When trained, crows can easily identify items by colour, shape and number of single samples as a matter of fact, that is as good as humans in terms of the so called ‘high order’ abstract reasoning process.
The findings show that birds are much smarter than previously thought. “The results shatter the notion that sophisticated forms of cognition can only be found in our ‘smart’ human species,” said Joel Fagot, director of research at the University of Aix-Marseille in France.
The study involved two 2-year-old hooded crows, which were trained to identify items by colour, shape and number of single samples. Soon they were able to identity matching-to-sample, helping researchers assess them with relational matching pairs of items.
These relational matching trials were arranged in such a way that neither test pairs precisely matched the sample pair, thereby eliminating control by physical identity. In a test the crows were supposed to choose two same-sized circles rather than two different-sized circles and they could perform the task of the relational matches that too so spontaneously, without explicit training.
“That is the crux of the discovery,” said corresponding author of the study Ed Wasserman, a psychology professor at University of Iowa in the US. “Honestly, if it was only by brute force that the crows showed this learning, then it would have been an impressive result. But this feat was spontaneous,” Wasserman pointed out.
With this discovery, crows join other animals like chimpanzees, apes, monkeys in terms of identifying similar objects by size or applying analogy. The study appeared in the journal Current Biology.