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Author (up) Bonnie, K.E.; de Waal, F.B.M.
Title Affiliation promotes the transmission of a social custom: handclasp grooming among captive chimpanzees Type Journal Article
Year 2006 Publication Primates Abbreviated Journal Primates
Volume 47 Issue 1 Pages 27-34
Keywords Animals; Animals, Zoo/*physiology; Behavior, Animal/*physiology; *Cultural Evolution; Grooming/*physiology; Observation; Pan troglodytes/*physiology; *Social Behavior
Abstract Handclasp grooming is a unique social custom, known to occur regularly among some, but not all populations of chimpanzees (Pan troglodytes). As with other cultural behaviors, it is assumed that this distinctive grooming posture is learned socially by one individual from another. However, statistical comparisons among factors thought to influence how a behavior spreads within a group have never, to our knowledge, been conducted. In the present study, the origination and spread of handclasp grooming in a group of captive chimpanzees was followed throughout more than 1,500 h of observation over a period of 12 years. We report on the frequency, bout duration, and number and demography of performers throughout the study period, and compare these findings to those reported for wild populations. We predicted that dyads with strong affiliative ties, measured by time spent in proximity to and grooming one another, were likely to develop a handclasp grooming partnership during the study period. A quadratic assignment procedure was used to compare correlations among observed frequencies of grooming and proximity with handclasp grooming in all possible dyads within the group. As predicted, the formation of new handclasp grooming dyads was positively correlated with the rate of overall grooming and proximity within a dyad. In addition, in nearly all dyads formed, at least one individual had been previously observed to handclasp groom. We concluded that affiliation and individual experience determines the transmission of handclasp grooming among captive chimpanzees.
Address Department of Psychology, Emory University, and Living Links Center, Yerkes National Primate Research Center, GA 30329, USA. kebonni@emory.edu
Corporate Author Thesis
Publisher Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0032-8332 ISBN Medium
Area Expedition Conference
Notes PMID:16142425 Approved no
Call Number refbase @ user @ Serial 161
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Author (up) Bonnie, K.E.; Horner, V.; Whiten, A.; de Waal, F.B.M.
Title Spread of arbitrary conventions among chimpanzees: a controlled experiment Type Journal Article
Year 2007 Publication Proceedings. Biological sciences / The Royal Society Abbreviated Journal Proc Biol Sci
Volume 274 Issue 1608 Pages 367-372
Keywords
Abstract Wild chimpanzees (Pan troglodytes) have a rich cultural repertoire--traditions common in some communities are not present in others. The majority of reports describe functional, material traditions, such as tool use. Arbitrary conventions have received far less attention. In the same way that observations of material culture in wild apes led to experiments to confirm social transmission and identify underlying learning mechanisms, experiments investigating how arbitrary habits or conventions arise and spread within a group are also required. The few relevant experimental studies reported thus far have relied on cross-species (i.e. human-ape) interaction offering limited ecological validity, and no study has successfully generated a tradition not involving tool use in an established group. We seeded one of two rewarded alternative endpoints to a complex sequence of behaviour in each of two chimpanzee groups. Each sequence spread in the group in which it was seeded, with many individuals unambiguously adopting the sequence demonstrated by a group member. In one group, the alternative sequence was discovered by a low ranking female, but was not learned by others. Since the action-sequences lacked meaning before the experiment and had no logical connection with reward, chimpanzees must have extracted both the form and benefits of these sequences through observation of others.
Address Living Links, Yerkes National Primate Research Center, Atlanta, GA 30329, USA. kebonni@emory.edu
Corporate Author Thesis
Publisher Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0962-8452 ISBN Medium
Area Expedition Conference
Notes PMID:17164200 Approved no
Call Number refbase @ user @ Serial 157
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Author (up) Brosnan, S.F.; de Waal, F.B.M.
