The Custodians of Life : THE ELDER BROTHERS: A Lost South American People and Their Message About the Fate of the Earth <i> By Alan Ereira</i> , <i> (Alfred A. Knopf: $23; 243 pp.) </i>

One opens a book about “lost” Indians bearing ancient truths with a wearisome sense of deja vu. To the European invaders of the “New World,” the Indian has so often been a symbol--of wisdom or ignorance, freedom or servitude, brutality or gentleness, you name it--so seldom a human being. In unskilled hands, the current vogue for the Indian as nature’s ecologist becomes merely a new guise for the Noble Savage, a patronizing myth.

Fortunately Alan Ereira, a British historian and filmmaker, is aware of this semiotic baggage, and while he does indeed bring us an environmental warning, it comes not from a white image of what Indians should be but from the Indians themselves. “The Elder Brothers” is a wonderful book: a witty travel memoir about a remote corner of Colombia, a crisp introduction to a fascinating people, and the record of a paradoxical encounter between two incompatible worlds. One of these worlds is familiar to us--the world of documentary television (Ereira wrote this while making an ethnographic film for the BBC). The other belongs to the Kogi, “a nation whose fields have been continuously cultivated and towns continuously occupied for more than a thousand years.”

The Kogi live in the Sierra Nevada de Santa Marta, a great pyramid of mountains in the northeast corner of Colombia, rising from the Caribbean shore to heights of 19,000 feet. This range (separate from the Andean chain) is a wooded, indigenous outcrop, aloof from the surrounding lowlands deforested by Spanish sugar plantations, the United Fruit Co. and now by land-hungry Colombian peasants.

It looks down on the city of Santa Marta, where the Spaniards established a fort in 1525, and on tatterdemalion towns like Aracataca, immortalized as “Macondo” by its most famous son, novelist Gabriel Garcia Marquez. Today the country below the quiet Kogi world is rife with bandits, oil-drillers, tomb-robbers, guerrillas and cocaine warlords, all of whom, as Ereira puts it, “value their privacy” and may view the arrival of a stranger “as a useful opportunity to see if a gun is working properly.”

Before Columbus this was the home of the Tairona civilization, whose web of stone roads and cities can still be traced throughout the region. Like the Incas of Peru and the Maya of Central America, the Tairona fought a losing battle to defend their home until the 17th Century. Reduced to a tiny fraction of their former strength by Old World disease and Spanish attack, the survivors retreated higher and higher into the Sierra, where they were able to force a stalemate between the invaders and themselves. The Kogi and two related groups (about 20,000 people all told) are the Tairona’s descendants. Some of them live on the great stone terraces of their ancestors, and their priests, known as mamas, still recite prayers and epics in the Tairona language, an archaic form of modern Kogi.

Ereira did his homework, reading sources from colonial times to the present, visiting anthropologists and local experts. He learned that the Kogi, like many Native Americans, believe they are custodians, not masters of life; they remember their history in detail, and they call the intruders from across the sea their “Younger Brothers,” a polite term considering how we have treated them.

The Kogi wanted only one thing from us: to be left alone. Self-invited visitors to their thatched towns normally received, Ereira writes, “the traditional Kogi greeting: ‘When are you leaving?’ The Kogi . . . know what the Younger Brother is doing at the base of the mountain, and they regard him with deep mistrust. . . . We are thieves, murderers, the destroyers of people, of culture, of the world. . . . They have learned that hospitality is the most dangerous virtue on earth.” A previous filmmaker, British, “was beaten, and violently ejected.”

Through lucky timing, and the sensitive nature of his approach, Alan Ereira succeeded where others failed. He won the Kogi’s permission to work among them--something he claims they have never allowed before and will not allow again. He believes that they agreed to this only because they wish to say something of great importance to their Younger Brother, whose behavior has become so intolerable that he can no longer be ignored: They want to tell us that we are killing the world. Unless we stop our pillaging of minerals, fuels, forests and sacred sites, the Mother of All Life will die.

Throughout the book, Ereira explores the sources of this message and the reasons the normally reclusive Kogi are so anxious to deliver it, often quoting from speeches made by the priests in their meeting halls. The message is essentially the same one that Native Americans have been trying to get across to European man for centuries; it is the message of Black Elk (1930s), of Sitting Bull (1880s), of the Inca writer Felipe Waman Puma (ca. 1600), and of the Maya prophet Chilam Balam (ca. 1550). In the poetic words of the Kogi:

“We know how to bless the world and make it flourish. . . . The Younger Brother, all he thinks about is plunder. The Mother looks after him too, but . . . he is cutting into her flesh. He is cutting into her arms. He is cutting off her breasts. He takes out her heart. He is killing the heart of the world.”

The Kogi are as ethnocentric as ourselves: We think they are primitive; they think we are mad. Where we believe we have a right to “develop” the world, they believe it is their job to care for it with rites that maintain physical and metaphysical balance.

This belief is founded in a subtle and complex religion that can stand beside the great faiths of the East. Their concept of aluna (the spiritual essence of the universe) resembles the Tao, and the Kogi duality structure recalls yin and yang.

But we should not suppose that these ideas are derived from the Old World; they are found in various forms throughout native America from very early times. In short, the Kogi preserve the ancient wisdom of this hemisphere, though Ereira gets a bit carried away when he claims that they “represent the most complete surviving civilization of pre-Columbian America.” This is his first work with Amerindians, so he may be forgiven for not knowing that the millions who still speak Maya, Inca and other native languages have retained their ancestral knowledge to the same degree.

All these peoples are not mere relics; they are living cultures, still nurturing and building on their heritage. The Kogi, as Ereira says, are far from ignorant about the modern world. They have heard of atomic bombs, acid rain, and other milestones of progress--news that only deepens their anxiety. The Kogi have been hiding, but they are not lost.

At the end of the book, Ereira takes a helicopter ride to the sacred mountaintops, a crass but necessary intrusion--for what he sees there confirms why the Indians have chosen to break their long silence. While their view of the world is very different from ours, their warning to us has been spurred by precise empirical observation:

The Sierra Nevada is in effect a microcosm of the planet, spanning a full range of climate zones from steamy rain forest to eternal snows. Its glaciers are a vast storehouse of water, the amniotic fluid of life. Kogi priests have been visiting these ice fields regularly for hundreds, perhaps thousands, of years; over the last few decades they have seen more and more evidence of catastrophic change. Glaciers have receded, mountain lakes have shrunk, plants have died out.

Are these changes natural or artificial? Are they temporary or irreversible? Our scientists still debate the reality of global warming; the Kogi are certain it is happening. And they do not need doctorates to know why: It is caused by their Younger Brother cutting down trees, burning fossil fuels, scattering toxins.

“Younger Brother, stop doing it. You have already taken so much. We need water to live. Without water we die. . . .”

The Kogi know this, even if we still try to ignore it, and they chose Alan Ereira to tell us. They made a good choice.