Parallel cousin

Parallel cousin is an term denoting   who are in the same  as the subject and are from the parent's same-sexed sibling. A cross cousin is from the parent's opposite-sexed sibling. Simply put, a parallel cousin is a who is the child of the father's brother (paternal uncle's child) or the mother's sister (maternal aunt's child), while a cross cousin is the child of the mother's brother (maternal uncle's child) or of the father's sister (paternal aunt's child).



The role of cross cousins is especially important in some cultures (such as the and among ) where  between them and the subject (ego). Parallel cousins, on the other hand, are usually not the subject of since a union in many cultures would fall under an. In a, parallel cousins are part of the subject's (ego's) whereas cross cousins are not. The same is true in societies, wherein parallel cousins are considered to be related to the subject (and therefore unwedable) while cross cousins are not.

Naming conventions
In many societies parallel cousins use names that we often associate only with direct siblings. For instance, in the, a male parallel cousin is referred to as "brother". Likewise, a female parallel cousin is "sister." This system is also in place in the, the , and. The is different in that they apply sibling naming terminology to cross cousins as well. This system is not in use in the, nor in the as they have separate terminology for cross and parallel cousins.

Family taboos and kinship
, in "The Evolution of Sex" notes that suggested the following reason for the intermarriage  on parallel, but not on s. Fathers who are also brothers may overtly or covertly share sexual access to the wife of one or the other, raising the possibility that apparent parallel-cousins are actually half-siblings, borne by the same mother. Likewise, mothers who are also sisters may overtly or covertly share sexual relations with a single man, raising the possibility that apparent parallel cousins are actually half-siblings, sired by the same father.

This possibility does not exist for cross-cousins, because in the absence of full-sibling incest, it is impossible for cross-cousins to share a mother or a father by overt or covert sexual relationships. Neither Ego's father's sister, nor his mother's brother can possibly be his parent, unless full-sibling incest has occurred. It is possible, however, that Ego's father may father a child with Ego's Mother's Brother's Wife, thereby allowing cross-cousins to be covert half-siblings, sharing the same father.

Sources and external links

 * Kin Naming Systems (part 1) at Palomar College
 * Kin Naming Systems (part 2) at Palomar College
 * Maynard-Smith, J. (1978) "The Evolution of Sex" (Cambridge University Press).
 * Matrilineal and Patrilineal Kin at the University of Manitoba
 * Cross-Cousin Marriage at the University of Manitoba