From PhysOrg:
Chimpanzees are self-aware and can anticipate the impact of their actions on the environment around them, an ability once thought to be uniquely human, according to a study released Wednesday. The findings, reported in the Proceedings of the Royal Society B, challenge assumptions about the boundary between human and non-human, and shed light on the evolutionary origins of consciousness, the researchers said. Earlier research had demonstrated the capacity of several species of primates, as well as dolphins, to recognize themselves in a mirror, suggesting a fairly sophisticated sense of self.
The most common experiment consisted of marking an animal with paint in a place — such as the face — that it could only perceive while looking at its reflection. If the ape sought to touch or wipe off the mark while facing a mirror, it showed that the animal recognised itself. But even if this test revealed a certain degree self-awareness, many questions remained as to how animals were taking in the information. What, in other words, was the underlying cognitive process?
More here.