Mirror, mirror on the wall...

London: Magpies can recognise themselves in a mirror, highlighting the mental skills of some birds and confounding the notion that self-awareness is the exclusive preserve of humans and a few higher mammals.

It had been thought only chimpanzees, dolphins and elephants shared the human ability to recognise their own bodies in a mirror.

But German scientists reported that magpies - a species with a brain structure very different from mammals - could also identify themselves.

"It shows that the line leading to humans is not as special as many thought," lead researcher Helmut Prior of the Institute of Psychology at Goethe University in Frankfurt told Reuters. "After finding this kind of intelligence in apes, many people thought it had developed once in one evolutionary line with humans at the end. The bird studies show it has developed at least twice."

The discovery of self-awareness in magpies follows a 2002 study in which a crow stunned researchers with its tool-making skills, by twisting a wire into a hook to lift food from a tube.

The research was published in the Public Library of Science journal PLoS Biology and is available online.