Wolunka is the culture heroine of the Wayuu origin cycle. In the most widely recorded version she is the daughter of the rain-god Juyá (some tellings also name Pulowi as her mother, while others say Maleiwa formed her), and at the dawn of time she was the only woman on earth. She was born with a toothed vagina and so could bear no children. While she bathed nude in a stream in the Makuira mountains, a pair of transforming twins lay in wait and loosed an arrow that struck her genitals and knocked out the teeth; her spilled blood stained the rocks that bear her name and, according to tradition, is the reason women menstruate and can thereafter conceive. The myth is understood as a cosmogonic account of the beginning of the Wayuu and is linked to the girls' seclusion rite observed at first menstruation.