Studies highlight intelligence of birds
Researchers from Austria and the United Kingdom have investigated the efficiency and flexibility of the New Zealand parrot Kea and the New Caledonian crow, what experts believe are members of the two most intelligent avian families on the planet. They reported their findings in two studies presented in the journals PLoS ONE and Biology Letters, shedding light on the birds' innovative abilities to accomplish certain goals but using diverse ways to do so. The research was funded in part by the SOMACCA ('The syntax of the mind: a comparative computational approach') project, led by Professor Tecumseh Fitch from the University of Vienna in Austria, which has clinched a European Research Council grant worth EUR 1.96 million under the EU's Seventh Framework Programme (FP7).
Parrots and Corvids (birds of the family that includes ravens, crows and magpies) never cease to amaze scientists when it comes to their intelligence, especially regarding their ability to solve technical problems. A case in point is the New Caledonian crow (Corvus monduloides) that makes and uses elongated objects like sticks as tools to look for grubs in tree bark and dead wood. The mountain parrot Kea (Nestor notabilis) also has a knack for using objects found in the wild to knock a food reward out of place.
The New Caledonian crow is black and around 40 centimetres (cm) long, and the Kea is olive green with red underwings and about 45 cm in body length. The Kea makes its home in the mountain region of the South Island of New Zealand.
Collaborating with colleagues from the University of Oxford in the United Kingdom, the University of Vienna researchers used a Multi Access Box (MAB) paradigm in a transparent Plexiglas cube to compare the cognitive mechanisms of six Kea and five New Caledonian crows. The team assessed how the birds would get their food reward, which was presented on a platform in the centre of the box.
Explaining the process, lead author of both papers Dr Alice Auersperg from the Department of Cognitive Biology at the University of Vienna says: 'The animals could choose between pulling a string which was tied around the reward, pulling a hook-shaped lever to open a window, inserting a marble (compact tool) into a curved ball-path leading towards the reward or inserting a rod-shaped stick-tool into an opening and manoeuvre it over a gap towards the food in order to push the reward off its platform.'
For his part, co-author Dr Gyula Gajdon, who is also from the University of Vienna, comments: ' The animals could choose which solution they wanted to employ first. Once they had established a solution and had used it a certain number of times we blocked the entrance, forcing them to switch to another. This way we could observe not only the differences in the order of solutions that the animals established but also how quickly they were able to switch.'
In terms of challenges, the Kea's biggest hurdle was to use a stick-like object as a tool. This bird is not a natural tool user in the wild. For the New Caledonian crow, the hardest challenge was to open a window by pulling a hook-shaped lever. This bird does not pull or tear objects.
The researchers say these latest findings will help strengthen our understanding of the evolution of intelligence.