This chapter describes a simulation program for the study of human populations, comparing and contrasting its various facets with other programs that have similar objectives. It presents some of the results of the simulations, together with a theoretical discussion of their importance. The model for simulating small human populations has been implemented. The chapter discusses the effect of marriage systems on drift. Different marriage systems imply different levels of consanguineous marriage, and it might be expected to have an effect on drift. Evidence of significant differences has not been found in rates of drift. This might be because of the degeneration and breakdown of some systems, and to the relatively low preference for marrying according to the prescribed rules. The preliminary results from further simulations incorporating lower probabilities of violating the system have shown small differences in genetic drift. The investigation of the effect of degeneracy of the marriage systems on drift is difficult. Increasing population size and decreasing the probability of violating the marriage system reduces the probability of systems degenerating, and such simulations showed small differences in rates of drift.
