Azy, a 250-pound orangutan, lumbers into a glass-enclosed lab room and settles onto a shelf in front of two monitors. The first screen blinks and displays three abstract symbols, while a photo of an apple takes shape on the second. When there's a knock on the glass plane, Azy turns to see a researcher waving an apple slice.
Azy turns back to the computers and lifts a banana-sized finger midair. And pauses.
And jabs a finger at one of the symbols -- a box with a diagonal line, which in fact represents "apple."
Researchers at the National Zoo in Washington are interested in Azy's accuracy and -- more importantly -- in that pause. Azy's hesitation is somehow familiar to us. Rob Shumaker, head of the orangutan language project here, suggests that in that pause the orangutan is weighing his options. That is, that Azy and other great apes indeed think.
Philosophers have debated animal cognition for centuries. Aristotle called serpents crafty. Medieval villagers tried and executed dogs and pigs for premeditated bitings and murders. For most of the 20th century, scientific thought on the subject has been dominated by behaviorism -- the theory that all animal behavior is the product of conditioning. Problem-solving and adaptability were considered exclusively human skills.
But studies in recent decades have cast doubt on that model.
Frans de Waal, a professor of primate behavior at Emory University and researcher at the university's Yerkes Primate Regional Research Center, says behaviorism now is considered the first, not the final word: "When we can't explain a reaction through conditioning, that's when we start to think maybe something else is going on."
The content of that "something else" -- an animal's cognitive world -- and the methods by which humans can best observe it, are far from settled. How, for example, can "thoughtful" behavior be distinguished from conditioned or instinctual responses?
Shumaker believes the National Zoo has an answer. He helped develop the Zoo's definition of thinking for an exhibit called Think Tank, which allows the public to watch his research. Thinking, he suggests, involves intention, flexibility and the creation of a mental image.
Shumaker points to all three skills in Azy's computer performance: The orangutan has the intention to choose the apple symbol, the flexibility to choose the correct symbol (even as its size and placement vary) and the ability to envision the apple when he is shown a photographic image or plastic model of the fruit. "There's no way I could have conditioned him to do this," Shumaker says.
After a year and a half in the program, Azy knows only seven symbols, but Shumaker is not discouraged. Researchers who taught animals language two decades ago marveled at how many symbols their animal pupils could remember, but today's language studies attempt to observe the animal's depth of understanding. It is less important to Shumaker that Azy remembers seven symbols than it is that the orangutan displays the three "thoughtful" skills.
Some primate specialists argue this is still not true thinking. Azy's use of symbols is akin to gluing wings on a human to see if he can fly, says Daniel J. Povinelli, a researcher at the University of Southwestern Louisiana. "Animals do seem to grasp the symbols, but they don't seem to grasp that the symbols are a communicative device, and why should they?" he says. "Language is a human construct."
Povinelli studies chimpanzee's self-awareness by observing the chimps' reactions to themselves in mirrors and their interactions with other animals and with humans. "I've always favored approaches which create understandable scenarios for the animal, research that lets the animals resolve their own problems," he says. "I'm interested in knowing who chimps are, not who we want them to be."
Terrence W. Deacon, whose book "The Symbolic Species: The Co-Evolution of Language and the Brain" contrasts the language skills of humans with that of primates, says insights can be gleaned from teaching primates language as long as expectations are low.
An anthropologist at Boston University, Deacon says all species have a "learning bias." Humans, he says, have acquired a propensity for symbolic language through evolution; people grew reliant on spoken language and therefore developed a genetic disposition to learn symbols quickly. Animals never had a need for a symbolic communication system. So their brains developed without that disposition -- and animals therefore have tremendous difficulty learning language.
Deacon says the great apes are able to learn the concept that symbols are a communication system, but teaching them takes much longer than it does to teach a human child the same idea. "It's not a matter of intelligence," he says. "It's about evolution. It's not that we're smarter than they are, it's that we both have a learning bias."
Deacon says that with patience humans can learn from the learning process itself.
"We shouldn't try to find out how much they remember. If we want insight into their thinking process, we need to study how they learn and how they overcome the fact that to them, language communication is counter-intuitive."
Other researchers argue cognition is revealed in the animals' daily natural interactions. Frans de Waal, the primate specialist from Emory, says the best insights come from watching the great apes frolic or fight.
Empathy and kindness
De Waal has written extensively on the evidence of empathy and kindness shown in daily primate interaction. He says that empathy explains the actions of Binti Jua, the female gorilla at the Brookfield Zoo near Chicago who stunned zoo keepers last summer when she comforted a human toddler who fell into the gorilla pen, then delivered the baby to safety.
And de Waal's theories speak to the experience that startled Shumaker eight years ago and solidified his conviction that orangutans are thoughtful beings:
A full-grown female orangutan named Bonnie was protecting her sick baby in their mesh-covered enclosure at the National Zoo. Keepers knew the baby orangutan needed medication, but expected the mother to become defensive, even violent if a human approached their cage.
Shumaker tried anyway.
Bonnie did not attack. She instead lifted the baby and gently pushed him against the mesh fence. Shumaker was able to stick the hypodermic needle through the fence and vaccinate the baby, while Bonnie firmly held the young orangutan.
"It was clear she understood what was going on," Shumaker says. "After that I had no question about their cognitive skills."
Pub Date: 6/08/97