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Edited by James O'Connell, University of Utah, Salt Lake City, UT, and approved April 15, 2013 (received for review December 23, 2012)
Abstract
Hominin fossil evidence in the Turkana Basin in Kenya from ca. 4.1 to 1.4 Ma samples two archaic early hominin genera and records some of the early evolutionary history of Paranthropus and Homo. Stable carbon isotopes in fossil tooth enamel are used to estimate the fraction of diet derived from C3 or C4 resources in these hominin taxa. The earliest hominin species in the Turkana Basin, Australopithecus anamensis, derived nearly all of its diet from C3 resources. Subsequently, by ca. 3.3 Ma, the later Kenyanthropus platyops had a very wide dietary range—from virtually a purely C3 resource-based diet to one dominated by C4 resources. By ca. 2 Ma, hominins in the Turkana Basin had split into two distinct groups: specimens attributable to the genus Homo provide evidence for a diet with a ca. 65/35 ratio of C3- to C4-based resources, whereas P. boisei had a higher fraction of C4-based diet (ca. 25/75 ratio). Homo sp. increased the fraction of C4-based resources in the diet through ca. 1.5 Ma, whereas P. boisei maintained its high dependency on C4-derived resources.
Footnotes
- ↵1To whom correspondence should be addressed. E-mail: thure.cerling{at}utah.edu.
Author contributions: T.E.C., F.K.M., L.N.L., M.G.L., R.E.L., F.H.B., J.A.H., P.K., H.R., K.T.U., and B.A.W. designed research; T.E.C., F.K.M., E.N.M., L.N.L., M.G.L., R.E.L., F.H.B., F.E.G., J.A.H., P.K., H.R., K.T.U., and B.A.W. performed research; T.E.C., F.K.M., L.N.L., M.G.L., R.E.L., F.H.B., F.E.G., H.R., K.T.U., and B.A.W. analyzed data; and T.E.C., M.G.L., F.H.B., and B.A.W. wrote the paper.
The authors declare no conflict of interest.
This article is a PNAS Direct Submission.
See Commentary on page 10470.
This article contains supporting information online at www.pnas.org/lookup/suppl/doi:10.1073/pnas.1222568110/-/DCSupplemental.
Diet of Turkana Basin hominins
Article Classifications
- Biological Sciences
- Anthropology
- Physical Sciences
- Earth, Atmospheric, and Planetary Sciences
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