-group dominance rank, indicating that animals were behaviourally consistent. Secondly, despite the fact that individuals were tested independently, the behaviour of members of the same groups was significantly more similar than expected under a null model, suggesting that individual behaviour develops and is shaped by conformity to the behaviour of other group members. This is one of the first studies to demonstrate this group-level behavioural conformity in wild-caught groups.
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Affiliation(s)
- Alicia L.J. Burns
- a Animal Behaviour Lab, School of Life and Environmental Sciences, University of Sydney, Sydney, NSW, Australia
- bTaronga Conservation Society Australia, Bradleys Head Road, Mosman, NSW, Australia
| | - Timothy M. Schaerf
- a Animal Behaviour Lab, School of Life and Environmental Sciences, University of Sydney, Sydney, NSW, Australia
- cSchool of Science and Technology, University of New England, Armidale, NSW, Australia
| | - Ashley J.W. Ward
- a Animal Behaviour Lab, School of Life and Environmental Sciences, University of Sydney, Sydney, NSW, Australia
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Wrangham RW, Koops K, Machanda ZP, Worthington S, Bernard AB, Brazeau NF, Donovan R, Rosen J, Wilke C, Otali E, Muller MN. Distribution of a Chimpanzee Social Custom Is Explained by Matrilineal Relationship Rather Than Conformity. Curr Biol 2016; 26:3033-3037. [PMID: 27839974 DOI: 10.1016/j.cub.2016.09.005] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2016] [Revised: 08/08/2016] [Accepted: 09/02/2016] [Indexed: 10/20/2022]
Abstract
High-arm grooming is a form of chimpanzee grooming in which two individuals mutually groom while each raising one arm. Palm-to-palm clasping (PPC) is a distinct style of high-arm grooming in which the grooming partners clasp each other's raised palms. In wild communities, samples of at least 100 observed dyads grooming with raised hands showed PPC frequencies varying from <5% (M group, Mahale) to >30% dyads grooming (Kanyawara, Kibale), and in a large free-ranging sanctuary group, the frequency reached >80% dyads (group 1, Chimfunshi) [1, 2]. Because between-community differences in frequency of PPC apparently result from social learning, are stable across generations, and last for at least 9 years, they are thought to be cultural, but the mechanism of transmission is unknown [2]. Here, we examine factors responsible for individual variation in PPC frequency within a single wild community. We found that in the Kanyawara community (Kibale, Uganda), adults of both sexes varied widely in their PPC frequency (from <10% to >50%) and did not converge on a central group tendency. However, frequencies of PPC were highly consistent within matrilines, indicating that individuals maintained lifelong fidelity to the grooming style of their mothers. Matrilineal inheritance of socially learned behaviors has previously been reported for tool use in chimpanzees [3] and in the vocal and feeding behavior of cetaceans [4, 5]. Our evidence indicates that matrilineal inheritance can be sufficiently strong in nonhuman primates to account for long-term differences in community traditions.
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Affiliation(s)
- Richard W Wrangham
- Department of Human Evolutionary Biology, Harvard University, 11 Divinity Avenue, Cambridge, MA 02138, USA.
