Humans aren’t the only species who can make good friends with their neighbors, reveals new research.
Scientists found that bonobo monkeys can form “strong and strategic” cooperative relationships and share resources with non-family groups.
The research team, from Harvard University and the German Primate Centre, examined the behavior of the endangered primates, who are one of man’s closest living relatives, deep in the Congolese jungle.
The findings, published in the journal Science, showed that bonobos’ cooperation extended beyond their own immediate group.
The researchers were struck by the “remarkable levels of tolerance” between members of different groups of bonobos, compared to between chimpanzee groups.
They said studying humans’ two closest living relatives, chimps and bonobos, can help reconstruct ancestral human traits, such as cooperation and conflict.
But, despite living in similar social groups composed of multiple adult members of both sexes, the two species are “fundamentally different” in how they interact across social groups.
Relationships between different groups of chimps are predominantly hostile, and lethal aggression is not uncommon.
As a result, models of human evolution often assume that group hostility and violence are innate to human nature.
But studying the bonobos unearthed a different story.
The endangered primates are notoriously difficult to study in their natural habitat, as they only live in remote, largely inaccessible areas of the Democratic Republic of the Congo.
Study senior author Harvard Professor Martin Surbeck established and directs research at the Kokolopori Bonobo Reserve.
He said: “It is through strong collaborations with and the support of the local Mongandu population in Kokolopori, in whose ancestral forest the bonobos roam, that studies of this fascinating species become possible.
“Research sites like Kokolopori substantially contribute not only to our understanding of the species’ biology and our evolutionary history but also play a vital role in the conservation of this endangered species.”
He explained that when different groups of bonobos meet, they often travel, rest, and feed together.
Unlike among chimps, researchers have not observed bonobo disputes that lead to lethal aggression.
Study lead author Dr Liran Samuni, of the German Primate Centre in Göttingen, said: “Tracking and observing multiple groups of bonobos in Kokolopori, we’re struck by the remarkable levels of tolerance between members of different groups.
“This tolerance paves the way for pro-social cooperative behaviors such as forming alliances and sharing food across groups, a stark contrast to what we see in chimpanzees.”
The study showed that the bonobos do not interact randomly between groups. Instead, cooperation happens between a select few.
Surbeck said: “They preferentially interact with specific members of other groups who are more likely to return the favor, resulting in strong ties between pro-social individuals.
“Such connections are also key aspects of the cooperation seen in human societies.
“Bonobos show us that the ability to maintain peaceful between-group relationships while extending acts of pro-sociality and cooperation to out-group members is not uniquely human.”
Dr. Samuni added: “The ability to study how cooperation emerges in a species so closely related to humans challenges existing theory, or at least provides insights into the conditions that promote between-group cooperation over conflict.”
The research team emphasized the similarities between bonobo social cooperation and that of humans.
They said insights from bonobos should challenge the idea that culture and social norms are necessary components for cooperation between groups to emerge.
Dr. Samuni said the bonobos show that constant warfare between neighboring groups is not necessarily a human legacy and does not seem evolutionarily inevitable.
Produced in association with SWNS Talker