NORWICH, ENGLAND—Surveys of areas of the Western Sahara under the control of the Sahrawi Arab Democratic Republic and examination of satellite images on Google Earth have identified dolmens, structures made of piled rocks, and stones arranged on the ground in shapes of crescents, circles, lines, and rectangles, according to a Live Science report. However, little recent excavation has been carried out in the region because of security problems. Joanne Clarke of the University of East Anglia and independent researcher Nick Brooks, who reviewed work done there between 2002 and 2009, said that the structures could mark the locations of graves. Few artifacts recovered from these desert sites can be radiocarbon dated, although human burials at two tumuli were dated to about 1,500 years ago. To read about a groundbreaking discovery made in nearby Morocco, go to “Homo sapiens, Earlier Still.”