Members of the Xingu Indian tribe dance during a ritual in t

BRAZIL - MARCH 28: Members of the Xingu Indian tribe dance during a ritual in the Amazon forest of Brazil, on March 28, 2006. Lawmakers are debating a bill to allow companies such as Cia. Vale do Rio Doce and Anglo American Plc to team up with Brazil's 400,000 Indians, most of whom have little contact with western civilizations, to tap unexplored land. While supporters say it will curb violence and environmental damage caused by illegal digs, many indigenous groups say it threatens their way of life. (Photo by Adriano Machado/Bloomberg via Getty Images)