| | - Kathelijne Koops
- Department of Human Evolutionary Biology, Harvard University, 11 Divinity Avenue, Cambridge, MA 02138, USA; Anthropological Institute and Museum, University of Zurich, Winterthurerstrasse 190, 8057 Zürich, Switzerland
| | - Zarin P Machanda
- Department of Human Evolutionary Biology, Harvard University, 11 Divinity Avenue, Cambridge, MA 02138, USA; Department of Anthropology, Tufts University, 5 The Green, Medford, MA 02155, USA
| | - Steven Worthington
- Institute for Quantitative Social Science, Harvard University, 1737 Cambridge Street, Cambridge, MA 02138, USA
| | - Andrew B Bernard
- Department of Anthropology, University of Michigan, 101 West Hall, S. University Avenue, Ann Arbor, MI 48109, USA
| | - Nicholas F Brazeau
- Department of Epidemiology, Gillings School of Global Public Health, University of North Carolina, 1335 Dauer Drive, Chapel Hill, NC 27599, USA
| | - Ronan Donovan
- National Geographic Magazine, 1144 17(th) Street NW, Washington, DC 20036, USA
| | - Jeremiah Rosen
- Department of Human Evolutionary Biology, Harvard University, 11 Divinity Avenue, Cambridge, MA 02138, USA
| | - Claudia Wilke
- Department of Psychology, University of York, James Way, Heslington, York YO10 5DD, UK
| | - Emily Otali
- Kibale Chimpanzee Project, Makerere University Biological Field Station, Kamwenge Road, Fort Portal, Uganda
| | - Martin N Muller
- Department of Anthropology, University of New Mexico, Albuquerque, NM 87131, USA
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Acerbi A, van Leeuwen EJC, Haun DBM, Tennie C. Conformity cannot be identified based on population-level signatures. Sci Rep 2016; 6:36068. [PMID: 27796373 PMCID: PMC5086853 DOI: 10.1038/srep36068] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2016] [Accepted: 10/10/2016] [Indexed: 11/16/2022] Open
Abstract
Conformist transmission, defined as a disproportionate likelihood to copy the majority, is considered a potent mechanism underlying the emergence and stabilization of cultural diversity. However, ambiguity within and across disciplines remains as to how to identify conformist transmission empirically. In most studies, a population level outcome has been taken as the benchmark to evidence conformist transmission: a sigmoidal relation between individuals' probability to copy the majority and the proportional majority size. Using an individual-based model, we show that, under ecologically plausible conditions, this sigmoidal relation can also be detected without equipping individuals with a conformist bias. Situations in which individuals copy randomly from a fixed subset of demonstrators in the population, or in which they have a preference for one of the possible variants, yield similar sigmoidal patterns as a conformist bias would. Our findings warrant a revisiting of studies that base their conformist transmission conclusions solely on the sigmoidal curve. More generally, our results indicate that population level outcomes interpreted as conformist transmission could potentially be explained by other individual-level strategies, and that more empirical support is needed to prove the existence of an individual-level conformist bias in human and other animals.
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Affiliation(s)
- Alberto Acerbi
- Eindhoven University of Technology, School of Innovation Sciences, Eindhoven, 5600 MB, The Netherlands
| | - Edwin J. C. van Leeuwen
- University of St Andrews, School of Psychology & Neuroscience, Westburn Lane, St Andrews, Fife, KY16 9JP, United Kingdom
- Max Planck Institute for Psycholinguistics, Wundtlaan 1, 6525 XD Nijmegen, The Netherlands
| | - Daniel B. M. Haun
- University of Leipzig, Department of Early Child Development and Culture and Leipzig Research Center for Early Child Development, Jahnallee 59, Leipzig, 04109, Germany
| | - Claudio Tennie
- University of Birmingham, School of Psychology, Edgbaston, Birmingham, B15 2TT, United Kingdom
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Davis SJ, Vale GL, Schapiro SJ, Lambeth SP, Whiten A. Foundations of cumulative culture in apes: improved foraging efficiency through relinquishing and combining witnessed behaviours in chimpanzees (Pan troglodytes). Sci Rep 2016; 6:35953. [PMID: 27775061 PMCID: PMC5075880 DOI: 10.1038/srep35953] [Citation(s) in RCA: 50] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2016] [Accepted: 10/05/2016] [Indexed: 11/17/2022] Open
Abstract
A vital prerequisite for cumulative culture, a phenomenon often asserted to be unique to humans, is the ability to modify behaviour and flexibly switch to more productive or efficient alternatives. Here, we first established an inefficient solution to a foraging task in five captive chimpanzee groups (N = 19). Three groups subsequently witnessed a conspecific using an alternative, more efficient, solution. When participants could successfully forage with their established behaviours, most individuals did not switch to this more efficient technique; however, when their foraging method became substantially less efficient, nine chimpanzees with socially-acquired information (four of whom witnessed additional human demonstrations) relinquished their old behaviour in favour of the more efficient one. Only a single chimpanzee in control groups, who had not witnessed a knowledgeable model, discovered this. Individuals who switched were later able to combine components of their two learned techniques to produce a more efficient solution than their extensively used, original foraging method. These results suggest that, although chimpanzees show a considerable degree of conservatism, they also have an ability to combine independent behaviours to produce efficient compound action sequences; one of the foundational abilities (or candidate mechanisms) for human cumulative culture.
