How Tibet was won: The barley mow

THAT agriculture permitted the human population to expand its size is obvious. That it permitted the population to expand its range as well is a more subtle point. But a paper just published in Science, by Chen Fahu and Dong Guanghui of Lanzhou University, in China, and their colleagues, shows a fascinating example of just that. A new crop not only allowed people to colonise the highest reaches of Tibet, but let them do so at a time when the weather was actually getting colder.Archaeology sugges...