Frequently, membership to the group of descent is determined at birth and lasts a lifetime. In this case, it is an assigned status.
Ancestry groups Ancestry groups are usually exogy (Members should look for their partners in other ancestry groups). Two common rules serve to admit certain people as members of the group of descent and others
to exclude them. With a rule of matrilineal descent, people join the mother’s group automatically at birth and remain members throughout his life. With the Patrilineal Ancestry, people automatically have a livelihood membership in the father’s group. (In Figures 10.4 and 10.5, which show groups of matrilineal and patrilineal descent, respectively, the triangles represent males and circles, women.) The matrilineal and patrilineal ascendance are types of unilineal descent. This means that the rule of ancestry contemplates only one line, or the male or the feminine. Ancestry groups can be lineages or clans. Common with both is the belief that members descend from the same apical ancestor. This person represents the apex, or tip, of the common genealogy. For example, Adam and Eve, according to the Bible, are the apical ancestors of all humanity. Since it is said that EVA came from Adam’s rib, Adam represents the original apical ancestor for the Patrilineal Genealogies presented in the Bible. How do lineages and clans differ? A lineage uses demonstrated descent. Members can remember the names of their ancestors in each generation, from the apical ancestor to the present. (This does not mean that its count is accurate, the important thing is to who is considered members of the lineage.) In the Bible, the Langany of men who “began” other men is a demonstration of a wider pathway, That at the end of accounts includes Jews and Arabs (those who share Abraham as their last common apical ancestor). Unlike lineages, clans use stipulated ancestry. The clan members simply say they descend from the apical ancestor. They do not try to trace the real genealogical links between them and that ancestor. The Betsilee of Madagascar possess both clans and lineages. Ancestry can be demonstrated in the last 8 or 10 generations, then sometimes trace a vague link in the most remote past, as it would be with sirens or foreign royalty, which at some point may have been mentioned by its founders (Kottak, 1980 ).