Earliest known Oldowan artifacts at >2.58 Ma from Ledi-Geraru, Ethiopia, highlight early technological diversity

Abstract

The manufacture of flaked stone artifacts represents a major milestone in the technology of the human lineage. Although the earliest production of primitive stone tools, predating the genus Homo and emphasizing percussive activities, has been reported at 3.3 million years ago (Ma) from Lomekwi, Kenya, the systematic production of sharp-edged stone tools is unknown before the 2.58–2.55 Ma Oldowan assemblages from Gona, Ethiopia. The organized production of Oldowan stone artifacts is part of a suite of characteristics that is often associated with the adaptive grade shift linked to the genus Homo. Recent discoveries from Ledi-Geraru (LG), Ethiopia, place the first occurrence of Homo ∼250 thousand years earlier than the Oldowan at Gona. Here, we describe a substantial assemblage of systematically flaked stone tools excavated in situ from a stratigraphically constrained context [Bokol Dora 1, (BD 1) hereafter] at LG bracketed between 2.61 and 2.58 Ma. Although perhaps more primitive in some respects, quantitative analysis suggests the BD 1 assemblage fits more closely with the variability previously described for the Oldowan than with the earlier Lomekwian or with stone tools produced by modern nonhuman primates. These differences suggest that hominin technology is distinctly different from generalized tool use that may be a shared feature of much of the primate lineage. The BD 1 assemblage, near the origin of our genus, provides a link between behavioral adaptations—in the form of flaked stone artifacts—and the biological evolution of our ancestors.

Subspheroids in the lithic assemblage of Barranco León (Spain): Recognizing the late Oldowan in Europe

“…While it is not currently possible to positively identify the creators of the earliest stone tools at Gona [4: 627], fossils attributed to Australopithecus garhi found in the Hata Member of the Bouri Formation (Middle Awash) show equivalent age to the EG and OGS sites (2.6-2.5 Ma., Ethiopia) [5,6,7,8,9]. Meanwhile, the newly discovered industry of Bokol Dora 1 (BD 1) (Ethiopia), dated from 2.61 to 2.58 Ma [10], is situated near the Ledi Geraru site, where the most ancient remains of the genus of Homo have been identified (2.8 Ma., [11]). It is noteworthy that, from a technological point of view, the older Lomekwian tools present significant differences from those attributed to the Oldowan techno-complexe [10].…”

“…Meanwhile, the newly discovered industry of Bokol Dora 1 (BD 1) (Ethiopia), dated from 2.61 to 2.58 Ma [10], is situated near the Ledi Geraru site, where the most ancient remains of the genus of Homo have been identified (2.8 Ma., [11]). It is noteworthy that, from a technological point of view, the older Lomekwian tools present significant differences from those attributed to the Oldowan techno-complexe [10]. It therefore appears that more than one species of hominin-not all of the genus Homo-began to rely ever more significantly upon technologies, in an adaptive shift to limit constraints posed by the environment through object mediation.…”

Geological collaboration at paleoanthropological sites in Ethiopia's lower Awash Valley

“…Although the Gona research area was not visited, several geologists involved in the project (Naomi Levin, Jay Quade, and Gary Stinchcomb) were able to provide expert knowledge on regional questions to which the Gona research could contribute. Ramon Arrowsmith, Chris Campisano, Erin DiMaggio (remotely), and Dominique Garello (remotely) led the visit to the Ledi‐Geraru region, including sites of the earliest Homo and Oldowan discoveries . Discussions focused on hypotheses to explain the preservation of 2.9–2.7 Ma strata at Ledi‐Geraru that are not preserved at Hadar, Dikika, or Gona, and the contrast in depositional environments between sites younger than 2.7 Ma.…”

Searching for the emergence of stone tool making in eastern Africa

“…Modern humans rely entirely on technology for their subsistence, and the interaction between technological and biological adaptations has played a key role in the evolution of our lineage. When exactly technology emerged in the fossil record and thus started to shape primate evolution has appealed to researchers since the beginnings of paleoanthropology as a discipline and, as Braun et al (1) show in PNAS, is still today a source of important discoveries.…”

“…While the evidence >3 Ma is not exempt of controversy (see recent reviews in refs. 8 and 9), Braun et al (1) compare the lithic assemblage of BD 1 with that of Lomekwi and conclude that differences are significant enough to maintain a separation between the Lomekwian culture-the name given to the new discovery in Kenya (7)-and the Oldowan, for which BD 1 is now the earliest site. Acceptance of this scenario would imply reconsidering some long-standing paradigms in paleoanthropology.…”