Bonobos, chimpanzees and orangutans understand that others can be convinced of something that is not true

We all know that the way someone sees the world, and the way it really is, are not always the same. This ability to recognize that someone’s beliefs may differ from reality has long been seen as unique to humans. But new research on chimpanzees, bonobos and orangutans suggests our primate relatives may also be able to tell when something is just in your head. The study was led by researchers of Duke University, Kyoto University, the University of St. Andrews and the Max Planck Institute for Evolutionary Anthropology.