EcoWatch: As I traveled by boat down the Xingu River to visit indigenous villages that would have been flooded by the massive Belo Monte Dam, I came to understand why the local people thought of their land as the Center of the Earth. The massive rivers, seemingly eternal jungle and liquid blue-grey sky made me feel as if I was heading farther into the center of a lush, green ecosystem that was bigger and more encapsulating than the word ecosystem can describe. Though threatened by exploitation for its...