Archaeologists are ecstatic as they study a 24,000-year-old human bone fragment that's been discovered on Ishigaki Island in southern Okinawa Prefecture. The Okinawa Prefectural Museum and Art Museum is among those poring over the bone piece found in the Shirahosaonetabaru cave. Officials believe the bone fragment is part of a rib. The bone's already been tested using direct dating, and scientists now say the latest bone discovery is 4,000 years older than any other bone found in Japan. The testing, using radiocarbon dating, is being supervised by archaeologists at the University of Tokyo to determine the age of the...