Postprint version. Published in Journal of Archaeological Science, Volume 32, January 1, 2005, pages 423-434.
The definitive version is available at https://doi.org/10.1016/j.jas.2004.11.001.
Eleven Olivella biplicata spire-lopped shell beads from six sites located 250–365 km inland from the Pacific coast of southern California produced AMS dates between 11,200 and 7860 CAL BP. Olivella shell beads were well-documented items of prestige and media of exchange in Native California, and recovery of these examples from inland contexts indicates low-level exchange between resident populations of the coast and the southwestern Great Basin by at least 10,300–10,000 CAL years BP. These findings represent some of the earliest unequivocal evidence for long-distance trade in western North America and push the antiquity of this important form of inter-group interaction back several thousand years earlier than previously thought.
Social and Behavioral Sciences