A Dassanech man shows off his distinctive painted clay hairdo. The central panel consists of tightly packed coils of sisal thread extracted from grain sacks that allow the scalp to breathe underneath the clay. The scarification on his chest indicates that he has killed a man in combat. Much the largest of the tribes in the Omo Valley numbering around 50,000, the Dassanech (also known as the Galeb, Changila or Merille) are Nilotic pastoralists and agriculturalists.