Brainy crow upsets pecking order

A crow may have fashioned her way into history by demonstrating an understanding of Archimedean physics. Betty the New Caledonian crow made a tool from a piece of garden wire and used it to hook a tasty morsel of meat out of a tube too deep for her beak.

The experiment once again raises questions about the uniqueness of human intelligence. The young bird - kept in the laboratory of an Oxford University behavioural ecology research group for the past two years - had never before seen garden wire.

And yet, Alexander Weir, Jackie Chappell and Alex Kacelnik report in Science today, when they supplied Betty with an appetising challenge and a 90mm length of pliant garden wire 0.8mm thick, she knew what to do. She first tried to see whether the straight wire would retrieve the meat.

When that did not work, she either wedged one end of the wire in sticky tape around the bottom of the tube, or she held it in her feet. She then pulled the other end with her beak and bent it at an angle. In nine out of 10 attempts she got the food within two minutes.

Chimpanzees in the wild use rudimentary tools - sticks to poke into termite nests - and show some understanding of numbers. But they are close relatives of humans. The experiments, say Professor Kacelnik and his colleagues, raise the possibility that New Caledonian crows "may rival non-human primates in tool-related cognitive capabilities". In other words, these birds are not bird-brained.

Eight years ago, a biologist watched the crows in their native forests in the south Pacific, making two distinct kinds of tool out of twigs and then using them to fish for larvae in inaccessible bits of wood. He compared their tool-making skills to early stone age humans.

The Oxford experiment was an deliberate attempt to address a puzzle. Would the crows recognise a potential tool in something they had never seen before?

"The question is: what kind of physics is it they understand? If you see a problem, pick up a straight wire and without instruction bend it into the right shape, and then extract the food, that means the animal is behaving as if it understands the required physical properties of an instrument," Prof Kacelnik said.

"It would be wrong to think there is only one kind of intelligence, and it has to be the one we happen to possess," Prof Kacelnik said. "Animals have the abilities they need for the circumstances in which they evolved, and we suspect that these animals are exceedingly clever - if you want to use the word - for the problems they normally face."