
As we walked through the dense jungle, the stillness was broken only by the zing of the Trailblazers' machetes ahead of us and the occasional chatter of monkeys, swinging like trapeze artists through the treetops. It was 2002 and I was an only partway through a three-month expedition into the depths of the Javari Valley Indigenous Land in far-western Brazil, a sprawling reserve that harbours the largest concentration of uncontacted and isolated tribes in the world.