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Can Pigeons Read?

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Much of modern research on animal “language” reminds me of a remark by one of my favorite comedians, Paul Lynde. Readers of a certain age may recall his snarky irreverent humor. He was asked once on a quiz show if it were possible to get a baby monkey to say “momma”? Lynde replied, “Give me a pair of pliers and a lit cigarette, and I’ll get him to say anything you want.”

Rather than pliers and cigarettes, researchers at Duke University are likely to have employed tasty treats for their research in a recent paper in PNAS, “Orthographic processing in pigeons.” The paper has stirred some excitement in the media:

Stop everything! It turns out pigeons can read

Don’t underestimate the pigeon — they might look a bit dim but it turns out these birds can actually read.

You won’t find pigeons scanning the latest Dan Brown book, but scientists have found they are the first non-primate species to distinguish certain words.

The National Academy of Sciences in Washington got the four smartest pigeons they could find and showed them 8,000 combinations of words and non-words.

The birds were then left with the challenge to peck the correct answers.

The clever things were even able to identify when the letters were transposed (like ‘very’ vs ‘vrey’).

By the end of the experiment, the feathered subjects had built vocabularies of between 26 and 60 words…

Psychologist Dr Damian Scarf, of Otago University in New Zealand, said: ‘The name of the game for the bird is if a word comes up it pecks the word — if a non-word or gibberish comes up then it pecks the star symbol.’

The actual scientific publication is a bit less breathless, but it’s important to understand exactly what the pigeons did and didn’t do. Here’s the “significance” claim of the authors:

A novel theory suggests that orthographic processing is the product of neuronal recycling, with visual circuits that evolved to code visual objects now co-opted to code words. Here, we provide a litmus test of this theory by assessing whether pigeons, an organism with a visual system organizationally distinct from that of primates, code words orthographically. Pigeons not only correctly identified novel words but also display the hallmarks of orthographic processing, in that they are sensitive to the bigram frequencies of words, the orthographic similarity between words and nonwords, and the transposition of letters. These findings demonstrate that visual systems neither genetically nor organizationally similar to humans can be recycled to represent the orthographic code that defines words.

Note first the gratuitous use of “evolved” in the opening sentence. The research has to do with training pigeons to recognize patterns, and has nothing to do with evolution. But the god of Natural Selection must be appeased (if you want your paper published), so it is de rigueur to toss an “evolved” into the discussion to get the paper past the border guards, like a forged passport. Homage must be paid.

The Abstract incudes:

[R]ecent research and theory suggest that orthographic processing may derive from the exaptation or recycling of visual circuits that evolved to recognize everyday objects and shapes in our natural environment. An open question is whether orthographic processing is limited to visual circuits that are similar to our own or a product of plasticity common to many vertebrate visual systems. Here we show that pigeons, organisms that separated from humans more than 300 million y ago, process words orthographically. Specifically, we demonstrate that pigeons trained to discriminate words from nonwords picked up on the orthographic properties that define words and used this knowledge to identify words they had never seen before.

After another pointless reference to evolution, the authors describe the training of pigeons to undertake “orthographic processing,” which refers to the ability to recognize the correct structure of written words. Of course it’s undeniable that pigeons and other animals can recognize shapes, including shapes printed in ink on paper. Shape recognition can be quite sophisticated in animals, who can distinguish all manner of predators and prey and food and shelter and the like. Using an adequate system of rewards, the birds can be trained to recognize shapes characteristic of letters printed on paper, and recognize patterns of shapes. The birds can also be trained to peck at representation of the patterns in different combinations:

In addition, the pigeons were sensitive to the bigram frequencies of words (i.e., the common co-occurrence of certain letter pairs), the edit distance between nonwords and words, and the internal structure of words. Our findings demonstrate that visual systems organizationally distinct from the primate visual system can also be exapted or recycled to process the visual word form.

There are two claims embedded in this research. One is that the ability of pigeons to recognize the shape of ink spots (words) provides meaningful insight into the evolution of language in humans. This is a flight of Darwinian fancy, but is not any real evidence and is nothing that should rightfully be called science. “Pigeons recognize shapes! Men write poetry! More evidence that men and pigeons evolved from a common ancestor!” Makes you slap your forehead.

The second claim is inherent in “pigeons [are] trained to discriminate words from nonwords…” What a load of bird-droppings. The researchers discriminated words from non-words, and trained the pigeons to peck at the shapes of ink that the researchers designated as words. The pigeons didn’t know words from worms. They have no language, and “words” mean nothing to them.

Shapes mean things to them, and with sufficient coaxing, they can be trained to peck at shapes selected by their trainers. And of course the “words they had never seen before” are merely shapes with partial resemblance (several similar letters) to shapes they had been rewarded to peck at in the past.

The pigeons did what pigeons do. They pecked at whatever shape got them treats. That isn’t reading, as Paul Lynde could have pointed out.

Now, in case you think that silly research and press hysteria like this are harmless, the press article includes this little factoid:

Although their brains are only the size of a thimble, pigeons apparently have similar levels of intelligence as those found in toddlers.

Earlier studies have shown they can tell the difference between live video images of themselves and previously recorded images.

This ability is higher than the average human three-year-old.

No one outside of a locked mental ward thinks that pigeons have the same (or higher!) intelligence than a three-year-old child. This junk science and junk journalism is used to equate human beings with animals and to deny human exceptionalism. Rest assured that this frightening trend will not result in increased respect and care for animals, but will most certainly result in decreased respect and care for human beings.

Image credit: © blueringmedia — stock.adobe.com.

Michael Egnor

Senior Fellow, Center for Natural & Artificial Intelligence
Michael R. Egnor, MD, is a Professor of Neurosurgery and Pediatrics at State University of New York, Stony Brook, has served as the Director of Pediatric Neurosurgery, and award-winning brain surgeon. He was named one of New York’s best doctors by the New York Magazine in 2005. He received his medical education at Columbia University College of Physicians and Surgeons and completed his residency at Jackson Memorial Hospital. His research on hydrocephalus has been published in journals including Journal of Neurosurgery, Pediatrics, and Cerebrospinal Fluid Research. He is on the Scientific Advisory Board of the Hydrocephalus Association in the United States and has lectured extensively throughout the United States and Europe.

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