What is "ambilineality"

Ambilineality is a system containing both unilineal descent groups – i.e. both patrilineal and matrilineal groups – in which one belongs to one's father's and/or mother's descent group ( lineage). In traditional ambilineal cultures such as those listed below, the individual has the option of choosing their own lineage.

Societies practicing ambilineal descent are especially common in Southeast Asia and the Pacific. Polynesian cultures are generally ambilineal, including, for example, Samoans, Māori and Hawaiians. The indigenous peoples of Northwestern North America are also practitioners of ambilineality; and it also often occurs among the Yoruba people residing in West Africa, particularly those of royal and/or noble descent.