Africa since the Mesozoic: with particular reference to certain biological problems.

Abstract

SUMMARY. The existing information about the Tertiary geology and elimate of Africa is collated and discussed critically. There is no evidence for a revolution in the climate and fauna of Africa (following incursion from Asia) after the Miocene. The arguments in favour of the equator having remained in its present position through the Tertiary are regarded as stronger than those in favour of its southward shift (through some 45). The passerine avifauna of Africa is analysed by biomes and with respect to its affinity with the avifaunas of Europe and Asia. The difference between the lowland evergreen and the savanna avifaunas is great, at the generic as well as at the specific level; that between the lowland evergreen and the montane evergreen is nearly as great–so much that they must largely have evolved in isolation from each other. Floristic evidence is adduced and compared with the faunistic. The bio‐geographical data are discussed in relation to the geological and the climatic.