July/August 2012 Issue

IRAQ: Understanding the climate of the past often helps with interpretation of archaeological discoveries. A review of ancient documents written between A.D. 816 and 1009 reveals a pattern of unusual weather occurrences in Baghdad, particularly cold-weather events such as hailstorms, frozen rivers, and snow during a certain period of the 10th century. Although it snowed in Baghdad in 2008, such cold snaps are rarer today.

PERU: Some pre- Columbian South Americans lived in groups called allya and buried their dead together in monuments called chullpas. At the site of Tompullo 2, scientists gathered genetic material from six chullpas to determine how the people in each were related. Results show that the ancient Andeans are closely related to modern ones, and that chullpas were family graves based around a male lineage, suggesting allya were structured the same way. But not necessarily— one grave contained the remains of three related men with different paternal lineages.

ETHIOPIA: Dating to around 3.4 million years ago, foot bones show that Australopithecus afarensis—"Lucy" and her kin—had company. The new foot appears to be substantially different from an A. afarensis foot. Where Lucy had feet adapted to more-or-less humanlike walking, this new hominin would have been adept at climbing trees. Until now, A. afarensis was thought to be the only hominin in the region at the time.