Each Ovambo tribe had a hereditary chief who is responsible for the tribe. Many tribes adapted representation by having a council of headmen who run tribal affairs. Members of the royal family of the Owamboland are known as "aakwanekamba", "ovakwaluvala", "ovakwamalanga", "ovakwaanime", "aakwanyoka" and many more; only those who belong to this family by birth, through the maternal line, have a claim to chieftainship. The tribes figure their descent by a matrilineal kinship system, with hereditary chiefs arising from the daughter's children, not the son's. Polygyny is accepted, with the first wife recognized as the senior.