London, April 21 (ANI): Kiwi scientists have found that crows may be more innovative than was previously thought.
In the study, researchers from New Zealand's University of Auckland found that the birds were able to use three tools in succession to reach some food.
For their study, the researchers headed to the South Pacific island of New Caledonia, the home of Corvus moneduloides. They are the only birds known to craft and use tools in the wild.
The finding that they whittle branches into hooks and tear leaves into barbed probes to extract food from hard-to-reach nooks amazed scientists, who had previously thought that ability to fashion tools was unique to primates.
And further research revealed that New Caledonian crows are also innovative problem solvers, often rivalling primates.
Experiments have shown that the birds can craft new tools out of unfamiliar materials, as well as use a number of tools in succession.
To further understand how the birds perform these tasks, the research team set seven wild crows, which had temporarily been captured and placed in an aviary, a complicated problem.
The birds were presented with some out-of reach food; a long tool, which could be used to extract the food, but which was also out of reach, tucked behind the bars of a box; and a short tool, which could be used to extract the long tool, but which was attached to the end of a dangling piece of string tied to the crow's perch.
"The crows needed to understand they needed the short tool on the piece of string to get the long tool, and then use the long tool to get the food," the BBC quoted Professor Russell Gray, from the University of Auckland, as saying.
The seven birds were split into two groups. The first group of birds were given the chance to try out every individual step in the set-up, before they were presented with the complete multi-stage task.
"All these birds had to do was to put together things they could already do in the right sequence," Gray said.
Each of the three birds managed to solve the three-stage problem on their first attempt. A second group of birds was presented with a less familiar situation.
While they had previously been shown tasks where food was directly attached to string, and sticks could be used to grab out of reach food, they had never been given a situation where a tool was linked to the string or where one tool was needed to collect a second tool.
However, when presented with the multi-stage task, these birds also managed to reach their treat.ne bird, spent 110 seconds inspecting the apparatus before completing each of the steps without any mistakes. Another bird also completed on his first try, although he was initially puzzled by the string.
The other two birds solved the problem on their third and fourth attempts.
Study's lead author Alex Taylor said: "Finding that the crows could solve the problem even when they had to innovate two behaviours was incredibly surprising."
The research has been published in the Proceedings of the Royal Society B. (ANI)