Many peoples around the world have origin stories regarding their common ancestors. It is now possible to determine whether these stories have a basis in reality, or whether they are simply common myths. A new study tries to answer this question for several ethnic groups from Uzbekistan. As the authors point out, these are very conservative, previously nomadic, patrilineal groups with elaborate genealogies going up to 60 generations. By studying their Y-chromosomes the authors examine whether or not they share an ancestor at the various kinship levels recognized by them: lineage, clan and tribe. It is shown that lineages do in fact have common ancestors, whereas tribal ancestors are largely mythological. Thus, tribes may be formed by the coming together of various clans who invent a mythological ancestor to justify their union.
Am. J. Hum. Genet., 75:000, 2004
The Genetic or Mythical Ancestry of Descent Groups: Lessons from the Y Chromosome
Raphaëlle Chaix et al.
Traditional societies are often organized into descent groups called "lineages," "clans," and "tribes." Each of these descent groups claims to have a common ancestor, and this ancestry distinguishes the group's members from the rest of the population. To test the hypothesis of common ancestry within these groups, we compared ethnological and genetic data from five Central Asian populations. We show that, although people from the same lineage and clan share generally a recent common ancestor, no such common ancestry is observed at the tribal level. Thus, a tribe might be a conglomerate of clans who subsequently invented a mythical ancestor to strengthen group unity.