The world’s oldest stone artifacts from Gona, Ethiopia: Their implications for understanding stone technology and patterns of human evolution between 2.6-1.5 million years ago

Citation: Sileshi Semaw (2000) The world’s oldest stone artifacts from Gona, Ethiopia: Their implications for understanding stone technology and patterns of human evolution between 2.6-1.5 million years ago. Journal of Archaeological Science (RSS)
Internet Archive Scholar (search for fulltext): The world’s oldest stone artifacts from Gona, Ethiopia: Their implications for understanding stone technology and patterns of human evolution between 2.6-1.5 million years ago
Download: http://www.indiana.edu/~origins/X-PDF/Semaw2000.pdf
Tagged: Anthropology (RSS)

Summary

Context: This paper examines the context in which the oldest stone artifacts found and their function. The main findings are from the Gona Paleoanthropological Research Project area of study in the Awash River basin of Ethiopia. Much of the archaeology found in this region is found because of the erosion caused by the drainage of the Awash and its tributaries. The sites focused on in this paper (EG10 and EG12) have been dated to about 2.6 Ma.

Methods and Materials: The chronology of the sites was determined through both 40Ar/39Ar dating of tuffs (volcanic ash solidified into rock) and magnetostratigraphy. Stone artifacts from EG10 and EG12 were classified using a combination of Isaac et al. (1981) and Leakey (1971)’s classification systems to avoid categories that implicate use while still allowing their findings to be comparable to other studies. The composition of raw materials and spatial relationship between stone artifacts was also examined. Further, the findings from the Gona region were compared to sites with similar contexts in the surrounding region.

Results: The chronological methods confirm an age of about 2.6 Ma for EG10 and EG 12. About 70% of the artifacts in both sites were made of fine-grained trachyte implying that there was a preference for this material. The quality of flaked materials found at the Gona sites suggests that the idea of a less sophisticated “pre-Oldowan” industry before 2 Ma is inaccurate. It is argued that between 2.6 and 1.5 Ma there is one Oldowan industry instead of multiple different ones, leaving the author to argue for static development of stone tool technology. The creators of these artifacts is speculated to be Australopithecus garhi. This is not a definite conclusion, but it is the most likely candidate based on available evidence. Cut-mark data from the Bouri region (no evidence at EG10 and EG12) suggest that by 2.5 Ma hominids were using stone artifacts to process animals for food.

Theoretical and Practical Relevance

These findings are crucial to the understanding of when and why stone artifact technology was created. There is an important implication from the artifacts from EG10 and EG12 that there was no sudden improvement in the abilities of hominids to create tools from 2.6-2 Ma. The findings in this paper suggest that the hominids before 2 Ma had some understanding of fracture mechanics and actively discerned between better and poorer qualities of raw materials. Instead, it appears that the hominids that created these early artifacts were as cognitively capable (in regards to the creation of stone technology) as hominids at 2 Ma.