The Awá year is divided into "sun" and "rain"; the rains are controlled by celestial beings called mai ra who oversee vast reservoirs in the sky. When the moon is full, the men, their dark hair speckled white with king vulture feathers, commune with the spirits through a chant-induced trance, during a sacred ritual that lasts until dawn.

For centuries, their way of life has been one of peaceful symbiosis with the rainforest. But over the course of four decades, they have witnessed the destruction of their homeland -- more than 30 percent of one of their territories has now been razed to make way for cattle ranches -- and the murder of their people at the hands of karaí, or non-Indians. Today they are one of the last nomadic tribes in Brazil. As they are so few in number (there are fewer than 100 uncontacted Awá, some of whom live outside any protected area), they are surrounded on all sides by hostile frontier forces such as ranchers, loggers and settlers who invade and kill with impunity; as a result, much of their forest has been destroyed. They are now also the most threatened tribe on Earth.

Karapiru's harrowing story really begins with a chance discovery in 1967 when American geologists were carrying out an aerial survey of the region's mineral resources. When the helicopter needed to refuel, the pilot decided to land on a treeless summit high in the Carajás Mountains. One geologist reputedly noticed a scattering of black-grey rocks on the ground. In fact, the soil beneath him contained what a geological magazine would later refer to as, "a thick layer of Jaspilites and lenses of hard hematite." In layman's terms, the prospectors had just touched down on the planet's richest iron ore deposit.