. One of them could see the chimpanzee, while the other could not see it despite facing the chimpanzee; either because she had a bucket on her head or because she was wearing an eye mask (see picture). Povenelli and Eddie discovered that the chimpanzee did not show a preference for begging for food from those who could see it, which shows that the chimpanzees did not understand the connection between "seeing" and "knowing".