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Current knowledge of the vegetation response to climate changes in tropical Africa and particularly the reconstitution of stand dynamics is severely limited by the scarcity of long and complete, well-dated, pollen sequences. Additional difficulties come from the specific characteristics of pollen analysis in tropical ecosystems linked to the large number of tree species (an order of magnitude more than in temperate regions), their low pollen productivity, and the small number of grains that are currently determined at a specific level. This leads to extreme underrepresentation or the absence of many tree species in pollen diagrams. However, due to developments in database management, more than 580 fossil pollen sites have been identified in Africa and surrounding areas, among which 350 are available in the form of raw data. These show that the shift from dry and cold to wet and warm conditions at the last glacial-interglacial transition led to the widespread increase in tree cover throughout the tropics: Tropical trees migrated north and penetrated into the Saharan desert during the Holocene, whereas forest communities expanded upwards in the eastern African highlands and included plant species that are currently present at low to mid altitudes. This demonstrates that climate changes have not only caused migrations of plant communities but also profoundly influenced relations between species. During the Holocene, the environmental response to short climate events is strongly dependent on local hydrological conditions, as illustrated by the record of vegetation changes in the Equatorial lowlands to the dry climate event recorded approximately 4,000 160;cal 160;yr 160;BP.