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Affiliation(s)
- Sarah J Davis
- Centre for Social learning and Cognitive Evolution, School of Psychology &Neuroscience, University of St Andrews, St Andrews, KY16 9JP, Scotland.,National Center for Chimpanzee Care, Department of Veterinary Sciences, Michale E. Keeling Center for Comparative Medicine and Research, the University of Texas MD Anderson Cancer Center, Bastrop, TX 78602, USA
| | - Gillian L Vale
- Centre for Social learning and Cognitive Evolution, School of Psychology &Neuroscience, University of St Andrews, St Andrews, KY16 9JP, Scotland.,National Center for Chimpanzee Care, Department of Veterinary Sciences, Michale E. Keeling Center for Comparative Medicine and Research, the University of Texas MD Anderson Cancer Center, Bastrop, TX 78602, USA
| | - Steven J Schapiro
- National Center for Chimpanzee Care, Department of Veterinary Sciences, Michale E. Keeling Center for Comparative Medicine and Research, the University of Texas MD Anderson Cancer Center, Bastrop, TX 78602, USA
| | - Susan P Lambeth
- National Center for Chimpanzee Care, Department of Veterinary Sciences, Michale E. Keeling Center for Comparative Medicine and Research, the University of Texas MD Anderson Cancer Center, Bastrop, TX 78602, USA
| | - Andrew Whiten
- Centre for Social learning and Cognitive Evolution, School of Psychology &Neuroscience, University of St Andrews, St Andrews, KY16 9JP, Scotland
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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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Luncz LV, Wittig RM, Boesch C. Primate archaeology reveals cultural transmission in wild chimpanzees (Pan troglodytes verus). Philos Trans R Soc Lond B Biol Sci 2016; 370:rstb.2014.0348. [PMID: 26483527 DOI: 10.1098/rstb.2014.0348] [Citation(s) in RCA: 48] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Recovering evidence of past human activities enables us to recreate behaviour where direct observations are missing. Here, we apply archaeological methods to further investigate cultural transmission processes in percussive tool use among neighbouring chimpanzee communities in the Taï National Park, Côte d'Ivoire, West Africa. Differences in the selection of nut-cracking tools between neighbouring groups are maintained over time, despite frequent female transfer, which leads to persistent cultural diversity between chimpanzee groups. Through the recovery of used tools in the suggested natal territory of immigrants, we have been able to reconstruct the tool material selection of females prior to migration. In combination with direct observations of tool selection of local residents and immigrants after migration, we uncovered temporal changes in tool selection for immigrating females. After controlling for ecological differences between territories of immigrants and residents our data suggest that immigrants abandoned their previous tool preference and adopted the pattern of their new community, despite previous personal proficiency of the same foraging task. Our study adds to the growing body of knowledge on the importance of conformist tendencies in animals.
