Monday, December 17, 2007

Baboon Metaphysics: Tabula Rasa and Group IQ

I recently came across this free excerpt from the Baboon Metaphysics: The Evolution of a Social Mind. From the excerpt the book seems very promising.

First, let me tell you how, the book got its name. It got its name from a quote by Darwin, while he was contemplating the debate between empiricists (we gain knowledge from experiences- tabula rasa) and rationalists (we have innate schema, intuition and logic that is independent of experiences) as to how we acquire knowledge, and how evolutionary theory might provide the answers.

With growing excitement, Darwin began to see that his theory might allow him to reconstruct the evolution of the human mind and thereby resolve the great debate between rationalism and empiricism. The modern human mind must acquire information, organize it, and generate behavior in ways that have been shaped by our evolutionary past. Our metaphysics must be the product of evolution. And just as the key to reconstructing the evolution of a whale’s fin or a bird’s beak comes from comparative research on similar traits in closely related species, the key to reconstructing the evolution of the human mind must come from comparative research on the minds of our closest animal relatives. “He who understands baboon would do more towards metaphysics than Locke.”

The authors then go on to confront behaviorist thoughts with experimental results that show that many animals come pre-programed in this world.

Song sparrows (Melospiza melodia) and swamp sparrows (Melospiza georgiana) are two closely related North American birds with very different songs. Males in both species learn their songs as fledglings, by listening to the songs of other males. But this does not mean that the mind of a nestling sparrow is a blank slate, ready to learn virtually anything that is written upon it by experience. In fact, as classic research by Peter Marler and his colleagues has shown, quite the opposite is true. If a nestling male song sparrow and a nestling male swamp sparrow are raised side-by-side in a laboratory where they hear tape-recordings of both species’ songs, each bird will grow up to sing only the song of its own species.

The constraints that channel singing in one direction rather than another cannot be explained by differences in experience, because each bird has heard both songs. Nor can the results be due to differences in singing ability, because both species are perfectly capable of producing each other’s notes. Instead, differences in song learning must be the result of differences in the birds’ brains: something in the brain of a nestling sparrow prompts it to learn its own species’ song rather than another’s. The brains of different species are therefore not alike. And the mind of a nestling sparrow does not come into the world a tabula rasa—it arrives, instead, with genetically determined, inborn biases that actively organize how it perceives the world, giving much greater weight to some stimuli than to others. One can persuade a song sparrow to sing swamp sparrow notes, but only by embedding these notes into a song sparrow’s song. It is almost impossible to persuade a swamp sparrow to sing any notes other than its own. Philosophically speaking, sparrows are Kantian rationalists, actively organizing their behavior on the basis of innate, preexisting schemes.

They then go on to discuss studies by Tolman and his students that gave a blow to behaviorism and introducing knowledge as an intermediary between stimulus and response.

In 1928, Otto L. Tinklepaugh, a graduate student of Tolman’s, began a study of learning in monkeys. His subjects were several macaques who were tested in a room in the psychology department at the University of California at Berkeley (sometimes the tests were held outdoors, on the building’s roof, which the monkeys much preferred). In one of Tinklepaugh’s most famous experiments, a monkey sat in a chair and watched as a piece of food—either lettuce or banana—was hidden under one of two cups that had been placed on the floor, six feet apart and several feet away. The other cup remained empty. Once the food had been placed under the cup, the monkey was removed from the room for several minutes. Upon his return, he was released from the chair and allowed to choose one of the cups. All of Tinklepaugh’s subjects chose the cup hiding the food, though they performed the task with much more enthusiasm when the cup concealed banana.

To illustrate the difference between behaviorist and cognitive theories of learning, pause for a moment to consider the monkey as he waits outside the experimental room after seeing, for example, lettuce placed under the left-hand cup. What has he learned? Most of us would be inclined to say that he has learned that there is lettuce under the left-hand cup. But this was not the behaviorists’ explanation. For behaviorists, the reward was not part of the content of learning. Instead, it served simply to reinforce or strengthen the link between a stimulus (the sight of the cup) and a response (looking under). The monkey, behaviorists would say, has learned nothing about the hidden food—whether it is lettuce or banana. His knowledge has no content. Instead, the monkey has learned only the stimulus-response associations, “When you’re in the room, approach the cup you last looked at” and “When you see the cup, lift it up.” Most biologists and laypeople, by contrast, would adopt a more cognitive interpretation: the monkey has learned that the right-hand cup is empty but there is lettuce under the left-hand cup.

To test between these explanations, Tinklepaugh first conducted trials in which the monkey saw lettuce hidden and found lettuce on his return. Here is his summary of the monkey’s behavior:

Subject rushes to proper cup and picks it up. Seizes lettuce. Rushes away with lettuce in mouth, paying no attention to other cup or to setting. Time, 3–4 seconds.

Tinklepaugh next conducted trials in which the monkey saw banana hidden under the cup. Now, however, Tinklepaugh replaced the banana with lettuce while the monkey was out of the room. His observations:

Subject rushes to proper cup and picks it up. Extends hand toward lettuce. Stops. Looks around on floor. Looks in, under, around cup. Glances at other cup. Looks back at screen. Looks under and around self. Looks and shrieks at any observer present. Walks away, leaving lettuce untouched on floor. Time, 10–33 seconds.

