One cool afternoon, a Cessna plane landed on a grassy field in the middle of the Papuan forests of Memberamo district. The attention of the passengers were drawn to hundreds of dark-skinned men, women and children, gathered around the airstrip. The men carried bows and arrows, their bodies smeared with dry mud and their heads, hands and feet twined with leaves. At first glance, they looked like warriors preparing for a battle. But the mens singi