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Affiliation(s)
- Lydia V Luncz
- Department of Primatology, Max Planck Institute for Evolutionary Anthropology, 04103 Leipzig, Germany Research Laboratory for Archaeology and the History of Art, University of Oxford, Oxford OX1 3QY, UK
| | - Roman M Wittig
- Department of Primatology, Max Planck Institute for Evolutionary Anthropology, 04103 Leipzig, Germany Taï Chimpanzee Project, Centre Suisse de Recherches Scientifiques, BP 1303, Abidjan 01, Côte d'Ivoire, West Africa
| | - Christophe Boesch
- Department of Primatology, Max Planck Institute for Evolutionary Anthropology, 04103 Leipzig, Germany
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45
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46
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Aplin LM, Farine DR, Morand-Ferron J, Cockburn A, Thornton A, Sheldon BC. Counting conformity: evaluating the units of information in frequency-dependent social learning. Anim Behav 2015. [DOI: 10.1016/j.anbehav.2015.09.015] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
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47
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Hopper LM, Kurtycz LM, Ross SR, Bonnie KE. Captive chimpanzee foraging in a social setting: a test of problem solving, flexibility, and spatial discounting. PeerJ 2015; 3:e833. [PMID: 25802805 PMCID: PMC4369338 DOI: 10.7717/peerj.833] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/02/2015] [Accepted: 02/19/2015] [Indexed: 11/24/2022] Open
Abstract
In the wild, primates are selective over the routes that they take when foraging and seek out preferred or ephemeral food. Given this, we tested how a group of captive chimpanzees weighed the relative benefits and costs of foraging for food in their environment when a less-preferred food could be obtained with less effort than a more-preferred food. In this study, a social group of six zoo-housed chimpanzees (Pan troglodytes) could collect PVC tokens and exchange them with researchers for food rewards at one of two locations. Food preference tests had revealed that, for these chimpanzees, grapes were a highly-preferred food while carrot pieces were a less-preferred food. The chimpanzees were tested in three phases, each comprised of 30 thirty-minute sessions. In phases 1 and 3, if the chimpanzees exchanged a token at the location they collected them they received a carrot piece (no travel) or they could travel ≥10 m to exchange tokens for grapes at a second location. In phase 2, the chimpanzees had to travel for both rewards (≥10 m for carrot pieces, ≥15 m for grapes). The chimpanzees learned how to exchange tokens for food rewards, but there was individual variation in the time it took for them to make their first exchange and to discover the different exchange locations. Once all the chimpanzees were proficient at exchanging tokens, they exchanged more tokens for grapes (phase 3). However, when travel was required for both rewards (phase 2), the chimpanzees were less likely to work for either reward. Aside from the alpha male, all chimpanzees exchanged tokens for both reward types, demonstrating their ability to explore the available options. Contrary to our predictions, low-ranked individuals made more exchanges than high-ranked individuals, most likely because, in this protocol, chimpanzees could not monopolize the tokens or access to exchange locations. Although the chimpanzees showed a preference for exchanging tokens for their more-preferred food, they appeared to develop strategies to reduce the cost associated with obtaining the grapes, including scrounging rewards and tokens from group mates and carrying more than one token when travelling to the farther exchange location. By testing the chimpanzees in their social group we were able to tease apart the social and individual influences on their decision making and the interplay with the physical demands of the task, which revealed that the chimpanzees were willing to travel farther for better.
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Affiliation(s)
- Lydia M. Hopper
- Lester E. Fisher Center for the Study & Conservation of Apes, Lincoln Park Zoo, Chicago, IL, USA
| | - Laura M. Kurtycz
- Lester E. Fisher Center for the Study & Conservation of Apes, Lincoln Park Zoo, Chicago, IL, USA
| | - Stephen R. Ross
- Lester E. Fisher Center for the Study & Conservation of Apes, Lincoln Park Zoo, Chicago, IL, USA
| | - Kristin E. Bonnie
- Lester E. Fisher Center for the Study & Conservation of Apes, Lincoln Park Zoo, Chicago, IL, USA
- Department of Psychology, Beloit College, Beloit, WI, USA
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48
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Gruber T, Zuberbühler K, Clément F, van Schaik C. Apes have culture but may not know that they do. Front Psychol 2015; 6:91. [PMID: 25705199 PMCID: PMC4319388 DOI: 10.3389/fpsyg.2015.00091] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2014] [Accepted: 01/16/2015] [Indexed: 11/13/2022] Open
Abstract
There is good evidence that some ape behaviors can be transmitted socially and that this can lead to group-specific traditions. However, many consider animal traditions, including those in great apes, to be fundamentally different from human cultures, largely because of lack of evidence for cumulative processes and normative conformity, but perhaps also because current research on ape culture is usually restricted to behavioral comparisons. Here, we propose to analyze ape culture not only at the surface behavioral level but also at the underlying cognitive level. To this end, we integrate empirical findings in apes with theoretical frameworks developed in developmental psychology regarding the representation of tools and the development of metarepresentational abilities, to characterize the differences between ape and human cultures at the cognitive level. Current data are consistent with the notion of apes possessing mental representations of tools that can be accessed through re-representations: apes may reorganize their knowledge of tools in the form of categories or functional schemes. However, we find no evidence for metarepresentations of cultural knowledge: apes may not understand that they or others hold beliefs about their cultures. The resulting Jourdain Hypothesis, based on Molière’s character, argues that apes express their cultures without knowing that they are cultural beings because of cognitive limitations in their ability to represent knowledge, a determining feature of modern human cultures, allowing representing and modifying the current norms of the group. Differences in metarepresentational processes may thus explain fundamental differences between human and other animals’ cultures, notably limitations in cumulative behavior and normative conformity. Future empirical work should focus on how animals mentally represent their cultural knowledge to conclusively determine the ways by which humans are unique in their cultural behavior.
