This article focuses on mirror self-recognition, the ability to recognize one's own image in a mirror. It presents the result of the first experiment on mirror self-recognition which showed that chimpanzees are able to learn that the chimps they see in the mirror are not other chimps, but themselves, as evidenced by self-directed behaviour. It reviews evidence for neural network for self-recognition and self-other differentiation and cites evidence that frontal cortex and cortical midline structures are implicated in self-recognition tasks. It (...) also suggests that the mirror self-recognition ability correlates to large brain size relative to the animal's body size. (shrink)