Magpies can recognise themselves in a mirror, scientists have found - the first time self-recognition has been observed in a non-mammal.

Until relatively recently, humans were thought to be uniquely self-aware.

Dr Helmut Prior, from the Goethe University in Frankfurt, and his colleagues carried out a series of tests on five hand-reared birds.

"The findings do, however, show that magpies respond in the mirror and mark test in a manner so far only clearly found in apes, and, at least suggestively, in dolphins and elephants.

"This is a remarkable capability that is at least a pre-requisite of self-recognition and might play a role in perspective taking."