Chimpanzees use social information to acquire a skill they fail to innovate

E.J.C.v.L. was funded by the European Union under European Research Council Starting Grant no. 101042961—CULT_ORIGINS.Cumulative cultural evolution has been claimed to be a uniquely human phenomenon pivotal to the biological success of our species. One plausible condition for cumulative cultural evolution to emerge is individuals’ ability to use social learning to acquire know-how that they cannot easily innovate by themselves. It has been suggested that chimpanzees may be capable of such know-how social learning, but this assertion remains largely untested. Here we show that chimpanzees use social learning to acquire a skill that they failed to independently innovate. By teaching chimpanzees how to solve a sequential task (one chimpanzee in each of the two tested groups, n = 66) and using network-based diffusion analysis, we found that 14 naive chimpanzees learned to operate a puzzle box that they failed to operate during the preceding three months of exposure to all necessary materials. In conjunction, we present evidence for the hypothesis that social learning in chimpanzees is necessary and sufficient to acquire a new, complex skill after the initial innovation.Peer reviewe

Evolution of Humanity

English Translation of the Original Essay by Kinji Imanishi. Including Commentaries by Contemporary ScholarsIn 1952, Kinji Imanishi wrote a thought-provoking essay on the nature of animal societies. In this essay, he applied the concept of human culture (which he referred to as Karuchua) to nonhuman animals by giving different taxa a voice in a fable-like conversation, thereby aptly transcending speciesism. While thoroughly inspiring for scholars who have mastered the Japanese language, the essay was only known to non-Japanese-speakers by its English abstract. Here, we unveil the rest of the essay for the English-speaking community. Furthermore, to contextualize the seminal text, we asked contemporary scholars working in the field of (animal) culture to comment on the essay in a conversational manner akin to the structure of the essay itself. To guide this conversation, we asked the scholars to answer the questions: “What was your first impression of the essay, and how has your own work been influenced, either directly or indirectly, by Dr Imanishi’s work?” and “In what way has Dr Imanishi’s concept of Karuchua been encompassed by Western approaches?” What ensued now lies before you. We feel privileged to present to you the first English translation of the original Japanese essay by Kinji Imanishi that has already inspired so many scholars and nonscholars alike in their quest for understanding the nature of social life

Chimpanzees behave prosocially in a group-specific manner

Funding: EJCvL was funded by a Postdoctoral Fellowship awarded by the Research Foundation Flanders (FWO) and an ERC-Synergy Grant (no. 609819) awarded to JC.Chimpanzees act cooperatively in the wild, but whether they afford benefits to others, and whether their tendency to act prosocially varies across communities, is unclear. Here, we show that chimpanzees from neighboring communities provide valuable resources to group members at personal cost, and that the magnitude of their prosocial behavior is group specific. Provided with a resource-donation experiment allowing free (partner) choice, we observed an increase in prosocial acts across the study period in most of the chimpanzees. When group members could profit (test condition), chimpanzees provided resources more frequently and for longer durations than when their acts produced inaccessible resources (control condition). Strikingly, chimpanzees’ prosocial behavior was group specific, with more socially tolerant groups acting more prosocially. We conclude that chimpanzees may purposely behave prosocially toward group members, and that the notion of group-specific sociality in nonhuman animals should crucially inform discussions on the evolution of prosocial behavior.Publisher PDFPeer reviewe

Evolution of Humanity: English Translation of the Original Essay by Kinji Imanishi. Including Commentaries by Contemporary Scholars

In 1952, Kinji Imanishi wrote a thought-provoking essay on the nature of animal societies. In this essay, he applied the concept of human culture (which he referred to as Karuchua) to nonhuman animals by giving different taxa a voice in a fable-like conversation, thereby aptly transcending speciesism. While thoroughly inspiring for scholars who have mastered the Japanese language, the essay was only known to non-Japanese-speakers by its English abstract. Here, we unveil the rest of the essay for the English-speaking community. Furthermore, to contextualize the seminal text, we asked contemporary scholars working in the field of (animal) culture to comment on the essay in a conversational manner akin to the structure of the essay itself. To guide this conversation, we asked the scholars to answer the questions: “What was your first impression of the essay, and how has your own work been influenced, either directly or indirectly, by Dr Imanishi’s work?” and “In what way has Dr Imanishi’s concept of Karuchua been encompassed by Western approaches?” What ensued now lies before you. We feel privileged to present to you the first English translation of the original Japanese essay by Kinji Imanishi that has already inspired so many scholars and nonscholars alike in their quest for understanding the nature of social life

Spontaneous social tool use in chimpanzees (Pan troglodytes)

This research was supported by the European Research Council (Synergy Grant 609819 SOMICS to Josep Call). Manon K. Schweinfurth was supported by the Swiss National Science Foundation (Grant P2BEP3 175269).Although there is good evidence that social animals show elaborate cognitive skills to deal with others, there are few reports of animals physically using social agents and their respective responses as means to an end—social tool use. In this case study, we investigated spontaneous and repeated social tool use behavior in chimpanzees (Pan troglodytes). We presented a group of chimpanzees with an apparatus, in which pushing two buttons would release juice from a distantly located fountain. Consequently, any one individual could only either push the buttons or drink from the fountain but never push and drink simultaneously. In this scenario, an adult male attempted to retrieve three other individuals and push them toward the buttons that, if pressed, released juice from the fountain. With this strategy, the social tool user increased his juice intake 10-fold. Interestingly, the strategy was stable over time, which was possibly enabled by playing with the social tools. With over 100 instances, we provide the biggest data set on social tool use recorded among nonhuman animals so far. The repeated use of other individuals as social tools may represent a complex social skill linked to Machiavellian intelligence.PostprintPeer reviewe

What isn't social tolerance? The past, present, and possible future of an overused term in the field of primatology

In the past four decades, the term social tolerance has been utilized to describe, explain, and predict many different aspects of primates' sociality and has been measured with a large range of traits and behaviors. To date, however, there has been little discussion on whether these different phenomena all reflect one and the same construct. This paper opens the discussion by presenting the historical development of the term social tolerance and a structured overview of its current, overextended use. We argue that social tolerance has developed to describe two distinct concepts: social tolerance as the social structure of a group and social tolerance as the dyadic or group-level manifestation of tolerant behaviors. We highlight how these two concepts are based on conflicting theoretical understandings and practical assessments. In conclusion, we present suggestions for future research on primate social tolerance, which will allow for a more systematic and comparable investigation of primate sociality.<br