image: A large stone tool recovered from sediments in the Ledi-Geraru region of Ethiopia. This sharp edged tool is evidence of early humans making sharp tools around the time that the earliest members of the genus Homo appeared in Ethiopia. view more
Credit: Image courtesy of David Braun.
Researchers report a site containing evidence of systematic flaked tool production that, despite being older than sites attributed to the genus Homo, is technologically distinct from the earliest hominin tool technologies and also divergent from tools made by modern primates. Evidence of production of flaked stone tools by hominins extends back 3.3 million years to before the emergence of the genus Homo, but the earliest known evidence of systematic production of such tools is dated to around 2.55 million years ago and comes from the Oldowan assemblages in Gona, Ethiopia. David Braun and colleagues report the discovery of an additional Oldowan site designated BD 1, which extends the history of systematic tool-making to around 2.61 million years ago. The tools found at BD 1, although more primitive than those at other Oldowan sites, are technologically closer to those Oldowan tools than they are to the tools dating to around 3.3 million years or those produced by modern primates. Flake removal and tool-production technology may have yielded improved access to high-quality foods, and the expanded breadth of diet may have emerged around the same time as environmental changes in Ethiopia. Such changes in early human adaptation may have eased selective pressures on early Homo individuals. According to the authors, the distinctions between these earliest Oldowan assemblages and the industries recovered 3.3 million years ago suggests the possibility that stone tool production was reinvented multiple times in the past.
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Article #18-20177: "Earliest known Oldowan artifacts at >2.58 Ma from Ledi-Geraru, Ethiopia, highlight early technological diversity," by David R. Braun, et al.
MEDIA CONTACT: David R. Braun, George Washington University, Washington, DC; tel: 908-251-4523; e-mail: <david_braun@gwu.edu>
Journal
Proceedings of the National Academy of Sciences