Goffin's cockatoo, a native Indonesian parrot species, can solve a complex puzzle which involves unlocking a series of locks, reports a study from University of Oxford.
In the study, ten untrained Goffin's cockatoos were given a task of opening several locks one after the other to get a reward (a nut). There were five different locks that the birds were made to open consecutively. The birds had to remove a pin, a screw and a bolt, and then shift the lock 90 degrees to shift a latch.
A bird named Pipin solved the puzzle in about two hours. The other birds either took more time or completed the task after seeing other parrots perform.
Researchers said that the birds displayed a 'cognitive ratchet' process as once they opened a lock with great difficulty; they never forgot how to open it again. The birds also were persistent in their efforts, even though they were given the nut only after opening all five locks.
In the second part of the study, the birds were presented with another set of locks, resembling the first one. However, some locks were altered. This was done to know whether the birds had learnt to repeat the sequence or not.
"After they had solved the initial problem, we confronted six subjects with so-called 'transfer tasks' in which some locks were re-ordered, removed, or made non-functional. Statistical analysis showed that they reacted to the changes with immediate sensitivity to the novel situation," Dr Alice Auersperg, who led the study at the Goffin Laboratory at Vienna University.
"We cannot prove that the birds understand the physical structure of the problem as an adult human would, but we can infer from their behaviour that they are sensitive to how objects act on each other, and that they can learn to progress towards a distant goal without being rewarded step by step," said Professor Alex Kacelnik of Oxford University's Department of Zoology, a co-author of the study, according to a news release.
A related study had earlier shown that Goffin's cockatoos display self control, a trait that was considered to be uniquely human. Recently, BBC reported the story of cockatoo - named Figaro - that was seen using a stick as a tool to reach nuts outside its cage. These birds aren't known to use such tools in the wild. Birds belonging to the family Corvidae that include crows, ravens and rooks are known to possess higher intelligence.
The team also included researchers from University of Vienna and the Max Planck Institute and the study is published in the journal PLOS One.
Check a video of the experiment here.