The corpus of historical data from lake sediments relating to the climate, vegetation, and human land use of the lowland Central American tropical forest between ca. 20,000 BP and the time of European contact is reviewed. Pollen, phytolith, and charcoal records identify the distribution and composition of tropical vegetation and fire patterns during the late Pleistocene, when they were significantly altered from today's, and earliest Holocene, when plant communities reassembled and interglacial representatives began to coalesce on the landscape. The significance of the environmental perturbations that occurred during the transition from the Pleistocene to the Holocene for human occupation of the lowland tropical forest and the geography and chronology of agricultural origins is discussed. Fire was employed by hunters and gatherers and farmers alike during the past 11,000 years as a primary tool of forest modification. The profound effects of an ancient pre-Columbian development of plant food production and, subsequently, slash and burn agriculture between ca. 10,000 BP and 4000 BP can be seen on lowland forests from Mexico to the Amazon Basin.