The broad band of the Milky Way that runs across the sky at night is commonly interpreted by Aboriginal groups as a legendary river. Several groups in the central desert believe the river divides two tribes of ancestor spirits who live on either side. To some groups, the stars along the river represent fish; other groups, such as the Yolngu, believe the stars are the campfires of their ancestors. Other groups identfy the Milky Way as the Rainbow Serpent, a major creator being.