**
In a groundbreaking study published in *Science*, researchers have documented an unprecedented instance of aggression among wild chimpanzees, suggesting that these primates can exhibit complex social behaviours reminiscent of human conflict. This remarkable observation took place in Uganda’s Kibale National Park, where a once-cohesive community of Ngogo chimpanzees has fractured into two rival factions, igniting what may be the first recorded case of civil unrest within a chimpanzee group.
A Telling Observation
The origins of this discord can be traced back to June 2015 when primatologist Aaron Sandel noticed unusual behaviour among the Ngogo chimps. As the wider group approached, the chimpanzees in his view exhibited signs of anxiety; they grimaced and sought comfort from one another, indicating an unsettling shift in their social dynamics. Sandel later reflected that this was an early indicator of a conflict that would escalate dramatically over the following years.
The study indicates that from 2015 onwards, the Ngogo chimpanzee community, previously known for their social cohesion, began to splinter. By 2018, the group had divided into the western and central factions, with the western chimps subsequently launching 24 coordinated attacks against their former companions, resulting in the deaths of at least seven adult males and 17 infants.
The Roots of Division
The researchers attribute this fracturing to a series of social upheavals, including the deaths of key elder members and a shift in leadership dynamics. Notably, on the day of Sandel’s observation, the alpha male had displayed submissive behaviour towards another chimp, signalling a potential shift in power that may have contributed to the group’s fragmentation.
The loss of influential individuals likely diminished the bonds that held the group together, making them susceptible to division. Furthermore, a disease outbreak in 2017 appears to have accelerated this process of polarisation, destabilising the already fragile social structure.
Implications for Conservation
The consequences of these findings are alarming for chimpanzee conservation efforts. The study highlights that incidents of in-group violence among chimpanzees are exceedingly rare, occurring approximately every 500 years. However, the researchers caution that human activities—such as deforestation, climate change, and disease—could exacerbate tensions within chimp communities, leading to more frequent occurrences of such conflicts.
Brian Wood, an evolutionary anthropologist from UCLA, emphasised the evolutionary advantage that the western group could gain from their aggressive actions. By undermining the central chimps, they not only increase their own chances of survival but also diminish their competitors’ reproductive success. The aftermath of these attacks has resulted in the lowest documented survivorship rates within a wild chimpanzee community, raising serious questions about the long-term impacts on their populations.
Sylvain Lemoine, a professor of biological anthropology at the University of Cambridge, described this phenomenon as the first thoroughly documented case of civil warfare among chimpanzees. He noted the significance of social ties and network connectivity in maintaining group cohesion, underscoring how fragile these connections can become when reliant on a limited number of key individuals.
Why it Matters
This study challenges our understanding of primate behaviour, revealing that even in species devoid of cultural markers, complex social dynamics can lead to intra-group violence. The implications extend beyond chimpanzees, prompting a re-evaluation of human societal structures. As we confront our own conflicts, the Ngogo chimpanzees serve as a poignant reminder of the delicate balance between cooperation and division, urging us to reflect on the underlying factors that can drive communities apart. Understanding these dynamics is crucial not only for primate conservation but also for fostering harmony within our own societies.