The transition to a barley-dominant cultivation system in Tibet: First millennium BC archaeobotanical evidence from Bangga

Early agropastoral settlement and cultural change in central Tibet in the first millennium BC: excavations at Bangga

“…The presence in central Tibet of both Eastern and Western Asian crops during the second and first millennia BC should be understood in the wider context of the trans-Eurasian exchange of cereal crops (Frachetti 2012;Liu et al 2019). Nevertheless, the distinction in cropping systems between Bangga and Changguogou should be considered in the context of assemblageformation processes, which tend towards routine food preparation of staple grains (Tang et al 2021). It could also be driven by a variety of social, economic and ecological factors, including issues related to crop cold-tolerance, flexibility in crop flowering times and the possibility of long-distance exchange of grains (d'Alpoim Guedes et al 2015;Liu et al 2017;d'Alpoim Guedes 2018;Song et al 2021), but also culinary choice, a potential driver that has been discussed elsewhere (Liu et al 2016).…”

“…These include 128 barley grains and 16 wheat grains. Relatively intact barley rachises were recovered in 2018, indicating the practice of barley-dominant agriculture at Bangga (Tang et al 2021). The majority of wheat and barley remains from Bangga were retrieved from stone enclosure F1 in the north of the site, suggesting that F1 may be a domestic structure.…”

Interpreting Diachronic Size Variation in Prehistoric Central Asian Cereal Grains

“…Barley rapidly spread with the Founder Crops across Europe and West Asia, reaching southern Central Asia by 6,500 BC (Harris, 2010), the eastern edge of the Iranian Plateau at Mehrgarh by 6,000 BC (Costantini, 1984), into the Ganges Plain (Liu et al, 2017) and north all the way to the Altai Mountains by 3000 BC (Zhou et al, 2020). Barley entered the economic system in Japan by the fifth century AD (Leipe et al, 2017) and developed into a monocropping system in the Tibetan highlands by the early first millennium BC (Tang et al, 2020). Barley remained the most important grain crop across Europe and West Asia from the earliest cultivation systems until the intensification of irrigation and crop-rotation cycles around the mid-first millennium BC, when free-threshing wheat (Triticum aestivum) started to increase in prominence across both Europe and West Asia and hulled varieties largely replaced naked forms of barley (Lister and Jones, 2013;Spengler, 2015).…”

“…Barley remained the most important grain crop across Europe and West Asia from the earliest cultivation systems until the intensification of irrigation and crop-rotation cycles around the mid-first millennium BC, when free-threshing wheat (Triticum aestivum) started to increase in prominence across both Europe and West Asia and hulled varieties largely replaced naked forms of barley (Lister and Jones, 2013;Spengler, 2015). In the high-elevation mountain regions of the Tien Shan or the Himalaya, naked barley has been the dominant crop for nearly four millennia (Motuzaite Matuzeviciute et al, 2020aTang et al, 2020).…”

“…Greater rates of evolutionary adaptation tend to occur at the margins of a species' range (Mayr, 1942). One example of this range edge effect for barley comes from the rapid adaptation of qingke barley to high elevation Tibet (Tang et al, 2020), often argued to have occurred through hybridization and gene transfer from native wild barleys (Dai et al, 2012;Zeng et al, 2015), although recent research is suggesting rapid evolution of a specific ecotype, and the subsequent feralization to brittle-rachis forms outside cultivation (Zeng et al, 2018).…”