Title Responses to a simple barter task in chimpanzees, Pan troglodytes Type Journal Article
Year 2005 Publication Primates Abbreviated Journal Primates
Volume 46 Issue 3 Pages 173-182
Keywords Analysis of Variance; Animals; Choice Behavior/*physiology; Conditioning (Psychology)/physiology; Learning/*physiology; Pan troglodytes/*physiology; Reward; Sex Factors; *Social Behavior; *Token Economy
Abstract Chimpanzees (Pan troglodytes) frequently participate in social exchange involving multiple goods and services of variable value, yet they have not been tested in a formalized situation to see whether they can barter using multiple tokens and rewards. We set up a simple barter economy with two tokens and two associated rewards and tested chimpanzees on their ability to obtain rewards by returning the matching token in situations in which their access to tokens was unlimited or limited. Chimpanzees easily learned to associate value with the tokens, as expected, and did barter, but followed a simple strategy of favoring the higher-value token, regardless of the reward proffered, instead of a more complex but more effective strategy of returning the token that matched the reward. This response is similar to that shown by capuchin monkeys in our previous study. We speculate that this response, while not ideal, may be sufficient to allow for stability of the social exchange system in these primates, and that the importance of social barter to both species may have led to this convergence of strategies.
Address Living Links, Yerkes National Primate Research Center, Atlanta, GA 30322, USA. sbrosna@emory.edu
Corporate Author Thesis
Publisher Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0032-8332 ISBN Medium
Area Expedition Conference
Notes PMID:15824938 Approved no
Call Number refbase @ user @ Serial 167
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Author (up) Brosnan, S.F.; de Waal, F.B.M.
Title A concept of value during experimental exchange in brown capuchin monkeys, Cebus apella Type Journal Article
Year 2004 Publication Folia primatologica; international journal of primatology Abbreviated Journal Folia Primatol (Basel)
Volume 75 Issue 5 Pages 317-330
Keywords Animals; Cebus/*psychology; *Choice Behavior; Female; Food Preferences; *Learning; Male; Sex Factors; Statistics, Nonparametric; *Token Economy; Video Recording
Abstract We evaluated the response of brown capuchin monkeys to two differentially valued tokens in an experimental exchange situation akin to a simple barter. Monkeys were given a series of three tests to evaluate their ability to associate tokens with food, then their responses were examined in a barter situation in which tokens were either limited or unlimited. Capuchins did not perform barter in the typical sense, returning the tokens which were associated with the reward. However, females, but not males, showed a different response, preferring the higher-value token. This may indicate that they learned to prefer one token over the other rather than to associate the tokens with their specific rewards. This sex difference parallels previous findings of greater reciprocity in female brown capuchins than in males.
Address Living Links Center, Emory University, Yerkes National Primate Research Center, 954 N. Gatewood Drive, Atlanta, GA 30329, USA. sbrosna@emory.edu
Corporate Author Thesis
Publisher Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0015-5713 ISBN Medium
Area Expedition Conference
Notes PMID:15486443 Approved no
Call Number refbase @ user @ Serial 170
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Author (up) Brosnan, S.F.; de Waal, F.B.M.
Title Socially learned preferences for differentially rewarded tokens in the brown capuchin monkey (Cebus apella) Type Journal Article
Year 2004 Publication Journal of comparative psychology (Washington, D.C. : 1983) Abbreviated Journal J Comp Psychol
Volume 118 Issue 2 Pages 133-139
Keywords Animals; Behavior, Animal; Cebus; *Choice Behavior; Female; *Learning; Male; *Reward; *Social Behavior
Abstract Social learning is assumed to underlie traditions, yet evidence indicating social learning in capuchin monkeys (Cebus apella), which exhibit traditions, is sparse. The authors tested capuchins for their ability to learn the value of novel tokens using a previously familiar token-exchange economy. Capuchins change their preferences in favor of a token worth a high-value food reward after watching a conspecific model exchange 2 differentially rewarded tokens, yet they fail to develop a similar preference after watching tokens paired with foods in the absence of a conspecific model. They also fail to learn that the value of familiar tokens has changed. Information about token value is available in all situations, but capuchins seem to pay more attention in a social situation involving novel tokens.
Address Living Links Center, Yerkes National Primate Research Center, and Graduate Division of Biological and Biomedical Sciences, Emory University, Atlanta, GA 30329, USA. sbrosna@emory.edu
Corporate Author Thesis
Publisher Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0735-7036 ISBN Medium
Area Expedition Conference
Notes PMID:15250800 Approved no
Call Number refbase @ user @ Serial 173
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Author (up) Brosnan, S.F.; De Waal, F.B.M.
