'X' marks the spot, putting elephants among the elite
US scientists made the discovery after standing three female elephants in front of an 8ft tall mirror.
Eventually one elephant, named Happy, began using her trunk to repeatedly touch an 'X' painted on her forehead
The mark could only be seen in the mirror and Happy ignored another invisible mark on her head proving she was not reacting to smell and touch.
Only highly intelligent animals with strong social networks are capable of mirror self-recognition.
Previously among non-human animals the trait has only been shown to exist in great apes and bottlenose dolphins.
Study leader Joshua Plotnik, of Emory University, Georgia, said: "The social complexity of the elephant, its well-known altruistic behaviour and, of course, its huge brain, made the elephant a logical candidate species for testing in front of a mirror."
Less than half of chimpanzees tested the same way pass.