Contents

13 February 2015
Vol 347, Issue 6223

About The Cover

Cover image expansion

COVER Who are the Tibetans? New findings from disparate fields are revising notions about how people settled the cold, high, and dry Tibetan Plateau, one of the most forbidding environments that humans call home. Like many questions of geography and migration, the prehistoric conquest of the "roof of the world" has political overtones. See page 708.
Photo: © Blaine Harrington III/Corbis