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The relationship between ungulate stable carbon isotope values and environmental variables (temperature, relative humidity, precipitation) remains poorly understood. In this paper, we evaluate this relationship for, predominantly, C-3 ecosystems in the winter rainfall areas of southern Africa. In our dataset (290 individuals representing 23 species), delta C-13 values of ungulate enamel are significantly correlated with mean annual precipitation (MAP), moisture index (MI) and summer aridity index (SAI), variables that also influence the distribution of C-3/C-4 grasses. Our study confirms previous findings that faunal delta C-13 values in C-3 ecosystems are most strongly correlated with variables related to precipitation. delta C-13(enamel) values for ungulate browsers are more strongly correlated with a larger number of environmental variables than values for grazers and mixed feeders and vary according to vegetation type. We apply regressions derived from the modern dataset to estimate palaeoclimatic shifts based on delta C-13(enamel) values of browsing fauna at the Pleistocene sites of Hoedjiespunt and Elandsfontein in South Africa.