A population of white-faced capuchin monkeys in Panama has recently entered the Stone Age by using stone tools to break nuts and shellfish. This makes them the fourth type of primates, after humans, to exhibit this behavior. The monkeys inhabit Jicarón island, part of the Coiba National Park in Panama, with only the males in a specific region of the island using tools. Researchers were surprised by the localized nature of this behavior, which was first observed in 2004. The team believes that the innovation may have started with a particularly clever individual whose behavior was then copied by others. Further research and observations are needed to fully understand this phenomenon. These white-faced capuchins are only the second American species to enter the Stone Age, with another group of capuchins in South America also using stone tools for centuries. The other two primate species with this behavior are macaques in Thailand and chimpanzees in West Africa.
