A new study published this week in Science challenges the idea that only humans are capable of forming cooperative relationships and sharing resources between groups outside the family.
Many animals cooperate, such as wolf packs or pods of dolphins, but until now scientists believed that only humans were able to cooperate and share resources with groups with which they had no family relationship.
Researchers from Harvard University and the German Primate Center examined the prosocial behavior of bonobos (Paniscus bread), one of humanity’s closest living relatives, and discovered that their cooperation extends beyond their own group and cooperates socially with different groups.
Studying humans’ two closest living relatives, chimpanzees and bonobos, can help reconstruct ancient human traits such as cooperation and conflict. Although the two species live in similar social groups consisting of multiple adult members of both sexes, they differ fundamentally in the way they interact between social groups. Among chimpanzees, our most studied relatives, intergroup relations are predominantly hostile and lethal aggression is not uncommon. Therefore, models of human evolution often assume that group hostility and violence are inherent in human nature.
Our most sociable relatives
Studying bonobos reveals a different story. Endangered bonobos are notoriously difficult to study in the wild because they only live in remote and largely inaccessible areas of the Democratic Republic of Congo. Harvard Professor Martin Surbeck and lead author of the study, who established and leads the research at the Kokolopori Bonobos Reserve, notes: “Thanks to the close collaboration and support of the local Mongandu people of Kokolopori, in whose ancestral forest they roam the bonobos , It is possible to study this fascinating species.
Surbeck continued, “Research sites like Kokolopori not only contribute significantly to our understanding of the biology and evolutionary history of the species, but also play a critical role in the conservation of this endangered species.”
When different groups of bonobos come together, they often travel, rest, and eat together. Unlike chimpanzees, researchers have not observed fights between bonobos that resulted in fatal aggression. “While tracking and observing several groups of bonobos in Kokolopori, we are impressed by the remarkable tolerance between members of different groups. “This tolerance paves the way for prosocial cooperative behavior, such as forming alliances and sharing food between groups, a stark contrast to what we see in chimpanzees,” says Dr. Liran Samuni, group leader with Emmy Noether at the German Primate Center Göttingen and lead author of this study.
The study confirms that bonobos do not interact randomly between groups. Instead, collaboration takes place between a select few. “They prefer to interact with certain members of other groups who are more likely to return the favor, which leads to strong bonds between prosocial individuals,” says Surbeck. “Such connections are also central aspects of cooperation in human societies.”
“Bonobos show us that the ability to maintain peaceful relationships between groups while extending prosocial and cooperative actions to members of out-groups is not just human,” says Surbeck.
Samuni adds, “The opportunity to study how cooperation emerges in a species so closely related to humans challenges existing theories or at least provides ideas about the conditions that promote cooperation between groups in the face of conflict.”
Human cultures, traditions and social norms enable cooperation between our societies. The importance of this collaboration between different human groups is undeniable. It leads to the exchange of ideas, the spread of innovations and the accumulation of knowledge in space and time. Human networks promote the exchange of resources, which creates trade in materials and goods that can make up for deficits. Bonobos also share resources between groups and do so without strong cultural influence.
The study authors highlight the similarities between the social cooperation of bonobos and that of humans.
According to the authors, the bonobos’ findings should challenge the idea that culture and social norms are necessary components for the emergence of intergroup cooperation. Bonobos show that constant war between neighboring groups is not necessarily a human legacy and does not seem evolutionarily inevitable, the authors say.
Collaboration across social boundaries in bonobos