The Dani people (also spelled Ndani) are a people from the Central Highlands of Western New Guinea in Baliem Valley, Highland Papua, Indonesia. They are sometimes conflated with the Lani group to the west. They are one of the most populous tribes in the highlands, and are found spread out through the highlands. The Dani are one of the best-known ethnic groups in Papua, due to the relatively numerous tourists who visit the Baliem Valley area where they predominate. "Ndani" is the name given to the Baliem Valley people by the Moni people, and while they call themselves "Hubula", they have been known as Dani since the 1926 Smithsonian Institution-Dutch Colonial Government expedition to New Guinea under Matthew Stirling who visited the Moni. Language Linguists identify at least four sub-groupings of Dani languages: Lower-Grand Valley Dani (20,000 speakers) Mid-Grand Valley Dani (50,000 speakers) Upper-Grand Valley Dani (20,000 speakers) and the Lani or Western Dani (180,000 speakers) The Dani languages differentiate only two basic colours, mili for cool/dark shades such as blue, green, and black, and mola for warm/light colours such as red, yellow, and white. This trait makes it an interesting field of research for language psychologists, e.g. Eleanor Rosch, eager to know whether there is a link between way of thought and language. First contact A small fringe group of the Dani, living south of Puncak Trikora and presenting themselves as the Pesegem and the Horip tribes, were met on 29 October 1909, by the Second South New Guinea Expedition led by Hendrikus Albertus Lorentz, who stayed several nights in their village. First contact with the populous Western Dani was made in October 1920 during the Central New Guinea Expedition, which group of explorers stayed for six months with them at their farms in the upper Swart River Valley (now Toli Valley). The Grand Valley was only sighted on 23 June 1938 from a PBY Catalina by Richard Archbold, who stumbled upon the valley while studying high altitude vegetations in Jayawijaya Mountains. The first white people to live among the Dani were John and Helen Dekker, under whose ministry the Christian population among the Dani grew to 13,000. Culture Sweet potatoes are important in their local culture, being the most important tool used in bartering, especially in dowries. Likewise pig feasts are extremely important to celebrate events communally; the success of a feast, and that of a village big