According to a report in New Scientist, the tool-making behavior of New Caledonian crows may be simply part of their natural repertoire. If this finding turns out to be true, it would cast doubt on claims that the birds are intelligent.
A crow that astonished the world by bending a straight piece of wire was simply acting out behaviour in her species’ natural repertoire.
Betty bent a straight piece of garden wire into a neat hook to lift a food-baited bucket from a vertical tube in a laboratory at the University of Oxford in 2002.
At the time, it was known that New Caledonian crows manufacture tools from twigs in the wild, but it seemed highly unlikely that this involved bending.
The resulting paper from the experiment suggested that Betty had spontaneously come up with a clever solution after understanding the experimental task.
This shook the field of comparative cognition and was regarded as one of the most compelling demonstrations of intelligence in a non-human animal.
But recent field experiments by biologists at the University of St Andrews have found that tool bending is part of New Caledonian crows’ natural behaviour.
Researchers were astonished:
“We couldn’t believe our eyes,” said Christian Rutz leader of the project. “Most birds trapped sticks underfoot before bending the tool shaft by bill, but one also pushed tools against the logs to flex them, and another wedged them upright into holes before pulling the shaft sideways, just as Betty had done.”
One researcher put forward an explanation of the birds’ behaviour:
“Our observations raise the question of why wild crows would bend their stick tools as a matter of course,” said James St Clair, co-author of the study. “We believe a curved tool is advantageous, because the bird can position it in its bill so that the tool-tip is bang in the middle of the field of binocular vision.”
And the upshot?
“New Caledonian crows are gifted tool users,” St Clair said.
“The highly dexterous behaviour we observe in adult birds is the outcome of complex interactions between genetic predispositions and lifelong individual and social learning – a process that we don’t yet fully understand.
“In light of our new results, more experiments are needed to figure out what exactly these birds are capable of.”
Looks like proponents of animal rationality are back at square one, now that their star case has been called into question.
What do readers think?