Using carbon isotope data of fossil bovid communities for palaeoenvironmental reconstruction

Reconstructing palaeoenvironments is a major focus of palaeoanthropological research. While many techniques are now available for exploring past environments, fossil bovids remain amongst the most widely utilized sources of environmental information. Most studies of fossil bovids, however, assume implicitly that bovid ecology is the same now as it was in the distant past. Because such uniformitarianist assumptions are not always valid, we have developed a method to provide palaeoenvironmental information from fossil bovids that requires no ecological assumptions. Here, we show that the percentages of C3 and C4 vegetation-consuming bovids in modern environments generally vary according to the amount of woody vegetation present. Application of this C3 / C4 index to the fossil bovid assemblage at Makapansgat shows that, based on carbon isotope data, the percentage of C3-consuming bovids is high, suggesting a great deal of woody vegetation in this vicinity about 3 million years ago