There is robust evidence to suggest that unlike great apes, monkeys never arrive at the realization that the source of their reflection in a mirror is their own body. This failure to achieve self-recognition may be due to a lack of a sufficiently integrated concept of self in monkeys. The failure of monkeys to show self-recognition is a persistent finding in spite of many experimental manipulations aimed at enhancing their understanding of reflections. There is no obvious relationship between self-recognition ability and the capacity for tool-use; great apes and capuchin monkeys are both competent tool-users but only the former show self-recognition. Recently, evidence has been accumulating for a great ape - monkey divide in another fundamental sociocognitive ability, namely visual perspective-taking. Perspective-taking may be intimately related to self-recognition.

Key words: self-recognition, perspective-taking, tool-use, monkeys, apes