A long-standing mystery about a chimpanzee civil war might have finally been solved, thanks to social networking. Back in 1971, a group of chimpanzees in Tanzainas Gobe Stream national park suddenly split into two factions and spent the next four years trying to wipe each other out. Researcher Jane Goodall, who has monitored activity in the park for the last 50 years was at a loss to work out what had caused the violent shift in the groups dynamic.