Letters from the May 6, 2006, issue of Science News

Same old grind

“Ancient Andean Maize Makers: Finds push back farming, trade in highland Peru” (SN: 3/4/06, p. 132) remarks on maize starch granules being “consistent with” stone grinding. The presence of lowland arrowroot on one tool is consistent with trade, but it is equally consistent with a wandering hunter grabbing a root in the midlands and bringing it home.