Diet provides critical information about the ecology and environment of herbivores. Hence, understanding the dietary strategies of fossil herbivores and the associated temporal changes is one aspect of inferring paleoenvironmental conditions. Here, we present carbon isotope data from more than 1,050 fossil teeth that record the dietary patterns of nine herbivore families in the late Pliocene and early Pleistocene (3.6 to 1.05 Ma) from the Shungura Formation, a hominin-bearing site in southwestern Ethiopia. An increasing trend toward C4herbivory has been observed with attendant reductions in the proportions of browsers and mixed feeders through time. A high proportion of mixed feeders has been observed prior to 2.9 Ma followed by a decrease in the proportion of mixed feeders and an increase in grazers between 2.7 and 1.9 Ma, and a further increase in the proportion of grazers after 1.9 Ma. The collective herbivore fauna shows two major change points in carbon isotope values at ∼2.7 and ∼2.0 Ma. While hominin fossils from the sequence older than 2.7 Ma are attributed to
New approaches to the study of early hominin diets have refreshed interest in how and when our diets diverged from those of other African apes. A trend toward significant consumption of C4foods in hominins after this divergence has emerged as a landmark event in human evolution, with direct evidence provided by stable carbon isotope studies. In this study, we report on detailed carbon isotopic evidence from the hominin fossil record of the Shungura and Usno Formations, Lower Omo Valley, Ethiopia, which elucidates the patterns of C4dietary utilization in the robust hominin
- NSF-PAR ID:
- 10186358
- Publisher / Repository:
- Proceedings of the National Academy of Sciences
- Date Published:
- Journal Name:
- Proceedings of the National Academy of Sciences
- Volume:
- 117
- Issue:
- 36
- ISSN:
- 0027-8424
- Page Range / eLocation ID:
- p. 21978-21984
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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Paranthropus robustus Broom, 1938 tooth identified to date. While subsequent excavations and research at Gondolin has clarified the geological, temporal, taphonomic, and palaeoecologic context for the in situ deposits, this paper presents the first comprehensive description of the fossil assemblage ‘associated’ with the two ex situ hominins. Analysis of 42 calcified sediment blocks and naturally decalcified sediments excavated from three cubic metres of the Dump A deposits reinforce that the dump contains a heterogeneous aggregation of materials from across the Gondolin sedimentary deposits. A total of 15,250 individual fossil specimens were processed (via sifting or acetic-acid mediated processing of calcified sediment blocks), yielding a faunal record that largely mirrors that described from either (or both) the GD 1 and GD 2 in situ assemblages but includes representatives of four novel mammal groups (Families Cercopithecidae, Felidae, Herpestidae, Giraffidae) not recorded in either in situ sample. While basic assemblage characteristics including primary taphonomic data is presented, analysis and interpretation is limited by the ex situ origin of the sample. Ultimately, these results reinforce that the substantial mining-mediated obliteration of palaeokarstic deposits at Gondolin continue to obscure a clear association between the Gondolin Dump A hominins and any of the sampled and dated in situ deposits.
