The native man of Papua New Guinea is wearing only this thing, called Koteka, and nothing else.

This penis sheath is made from the outer rinds of a pumpkin like fruit.

The men from New Guinea shown in the pictures would feel undressed in public if they did not have the narrow gourd sheath over their penis tied in an erect position. 

Throughout most of the rest of the world, this would be viewed as a highly inappropriate style of dress to say the least.  Some clothing is worn to provide supernatural protection.

Depending on ethnic affiliation, the koteka may differ in shape, volume and length, but it is always worn in "present arms" position.

Most of these people are from tribe called Dani, Baliem Valley - island of New Guinea.

This man is sitting next to the few hundred years old mummy of former tribe chief.