Photo by Jo McCulty, Ohio State University. Click here for additional images. |
COLUMBUS, Ohio - After a little more than three years' effort, psychologists at Ohio State University have taught a pair of young chimpanzees to "read" the names of nearly a dozen objects, to recognize the animals' own printed names and the names of tools they need to acquire their favorite foods.
In three more years, they hope to teach the animals to communicate in simple sentences.
That may seem a modest accomplishment -- giving a chimp a dozen-word vocabulary. But it is really a major step forward in a 20-year study of how these great apes learn, communicate and handle information. And at the end of this process, these animals may be able to use it to tell us - in their own words - about chimpanzee culture and society.
Sally Boysen, a professor of psychology at Ohio State, has spent more than two decades investigating how a colony of chimps at the university learn and communicate. Her latest work is the subject of an hour-long documentary, "Keeli & Ivy: Chimps Like Us," set to air Sunday night, April 14, 2002, (8 PM ET) on the Discovery Channel.
Aside from Boysen and her staff, the real stars of this program are two six-year old primates whose arrival at the OSU Chimpanzee Center gave researchers the chance to test this species' ability to process information sequentially. Humans excel at this ability and that, ostensibly, may set us apart from other animals.
It hasn't been clear, however, if this talent might possibly be established in chimps to teach them simple reading skills. While Boysen's work with nine other chimps over the years made great strides, part of the process of acculturating the animals to the research tasks has made testing this hypothesis difficult. With Keeli and Ivy, however, Boysen had a clean slate to work with.
"We knew from our earlier work in teaching the animals numbers and how to count that they had some ability to process information sequentially," Boysen said. "I wanted to look at a different symbolic representational system that would force the animals to construct abstract symbols in a sequence.
"I decided that teaching them English -- using reading, writing and constructing words based on alphabetic characters - would work nicely. It seemed to me that if we had chimps that were young enough, that they could learn to build that kind of system."
Years before, one of Boysen's other chimps, Bobby, had shown an uncanny ability to learn number sequences and even to fill in missing numbers in a sequence. The next step was to shift from numbers to letters and two-year-old Keeli and Ivy were at a perfect age to try.
"The idea was to start them with a sequential task while they were little so that they could 'build' a template that used the alphabet. We started with 'A,' then 'AB,' then 'ABC,' 'ABCD' and 'ABCDE' to give them the idea that the letters had an order to them," Boysen explained.
After the animals seemed to understand that, the researchers added simple three-letter words - "POP" (the chimps love orange soda), "KEY" (the cabinet where the soda is stored in the lab is locked with a key), and "CAT" (both chimps adored the housecats roaming the center, though while Keeli was affectionate and gentle, Ivy enjoyed teasing the animals).
But "building" even those simple words proved a slow and arduous task so Boysen shifted to "whole word recognition," temporarily abandoning the challenge of the chimps spelling out the words.
"It really helped to switch to using the whole words, " the researcher said.
"The chimps started learning things much more rapidly. We quickly introduced pictures of Keeli and Ivy and images of several of their other chimpanzee companions and their English names. Now we've added the names of certain tools - a stick and a sponge - that are functional in the animals daily lives." In the wild, chimpanzees use sticks to fish for termites that are out of reach, deep in dirt mounds. They also use wads of leaves to soak up water to drink. The sponge serves the OSU chimps as a surrogate for the leaves.
Boysen's team is teaching the two primates to use their limited vocabulary in different ways, such as making a request.
"Right now, they are using them (the words) functionally," she said. "They have to ask for a stick to reach pudding that is out of their reach, or for the sponge to soak up orange soda from a tube."
The pivotal question for the future, however, is whether the two young chimps can learn syntax - can they put the words together in novel combinations, as human children learn to do.
"We're being very careful to make sure that we don't impose any syntax or grammar on the animals as they learn to recognize English words," Boysen said. "We want to see if any patterns or regularities emerge in the animals rudimentary language that can tell us things about how they see themselves and their environment.
"I think we can use this approach to study the so-called 'theory of mind issues - how one chimpanzee perceives the state of mind of another," she said. Earlier work with her other chimps showed Boysen that the animals are able to detect whether another primate is aware of a possible, specific threat or reward.
Keeli's and Ivy's young age was key to the success so far with this project, which raises the question of whether there is a window in time, a sensitive period, when primates like these might be able to learn in this way.
"It's important that chimps have some types of learning experiences early in their lives, between birth and the age of three or four years old, just as these are the most important years for critical learning in human children," Boysen explained.
"But chimps won't be able to express their ideas or thoughts in as sophisticated a manner as children will eventually be able to do. That means that our challenge will be to be as creative as possible in trying to measure their true abilities.
"The only real limiting factor will probably be our own limitations in devising new ways to do just that," she said.
Contact: Sally Boysen, (614) 457-9259; Boysen.1@osu.edu
Written by Earle Holland, (614) 292-8384; Holland.8@osu.edu