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   Science 
   
   This bird talks, counts, and reads - a little
   
   By David L. Chandler, Globe Staff, 05/18/98
   
   [INLINE] UCSON - It's not that he can correctly name objects, colors,
   and even materials that's most amazing about Alex. It's not even that
   he can count up to six objects.
   
   No, the most impressive accomplishment of this 22-year-old gray parrot
   is the way he's beginning to master the rudiments of reading.
   ''Sssssss,'' he sounds when his teacher, biologist Irene Pepperberg,
   shows him a red plastic S-shaped refrigerator magnet. When she pushes
   an H next to it, Alex promptly says ''Shhhhh.'' When she shows him the
   letters OR, Alex clearly enunciates ''or.''
   
   Alex is one smart bird.
   
   Not that he can say more words than other parrots. The record for
   that, according to the Guinness Book of Records, goes to Prudle, a
   gray parrot in England with a vocabulary of almost 800 words. Alex
   knows only about 100 words, but has a crucial edge over other parrots:
   When he says something, he means it. And he knows what he means.
   
   People had always assumed that parrots could only ''parrot'' words;
   they could mimic sounds but had no understanding of their meaning.
   Pepperberg carefully designed experiments to find out for sure. And
   after devoting 21 years to teaching Alex (and, more recently, two
   other gray parrots and one parakeet) and evaluating his language
   abilities, she has proved that to Alex, at least, the words really do
   have meaning.
   
   Holding a colored cloth ball in front of the bird, Pepperberg asks
   ''What matter?'' in the kind of laboratory Pidgin she uses to train
   her subjects. Alex - who can identify wood, plastic, metal and paper,
   among other ''matter'' - clearly says ''wool.'' Having answered
   correctly, he's entitled to a reward - but he has to ask for it.
   Unlike animals in conventional conditioning experiments, he gets
   nothing unless he asks for it by name, after having given a right
   answer to a question. ''Want a nut,'' he says, and then happily begins
   nibbling away at the cashew he is given.
   
   Next, Pepperberg presents him a tray that holds a jumbled mix of six
   green blocks, five green balls, three rose-colored balls, and four
   rose-colored blocks. She asks, ''How many rose block?'' After studying
   the tray, Alex will usually answer with the correct number - a task
   that requires not only counting ability but also an understanding of
   colors and shapes, and the ability to sort out the categories. (The
   numbers, types, and colors are changed each time, so he's not just
   memorizing).
   
   In other words, he has to do some serious thinking.
   
   Those abilities, comparable to the communicative abilities that other
   researchers have found in chimpanzees, gorillas, and dolphins, ''have
   surprised us,'' said Donald Griffin, a biologist who has taught at
   Harvard, Cornell and Rockefeller Universities and currently works at
   Harvard's Concord Field Station, an animal research facility.
   
   Such studies provided the initial inspiration for Pepperberg's work
   when she saw PBS's Nova program about dolphin and ape communication.
   The research is beginning to provide scientists with new insights
   about animals' mental capabilities. But this particular complex task
   that Alex mastered, counting and categorizing a mixture of objects, is
   one that no other non-human species has yet accomplished.
   
   Alex, however, does not always give the right answers; he's right
   about 80 percent of the time. But depending on his mood, some days he
   will give an incorrect answer every time - something he couldn't
   possibly do unless he knew the right answers, and just mischievously
   refused to give them.
   
   ''There's something going on that is not what you expect from
   animals,'' Pepperberg says. When he's being contrary, she suggests, he
   may be expressing frustration at ''so many years of tests and
   sessions'' by engaging in ''a little bit of game playing.''
   
   On a recent Sunday afternoon in Pepperberg's lab, Alex was unwilling
   to answer any tough questions. He normally gets the weekends off.
   While he showed great curiosity toward a newcomer in his domain, even
   climbing onto the visitor's hand and nibbling his thumb gently
   (''that's courtship behavior,'' Pepperberg pointed out), Alex was not
   about to give up his time off.
   
   According to a variety of standard tests, Alex and his fellow gray
   parrots, a species native to west-central Africa, have cognitive
   abilities comparable to a 4- or 5-year-old child, she says.
   Emotionally, however, they show ''all the negative, self-centered
   behavior of a 2- or 3-year old,'' she adds. ''That's why you have so
   many abandoned parrots.''
   
   For example, Griffin, the youngest of her three parrots, now has a
   bedraggled, moth-eaten look. He got that way while Pepperberg went
   away for a week and left the parrots in the care of her students.
   Griffin was so upset at being abandoned that he pulled out his
   feathers.
   
