Impartial Third-Party Interventions in Captive Chimpanzees: A Reflection of Community Concern

Abstract

Because conflicts among social group members are inevitable, their management is crucial for group stability. The rarest and most interesting form of conflict management is policing, i.e., impartial interventions by bystanders, which is of considerable interest due to its potentially moral nature. Here, we provide descriptive and quantitative data on policing in captive chimpanzees. First, we report on a high rate of policing in one captive group characterized by recently introduced females and a rank reversal between two males. We explored the influence of various factors on the occurrence of policing. The results show that only the alpha and beta males acted as arbitrators using manifold tactics to control conflicts, and that their interventions strongly depended on conflict complexity. Secondly, we compared the policing patterns in three other captive chimpanzee groups. We found that although rare, policing was more prevalent at times of increased social instability, both high-ranking males and females performed policing, and conflicts of all sex-dyad combinations were policed. These results suggest that the primary function of policing is to increase group stability. It may thus reflect prosocial behaviour based upon “community concern.” However, policing remains a rare behaviour and more data are needed to test the generality of this hypothesis.

Third-party punishment increases cooperation in children through (misaligned) expectations and conditional cooperation

“…[To date, it is unclear whether humans execute costly punishment (i) because they view defection as a violation of a broadly recognized group norm or (ii) because of a personal aversion to defection.] Whereas some research (32) suggests the existence of third-party punishment among nonhuman primates in the form of third-party policing (which refers to impartial interventions to control conflicts between conspecifics), others argue that impartial interventions in conflict situations are unlikely to qualify as third-party punishment, but rather are motivated by selfishness that yield cooperation only as a by-product (33). Thus, the deliberate punishment of defectors by third parties is a likely candidate to explain high cooperation rates in humans.…”

No third-party punishment in chimpanzees

“…Prototypically, human third-party punishment involves responses by an unaffected individual to violations of social norms, such as socially agreed upon rules for cooperation (13). Processes resembling third-party punishment have been described in other animals (17)(18)(19)(20)(21)(22), including in nonhuman primates, namely, chimpanzees (Pan troglodytes) (23,24) and pigtailed macaques (Macaca nemestrina) in which powerful individuals successfully intervene in fights (25) and whose absence results in increased conflicts among the remaining group members (26). However, the removal of a dominant is likely to create a power vacuum, which results in increased conflict as the other animals jockey for status, and any cooperativeness caused by the dominant's presence might arise as a byproduct.…”

Evolutionary Origins of Morality: Insights From Non-human Primates

“…However, exceptions exist, which eventually even include infanticide (Townsend et al, 2007). Naturalistic observations show that bystanders who observe harmful behaviors often show strong reactions (Goodall, 1971;de Waal, 1991), such as waa barks (protest vocalizations: Clay et al, 2016), and even direct interventions in the form of policing (Rudolf von Rohr et al, 2012). Harmful behaviors toward infants elicit particularly strong reactions (Goodall, 1977;Townsend et al, 2007), such as interventions and defense of the mother-infant pair by multiple group members, sometimes culminating in highly dramatic situations.…”