By allowing the establishment of settled communities, specialised division of labour and technological innovation, the emergence of agriculture is considered one of the most important transitions in the development of human societies.
One of the most significant centres of agricultural importance is the Near East, where barley, wheat and a number of other crops were domesticated around 10,500 years ago. Existing archaeological evidence tells us that the cultivation of barley spread to its ecological limits; covering Europe, North Africa, and Central, South and East Asia over 6,000 years.
Now, new research from the University of Cambridge shows that different kinds of barley, which had different end uses, spread by numerous routes across Eurasia.
Different routes – an indicator of different cultures?
Due to the fact that there were a number of different eastward routes for the spread of the barley population, the study suggests humans were choosing routes based on particular attributes of acting according to environmental adaptation.
Choice and environment, therefore, are crucial factors for the spread of staple foods in prehistory.
These different routes include ones to the north and south of the Iranian Plateau; through the Inner Asian Mountain Corridor in Central Asia, possibly connecting up to the Chinese section of the Silk Road; a high altitude spread on the southern edge of the Tibetan Plateau; a high latitude spread through the northern steppe; two distinct spreads into Japan; and a maritime route from South Asia. As previous research has provided radiocarbon dates, we know when the routes were followed.
Impacting rice-growing in East Asia
Lead author Dr Diane Lister, a researcher at the McDonald Institute for Archological Research at the University of Cambridge, says: “One barley population is widespread, particularly around the coastlines. This population may have travelled eastwards via a maritime route from South Asia, via Southeast Asia. This particular population is made up of winter-sown varieties of barley, which are thought to be important in rice-growing areas of East Asia, where a crop of rice is commonly grown in the summer months, and barley adapted to winter-sowing regimes can be planted after the rice harvest. The development of multi-cropping practices during prehistory is thought to have greatly increased productivity and stability, enabling more complex societies to develop.”
Moulding Tibetan culture
“Another barley population predominates on the high Tibetan Plateau. This barley has a naked grain, making it a particularly attractive staple, as it doesn’t require the pearling process that hulled barley requires for human consumption. Along with the herding of yak, this naked type of barley is an essential for the Tibetan way of life, and their importance are clearly seen in the offerings of naked barley grains and yak butter in Tibetan Buddhist temples around the region. The staple carbohydrate eaten by the Tibetans is tsampa, made from roasted naked barley flour and mixed with salty Tibetan butter tea.”
New findings contribute to conversation around climate change
So what does this mean for today? Lister concludes: “Barley is an extremely hardy crop, able to grow in regions where other crops are unable to grow, and is an important staple in such environments. Understanding the spread of its cultivation during prehistory, and the various factors that affected its establishment in different regions of Eurasia, will contribute towards our understanding of climate change and its current and future effects on agriculture.”
The paper has been published as a part of the Food Globalization in Prehistory project, funded by the European Research Council and awarded to Prof. Martin Jones. Additional funding was provided by a Royal Society International Joint Project grant.