Pigeons can learn to distinguish real English words from non-words, according to a new study which showed that the performance of the birds was on par with that seen in baboons for this type of complex task.
The study from University of Otago in New Zealand and Ruhr University in Germany is the first to identify a non-primate species as having “orthographic” abilities.
In the experiment, pigeons were trained to peck four-letter English words as they came up on a screen, or to instead peck a symbol when a four-letter non-word, such as “URSP” was displayed.
The researchers added words one by one with the four pigeons in the study eventually building vocabularies ranging from 26 to 58 words and over 8,000 non-words.
To check whether the pigeons were learning to distinguish words from non-words rather than merely memorising them, the researchers introduced words the birds had never seen before.
The pigeons correctly identified the new words as words at a rate significantly above chance.
According to Damian Scarf of the University of Otago, they performed this feat by tracking the statistical likelihood that “bigrams” – letter pairs such as ‘EN’ and ‘AL’, were more likely associated with words or non-words.
Onur Gunturkun, from Ruhr University, said “that pigeons – separated by 300 million years of evolution from humans and having vastly different brain architectures – show such a skill as orthographic processing is astonishing.”
“We may have to seriously re-think the use of the term ‘bird brain’ as a put down,” said Professor Michael Colombo of University of Otago.
The study was published in the journal PNAS.