The integration of contemporary ecological data is increasingly recognized as an essential component to reconstructions of early hominin dietary behavior. Paleoanthropologists recognize the significance of plant foods in early hominin diet, and the need to understand habitat selection when reconstructing the feeding ecology of extinct species.
Dental microwear and stable carbon isotope analyses have enhanced our understanding of early hominin dietary behavior and called previous assumptions into question. The pronounced craniodental robusticity of Paranthropus was originally interpreted as an adaptation to a hard-object diet. However, dental microwear and isotopic studies reveal that East African Paranthropus boisei focused its diet on tough C4 plant foods, such as grasses/sedges.
Hence, we face the possibility that Paranthropus morphology allowed for some degree of dietary flexibility, and that food choice was dictated as much by the nutritional properties and spatiotemporal availability of wild plant foods as by masticatory adaptations. Therefore, an understanding of how wild plant foods in modern African savannas vary across habitat and season may explain the dietary differences we see between early hominin species living in eastern and southern Africa. Currently, empirical data on the nutritional properties of wild plant foods from modern African savanna habitats are relatively scant.
Results/Conclusions
We present protein/fiber ratios (crude protein/acid detergent fiber) of wild plants growing in savanna habitats from SANParks Kruger National Park, South Africa. Protein/fiber ratios are often regarded as good indicators of forage palatability for a wide range of herbivores. Additionally, we compare our results to data collected by our team in East Africa, and the South African Highveld.
We find that significant variation exists within habitats and plant categories, and that C4 grasses are more variable than is often assumed. This variability has been under-explored in hominin dietary reconstructions.
This variation among grasses (the dominant C4 biomass on these landscapes) may have implications for the different carbon isotope ratios observed between eastern and southern African Paranthropus.
Project funded by: European Research Council, EU Horizon 2020, grant number STG-677576 (”HARVEST”). This is a research project, in whole or in part, of the Nutritional and Isotopic Ecology Lab NIEL lab at CU Boulder.