Nature human behavior has just published a research highlight written John Carson about work at the Sibilo School Road Site in Kenya done by Nick Blegen, Harvard University, that has recovered large quantities of obsidian along with Middle Stone Age (MSA) tools . The finds are thought to date back at least ∼200 kyr.
As Carson summarizes: “Geochemical analyses demonstrated that the majority of obsidian pieces had their provenance at a source site >160 km away, indicating long-distance transport of raw materials during the MSA.” Previously, East African sites evidencing long-distance resource transport have all be less than <50 kyr old.
Evidently known MSA sites of this age are rare in East Africa. If more sites can be found and excavated, the “big story” usually told about the evolution of human social behavior may need updating: far-reaching resource networks and/or intergroup trade in raw materials could have developed earlier than generally believed in the history of our species. If so, then in Carson’s words: “we may gain greater insight into the timeline of social evolution that eventually led to our modern group behaviours.”
Blegen’s report was just published (unfortunately behind a paywall) in the Journal of Human Evolution. Here is the abstract you will find available there for free:
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