When chimpanzees were first seen using tools in Liberia in 1951, little was known about great ape behavior in the wild. The sighting was published as a short note by Harry Beatty in the Journal of Mammalogy (recounted by primatologist Frans de Waal in The Ape and the Sushi Master).
After spotting a shell mound, Beatty saw a chimp “come ambling round a bend bearing an armful of dried palm nuts,?sit down beside a rock, select a nut, place it on a flat rock surface, and pound it with another rock to extract the meat. Thirty years passed before primatologists would describe the same behavior in chimps in Guinea. By then it was clear that nonhuman primates used objects for many tasks, from intimidating rivals and predators to taking leaf sponge baths and processing food. Still, the notion that tool use was not the sole province of human intelligence was difficult for some to accept.
Though chimps, bonobos, orangutans, and gorillas all use tools in captivity, often imitating behaviors of their keepers, tool use had not been observed for gorillas in the wild. (Chimps famously use sticks to fish for termites and rocks to crack nuts in the wild; orangutans use sticks to extract seeds from the spiny, sharp husk of Neesia fruits in the wild, and bonobos use various tools, including moss as sponges and leafy twigs to swat away bees.) That no one has ever observed wild gorillas using tools—despite decades of intensive study—prompted scientists to speculate that gorillas lost the skill because they didn't need it. The largest of the great apes, gorillas can gnash nuts between their teeth and simply smash termite mounds to release their denizens.
But now, as part of an ongoing study of western gorillas in Nouabalé-Ndoki National Park in the Republic of Congo, Thom
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Source:PLoS Biology