Biologists at the University of Tübingen, Germany, have found that orangutans living in zoos can use tools to crack nuts without learning the skill. The authors of the work note that this is one of the few primate species with this ability.
The animal world continues to amaze scientists. What else can primates do?
As part of the study, scientists planted nuts and hammers in their enclosures at the Leipzig Zoo in Germany, four orangutans. They also gave similar items to eight orangutans at the Zurich Zoo. Of the 12 animals observed, four (one in Leipzig and three in Zurich) used wooden hammers to spontaneously crack nuts, despite having no prior experience.
“Orangutans can develop these complex behaviors solely through experience and learning,” said study lead author Eliza Bandini.
Interestingly, one orangutan tried to use an “anvil” (root of a tree or stone) as a hammer, but because it was attached to the ground, he quickly switched to a wooden hammer to crack the nuts. Three more orangutans decided to chop the nuts with their hands or teeth.
The study authors note that until now, wild orangutans have not been seen cracking nuts with tools. Only a few species of mammals in the wild are known to do this, including chimpanzees. Some scientists thought this behavior required learning ability, but new research shows that it doesn't.