According to a new study by University of Otago researchers, pigeons (Columbidae) can learn to distinguish real words from non-words by visually processing their letter combinations.
The researchers, led by Dr. Damian Scarf of the University of Otago’s Department of Psychology, trained rock pigeons (Columba livia, not to be confused with Streptopelia decaocto from the photo) 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 found that the pigeons' performance was on a par with that previously reported in baboons for this type of complex task.
Dr. Damian Scarf and his colleagues 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 memorizing them, they introduced words the birds had never seen before.
The pigeons correctly identified the new words as words at a rate significantly above chance.
Co-author Prof. Onur Güntürkün, from the Department of Biopsychology at the Ruhr-University Bochum, Germany, 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," added study senior author Prof. Michael Colombo, from the University of Otago’s Department of Psychology.