1Anthropology, University of California, Santa Cruz, 2Fort Lauderdale Research & Education Center, University of Florida, 3School of Biological and Environmental Sciences, Liverpool John Moores University, 4Department of Primatology, Max Planck Institute for Evolutionary Anthropology, 5Department of Anthropology, University College London
April 17, 2020 , Platinum Ballroom
It has been proposed that the consumption of C4 plant feeding termites may have led to the relatively high carbon isotope signatures observed in many fossil hominins. Previous analysis of carbon stable isotopes in termites from Kruger National Park found that an average of 35% of termite diets were comprised of C4 plants. However, given the diversity of termite ecology across genera and localities, those results are unlikely to be representative of the isotope ecology of all termites that could have been exploited by hominins. In the present study, we analyzed the carbon and nitrogen stable isotope ratios of 79 termite samples within the genus Macrotermes located at six savanna woodland sites inhabited by chimpanzees and utilized stable isotope mixing models to determine the input of C4 plants within these samples. Additionally, we tested the effect of termite caste and habitat type in a subset of 47 samples from 12 mounds from the same field site. Our results suggest that C4 plants comprised only 5-15% of Macrotermes diets across all six sites. Caste and habitat type had significant effects on carbon, but not nitrogen, isotope values in the subset we analyzed. The major soldier caste of Macrotermes subhyalinus had the most depleted carbon isotope signatures. These results call into question prior hypotheses of termite consumption by early African hominins as well as recent work on chimpanzee isotope ecology.
This project was funded by the Max Planck Society and the Krekeler Foundation as well as the University of California, Santa Cruz.