The first thing is that there are two moieties, Dhuwa and Yirritja. Everyone and everything is either Dhuwa or Yirritja. Yirritja people sing about Yirritja things, like Yirritja rocks, Yirritja winds, wildlife, clouds, ancestors, creators, and many things.
A Yirritja person must always marry a Dhuwa person, and Dhuwa must marry Yirritja. You can’t marry the same moiety. That’s how the world works. It has been there for thousands of years. We live by that.
If a man or a woman is Dhuwa, their mother will be Yirritja. Also, Dhuwa land can have another piece of land nearby which is its mother, Yirritja. For example, the Gumatj land at Bawaka (pictured above), which is Yirritja, is right next to its mother, the Rirratjiŋu homeland centre named Yalaŋbara, which is Dhuwa.
Everywhere we can find the child and the mother, not only when we see people, but also when we see the land. This relationship is commonly referred to as Yothu-Yindi. In a Yothu-Yindi partnership, one partner is always Dhuwa, the other always Yirritja. The Yindi is always considered to be the mother of the Yothu, even if we are talking about two men, or two pieces of land. Sometimes Yirritja is the mother for Dhuwa, sometimes Dhuwa is the mother for Yirritja.
Notes from a talk by the late Dr. Raymaṯtja Marika-Munuŋguritj, lecturer
Faculty of Aboriginal and Torres Strait Islander Studies (FATSIS)
Charles Darwin University & Yolŋu Advisor to FATSIS
The Dhuwa and Yirritja are almost like two separate cultures that coexist and interact in the Yolŋu world. Each has its own sets of mythologies, parts of which are owned by different clans that belong to that particular moiety. Nothing in the Yolŋu universe is excluded from this system or from these stories.