'Hostilities began in an extremely violent way': How chimp wars taught us murder and cruelty aren't just human traits

War and violence can often seem like uniquely human acts that have been present for most of our recent History. But do other Animals wage "war"? In this excerpt from "The Beast Within: Human as Animals" (2024, Johns Hopkins University Press), scientific researcher Jessica Serra looks at the dark side of chimpanzees' (Pan troglodytes) behavior to show that our closest living relatives also have a taste for warfare.

Among nonhuman mammals, hostility between rival groups is quite widespread, but it rarely leads to death. The frequent fighting between males is most often ­limited to intimidation be­hav­ior. While certainly frightful, it is rarely fatal. ­There is one exception, however: our closest cousins, the chimpanzees! Ethological studies have shown animals to be capable of forming complex ­political alliances. ­English primatologist Jane Goodall made a major discovery on this subject when she revealed an unsuspected dark side in chimpanzees.

In 1974, when Goodall was studying the be­hav­ior of chimpanzee colonies in Gombe, Tanzania, she observed a social divide between two groups in one of the communities. The first group, called the Kasakela community ­because they occupied the north part of the park bearing this name, was composed of eight adult males and twelve adult females, as well as their young. The second group, called the Kahama community, consisted of six adult males, an adolescent male and three adult females.

The hostilities began in an extremely violent way when a male from the Kasakela group killed Godi, a male from the Kahama group. The rage of the Kasakelas continued to plague the Kahamas for the next four years, during which time six more males ­were killed. As for the Kahama females, two dis­appeared and three ­were beaten by a gang of violent males.

The end of this "four-­year war" resulted in the Kasakela community taking over the Kahama's territory. It was a short-­lived victory, however, since another community of chimpanzees living nearby managed to scare the Kasakelas away. 

Goodall recounted her poignant memories of this war in her memoir "Through a Win­dow: My Thirty Years with the Chimpanzees of Gombe." She recalls, "For several years I strug­gled to come to terms with this new knowledge. Often when I woke in the night, horrific pictures sprang unbidden to my mind — ­Satan [one of the apes], cupping his hand below Sniff's chin to drink the blood that welled from a great wound on his face; old Rodolf, usually so benign, standing upright to hurl a four-­pound [1.8 kilograms] rock at Godi's prostrate body; Jomeo tearing a strip of skin from Dé's thigh; Figan, charging and hitting, again and again, the stricken, quivering body of Goliath, one of his childhood heroes." 

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