Nature 274, 356 - 358 (27 July 1978); doi:10.1038/274356a0

Neolithic hyperarid period preceded the present climate of the Central Sahel

HENRI J. DUMONT

Instituut voor Dierkunde, Rijksuniversiteit Gent, Belgium

THE chronology of Pleistocene climatic changes in the Sahara is well known, but that of the Sahel is little understood. Yet, in the Sahel, between the Ferlo Desert (Senegal) and the centre of the Republic of Sudan, there is a nearly continuous belt of fossil dunes. Although their age is unknown¹, they reflect Pleistocene expansions of the Sahara, and thus alternations of wet and dry climates. I have analysed the relict aquatic fauna of the Sahara−Sahel belt, and report here evidence that the present climate of the Central Sahel between the Middle Niger river and the Chad depression was preceded by a hyperarid period.

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