Wikipedia
In Yolngu mythology, the Djanggawul are three siblings, two female and one male, who created the landscape of Australia and covered it with flora. They came from the island of Baralku, and were eventually eaten by Galeru. The two female Djanggawul made the world's sacred talismans by breaking off pieces of their vulvas. They included Bunbulama, a rain goddess.
The Djanggawul myth specifically concerned the Dua moiety of people, including about a third of the clans that lived in northeast Arnhem Land. The humans born of the two sisters are the ancestors of the Dua clans, the animals the sisters created are the totem animals of those clans, and the places the sisters visited are the clan shrines.
The mythology was staged in early contact times by the Dhuwa ("Dua") during several days of dancing, singing, and the manipulation of sacred emblems, on a stage of man-made holes and earth sculpture. The other aboriginal moiety of the region, the Yirritja ("Yiritja"), also participated in the dramatization of the Djanggawul myth, although some of the rites were accessible only to initiated Dua males. Oliver, following Berndt 1952, argues that the Djanggawul cycle is a dramatic enactment of Arnhem Land's monsoon cycle, which shaped aboriginal food procurement activities. Oliver says, "This is not to say that a dramatic presentation was needed to familiarize the Arnhemlanders with the stark reality of their monsoon climate, and of its direct effects upon their lives; about that they were deeply aware. What the rituals did was to rationalize that climate in mythical terms (a reassuring thing in itself) and to provide them with a doubtless satisfying means of attempting to insure the regular recurrence of the rains. For no matter how discomforting the climate of the rainy season may have been ... the Arnhemlanders evidently recognized how essential it was for sustaining the only life they knew." (1989:169)