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Micromammalian remains are relatively readily preserved in closed archaeological and palaeontological sites, as well as in modem barn-owl pellets, which act as controls. The animals themselves tend to have fairly precise habitat requirements and to respond quickly to environmental change. Long sequences of samples from the past can provide unique information on the nature and extent of climate change, as well as on conditions before human activities became a major agent of environmental change. So far, the evidence indicates that warm periods during the last 125 000 years in South Africa have not all been characterized by the same conditions. The evidence further indicates that during the last millennium the effects of natural climatic variability have only outweighed the depredations of humans in the presently more arid parts of South Africa. Several general conclusions arising from these facts could have a bearing on future planning. 1) Each investigation must be undertaken at the correct temporal and geographic scale; 2) Unsupported extrapolation from one event or region to another is unlikely to be reliable; 3) More southern grid points are needed in GCMs before accurate predictions can be made.