An Analysis of Stone Balls from Archeological Sites

Environmental & Science Education, STEM, Archeology, Models, Nature of Science, History of Science, Society, Culture, Computation

Ed Hessler

This news report by news intern Phie Jacobs in the journal Science (September 5, 2023) for general readers may be read here; the original technical paper on which the news report is based may be read here.  The latter includes information about the authors, their contributions, the abstract, introduction which includes background and the question, a map you will find useful, diagrams/illustrations, and a discussion. It is always of interest to compare the titles.

These three sentences from the abstract provide my introduction.  "Spheroids are one of the least understood lithic items yet are one of the most enduring, spanning from the Oldowan to the Middle Palaeolithic. Why and how they were made remains highly debated. We seek to address whether spheroids represent unintentional by-products of percussive tasks or if they were intentionally knapped tools with specific manufacturing goals."

Jacobs describes how scientists at the Computational Archaeology Laboratory of the Hebrew University of Jerusalem (HUJI) developed new, sophisticated, 3D analysis software that can measure angles on the surface of a spheroid, calculate the level of surface curvature, and determine the object’s center of mass. They used this software to analyze 3D scans of 150 limestone spheroids from the northern Israeli site."  From this, a  reconstruction on how they might have been made followed--"as best they could."

For the researchers the analysis hints that early toolmakers had an appreciation for both symmetry and beauty." Of course, a dissenting view with reasons and suggestions to further buttress the case, is presented. The Jacobs reporting includes an image at the top that will tell you why this analytic approach was required. The spheroids consist of limestone. Two other definitions may be helpful: Acheulean and symmetry. 

Information about writer Phie Jacobs is at the end of his report.