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- LONDON - An African gray
parrot called Alex has been stretching the definition of animal intelligence.
Talking is a talent shared by many parrots, but unlike most others, Alex
talks to some purpose. After 22 years of training by Irene Pepperberg,
professor of biology at the University of Arizona in Tucson, Alex has acquired
skills that appear well beyond the normal abilities of a bird.
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- He can recognize 50 different objects, distinguish numbers
up to six, recognize seven colors and five shapes, and understand concepts
such as bigger, smaller, same and different. This puts him in a category
of animal intelligence previously aspired to only by chimpanzees and dolphins.
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- Professor Pepperberg was recently in London to speak
at a meeting organized by the Association for the Study of Animal Behaviour,
and is publishing a book, The Alex Studies, with the Harvard University
Press this spring. Her work with Alex raises again the question of whether
animals are capable of abstract thought.
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- "Emotionally, parrots behave like spoilt 2-year-olds,"
she told Gail Vines in an interview in New Scientist. "But intellectually,
Alex has gone a whole lot further " he's up there with chimps and
dolphins. He's doing the same tasks. It's remarkable. After all, chimps
are genetically 98.5 percent identical to human beings yet here is a bird
that, evolutionarily speaking, is way off in left field."
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- The most difficult tasks Alex can accomplish are tests
of comprehension, when he is shown a tray of objects of different shapes,
colors and materials. He will correctly answer when asked, for example,
how many are red, or asked to find an object that is yellow and three-cornered.
When asked what color corn is, he answers yellow.
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- These results certainly suggest that Alex has an abstract
concept of what the words mean, rather than simply memorizing them. But
Dr. Pepperberg carefully avoids any claim that he has learned language,
reluctant to be drawn into a long-running and sometimes bitter argument
about the language abilities of animals. What little syntax he has learned
is very simple, she says.
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- She has had a long struggle to be taken seriously. She
bought Alex from a pet shop after being inspired by a TV documentary about
chimps which had learned sign language, and started applying for research
grants. She eventually got one, and started to train him using a technique
first developed by the German biologist Dietmar Todt.
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- This involves asking a second person to carry out the
tasks while the parrot watches. By watching the interaction, the bird learns
to associate the command with the response, rather than merely learning
to associate it with a reward, as in classical conditioning. The idea is
to mimic the way parrots learn in the wild by watching their peers and
their parents.
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- Dr. Herbert Terrace of Columbia University, who in the
1970s showed that chimps could be taught words, but not language, acknowledges
that Alex is a clever bird. But he believes that his responses, intelligent
as they appear, are just a rote response triggered by a cue from his trainers.
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