Bearded Capuchin monkeys from Brazil show human-like skills according to a new study that finds similar strategical use of tools of humans. They were witnessed to use rocks to smash nuts open for snacks. Humans and the monkeys when given the task of smashing nuts take time placing the nuts in their most stable position on a stone “anvil” which keeps the tasty part of the nuts from getting away.
These monkeys showed the researchers that not only are they capable of using tools but also use them with which finesse as of humans. “Any individual can accommodate stones of different sizes, anvils of different angles and material and nuts of different shapes and sizes. In fact, some of these nuts people can’t crack.” said study leader Dorothy Fragaszy, a primate researcher at the University of Georgia. This ability may precede from human beings’ ability to make use of different tools for different situations and to use them with thought and precision under different conditions. “They were slamming the rock on that nut. It’s very impressive when you see it,” Dorothy Fragaszy said.
Bearded Capuchin monkeys crack hard nuts by putting them on pitted stone anvils and then hitting them hard with other large rocks. They were the first non-ape primates to be seen making use of tools in their habitats in the wild. Fragaszy and her colleagues saw how the monkeys have a rare habit of tapping the nuts many times against the stone pits before laying them down on it. To Fragaszy, the tapping may perhaps be a way to tell how hard the nut might be. The researchers brought palm nuts to bearded Capuchin monkeys habituating in Fazenda Boa Vista, Brazil. Ten of the monkeys gathered the nuts from the scientists. The scientists rolled the nuts on the ground to find their flat sides and marked a line and marked the other axis of the nut so they can identify how the Capuchin monkeys place the nuts in the video.
The video revealed that the bearded Capuchin monkeys were consistent in placing the nuts in the most stable position. 253 out of 302 attempts started with the line marking in the palm nuts stable axis facing up. The researchers also did a similar test with humans. Seven males and seven females volunteered and where given nuts to crack with stones like how capuchin monkeys did. The fourteen volunteers of men and women were blindfolded so to see if humans would and could place the nuts by feel just as how the Capuchin monkeys did.
71 percent of tries by the humans also placed the nuts in the most stable positioning. But unlike the monkeys, they did not knock the nuts on the stone as much as the monkeys. They instead rolled the nuts around their hands to feel the shape. The researchers wrote in the PLOS ONE journal that humans have much bigger hands than the bearded Capuchin that explained the difference in strategies.
“It’s skill in the way that we use that word to talk about human skills,” Fragaszy said. “It’s a goal-directed activity. It’s done fluidly. It’s done flexibly.” The results show that humans and monkeys share the ability to use tools skillfully, with minimal effort for maximum effect.