Xingu Indians typically decorate their faces with various designs using the juice of the green fruit of the genipap tree (Genipa americana) which stains the skin black upon oxidation.  Similarly, they use natural dyes to color their hair.  In this photograph, they used the crushed seeds of annatto or urucum (Bixa orellana) to make a paste that was applied to the hair.  The design on the cheek represents the wings of a bird and indicates that the individual is a member of a bird clan.  The black genipap dye is semi-permanent, penetrating the skin and can not be washed off.  However, the dye fades after about two weeks.