Research Laboratory for Archaeology, Oxford University, Oxford OX1 3QY, United Kingdom.
Proc Natl Acad Sci U S A. 2012 Dec 11;109(50):20369-72. doi: 10.1073/pnas.1204209109. Epub 2012 Nov 12.
Foods derived from C(4) plants were important in the dietary ecology of early Pleistocene hominins in southern and eastern Africa, but the origins and geographic variability of this relationship remain unknown. Carbon isotope data show that Australopithecus bahrelghazali individuals from Koro Toro in Chad are significantly enriched in (13)C, indicating a dependence on C(4) resources. As these sites are over 3 million years in age, the results extend the pattern of C(4) dependence seen in Paranthropus boisei in East Africa by more than 1.5 million years. The Koro Toro hominin fossils were found in argillaceous sandstone levels along with abundant grazing and aquatic faunal elements that, in combination, indicate the presence of open to wooded grasslands and stream channels associated with a greatly enlarged Lake Chad. In such an environment, the most abundant C(4) plant resources available to A. bahrelghazali were grasses and sedges, neither of which is usually considered as standard great ape fare. The results suggest an early and fundamental shift in hominin dietary ecology that facilitated the exploitation of new habitats.
源自 C(4) 植物的食物对于南部和东部非洲早期人类的饮食生态学很重要，但这种关系的起源和地理变异性仍不清楚。碳同位素数据表明，乍得科罗托罗的南方古猿 bahrelghazali 个体的 (13)C 含量显著富集，表明对 C(4) 资源的依赖。由于这些地点的年龄超过 300 万年，因此，这些结果将东非的粗壮傍人对 C(4) 的依赖模式延长了超过 150 万年。科罗托罗古人类化石是在含粘土的砂岩地层中发现的，同时还有大量的放牧和水生动物群元素，这些元素结合在一起表明存在开阔的草原和溪流，与一个大大扩大的乍得湖有关。在这样的环境中，可供 A. bahrelghazali 利用的最丰富的 C(4) 植物资源是草和莎草，而这些通常都不被认为是标准的大型猿类食物。研究结果表明，人类饮食生态学的早期和根本转变促进了对新栖息地的开发。
