The world's largest known group of wild chimpanzees has split and been locked in a vicious 'civil war' for the last eight years, according to researchers. It is not clear exactly why the once close-knit community of Ngogo chimpanzees at Uganda's Kibale National Park are at loggerheads, but since 2018 the scientists have recorded 24 killings, including 17 infants.
These were chimps that would hold hands, lead author Aaron Sandel said. Now they're trying to kill each other.
The study, published in the journal Science, says the intensity and duration of the violence may inform how early human conflict developed. Sandel, an anthropologist from the University of Texas in the US, and co-director of the Ngogo Chimpanzee Project, says chimpanzees are 'very territorial' and have 'hostile interactions with those from other groups'.
[It's] like a fear of strangers, he told the Science podcast. But over several decades, he said the nearly 200 Ngogo chimpanzees had lived in harmony. They were divided into two sets - known to researchers as Western and Central - but had existed overall as a cohesive group.
Sandel first noticed them polarising in June 2015 when the Western chimpanzees ran away and were chased by the Central group. Chimpanzees are sort of melodramatic, he said, explaining that following arguments there would ordinarily be screaming and chasing and then later, they would groom and cooperate.
However, following the 2015 dispute, researchers observed a six-week avoidance period between the two sets, with interactions becoming more infrequent and aggressive. Following the emergence of the two distinct groups in 2018, members of the Western group began attacking the Central chimpanzees. In 24 targeted attacks since the split, at least seven adult males and 17 infants from the Central chimps have been killed, while researchers believe the actual number of deaths may be higher.
Factors like the group size and competition for resources, as well as 'male-male competition' for reproduction, have been highlighted as influential. However, three specific catalysts for the civil war have been identified:
1. The deaths of five adult males and one adult female in 2014 may have disrupted their social networks.
2. A change in the alpha male the following year coincided with the first signs of separation between the two groups.
3. The deaths of 25 chimpanzees, including four adult males and 10 adult females due to a respiratory epidemic in 2017 further exacerbated tensions, as one of the deceased was crucial for connecting both groups.
Sandel and his colleagues emphasized the importance of understanding these dynamics in relation to human conflict and warfare. They confronted the notion that underlying human conflicts are often tied to constructs like religion, ethnicity, and political beliefs, suggesting instead that relational dynamics can play a significant role.
James Brooks, a researcher at the German Primate Center, remarked on the importance of learning from such group-based behaviors of other species to better grasp the implications for human societies.
These were chimps that would hold hands, lead author Aaron Sandel said. Now they're trying to kill each other.
The study, published in the journal Science, says the intensity and duration of the violence may inform how early human conflict developed. Sandel, an anthropologist from the University of Texas in the US, and co-director of the Ngogo Chimpanzee Project, says chimpanzees are 'very territorial' and have 'hostile interactions with those from other groups'.
[It's] like a fear of strangers, he told the Science podcast. But over several decades, he said the nearly 200 Ngogo chimpanzees had lived in harmony. They were divided into two sets - known to researchers as Western and Central - but had existed overall as a cohesive group.
Sandel first noticed them polarising in June 2015 when the Western chimpanzees ran away and were chased by the Central group. Chimpanzees are sort of melodramatic, he said, explaining that following arguments there would ordinarily be screaming and chasing and then later, they would groom and cooperate.
However, following the 2015 dispute, researchers observed a six-week avoidance period between the two sets, with interactions becoming more infrequent and aggressive. Following the emergence of the two distinct groups in 2018, members of the Western group began attacking the Central chimpanzees. In 24 targeted attacks since the split, at least seven adult males and 17 infants from the Central chimps have been killed, while researchers believe the actual number of deaths may be higher.
Factors like the group size and competition for resources, as well as 'male-male competition' for reproduction, have been highlighted as influential. However, three specific catalysts for the civil war have been identified:
1. The deaths of five adult males and one adult female in 2014 may have disrupted their social networks.
2. A change in the alpha male the following year coincided with the first signs of separation between the two groups.
3. The deaths of 25 chimpanzees, including four adult males and 10 adult females due to a respiratory epidemic in 2017 further exacerbated tensions, as one of the deceased was crucial for connecting both groups.
Sandel and his colleagues emphasized the importance of understanding these dynamics in relation to human conflict and warfare. They confronted the notion that underlying human conflicts are often tied to constructs like religion, ethnicity, and political beliefs, suggesting instead that relational dynamics can play a significant role.
James Brooks, a researcher at the German Primate Center, remarked on the importance of learning from such group-based behaviors of other species to better grasp the implications for human societies.
