The area dwelt by the Ngaanyatjarra people ("yarnangu") has a record of human habitation going back some 10,000 years. In traditional society, the Ngaanyatjarra comprised numerous bands, usually constituted by a group of a dozen people. Males only reached marriageable age at around 30, after a thorough training and graduation through a complex initiatory system, that transformed "tjilku" (male children) into "wati" (men). Passage to this status was marked by the right to wear a red headband, though as post-initiates ("tjawarratja") they were still required to dwell apart from the main camp as elders continued to instruct them. Learning the lore required that the initiates had to supply their elders with foodstuffs like meat, a scarce resource in the area. In this sense, the tjukurrpa system also functioned as a cross-generational mode of exacting obedience and an income from the younger men. Females entered into wedlock just after the onset of puberty. Ceremonial induction consisted of learning to absorb the complex details of tjukurrpa, namely the lore/law of the dreamtime. The process is graded so that full knowledge only comes after 50 the normal age after which one can begin gain recognition as a "wati yirna" or "tjilpi", a thoroughly knowledgeable elder, though even 60-year-olds can still be denied that recognition.