Can you study a tribe without contacting it?

What if to save something spectacular you had to risk both its total demise and your own life?

That was journalist Scott Wallace’s predicament when he traveled to Brazil in 2002 to chronicle an unprecedented expedition deep into the Amazon rainforest. In his new book, The Unconquered, Wallace recounts the treacherous quest of a 34-member team of frontiersmen and activists hoping to protect Brazil’s indigenous Flecheiros, or “arrow people”—and the valuable, resource-rich land they inhabit—from commercial interests. To protect the arrow people, the well-meaning outsiders had a daunting task: They had to get close enough to evaluate the tribe’s safety without actually making physical contact, which could have spread devastating disease to the natives.

Wallace described his harrowing experience to a packed crowd at the National Geographic Society in Washington, D.C., last Thursday.

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