19 August 2008

Nature: Magpies Recognize Themselves in Mirror

From New Scientist: "Self-recognition, once thought to be an ability enjoyed only by select primates, has now been demonstrated in a bird.

"The finding has raised questions about part of the brain called the neocortex, something the self-aware magpie does not even possess.

"In humans, the ability to recognise oneself in a mirror develops around the age of 18 months and coincides with the first signs of social behaviour.

"So-called 'mirror mark tests,' where a mark is placed on the animal in such a way that it can only be observed when it looks at its reflection, have been used to sort the self-aware beasts from the rest.

"Of hundreds tested, in addition to humans, only four apes, bottlenose dolphins and Asian elephants have passed muster.

"Helmut Prior at Goethe University in Frankfurt and his colleagues applied a red, yellow or black spot to a place on the necks of five magpies.

"The stickers could only be seen using a mirror. Then he gave the birds mirrors.Catch a glimpseThe feel of the mark on their necks did not seem to alarm them.

"But when the birds with coloured neck spots caught a glimpse of themselves, they scratched at their necks - a clear indication that they recognised the image in the mirror as their own.

"Those who received a black sticker, invisible against the black neck feathers, did not react.

"Self-recognition was thought to reside in the neocortex, but birds don't have one. Franz de Waal at Emory University in Atlanta points out that the magpie does nevertheless have a big brain. 'You need a large brain with a lot of connectivity,' he says. 'If it had been a sparrow, it would have been a problem.'

"The authors suggest that self-recognition in birds and mammals may be a case of convergent evolution, where similar evolutionary pressures result in similar behaviours or traits, although they arrive at them via different routes.

"De Waal agrees: 'Magpies are known for their ability to steal shiny objects and to hide away their loot. It's not too far-fetched that a master thief like a magpie has that perspective-taking ability,' he says, referring to the idea that the birds have a 'theory of mind.'"

But do they care what they look like in the morning?

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