Mysterious chimpanzee behaviour may reveal a form of spirituality

Researchers have documented chimpanzees accumulating rocks inside hollow tree trunks. The study’s author suggests such behaviour could be a sort of ancestral ritual.

Chimpanzees are the closest species to humans, for better or for worse. These primates, with whom we share 98.5 per cent of DNA, are able to use utensils (they use twigs to catch ants from anthills or rocks to crack open fruit), but they could be aggressive and brute, just as we do.


Scimpanzé alle prese con un formicaio
Chimpanzee uses a twig to catch ants


A video recorded by a group of researchers of the Humboldt University of Berlin led by Laura Kehoe shows an uncommon behaviour that could reveal another overlap between Homo sapiens e Pan Troglodytes: a sense of the sacred. The aim of the mission was observing an unstudied group of chimpanzees in the wild.


The images, obtained thanks to photo traps installed in the forest of Republic of Guinea, Western Africa, show a male individual getting close to a hollow tree trunk, grabbing a rock and throwing it against the tree. A second video shows a primate accumulating rocks inside a hollow tree trunk.

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According to the study, published in the Scientific Reports journal, such behaviour may have multiple interpretations. Some researchers suggest it could represent force competitions aimed to define hierarchies among the group’s males, while others think it is a form of communications aimed at reaffirm animals’ supremacy. However, according to Laura Kehoe, there’s an alternative explanation: it could be an ancestral ritual aimed to ingratiate divinities.


The accumulation of rocks made by chimpanzees inside hollow tree trunks could represent the construction of a rudimental sacred place. “What we have found might be more symbolic than a male display, and perhaps more reminiscent of our own past,” said Kehoe. “Even more intriguingly, we may have uncovered evidence of chimps creating a kind of symbolic ritual. Man-made stone collections are commonly observed across the world, including indigenous West African people who have been found to have stone collections at “sacred” trees that look eerily similar to what we have discovered here”.


Lo strano comportamento degli scimpanzé
Frames from the video grabbed in the Republic of Guinea thanks to photo traps show the mysterious behaviour of chimpanzees


Such discovery, though, doesn’t provide any answer, but raises fascinating unasked questions: “Are we the only species with spirituality?” To cast light on this mystery as well as on our origins, we must – first of all – protect these animals and their habitats: in the Ivory Coast alone, chimpanzee populations decreased by 90 per cent over the last 17 years.

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