Bilateral descent

[2] While bilateral descent is increasingly the norm in Western culture, traditionally it is only found among relatively few groups in West Africa, India, Australia, Indonesia, Melanesia, Malaysia, the Philippines, and Polynesia.

Anthropologists believe that a tribal structure based on bilateral descent helps members live in extreme environments because it allows individuals to rely on two sets of families dispersed over a wide area.

[4] Genealogies featuring the legendary danish king Sigurd Snake-in-the-Eye gives him the matronymic name Áslaugsson due to his mother Aslaug's connection to Völsungs.

The Urapmin people, a small tribe in Papua New Guinea, have a system of kinship classes known as tanum miit.

Since they also practice strict endogamy, most Urapmin belong to all of the major classes, creating great fluidity and doing little to differentiate individuals.