Add them to the growing list of animals that can recognize themselves when they look in a mirror: magpies. If you don't live in the West, you probably aren't familiar with them, but they are really neat birds that I happen to be rather fond of. They are showy, the West's version of a tropical-looking bird. I know some people don't like them because they're scavangers, but whatever. I think they're cool and they just got a whole lot more cool!
According to research published in the Public Library of Science - Biology, magpies passed the famous mirror test that psychologists have been using since the 1950s to determine when babies (and animals like apes, monkeys, dolphins and elephants) have a self-concept. Presumably, if they show evidence they know the image in the mirror isn't somebody else and show signs they recognize themselves in the mirror, then they have a sense of self.
The mirror test involves placing a mark on the individual while they are unconscious. Controls get touched, but no mark is left. When they wake up in front of a mirror if the marked ones touch the mark after looking in the mirror, they 'pass' the test. They also have to not touch the mark if they're not in front of the mirror.
Self-recognition is linked to highly developed understanding of social relationships, empathy and perspective taking.
According to the researchers, magpies were chosen because they compete with conspecifics for food that they hide and have a memory for where food is hoarded, making them good candidates for complex social understanding. They were also chosen because they're smarter than monkeys, i.e., magpies achieve the highest level of Piagetian object permanence (ability to recognize an object still exists even when it is out of sight, i.e. why peek-a-boo is so amusing with babies) whereas monkeys don't. Magpies are curious and "prone to approach new situations, making them ideally suited for an experiment that requires spontaneous interaction with a new and puzzling context," the researchers said.