Some lore for a nomadic culture

In environments where male aggression and absolute strength aren’t needed as much, because of a lack of mega fauna, nor inter tribal violence, there will be a lesser need for fully grown males to stick with the moving band. In this case, the men move about in groups of 3-5 fully matured men, and some of their nephews. Matriarchal groups will move with the grandma as leader, her daughters, and their children. If a man becomes elderly, he will court an elderly woman, typically the matriarch, and, in exchange for allowing him to live with her group and be fed by them, he will help watch over his adoptive grandchildren and serve as the matriarch’s personal stress relief.