Inside Animal Minds: The New Science of Animal Intelligence

I
n 1977, Irene Pepperberg, a recent graduate of Harvard University, did something very bold. At a time when animals still were considered automatons, she set out to find what was on another creature’s mind by talking to it. She brought a one-year-old African gray parrot she named Alex into her lab to teach him to reproduce the sounds of the English language. “I thought if he learned to communicate, I could ask him questions about how he sees the world.”

When Pepperberg began her dialogue with Alex, who died September 2007 at the age of 31, many scientists believed animals were incapable of any thought. They were simply machines, robots programmed to react to stimuli but lacking the ability to think or feel. Any pet owner would disagree. We see the love in our dog’s eyes and know that, of course, Spot has thoughts and emotions. But such claims remain highly controversial. Gut instinct is not science, and it is all too easy to project human thoughts and feelings onto another creature. How, then, does a scientist prove that an animal is capable of thinking—that it is able to acquire information about the world and act on it?

“That’s why I started my studies with Alex,” Pepperberg said. They
were seated—she at her desk, he on top of his cage—in her lab, a windowless room about the size of a boxcar, at Brandeis University. Newspapers lined the floor; baskets of bright toys were stacked on the shelves. They were clearly a team—and because of their work, the notion that animals can think is no longer so fanciful.

Certain skills are considered key signs of higher mental abilities: good memory, a grasp of grammar and symbols, self-awareness, understanding others’ motives, imitating others, and being creative. Bit by bit, in ingenious experiments, researchers have documented these talents in other species, gradually chipping away at what we thought made human beings distinctive while offering a glimpse of where our own abilities came from. Scrub jays know that other jays are thieves and that stashed food can spoil; sheep can recognize faces; chimpanzees use a variety of tools to probe termite mounds and even use weapons to hunt small mammals; dolphins can imitate human postures; the archerfish, which stuns insects with a sudden blast of water, can learn how to aim its squirt simply by watching an experienced fish perform the task. And Alex the parrot turned out to be a surprisingly good talker.

Thirty years after the studies with Alex began, Pepperberg and a changing collection of assistants were still giving him English lessons. The humans, along with two younger parrots, also served as Alex’s flock, providing the social input all parrots crave. Like any flock, this one—as small as it was—had its share of drama. Alex dominated his fellow parrots, acted huffy at times around Pepperberg, tolerated the other female humans, and fell to pieces over a male assistant who dropped by for a visit. (“If you were a man,” Pepperberg said, after noting Alex’s aloofness toward me, “he’d be on your shoulder in a second, barfing cashews in your ear.”)

Pepperberg bought Alex in a Chicago pet store. She let the store’s assistant pick him out because she didn’t want other scientists
saying later that she’d deliberately chosen an especially smart bird for her work. Given that Alex’s brain was the size of a shelled walnut, most researchers thought Pepperberg’s interspecies communication study would be futile.

“Some people actually called me crazy for trying this,” she said. “Scientists thought that chimpanzees were better subjects, although, of course, chimps can’t speak.”

Chimpanzees, bonobos, and gorillas have been taught to use sign language and symbols to communicate with us, often with impressive results. The bonobo Kanzi, for instance, carries his symbol-communication board with him so he can “talk” to his human researchers, and he has invented combinations of symbols to express his thoughts. Nevertheless, this is not the same thing as having an animal look up at you, open his mouth, and speak.

Pepperberg walked to the back of the room, where Alex sat on top of his cage preening his pearl gray feathers. He stopped at her approach and opened his beak.

“Want grape,” Alex said.

“He hasn’t had his breakfast yet,” Pepperberg explained, “so he’s a little put out.”

Alex returned to preening, while an assistant prepared a bowl of grapes, green beans, apple and banana slices, and corn on the cob.

Under Pepperberg’s patient tutelage, Alex learned how to use his vocal tract to imitate almost one hundred English words, including the sounds for all of these foods, although he calls an apple a “ban-erry.”

“Apples taste a little bit like bananas to him, and they look a little bit like cherries, so Alex made up that word for them,” Pepperberg said.

Alex could count to six and was learning the sounds for seven and eight.

“I’m sure he already knows both numbers,” Pepperberg said.
“He’ll probably be able to count to ten, but he’s still learning to say the words. It takes far more time to teach him certain sounds than I ever imagined.”

After breakfast, Alex preened again, keeping an eye on the flock. Every so often, he leaned forward and opened his beak: “Ssse … won.”

“That’s good, Alex,” Pepperberg said. “Seven. The number is seven.”

“Ssse … won! Se … won!”

“He’s practicing,” she explained. “That’s how he learns. He’s thinking about how to say that word, how to use his vocal tract to make the correct sound.”

It sounded a bit mad, the idea of a bird having lessons to practice, and willingly doing it. But after listening to and watching Alex, it was difficult to argue with Pepperberg’s explanation for his behaviors. She wasn’t handing him treats for the repetitious work or rapping him on the claws to make him say the sounds.

“He has to hear the words over and over before he can correctly imitate them,” Pepperberg said, after pronouncing “seven” for Alex a good dozen times in a row. “I’m not trying to see if Alex can learn a human language,” she added. “That’s never been the point. My plan always was to use his imitative skills to get a better understanding of avian cognition.”

In other words, because Alex was able to produce a close approximation of the sounds of some English words, Pepperberg could ask him questions about a bird’s basic understanding of the world. She couldn’t ask him what he was thinking about, but she could ask him about his knowledge of numbers, shapes, and colors. To demonstrate, Pepperberg carried Alex on her arm to a tall wooden perch in the middle of the room. She then retrieved a green key and a small green cup from a basket on a shelf. She held up the two items to Alex’s eye.

“What’s same?” she asked.

Without hesitation, Alex’s beak opened: “Co-lor.”

“What’s different?” Pepperberg asked.

“Shape,” Alex said. His voice had the digitized sound of a cartoon character. Because parrots lack lips (another reason it was difficult for Alex to pronounce some sounds, such as ba), the words seemed to come from the air around him, as if a ventriloquist were speaking. But the words—and what can only be called the thoughts—were entirely his.

For the next 20 minutes, Alex ran through his tests, distinguishing colors, shapes, sizes, and materials (wool versus wood versus metal). He did some simple arithmetic, such as counting the yellow toy blocks among a pile of mixed hues.

And, then, as if to offer final proof of the mind inside his bird’s brain, Alex spoke up. “Talk clearly!” he commanded, when one of the younger birds Pepperberg was also teaching mispronounced the word
green
. “Talk clearly!”

“Don’t be a smart aleck,” Pepperberg said, shaking her head at him. “He knows all this, and he gets bored, so he interrupts the others, or he gives the wrong answer just to be obstinate. At this stage, he’s like a teenage son; he’s moody, and I’m never sure what he’ll do.”

“Wanna go tree,” Alex said in a tiny voice.