   Pepperberg, whose Harvard doctorate is in theoretical chemistry but
   whose career has been devoted to studying animal communication,
   documents all her work meticulously. She has published her results in
   respected, peer-reviewed scientific journals, something some animal
   communication researchers fail to do. Pepperberg is also cautious in
   how she characterizes her research subject's abilities.
   
   ''I never claim that he has language,'' she says of her star pupil
   Alex. ''You could never have the kind of conversation with him that
   you would have with another person - a two-way conversation. But he
   can tell us what he wants, and answer questions posed to him.''
   
   Until Pepperberg's ''sound and important work, we did not think that
   parrots could mean what they say,'' adds biologist Griffin, who has
   made a career of studying the abilities of animals.
   
   Griffin, author of the 1992 book ''Animal Minds,'' believes that such
   work can be valuable in helping humans understand the thought
   processes and feelings of non-human species. ''There is a way of
   getting at what are they thinking and feeling: Letting them tell us,''
   he said in an interview. While we know almost nothing about how
   animals, including parrots, communicate with each other in the wild,
   and what kinds of information they share, teaching them to speak and
   understand our language ''might be a very good entry wedge into it.''
   
   What does this research mean about what's going on inside Alex's
   brain? Pepperberg says that ''working with these birds for 20-some
   years, there's no question in my mind, on a personal level, that
   there's consciousness there. But I have not come up with any tests
   that I believe could show it.''
   
   Griffin agrees with that hunch. Some scientists are ''bashful about
   inferring conscious thinking, as I am not,'' he said. ''It's been a
   sort of no-no area to scientists.''
   
   In fact, Griffin has come up with a term for what he calls this
   ''curious reluctance'' of his colleagues to speak about animal
   consciousness: ''mentophobia.''
   
   Theodore Barber, a psychologist who heads the Research Institute for
   Interdisciplinary Science in Ashland, Mass., and wrote the 1993 book
   ''The Human Nature of Birds,'' is even more emphatic about bird
   consciousness. ''They're not robots or birdbrains,'' he said in an
   interview last week.
   
   After studying the published scientific research on birds' abilities,
   he said, ''I came to the conclusion that they're aware, they're
   intelligent, they know what they're doing.''
   
   In a recent paper in the Journal of Comparative Psychology, Pepperberg
   reported that young parrots develop certain mental abilities much like
   human children do. She demonstrated that Griffin, her youngest parrot,
   went through the same six stages that children do (and did so even
   faster) in developing a sense that objects still exist when they are
   hidden from view - what psychologist Jean Piaget called ''object
   permanence'' in his research with human children.
   
   Piaget showed that the ability to locate an object that is seen and
   then hidden is not an innate human ability, but is learned during the
   first two years of life. In the sixth stage, the experimenter hides an
   object inside a box (or a hand), hides the box under a cover, and then
   removes the box and shows it to be empty. The child determines that
   the object must now be under the cover - and so does the parrot.
   
   That's especially interesting because the same test has been tried on
   a wide variety of animals. Most never made it to stage six: Monkeys,
   cats, doves, chickens, and hamsters never figured it out. Only great
   apes, parrots, and possibly dogs passed the test. And the dogs did not
   get as far as Griffin did. They failed the most sophisticated test, a
   variant of the old shell game with an object placed under one of three
   covers that are then moved around.
   
   In the shell-game test, Pepperberg wrote in her analysis, Griffin
   ''never hesitated and seemed to track the experimenter's hand very
   closely,'' and he almost always knew where the object was. Alex, too,
   passed the test easily. That suggests, Pepperberg wrote, that ''gray
   parrots, unlike dogs and cats but like humans and great apes, develop
   a robust sense of object permanence.''
   
   According to Piaget, such abilities reflect a capacity to form a
   mental picture of an object, and to understand that its existence
   continues independent of the observer - fairly sophisticated abstract
   reasoning.
   
   But nobody has yet determined by rigorous scientific tests whether
   parrots, or any other species, develop more advanced concepts, such as
   a sense of self, or an ability to remember past events or look ahead
   to future events beyond the immediate fulfillment of simple requests.
   
   ''We have very little firm information'' about such mental abilities,
   biologist Griffin said. But those questions may eventually be
   answered: Research by Pepperberg and the handful of experimenters who
   are studying communication with apes and with dolphins are ''opening
   up a whole area where we used to think there was just nothing there.''
   
   Alex, however, has simpler things on his mind at the moment. Tiring of
   his visit with a stranger, he states his desire clearly: ''Want to go
   back.'' Is he thinking about going back to his cage, back to nature,
   or back to the African rainforests that were home to his ancestors?
   Probably not. He settles for going back to the table he left a few
   minutes ago, and eats another cashew.
   
   This story ran on page D01 of the Boston Globe on 05/18/98.
    Copyright 1998 Globe Newspaper Company.