Behavioral and environmental determinants of reproductive success in traditional Moroccan Berber groups.

The reproductive histories of women aged 45-70 years from a homogeneous Berber population of South Morocco were sampled from three contrasting environments: a small town (n = 75), villages in the lowlands (n = 217), and villages in the highlands (n = 128). The main reproductive variables oppose the relatively better conditions of fertile life in the lowlands to the more hostile ones in the highlands. Path analysis confirms this difference through reproductive behaviors and suggests the existence of mechanisms for controlling family size in town and in the rural lowlands, but not in the highlands. The estimates of survival function show significant differences among the three groups, the conditions for survival in the highlands being clearly less favorable. Rank tests of the association of survival data with several covariates indicate the association of survival data with vaccinations and with conditions of delivery. In spite of the lower rate of offspring survival, the highlander group would demonstrate a higher overall number of children reaching reproductive maturity, thanks to an extended reproductive span.