Decentralized trade networks existed throughout the pre-Columbian south-central Andes, according to a study. The long-distance exchange of goods and resources is a key factor in the development of complex societies. To improve understanding of ancient trade practices, Marisa Lazzari and colleagues examined the exchange of ceramics, obsidian artifacts, and volcanic rock tools in the Argentinian south-central Andes from 400 BC to AD 1000 using petrography, as well as compositional and archeological analyses; the timeframe marks a period when communities were becoming increasingly sedentary and producing new technologies. The authors found that the volcanic rock tools stemmed from a single source and were traded in only a few locations, whereas obsidian originated from one main location as well as multiple smaller sources and was traded throughout the study region. A comparison of pottery among valleys indicated that the types of clays and fabrics used for pottery differed substantially for ordinary wares but varied little for decorated wares. Furthermore, two distinct types of polychrome pottery decoration were limited to subsections of the study region. According to the authors, the pre-Columbian south-central Andean communities may have supported a multifaceted, decentralized trade network, suggesting that goods, raw materials, and production technologies originated from many locations, in contrast to the traditional theory of a centralized mode of exchange. - Read at PNAS
Article #16-10494: “Compositional data supports decentralized model of production and circulation of artifacts in the pre-Columbian south-central Andes,” by Marisa Lazzari et al.