by the 1960s, there were only a few families still living as nomads in the desert. most of them had heard about white people and places like papunya. but they had not come into contact with them. they chose to keep living in the way they had always lived. this was a problem, because they were all closely related. pintupi follow a strict system of kinship (called skin groupings) that says who they can marry. it makes sure they avoid inbreeding. as not many families were left in the big desert, there were almost no eligible partners for the younger men and women.