It is impossible to escape the impression that the duped monkey had acquired knowledge, and that as he reached for the cup he had an expectation or belief about what he would find underneath. His shriek reflected his outrage at this egregious betrayal of expectation.

Later they move on to their central premise, that baboons offer a good model to study the evolution of (human) mind.

Moreover, the conservation status of baboons confers neither glamour nor prestige on those who study them. Far from being endangered, baboons are one of Africa’s most successful species. They flourish throughout the continent, occupying every ecological niche except the Sahara and tropical rain forests. They are quick to exploit campsites and farms and are widely regarded as aggressive, destructive, crop-raiding hooligans. Finally, baboons are not particularly good-looking—many other monkeys are far more photogenic. Indeed, through the ages baboons have evoked as much (if not more) repulsion than admiration.

Baboons are interesting, however, from a social perspective. Their groups number up to 100 individuals and are therefore considerably larger than most chimpanzee communities. Each animal maintains a complex network of social relationships with relatives and nonrelatives—relationships that are simultaneously cooperative and competitive. Navigating through this network would seem to require sophisticated social knowledge and skills. Moreover, the challenges that baboons confront are not just social but also ecological. Food must be found and defended, predators evaded and sometimes attacked. Studies of baboons in the wild, therefore, allow us to examine how an individual’s behavior affects her survival and reproduction. They also allow us to study social cognition in the absence of human training, in the social and ecological contexts in which it evolved.

This same theme, of baboons having a greater social/group IQ is also touched upon by fellow ScientificBlogger Howard Bloom in a series of fascinating articles at the, where I also blog. specifically Bloom refers to baboons and how they are smarter than chimpanzees, by being able to adapt to any environment (a more plausible definition of intelligence, instead of the usual anthropomorphic one we are accustomed to).

The ultimate test of intelligence is adaptability—how swiftly you can solve a complex problem, whether that problem is couched in words, in images, in crises, or in everyday life. The arena where intelligence is most important is not the testing room, it’s the real world. When you measure adaptability by the ability to turn disasters into opportunities and wastelands into paradises, bacteria score astonishingly high. But how do big-brained chimpanzees and small-brained baboons do? Or, to put it differently, how adaptable, clever, mentally agile, and able to solve real-world problems have chimpanzees and baboons proven to be?

He illustrates the above with a real world field study case example that showed the high adaptability of baboons.

Baboons have been called “the rats of Africa.” No matter how badly you desecrate their environment, they find a way to take advantage of your outrage. One group, the Pumphouse Gang, was under study for years by primatologist Shirley Strum. When Strum began her baboon-watching, the Pumphouse Gang lived off the land in Kenya and ate a healthy, all-natural diet. They ate blossoms and fruits when those were in season. When there were no sweets and flowery treats, the baboons dug up roots and bulbs.

Then came disaster—the meddling of man. Farmers took over parts of the baboons’ territory, plowed it, built houses, and put up electrified fences around their crops. Worse, the Kenyan military erected a base, put up homes for the officers’ wives and kids, and trashed even more of the baboons’ territory by setting aside former baboon-land for a giant garbage heap. If this had happened to a patch of forest inhabited by chimps, the chimpanzee tribes would have been devastated. But not the baboons.

At first, the Pumphouse Gang maintained its old lifestyle and continued grubbing in the earth for its food. Then came a new generation of adolescents. Each generation of adolescent baboons produces a few curious, unconventional rebels. Normally a baboon trip splits up In small groups and goes off early in the day to find food. But one of the adolescent non-conformists of the Pump House Gang insisted on wandering by himself. His roaming took him to the military garbage dump. The baboon grasped a principle that chimps don’t seem to get. One man’s garbage is another primate’s gold. One man’s slush is another animal’s snow cone.

The baboon rebel found a way through the military garbage heap’s barbed wire fence, set foot in the trash heap, and tasted the throwaways. Pay dirt. He’d hit a concentrated source of nutrition. When they came back to their home base at the end of the day, the natural-living baboons, the ones who had stuck to their traditional food-gathering strategies, to their daily grind digging up tubers, came home dusty and bedraggled, worn out by their work. But the adolescent who invented garbage raiding came back energetic, rested, strong, and glorious. As the weeks and months went by, he seemed to grow in health and vigor. Other young adolescent males became curious. Some followed the non-conformist on his daily stroll into the unknown. And, lo, they too discovered the garbage dump and found it good.

Eventually, the males who made the garbage dump their new food source began to sleep in their own group, separated from the conservative old timers. As they grew in physical strength and robustness, these Young Turks challenged the old males to fights. The youngsters’ food was superior and so was their physical power. They had a tendency to win their battles. Females attracted by this power wandered outside the ancestral troop and spent increasing amounts of time with the rebel males—who continued to increase their supply of high-quality food by inventing ways to open the door latches of the houses of the officers’ wives and taught themselves how to open kitchen cupboards and pantries and who also Invented ways to make their way through the electrified fences of farmers and gather armloads of corn. The health of the males and females in the garbage-picking group was so much better than that of the old troop that a female impregnated in the gang of garbage-pickers and farm-raiders was able to have a new infant every eighteen months. The females in the old, conservative, natural-diet group were stuck with a new infant only every 24 months. The innovators were not only humiliating the conservatives in pitch battles, they were outbreeding them.

I find the above anecdote very appealing. It seems we got to learn a lot from the social species and baboons may just be the ones we should look at more closely.

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