National Geographic : 1992 Mar
kills once thought unique to humans have been discovered among chimpanzees in the wild. In the Taiforest of C6te d'Ivoire, Christophe Boesch (below) and Hedwige Boesch-Achermann observed chimps carefully selecting an appropriate stone to hammer open hard-shelled nuts (left). Mothers share their harvest and teach theiryoung the fine points of tool use. The apes collect the scarce stones and remember where they have left them. The Tai forest chimps also hunt coopera tively. A dominant male (bottom) often leads a group of males andfemales to surround and kill red colobus monkeys. The hunters then share the meat with the larger group.