Beran, Smith, and Perdue (2013) found that chimpanzees showed metacognitive monitoring in the information-seeking task. In their studies, three language-trained chimpanzees were asked to use the keyboard to name the food item in order to get the food. The food in the container was either visible to them or they had to move toward the container to see its contents. Studies shown that chimpanzees were more often to check what was in the container first if the food in the container was hidden. But when the food was visible to them, the chimpanzees were more likely to directly approach the keyboard and reported the identity of the food without looking again in the container. Their results suggested that chimpanzees know what they have seen and show effective information-seeking behavior when information is incomplete.