UPPSALA, SWEDEN—Two 500,000-year-old teeth from “Peking Man” were found in the 1920s by Otto Zdansky of Uppsala University in caves in Zhoukoudian near Beijing. The teeth, along with a third unearthed in the 1950s, were housed in the Museum of Evolution in Uppsala. Other material from the excavation that were housed in China were lost during World War II. But some of the boxes of materials sent to the university from the excavations at Zhoukoudian were never unpacked. Then in 2011, Per Ahlberg, Martin Kundrat, and Jan Ove Ebbestad started going through the boxes that were in storage at Uppsala University and found a Homo erectus tooth. They invited paleontologists Liu Wu and Tong Haowen of the Institute of Vertebrate Palaeontology and Palaeoanthropology (IVPP) in Beijing to study it. “It is a spectacular find. We can see numerous details that tell us about this individual’s life. The crown of the tooth is relatively small, which indicates that it belonged to a woman. The tooth is quite worn, so the individual must have been quite old when she died. In addition, two large chips have been knocked out of the enamel, as if hit by something, or perhaps by biting into something really hard such as a bone or a hard nut. At least one of the chips was old when the individual died, since it is partly worn down,” Ahlberg said. “The lost materials of the Peking Man remain one of palaeontology’s greatest mysteries and most tragic losses,” he added. To read more about the lost fossils, see "Searching for Peking Man."