Alex is a 28-year-old grey parrot who lives in a lab at Brandeis University in Waltham, Mass., and can count, identify objects, shapes, colors and materials. And now, Alex has grasped the concept of zero, according to World Science. In fact, Alex can describe the absence of a numerical quantity on a tray containing colored cubes. When a color is missing, Alex consistently identified this "zero quantity" by saying "none." You might think that this is just a parrot trick, but this research about 'bird intelligence' might also help autistic and other learning-disabled children "who have trouble learning language and counting skills." Read more.
One of the really interesting things about Alex is that it had learned in the past that "none" meant a lack of information. And without any training, when Alex was asked to say how many green or red cubes were on a tray in front of him, he spontaneously said "none" when there was no cubes with this color. In fact, he was able to connect two different concepts, a lack of information and the absence of a quantity. Pretty brilliant parrot, isn't?
Before going further, below is a picture of Alex in front of his counting blocks (Credit: Brandeis University). And here is a link to a larger version (193 KB).
Now, let's look at how the researchers made the discovery that Alex possessed a "zero-like concept."
The story began when researchers started testing Alex to see whether he understood small numbers, between one and six. Zero wasn't expected of him. The researchers would lay out an array of objects of different colors and sizes, and asked questions such as "what color four?" -- meaning which color are the objects of which there are four.
Apparently, Alex was pretty good on these tests, until he got bored. So the researchers "found some more interesting toys to give as rewards." And here came the decisive experiment.
One of these apparent lapses occurred one day when an experimenter asked Alex "what color three?" Laid out before Alex were sets of two, three and six objects, each set differently colored. Alex insisted on responding: "five." This made no sense given that the answer was supposed to be a color.
After several tries the experimenter gave up and said: "OK, Alex, tell me: what color five?" "None," the bird replied. This was correct, in that there was no color that graced exactly five of the objects. The researchers went on to incorporate "none" into future trials, and Alex consistently used the word correctly, they said.
My smiling child
Named for a noble ancestor
Great hunter or warrior
You will be one day.
Which will give your papa pride
But always I will remember you thus.
—African Lullaby. As quoted in Roots, by Alex Haley (1976)
A few days after this article was published, Brandeis University decided to issue a press release adding that Alex was the "first bird to comprehend numerical concept akin to zero."
"It is doubtful that Alex's achievement, or those of some other animals such as chimps, can be completely trained; rather, it seems likely that these skills are based on simpler cognitive abilities they need for survival, such as recognition of more versus less," explained comparative psychologist and cognitive scientist Dr. Irene Pepperberg.
Dr. Pepperberg's research, which uses a training method called the model-rival technique, also holds promise for teaching autistic and other learning-disabled children who have difficulty learning language, numerical concepts and even empathy.
So far, results using this learning technique with small groups of autistic children have been very promising.
The latest research work about Alex and his comprehension of zero has been published by the Journal of Comparative Psychology in its May 2005 issue (Volume 119, Issue 2) under the name "Number Comprehension by a Grey Parrot (Psittacus erithacus), Including a Zero-Like Concept." You'll get to the abstract from this page (scroll to number #8).
A Grey parrot (Psittacus erithacus) that was able to quantify 6 item sets (including subsets of heterogeneous groups, e.g., blue blocks within groupings of blue and green blocks and balls) using English labels was tested on comprehension of these labels, which is crucial for numerical competence. He was, without training, asked "What color/object [number]?" for collections of various simultaneously presented quantities (e., subsets of 4, 5, and 6 blocks of 3 different colors; subsets of 2, 4, and 6 keys, corks, and sticks). Accuracy was greater than 80% and was unaffected by array quantity, mass, or contour. His results demonstrated numerical comprehension competence comparable to that of chimpanzees and very young children. He also demonstrated knowledge of absence of quantity, using "none" to designate zero.
For more information, you can buy this article for $11.95.
Finally, if you still want to know more about Irene Pepperberg's work with gray parrots, you can visit the Alex Foundation, where you'll find that someday, Alex may be able to read. Amazing.
Sources: World Science, July 2, 2005; and various web sites
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