Palaeoecological background: neotropics

Abstract

Strong changes of temperature and rainfall affected tropical South America during the last few millions of years; the sequence of the last glacial-interglacial cycle is relatively well known. The climatic changes had a profound effect on the vegetation, especially in the mountains, but data from the tropical lowlands are now increasing and show that the effect on lowland vegetation may also have been considerable. Very recent data from Eastern Brazil (Carajas) indicate that the rainfall in that area was lowered at least 500 mm during several dry phases of the Late Pleistocene, savanna vegetation replacing forest. If this lowering of rainfall was a regional phenomenon, the Amazonian forest may have been split up in at least two large areas separated by savanna and/or dry forest. -from Author