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Chimpanzees Help Each Other upon Request

Yamamoto, Shinya, Humle, Tatyana, Tanaka, Masayuki (2009) Chimpanzees Help Each Other upon Request. PLoS ONE, 4 (10). e7416. ISSN 1932-6203. (doi:10.1371/journal.pone.0007416) (KAR id:31492)

Language: English

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Background: The evolution of altruism has been explained mainly from ultimate perspectives. However, it remains to be investigated from a proximate point of view how and in which situations such social propensity is achieved. We investigated chimpanzees' targeted helping in a tool transfer paradigm, and discuss the similarities and differences in altruism between humans and chimpanzees. Previously it has been suggested that chimpanzees help human experimenters by retrieving an object which the experimenter is trying to reach. In the present study, we investigated the importance of communicative interactions between chimpanzees themselves and the influence of conspecific partner's request on chimpanzees' targeted helping. Methodology/Principal Findings: We presented two tool-use situations ( a stick-use situation and a straw-use situation) in two adjacent booths, and supplied non-corresponding tools to paired chimpanzees in the two booths. For example, a chimpanzee in the stick-use situation was supplied with a straw, and the partner in the straw-use situation possessed a stick. Spontaneous tool transfer was observed between paired chimpanzees. The tool transfer events occurred predominantly following recipients' request. Even without any hope of reciprocation from the partner, the chimpanzees continued to help the partner as long as the partner required help. Conclusions/Significance: These results provide further evidence for altruistic helping in chimpanzees in the absence of direct personal gain or even immediate reciprocation. Our findings additionally highlight the importance of request as a proximate mechanism motivating prosocial behavior in chimpanzees whether between kin or non-kin individuals and the possible confounding effect of dominance on the symmetry of such interactions. Finally, in contrast to humans, our study suggests that chimpanzees rarely perform acts of voluntary altruism. Voluntary altruism in chimpanzees is not necessarily prompted by simple observation of another's struggle to attain a goal and therefore an accurate understanding of others' desires in the absence of communicative signals.

Item Type: Article
DOI/Identification number: 10.1371/journal.pone.0007416
Uncontrolled keywords: altruism, animal behavior, animal experiment, article, chimpanzee, controlled study, female, help seeking behavior, interpersonal communication, motivation, nonhuman, social behavior, social interaction, task performance, animal, animal communication, cooperation, human relation, male, Pan troglodytes, perception, physiology, psychological aspect, social environment, tool use, Pan, Altruism, Animal Communication, Animals, Behavior, Animal, Cooperative Behavior, Female, Interpersonal Relations, Male, Pan troglodytes, Social Behavior, Social Environment, Social Perception, Tool Use Behavior
Subjects: B Philosophy. Psychology. Religion > BF Psychology
G Geography. Anthropology. Recreation > GN Anthropology
Q Science > QL Zoology
Divisions: Divisions > Division of Human and Social Sciences > School of Anthropology and Conservation
Divisions > Division of Human and Social Sciences > School of Anthropology and Conservation > DICE (Durrell Institute of Conservation and Ecology)
Depositing User: Tatyana Humle
Date Deposited: 10 Oct 2012 14:29 UTC
Last Modified: 16 Feb 2021 12:42 UTC
Resource URI: (The current URI for this page, for reference purposes)
Humle, Tatyana:
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