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Affiliation(s)
- Thibaud Gruber
- Department of Comparative Cognition, Institute of Biology, University of Neuchâtel Neuchâtel, Switzerland
| | - Klaus Zuberbühler
- Department of Comparative Cognition, Institute of Biology, University of Neuchâtel Neuchâtel, Switzerland ; School of Psychology and Neuroscience, University of St Andrews St Andrews, UK
| | - Fabrice Clément
- Cognitive Science Centre, University of Neuchâtel Neuchâtel, Switzerland
| | - Carel van Schaik
- Anthropological Institute and Museum, University of Zürich Zürich, Switzerland
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Claidière N, Whiten A, Mareno MC, Messer EJE, Brosnan SF, Hopper LM, Lambeth SP, Schapiro SJ, McGuigan N. Selective and contagious prosocial resource donation in capuchin monkeys, chimpanzees and humans. Sci Rep 2015; 5:7631. [PMID: 25559658 PMCID: PMC4284509 DOI: 10.1038/srep07631] [Citation(s) in RCA: 39] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2014] [Accepted: 11/20/2014] [Indexed: 01/13/2023] Open
Abstract
Prosocial acts benefitting others are widespread amongst humans. By contrast, chimpanzees have failed to demonstrate such a disposition in several studies, leading some authors to conclude that the forms of prosociality studied evolved in humans since our common ancestry. However, similar prosocial behavior has since been documented in other primates, such as capuchin monkeys. Here, applying the same methodology to humans, chimpanzees, and capuchins, we provide evidence that all three species will display prosocial behavior, but only in certain conditions. Fundamental forms of prosociality were age-dependent in children, conditional on self-beneficial resource distributions even at age seven, and conditional on social or resource configurations in chimpanzees and capuchins. We provide the first evidence that experience of conspecific companions' prosocial behavior facilitates prosocial behavior in children and chimpanzees. Prosocial actions were manifested in all three species following rules of contingency that may reflect strategically adaptive responses.