Title Monkeys reject unequal pay Type Journal Article
Year 2003 Publication Nature Abbreviated Journal Nature
Volume 425 Issue 6955 Pages 297-299
Keywords Aging; Animals; Cebus/*psychology; Choice Behavior; *Cooperative Behavior; Female; Male; *Reward; Social Justice
Abstract During the evolution of cooperation it may have become critical for individuals to compare their own efforts and pay-offs with those of others. Negative reactions may occur when expectations are violated. One theory proposes that aversion to inequity can explain human cooperation within the bounds of the rational choice model, and may in fact be more inclusive than previous explanations. Although there exists substantial cultural variation in its particulars, this 'sense of fairness' is probably a human universal that has been shown to prevail in a wide variety of circumstances. However, we are not the only cooperative animals, hence inequity aversion may not be uniquely human. Many highly cooperative nonhuman species seem guided by a set of expectations about the outcome of cooperation and the division of resources. Here we demonstrate that a nonhuman primate, the brown capuchin monkey (Cebus apella), responds negatively to unequal reward distribution in exchanges with a human experimenter. Monkeys refused to participate if they witnessed a conspecific obtain a more attractive reward for equal effort, an effect amplified if the partner received such a reward without any effort at all. These reactions support an early evolutionary origin of inequity aversion.
Address Living Links, Yerkes National Primate Research Center, Emory University, Atlanta, Georgia 30329, USA. sbrosna@emory.edu
Corporate Author Thesis
Publisher Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1476-4687 ISBN Medium
Area Expedition Conference
Notes PMID:13679918 Approved no
Call Number refbase @ user @ Serial 179
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Author (up) Brosnan, S.F.; Freeman, C.; De Waal, F.B.M.
Title Partner's behavior, not reward distribution, determines success in an unequal cooperative task in capuchin monkeys Type Journal Article
Year 2006 Publication American journal of primatology Abbreviated Journal Am. J. Primatol.
Volume 68 Issue 7 Pages 713-724
Keywords Animals; Behavior, Animal/*physiology; Cebus/*physiology; *Cooperative Behavior; Female; Food Preferences/physiology; Male; *Reward
Abstract It was recently demonstrated that capuchin monkeys notice and respond to distributional inequity, a trait that has been proposed to support the evolution of cooperation in the human species. However, it is unknown how capuchins react to inequitable rewards in an unrestricted cooperative paradigm in which they may freely choose both whether to participate and, within the bounds of their partner's behavior, which reward they will receive for their participation. We tested capuchin monkeys with such a design, using a cooperative barpull, which has been used with great success in the past. Contrary to our expectations, the equity of the reward distribution did not affect success or pulling behavior. However, the behavior of the partner in an unequal situation did affect overall success rates: pairs that had a tendency to alternate which individual received the higher-value food in unequal reward situations were more than twice as successful in obtaining rewards than pairs in which one individual dominated the higher-value food. This ability to equitably distribute rewards in inherently biased cooperative situations has profound implications for activities such as group hunts, in which multiple individuals work together for a single, monopolizable reward.
Address Living Links Center, Yerkes National Primate Research Center, Emory University, Atlanta, Georgia, USA. sbrosna@emory.edu
Corporate Author Thesis
Publisher Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0275-2565 ISBN Medium
Area Expedition Conference
Notes PMID:16786518 Approved no
Call Number refbase @ user @ Serial 160
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Author (up) Brosnan, S.F.; Schiff, H.C.; de Waal, F.B.M.
Title Tolerance for inequity may increase with social closeness in chimpanzees Type Journal Article
Year 2005 Publication Proceedings. Biological sciences / The Royal Society Abbreviated Journal Proc Biol Sci
Volume 272 Issue 1560 Pages 253-258
Keywords Analysis of Variance; Animals; *Attitude; Group Processes; Pan troglodytes/*psychology; Reward; *Social Behavior; Socioeconomic Factors
Abstract Economic decision-making depends on our social environment. Humans tend to respond differently to inequity in close relationships, yet we know little about the potential for such variation in other species. We examine responses to inequity in several groups of chimpanzees (Pan troglodytes) in a paradigm similar to that used previously in capuchin monkeys (Cebus apella). We demonstrate that, like capuchin monkeys, chimpanzees show a response to inequity of rewards that is based upon the partner receiving the reward rather than the presence of the reward alone. However, we also found a great amount of variation between groups tested, indicating that chimpanzees, like people, respond to inequity in a variable manner, which we speculate could be caused by such variables as group size, the social closeness of the group (as reflected in length of time that the group has been together) and group-specific traditions.
