Possuelo, 58, leads Brazil's Department of Isolated Indians. He is an expert on the native tribes of the Amazon, so he knows an important Korubo belief: only enemies arrive in silence. Weeks after the singing introduction, Possuelo and his crew slowly made friends with the Ko-rubo. The Indians traded handmade bracelets for Possuelo's hats, knives and pots. Even better, Possuelo persuaded Brazil's government to protect the tribe's land. Possuelo's job is dangerous, but he loves it. He is helping preserve not only the natives' way of life but also their rain-forest habitat, the world's richest spot for plant and animal species.

At Home in the Jungle
Dozens of tribes make their home among the bright parrots and leafy guava trees in unexplored pockets of the Amazon. They hunt for food and make their own simple tools, clothing and shelter. But this life is endangered by gold miners, farmers and others pressing into new areas of the rain forest. In the past, the Brazilian government responded by trying to prepare the tribes to live in modern society outside the forest.

Possuelo thought that the Indians and the rain forest deserved a better solution. As a boy, he was fascinated by stories of two adventurous brothers who protected endangered tribes, and he knew that he wanted to spend his life continuing their work.

Over time, Possuelo convinced the government that instead of trying to modernize isolated tribes, it should shield Indian land and traditions from the modern world. That way, says Possuelo, the Indians "can live their traditional life-style."

Tracking Down a Tribe
Today seven teams work full time to find isolated tribes. Because many Indians are angry with outsiders for ruining the rain forest, contacting them is a slow, dangerous process. Says Possuelo: "It involves months at a time of being in the jungle."

Often Brazil's National Indian Foundation hears about new tribes through other tribes or as a result of confrontations with settlers. Last April, for example, Possuelo discovered Brazil's latest isolated group after three farmers were killed by arrows near the border of Peru.

Once Possuelo learns of tribes under threat, he assembles a team of explorers and natives who will help translate for him. They spend months studying the area before heading in by boat and on foot. Possuelo usually brings gifts. Sometimes the tribes react violently. Possuelo is a pro at solving disputes and rescuing fellow outsiders, yet he has been ambushed by one tribe and beaten by ranchers: "I have been in many dangerous situations."

After he has spent several weeks with a tribe, Possuelo leaves and sends back government guards to keep out loggers, ranchers and miners. Since finding the tribe last April, Possuelo has asked local authorities to remove farmers from the tribe's land and station more officials there.

The Indians are thankful they can again roam free through their lands. Environmentalists praise Possuelo for the protection he provides for the rich rain forest and all its species, human and nonhuman. He has even helped scientists find medicines among the Amazon's unusual plants. But Possuelo insists that he is not a hero: "I like the jungle and Indians. It is not a sacrifice for me."