Demographic consequences of incest tabus: a microsimulation analysis.

Theories of incest tabus usually stress the psychosocial advantages of marriage regulation. But marriage regulation may produce delays in mating and thus loss of fertility to a population. Computer microsimulation experiments measure the amount of fertility that must be achieved outside a normatively specified marriage system in order to keep population constant. This amount varies directly with scope of tabu and inversely with population size. For populations of hundreds it is negligible, but for populations of dozens it can be very great. In the latter, flexibility of marital arrangements may permit maintenance of fertility without repeated revision of rules of marriage.