Ape Is First Known Wild Tool-using Gorilla
Photograph courtesy Breuer, Ndoundou-Hockemba, Fishlock et al, PLoS Biology
An adult female lowland gorilla in the Republic of the Congo's Nouabalé-Ndoki National Park uses a walking stick to gauge the water's depth in a file picture. The behavior, documented in a 2005 study in the journal PLoS Biology, was the first evidence that wild gorillas use tools.
Previously, chimpanzees, bonobos, and orangutans had all been observed using tools. But scientists had speculated that gorillas had lost such skills out of lack of necessity, according to the study. After all, gorillas, the largest of the great apes, can easily crush nuts with their teeth or smash termite mounds without needing tools.
(See pictures of Congo's lowland gorillas in National Geographic magazine.)
Overall, the walking-stick "observations suggest that the intelligence required for tool use evolved before the gorilla lineage split off from humans and the other great apes—providing further evidence that intelligence is not unique to humans," according to the synopsis of the study.
Indeed, "gorillas have tended to be considered the least smart of the great apes, so this is good, because it brings them into the fold," Russon said. Even so, "I don't think [gorillas using tools] is a major leap forward—they do it in zoos, and even monkeys use stick tools."
Updated August 9, 2011