The transition from matriarchy to patriarchy was probably a gradual one. First, the goddess was assigned an assistant, a lover-son or a husband-servant, who would occupy a secondary role in the story of procreation.
But later, the male gained a more aggressive role, sometimes symbolized by the bull. In fact, the figure of the bull is central to many mythologies. There are the sacred bulls of the Etruscans, the Hittite bulls of night and day, the Egyptian Min and Apis....