Inside the Animal Mind

Birds may have a reputation for being less than geniuses, but researchers are discovering that some are remarkably smart. Ravens, for instance, have the ability to solve difficult puzzles, such as untangling a knotted string to free up a tasty treat or figuring out how to steal fish by hauling in an angler's untended line. And, as shown in "Are Animals Intelligent?," the first part of NATURE's INSIDE THE ANIMAL MIND, crows on the remote Pacific island of New Caledonia have learned a skill that people once thought only primates could master: the use of tools. The birds use long, specially chosen twigs to spear the plump grubs that hide deep beneath the bark of rotting logs.

Raven antics and New Caledonia's clever crows have helped make people much more willing to admit that many animals, including birds, are quite intelligent. Dolphins can follow complex instructions, for instance, while orangutans learn complex tasks, such as washing clothes by hand, after just a few tries. And even pigeons and parrots have shown an extraordinary capacity to recognize, count, or name different objects.

But no bird has done more to give a whole new meaning to the phrase "birdbrain" than Alex the African Grey parrot. More than 20 years ago, researcher Dr. Irene Pepperberg of the University of Arizona began systematically studying Alex and several other African Greys, parrots that are remarkable mimics, to understand avian intelligence. "Before I began my studies, I knew that parrots could reproduce the sounds of human speech, but that the general belief was that such vocalizations could not be meaningful," Pepperberg has written. Today, her work with Alex has challenged that notion. For instance, Alex can name more than 40 objects and understands the concepts of "same" and "different," "absence," "quantity," and "size." Alex, Pepperberg says "has mastered tasks once thought to be beyond the capacity of all but humans or certain non-human primates."

Happiness, sadness, anger, fear, love, hate-emotions play a pivotal role in our lives. But do they loom large in an animal's world as well? Part Two of NATURE's INSIDE THE ANIMAL MIND, "Do Animals Have Emotions?," explores that question in fascinating detail.

In large part, researchers have found that emotions are accompanied by biochemical changes in the brain. Fear, for instance, is accompanied by the production of one set of brain chemicals that can make us alert and ready to flee, while pleasure triggers the release of other chemicals that soothe and calm. But some emotions aren't so biologically clear-cut. Shame, for instance, is a so-called "social emotion," the product of attaching an emotional meaning to a behavior, such as hitting another person, or lying, that may be appropriate in one social setting but out of bounds in another. While researchers don't agree on how big a role such social emotions play in the animal world, there is widespread agreement that many animals share another emotional characteristic with us: stress. Indeed, like humans, many animals can be harried and "stressed out"-with sometimes serious health consequences.

Among the most remarkable studies of stress in animals are those carried out on African baboons by Stanford University research Robert Sapolsky and his colleagues. For three months each year, Sapolsky travels to East Africa's Serengeti plain to examine how factors like a baboon's social behavior, personality, and rank within its troop influence the levels of stress hormones produced by the ape. By measuring the hormones found in each individual's feces, Sapolsky's team has been able to show that baboon troops are high-stress societies, with higher-ranked individuals maintaining order by intimidating lower-ranked troopmates. Indeed, Sapolsky says, "Baboons and us are surprisingly similar . . . they can devote a large part of each day to making each other absolutely miserable with social stress."

Sapolsky's team has also shown that such stress can have real health consequences. Stressed-out mothers, for instance, have more problems producing healthy offspring. And sustained production of stress hormones can also damage the hippocampus, a region of the brain central to learning and memory. So even though baboons may not commute, do their bosses' dry cleaning, or pay income taxes, they suffer very similarly from the scourge of stress.

As you read this, you are probably aware of reading this. Indeed, you can also imagine yourself reading this-a sort of picture within a picture in your mind's eye.

But do animals share this kind of consciousness? That is the question asked by Part Three of NATURE's INSIDE THE ANIMAL MIND, "Animal Consciousness." The program ponders just what consciousness is-and which animals might share this trait with people.

Bees, for instance, appear to meet one of the requirements for consciousness. They can create "mental maps," images they hold in their minds that allow them to navigate around their environments by picturing themselves there. Chimps and elephants appear to exhibit another consciousness trademark: an awareness of death. Both animals grieve when family members die: elephants even linger over the bones of long-dead relatives, seeming to ponder the past and their own future. But are these behaviors enough to give bees, chimps, and elephants membership in the consciousness club?

Researchers are actively debating the answer to that question. "Consciousness is one of the hardest things to define and study," says Pete Chernika, an Austrian researcher who has studied consciousness in dolphins and other animals. "In experiments, for instance, dolphins appear to pass one consciousness test by recognizing themselves in mirrors. And dolphins also exhibit a keen awareness of the status and identity of other dolphins in their highly social groups, he says.They know who mom is, who the leaders of the pod are, and how they should behave around different individuals," he says. "They appear to be able to envision themselves in relation to all these other animals and then act accordingly."

Indeed, many researchers believe consciousness is more likely in highly social animals such as chimps and dolphins, who must be able to see themselves in relation to others in their groups in order to get along. "Complex social interaction puts a high priority on awareness of self and others," says Chernika. But he warns that the more people study other animals, the more we realize how hard it is to define consciousness-and how hard it is to decide who has it, and who doesn't.

We recommend these Web sites for those interested in the subjects shown on the program. All links are valid as of January 3, 2000.

Think Tank at the National Zoo
An unusual exhibit concerned with animal thinking, from insects to orangutans.


Communication with Parrots
Discusses Dr. Irene Pepperberg's work with Alex, the famous African Grey parrot.


Baboons: High Anxiety Lowers the Birth Rate
An account of how stress impairs baboons, from NEW SCIENTIST.

The Intelligence of Dogs
Which breeds are most intelligent? A ranking from neurologist Stanley Coren.


Crows and Ravens: Birds of Mystery and Intrigue
Extensive information about these remarkably clever birds from Troy Karki.