A clan is a group of people united by kinship and descent, which is defined by perceived descent from a common ancestor. Even if actual lineage patterns are unknown, clan members nonetheless recognize a founding member or apical ancestor. As kinship based bonds can be merely symbolical in nature some clans share a "stipulated" common ancestor, which is a symbol of the clan's unity. When this ancestor is not human, this is referred to as animallian totem. Generally speaking, kinship differs from biological relation, as it also involves adoption, marriage, and fictive genealogical ties. Clans can be most easily described as sub-groups of tribes and usually constitute groups of 7000 to 10 000 people. Some clans are patrilineal, meaning its members are related through the male line; for example, the clans of Armenia. Others are matrilineal; its members are related through the female line. Still other clans are bilateral, consisting of all the descendants of the apical ancestor through both the male and female lines; the clans of Scotland are one example. Whether a clan is patrilineal, matrilineal, or bilateral depends on the kinship rules and norms of their society. In different cultures and situations a clan may mean the same thing as other kin-based groups such as tribes and bands. Often, the distinguishing factor is that a clan is a smaller part of a larger society such as a tribe, a chiefdom, or a state. Examples include Irish, Scottish, Chinese, and Japanese clans, which exist as kin groups within their respective nations. Note, however, that tribes and bands can also be components of larger societies. Arab tribes are small groups within Arab society, and Ojibwa bands are smaller parts of the Ojibwa tribe. Apart from these different traditions of kinship, further conceptual confusion arises from colloquial usages of the term. In post-Soviet countries for example it is quite common to speak of clans referring to informal networks within the economic and political sphere. This usage reflects the assumption that their members act towards each other in a particularly close and mutually supportive way approximating the solidarity among kinsmen. However, the Norse clans, the ätter, can not be translated with tribe or band, and consequently they are often translated with house or line.