title: Nomadic ecology shaped the highland geography of Asia's Silk Roads.
abstract: There are many unanswered questions about the evolution of the ancient 'Silk Roads' across Asia. This is especially the case in their mountainous stretches, where harsh terrain is seen as an impediment to travel. Considering the ecology and mobility of inner Asian mountain pastoralists, we use 'flow accumulation' modelling to calculate the annual routes of nomadic societies (from 750 m to 4,000 m elevation). Aggregating 500 iterations of the model reveals a high-resolution flow network that simulates how centuries of seasonal nomadic herding could shape discrete routes of connectivity across the mountains of Asia. We then compare the locations of known high-elevation Silk Road sites with the geography of these optimized herding flows, and find a significant correspondence in mountainous regions. Thus, we argue that highland Silk Road networks (from 750 m to 4,000 m) emerged slowly in relation to long-established mobility patterns of nomadic herders in the mountains of inner Asia.
authors.affiliation: SAIE Laboratory, Department of Anthropology, Washington University in St. Louis, 1 Brookings Drive, CB 1114, St. Louis, Missouri 63130, USA.
authors.forename: Michael D
authors.initials: MD
authors.lastname: Frachetti
authors.affiliation: SAIE Laboratory, Department of Anthropology, Washington University in St. Louis, 1 Brookings Drive, CB 1114, St. Louis, Missouri 63130, USA.
authors.forename: C Evan
authors.initials: CE
authors.lastname: Smith
authors.affiliation: University Libraries, Washington University in St. Louis, 1 Brookings Drive, CB 1061, St. Louis, Missouri 63130, USA.
authors.forename: Cynthia M
authors.initials: CM
authors.lastname: Traub
authors.affiliation: Institute of Archaeology, University College London, 31-34 Gordon Square, London WC1H 0PY, UK.
authors.forename: Tim
authors.initials: T
authors.lastname: Williams
mesh_terms: D000531:Altitude; D000822:Animal Husbandry / Q000266:history*; D000818:Animals; D001106:Archaeology; D001208:Asia; D005843:Geography / Q000191:economics; D065948:Grassland; D049690:History, Ancient; D063426:Human Migration / Q000266:history*; D058751:Livestock; D012621:Seasons; D047011:Silk / Q000191:economics / Q000266:history*; D014195:Travel / Q000191:economics / Q000266:history
chemical_list: D047011:Silk