Address Yerkes National Primate Research Center, Emory University, 954 North Gatewood Drive, Atlanta, GA 30329, USA. sbrosna@emory.edu
Corporate Author Thesis
Publisher Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0962-8452 ISBN Medium
Area Expedition Conference
Notes PMID:15705549 Approved no
Call Number refbase @ user @ Serial 169
Permanent link to this record
 
 
Author (up) Call, J.; Aureli, F.; de Waal, F.B.M.
Title Postconflict third-party affiliation in stumptailed macaques Type Journal Article
Year 2002 Publication Animal Behaviour. Abbreviated Journal Anim. Behav.
Volume 63 Issue 2 Pages 209-216
Keywords
Abstract Stumptailed macaques, Macaca arctoides, are characterized by high levels of postconflict affiliative contacts between opponents. We investigated the occurrence of postconflict affiliative contacts between opponents and third parties that were not involved in the original conflict. We collected 10-min focal observations during postconflict and control periods in which we recorded all aggressive and affiliative behaviours between opponents and third parties. We distinguished three types of third parties depending on the relationship with the focal animal: own kin, opponent's kin and individuals unrelated to both opponents. We analysed the interactions with third parties separately, while distinguishing two classes of affiliative behaviours: (1) allogrooming and contact sitting and (2) sociosexual behaviours (e.g. genital inspection). The macaques showed differences between postconflict and control periods in their affiliative contacts with third parties. Aggressors received more postconflict grooming and contact sitting from their opponents' kin, received more sociosexual behaviour from their own kin and unrelated individuals, and directed more sociosexual behaviour to unrelated individuals. Victims received and directed less postconflict grooming from and towards their own kin. They received more postconflict sociosexual behaviour from all partners except their own kin and directed more sociosexual behaviour to all partners except the opponent's kin. This study establishes the occurrence of multiple postconflict triadic affiliation in stumptailed macaques, and is the first to show that victims receive contacts from third parties in a cercopithecine species, a behaviour previously described only in chimpanzees. It also highlights the importance of analysing the different affiliative behaviours separately in postconflict situations. Otherwise, many of the patterns we report, especially those involving victims, would have been missed.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN ISBN Medium
Area Expedition Conference
Notes Approved no
Call Number refbase @ user @ Serial 304
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Author (up) de Waal, F.B.M.
Title Putting the Altruism Back into Altruism: The Evolution of Empathy Type Journal Article
Year 2008 Publication Annual Review of Psychology Abbreviated Journal Annu Rev Psychol
Volume 59 Issue 1 Pages 279-300
Keywords
Abstract Evolutionary theory postulates that altruistic behavior evolved for the return-benefits it bears the performer. For return-benefits to play a motivational role, however, they need to be experienced by the organism. Motivational analyses should restrict themselves, therefore, to the altruistic impulse and its knowable consequences. Empathy is an ideal candidate mechanism to underlie so-called directed altruism, i.e., altruism in response to anothers's pain, need, or distress. Evidence is accumulating that this mechanism is phylogenetically ancient, probably as old as mammals and birds. Perception of the emotional state of another automatically activates shared representations causing a matching emotional state in the observer. With increasing cognition, state-matching evolved into more complex forms, including concern for the other and perspective-taking. Empathy-induced altruism derives its strength from the emotional stake it offers the self in the other's welfare. The dynamics of the empathy mechanism agree with predictions from kin selection and reciprocal altruism theory.
Address
Corporate Author Thesis
Publisher Annual Reviews Place of Publication Editor
Language Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0066-4308 ISBN Medium
Area Expedition Conference
Notes doi: 10.1146/annurev.psych.59.103006.093625 Approved no
Call Number Equine Behaviour @ team @ Serial 5058
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