Wild chimpanzees in Guinea-Bissau have been observed performing a bizarre 'bowling' ritual, hurling rocks at trees in a behaviour that mimics cricket. Scientists reported the behaviour, known as accumulative stone throwing, at Boé National Park, where the animals were seen 'bowling' at a tree stump.
Ritual behaviour recorded on video
Video recordings show wild western chimpanzees, usually adult males, throwing rocks at specific trees and repeatedly returning to these trees to perform the behaviour. While throwing, the chimpanzees pant a loud, long-distance communicative signal.
The study found that they sometimes repeatedly hit their hands and feet on the tree in a behaviour called buttress drumming, acting as their own 'Barmy Army'.
Evolutionary insights
The author of the study wrote: "Given our evolutionary relatedness to chimpanzees, we hope accumulative stone throwing can help us understand the emergence of complex communication and stone tool use over the course of human evolution. Pant hooting and buttress drumming are both part of the male chimpanzee display, suggesting that accumulative stone throwing might represent a modification of this common behavior. It is likely a cultural behavior due to its limited distribution, and because the availability of rocks and trees does not guarantee the presence of an accumulative stone throwing site."
Previous primate-human similarities
This is not the first time apes have shown similarities to humans. Recent research indicated monkeys and apes are even more alike to humans than previously believed, with the creatures keeping other animals as companions. Scientists at the University of Oxford discovered that non-human primates frequently engaged with lizards, deer, birds, squirrels and even dogs in ways similar to how humans treat their pets, including playing with and grooming their animal companions.
The pairings were not restricted to one species, with 88 different primate species showing the inclination to care for and play with a vast range of animals. Cases included chimpanzees grooming red-tailed monkeys, playful macaques relishing the company of chickens, and capuchins nurturing an abandoned marmoset for several months.
