Deadly attacks by coalitions of chimpanzees on gorillas in the wild have been observed for the first time.
Chimpanzees and gorillas are typically relaxed around each other in Gabon’s Loango National Park – but recently violent encounters have been documented, according to a study published in the journal Nature.
Researchers at the University of Osnabruck and the Max Planck Institute for Evolutionary Anthropology in Leipzig are unsure whether the attack is the result of competition for food or for other reasons, and continue to investigate.
The researchers’ work examines the behavior of around 45 chimpanzees in the park, including group composition, social relationships, interactions with neighboring groups, hunting behavior, tool use and communication skills. interest anthropologists.
“Interactions between chimpanzees and gorillas have so far been considered relatively relaxed,” Professor Simone Pika told Osnabruck.
“We have regularly observed the two species interacting peacefully in the trees foraging for food. Our colleagues in Congo have even witnessed playful interactions between the two species of great ape.”
So what exactly happened here? As the study’s first author, Lara Southern, recalls, the first attack took place in 2019: “At first, we only noticed chimpanzee calls and thought we were observing a typical encounter between individuals from neighboring chimpanzee communities.
“But then we heard chest pounding, a characteristic manifestation of gorillas, and we realized that the chimpanzees had encountered a group of five gorillas.”
In the first of two encounters, which lasted 52 and 79 minutes, the group of 27 chimpanzees formed a coalition to attack a group of five gorillas.
In the second encounter, also involving some 27 chimpanzees, the coalition attacked a group of seven gorillas.
“The first event occurred after a land patrol in which the males made a deep foray into nearby chimpanzee territory. The second event occurred at the start of a suspected land patrol,” said the ‘study.
“The first encounter resulted in the death of an infant gorilla and three injured chimpanzees; the second resulted in the death of an infant gorilla. consumed by an adult female chimpanzee “, according to the study.
He noted: “The main aggressors in both events were adult male chimpanzees. “
The inter-species violence may have been caused by hunting and competition for food, the researchers say.
“It could be that the sharing of food resources by chimpanzees, gorillas and forest elephants in Loango National Park could lead to increased competition and sometimes even deadly interactions between the two great ape species,” said Dr Tobias Deschner.
“We are only at the beginning of understanding the effects of competition on the interactions between the two great ape species in Loango,” added Professor Pika.
“Our study shows that there is still a lot to explore and discover about our closest living relatives, and that Loango National Park with its unique mosaic habitat is a unique place to do so.”