Experiments on monkeys suggest that the animals can recognise and react to their own image in a mirror. They altered their posture to look at their own genitals and other body parts they couldn't see directly.
The rhesus macaques studied in the experiments may be telling us that the current "gold standard" test for self-awareness is not sensitive enough to identify all animals that are self-aware – although the method is steeped in controversy.
Evidence for self-awareness has so far been restricted to an elite including humans, chimpanzees, orang-utans, bonobos, gorillas, elephantsMovie Camera, dolphins and, possibly, magpiesMovie Camera.
All these animals pass the so-called "mark test", in which they are put to sleep, daubed with a spot of dye on the face to alter their appearance, then woken to see if they notice and react to the mark when they see it in a mirror.
Macaques have previously failed the mark test, and the animals tested in the current study were no exception. But they revealed by accident that they do indeed recognise themselves in mirrors. ...
via Monkeys bid to join elite self-awareness club - life - 29 September 2010 - New Scientist.