Effective population size and persistence of Anopheles arabiensis during the dry season in West Africa

Abstract. The way that the malaria vectors Anopheles arabiensis and An.gambiae survive the dry season in sub-saharan Sahel or northern Savanna areas of Africa remains enigmatic. We examined this problem by calculating the effective sizes (N_e) of An.arabiensis populations for several locations in West Africa. An indirect/genetic procedure was used, comparing gene frequencies at several time intervals. The amount of drift which occurred provides an estimate of N_e. Most estimates of N_e were approximately 2000 individuals, probably close to the yearly minimum. This supports the hypothesis that populations of An.arabiensis in this region are continuous throughout the year, with many individuals surviving through the dry season, perhaps in a physiologically altered state, rather than extinction or severe bottlenecks during the dry season, followed by recolonization by a few individual survivors or immigrants in the subsequent rainy season.     

A turning point? The Arab Spring and the Amazigh movement

This study examines the place of the Amazigh movement and communities in the evolving political fortunes of North African states. It evaluates the prospects for attaining a genuine recognition of Amazigh ethnocultural demands as part of a broader democratic transformation of society and state, and the Amazigh movement's likely contribution to that transformation. The Amazigh movement has the potential to make alliance with governments and other sectors of societies, in part to try and balance the strength of Islamist groups. However, the process is only at the beginning stages, and there is also a possibility that Amazigh self-assertion may lead to greater polarization of North African societies.