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Affiliation(s)
- Nicolas Claidière
- Centre for Social Learning and Cognitive Evolution, School of Psychology & Neuroscience, University of St. Andrews, St. Andrews, KY16 9JP, UK
| | - Andrew Whiten
- Centre for Social Learning and Cognitive Evolution, School of Psychology & Neuroscience, University of St. Andrews, St. Andrews, KY16 9JP, UK
| | - Mary C. Mareno
- Michale E. Keeling Center for Comparative Medicine and Research, UT MD Anderson Cancer Center, Bastrop, TX, USA
| | - Emily J. E. Messer
- Centre for Social Learning and Cognitive Evolution, School of Psychology & Neuroscience, University of St. Andrews, St. Andrews, KY16 9JP, UK
| | - Sarah F. Brosnan
- Michale E. Keeling Center for Comparative Medicine and Research, UT MD Anderson Cancer Center, Bastrop, TX, USA
- Department of Psychology and Language Research Center, Georgia State University, PO Box 5010, Atlanta, GA 30302-5010, USA
| | - Lydia M. Hopper
- Michale E. Keeling Center for Comparative Medicine and Research, UT MD Anderson Cancer Center, Bastrop, TX, USA
- Department of Psychology and Language Research Center, Georgia State University, PO Box 5010, Atlanta, GA 30302-5010, USA
- Lester E. Fisher Center for the Study & Conservation of Apes, Lincoln Park Zoo, Chicago, IL 60614, USA
| | - Susan P. Lambeth
- Michale E. Keeling Center for Comparative Medicine and Research, UT MD Anderson Cancer Center, Bastrop, TX, USA
| | - Steven J. Schapiro
- 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
| | - Nicola McGuigan
- School of Life Sciences, Heriot Watt University, Edinburgh, EH14 4AS, UK
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50
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Kendal R, Hopper LM, Whiten A, Brosnan SF, Lambeth SP, Schapiro SJ, Hoppitt W. Chimpanzees copy dominant and knowledgeable individuals: implications for cultural diversity. EVOL HUM BEHAV 2015; 36:65-72. [PMID: 27053916 PMCID: PMC4820294 DOI: 10.1016/j.evolhumbehav.2014.09.002] [Citation(s) in RCA: 128] [Impact Index Per Article: 14.2] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Evolutionary theory predicts that natural selection will fashion cognitive biases to guide when, and from whom, individuals acquire social information, but the precise nature of these biases, especially in ecologically valid group contexts, remains unknown. We exposed four captive groups of chimpanzees (Pan troglodytes) to a novel extractive foraging device and, by fitting statistical models, isolated four simultaneously operating transmission biases. These include biases to copy (i) higher-ranking and (ii) expert individuals, and to copy others when (iii) uncertain or (iv) of low rank. High-ranking individuals were relatively un-strategic in their use of acquired knowledge, which, combined with the bias for others to observe them, may explain reports that high innovation rates (in juveniles and subordinates) do not generate a correspondingly high frequency of traditions in chimpanzees. Given the typically low rank of immigrants in chimpanzees, a 'copying dominants' bias may contribute to the observed maintenance of distinct cultural repertoires in neighboring communities despite sharing similar ecology and knowledgeable migrants. Thus, a copying dominants strategy may, as often proposed for conformist transmission, and perhaps in concert with it, restrict the accumulation of traditions within chimpanzee communities whilst maintaining cultural diversity.
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Affiliation(s)
- Rachel Kendal
- Centre for the Coevolution of Biology and Culture, Anthropology Department, Durham University, UK
| | - Lydia M. Hopper
- Centre for the Coevolution of Biology and Culture, Anthropology Department, Durham University, UK
- Centre for Social Learning and Cognitive Evolution, School of Psychology and Neuroscience, University of St. Andrews, UK
- Michale E. Keeling Center for Comparative Medicine and Research, UT MD Anderson Cancer Center, USA
- Lester E. Fisher Center for the Study & Conservation of Apes, Lincoln Park Zoo, USA
| | - Andrew Whiten
- Centre for Social Learning and Cognitive Evolution, School of Psychology and Neuroscience, University of St. Andrews, UK
| | - Sarah F. Brosnan
- Michale E. Keeling Center for Comparative Medicine and Research, UT MD Anderson Cancer Center, USA
- Language Research Center, GA State University, USA
- Department of Psychology & Neuroscience Institute, GA State University, USA
| | - Susan P. Lambeth
- Michale E. Keeling Center for Comparative Medicine and Research, UT MD Anderson Cancer Center, USA
| | - Steven J. Schapiro
- Michale E. Keeling Center for Comparative Medicine and Research, UT MD Anderson Cancer Center, USA
- Department of Experimental Medicine, University of Copenhagen, Denmark
| | - Will Hoppitt
- Centre for Social Learning and Cognitive Evolution, School of Biology, University of St. Andrews, UK
- Department of Life Sciences, Anglia Ruskin University, UK
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