Psychologist Irene Pepperberg tests Alex: “How many green blocks?”
Alex, age 23, and Griffin, age 4, are hell on decor. Thanks to them, the laboratory-cum-home of these impish African Grey parrots looks as if a miniature tornado has blown through. Strewn about are pieces of fruit from discarded snacks, mangled toys, and a huge mound of cardboard cartons demolished with great relish by Alex.
Psychologist Irene Pepperberg, the birds’ caretaker, maintains an amused tolerance about her two charges partly because they have richly rewarded her serious scientific inquiry into the intelligence of animals. For more than 20 years, her research has insistently challenged the idea that humans alone are capable of real thought and real language. In a series of experiments that withstand rigorous and even hostile scrutiny, Alex and Griffin have shown themselves intelligent enough to comprehend and juggle abstract images of the objects that make up their world—skills once thought to be the exclusive property of humans.
Under Pepperberg’s tutelage, the parrots have learned to speak English so clearly they’d delight even a fussy speech expert. But the value of this work goes far beyond experiments in voice training. These parrots aren’t just parroting—they associate specific words with specific objects, and they have learned to identify a number of different colors, shapes, and materials. Show Alex two triangles, one yellow and one blue, and ask him what’s the same about them. He’ll answer, “Shape.” Ask him what’s different, and he’ll say, “Color!”
Until Pepperberg began this research in the 1970s, few scientists had studied intelligence in parrots, and few do today. Most inquiries have instead focused on monkeys, chimpanzees, gorillas, and dolphins, all of which are much more difficult to raise, feed, and handle. Pepperberg especially likes parrots because, like humans, they’re smart, long-lived (often up to 50 years), social animals that depend on communication for survival. And, best of all, to communicate with people, parrots don’t need devices built with buttons to push, and they don’t need to be taught sign language: They speak plain English. Nobody knows why parrots can do this, or exactly how they do it. But they can clearly get their two cents in despite having a brain the size of a walnut.
Even the most skeptical visitor to Pepperberg’s lab is sure to be taken aback by what the birds can do. When Alex, for example, wants to visit a favorite atrium near the lab, he orders, “Go see tree!” And some of his communications are fresh—new words and phrases he hasn’t been taught. Once, for example, as two of his student trainers prepared to leave the lab at the end of a day, Alex admonished: “You be good. See you tomorrow!”
HOW TO TALK TO A PARROT
“The critical thing to understand is that these birds are extremely intelligent,” says Irene Pepperberg. “In the wild, they spend huge chunks of time breaking things open, looking for food, and they probably fly a couple of miles every day foraging. When they sit in a cage all day, it’s like putting a person in solitary confinement. Give them a big cage with interesting things in it; give them a lot of attention and a lot of supervised freedom.”
Sarah Wilcox and Alex model the teacher-student interaction for Thomas Firmage and Griffin. Sarah is asking Alex to repeat “truck.”
To train a parrot to talk, do not park yourself in front of it, robotically repeating “Hello.” The bird may eventually imitate you, but how can it know what the word means? Instead, Pepperberg advises, “Find a friend and invite her over for coffee and cake.” Then get to work. With the parrot observing, show the friend a key and say “key” at the same time.
It’s not just what they the parrots say that makes them seem eerily human; it’s the level of intelligence they easily demonstrate. Consider Griffin’s performance on a test Pepperberg devised to see whether the birds could use a mirror image of an object to manipulate it. Children don’t typically master that skill until they’re three years old. In the experiment, a nut is concealed underneath a lid on a box. The nut is attached to a wire that leads up through a slit in the lid and connects to a paper clip the parrot can yank. The slit branches out into three tracks, each of which ends in a hole through which the nut can be pulled. The trick is that two of the three slits are blocked by obstructions that can only be seen by looking in a mirror that reflects a backward view of what’s inside the box. Most humans who try to solve the puzzle are baffled, but Griffin, watching intently from his perch on the lab counter, might demand to be brought over, peer into the mirror for perhaps half a second, triumphantly zip the nut down the right track, jerk it up through the opening, and grab it.
Although Irene Pepperberg has always loved animals, she chose chemistry as her field in graduate school at Harvard University. There, in the early 1970s, she happened to see a television documentary about how animals learn. Like a number of researchers at the time, she became fascinated by the question of just how smart animals are and if they could learn to communicate with humans. While finishing up her chemistry degree, she began taking courses in animal behavior, psychology, and communication In 1977 she acquired one-year-old Alexl. he became the center of her research in a small lab at Purdue University.
Much of the animal-intelligence research of that era ultimately foundered before the onslaughts of skeptics. Most notable was Washoe, a chimpanzee who became world-famous for her apparent mastery of American Sign Language. But observers of Washoe objected that the researchers who worked with her were giving subtle cues and generously interpreting ambiguous gestures as signs for words. “It’s so easy to overinterpret when you have a bird that says, ‘I’ll see you tomorrow,’ ” says Pepperberg. “I’ve got enough anecdotal data like that to fill a book. But what’s really referential?” What, in other words, constitutes proof that the bird knows what it is saying? The history of science is littered with animals that seemed to be displaying extraordinary brainpower but were just responding to unconscious prompts from owners and trainers.
The parrot must use the mirror to see the reflection of the lid’s underside and thus figure out which slot to pull the nut reward through (left). Pepperberg is also teaching her parrots to identify the sounds of the alphabet (below). She wants to figure out if the birds can sound out words.
To avoid such pitfalls, Pepperberg designs experiments with the care of a hard-nosed skeptic. For example, when an experiment demands that Alex learn a new word like “none,” Pepperberg waits until the parrot’s pronunciation is so unambiguous that different observers agree 90 percent of the time on what he’s saying. That ensures that an experimenter eager for Alex to succeed won’t mishear a slurred random utterance as a right answer. She also strives to avoid the possibility that a correct response is merely conditioned—automatic behavior generated by the anticipation of a reward. So experimenters vary their repertoire of questions to make sure that Alex is responding to the content of the question and making intelligent discriminations. And to avoid the possibility that the experimenter’s body language might be prompting his answers, students who test Alex are never the same as those who taught him the words and concepts involved. As a result, Pepperberg’s work has won accolades for its persuasiveness from the likes of Oxford animal behaviorist Marian Stamp Dawkins, an authority on animal consciousness and a skeptic about many studies in the field.
Sometimes, human error offers the birds an opportunity to show how smart they are. Roughly 5 percent of the time, for example, student questioners slip up and scold Alex with a “No!” when he has in fact given the correct answer. When this occurs, Alex tends to stick to his guns and repeat the right answer. Eventually the examiner comes to her senses, and Alex gets the reward he deserves.