In the Nov. 25 SN: Charting lumpy space, Bronze Age movers and shakers, T. rex’s slasher arms, gene editor corrects typos, the Great Pyramid hides a void, mosses chronicle Arctic warming, an itty-bitty insect-inspired robot and more.
BIG MOVES Ancient DNA indicates horse-riding pastoralists called the Yamnaya made two long-distance migrations around 5,000 years ago. One trip may have shaped Europe’s ancient Corded Ware culture, while the other launched central Asia’s Afanasievo culture.
Evidence hierarchies, one version shown, classify types of studies according to the strength of evidence they provide. But a recent paper challenges the assumptions behind these hierarchies.
MIXED ANCESTRY Tiny samples taken from ancient European skulls, in a process shown here, yielded enough DNA for researchers to determine that farmers and foragers interbred in three different regions from 8,000 to nearly 4,000 years ago.