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Firmly based palaeoenvironmental data for southern Africa prior to 40,000 yr B.P. are sparse. The only site which is likely to be able to provide useful information for Isotope Stage 6 is the Pretoria Saltpan; warming at the end of this stage appears to have been rapid and to have been associated with increased precipitation in the interior of the sub-continent. In contrast, dry conditions appear to have prevailed in the southwestern areas during the warmest phases of Isotope Stage 5. This regional difference first became apparent during the Pliocene. During the Last Glacial Maximum temperatures based on isotope ratios reached their lowest values of 5-6°C below present, in the southern part of the subcontinent, and widespread dryness prevailed. Warming became quite rapid after 16,000 yr B.P. and was almost everywhere associated with a marked increase in wetness to around (or even above) present levels. This warming phase continued until the beginning of the Holocene; the terminal Pleistocene was, however, marked by desiccation in the arid western areas. Of special interest is the Holocene altithermal, which can be placed between 7000 and 6500 yr B.P. The extent of the temperature rise cannot be specified with any precision, but probably did not exceed the Holocene mean by more than 2°C. In the southern Cape and Karoo more summer rain apparently occurred than during Isotope Stage 2 and in the early Holocene, and this trend towards year-round rainfall appears to have become increasingly pronounced through the later Holocene until about 2000 yr B.P. This argues, in a general way, for an increase in the proportion of summer rainfall with rising temperature in the present winter rainfall areas of southern Africa.