The Mysterious 'Peking Man' Goes to the Dentist
Between 1923 and 1927, archaeologists unearthed a trove of ancient human fossils in Zhoukoudian, China, near Peking – modern-day Beijing. Subsequent excavations through 1937 dug up more than two hundred fossils from forty individuals. But who were these people? Their skeletons were like ours... and yet they weren't. Subtle distinctions made that clear. At first they were called "Peking Man," but the fossils soon received a more formal name: Homo erectus. More Homo erectus have since been found across Asia.
Peking Man surfaced at the dawn of a war-torn era – Japan invaded and occupied China in the late 1930s. Thus, as the archetypes of a newfound species of ancient human, scientists took great care with the fossils. Lead archaeologist Franz Weidenreich even created casts of every specimen and sent them to the American Museum of Natural History for safekeeping. His forward-thinking proved sage, as the original fossils were eventually lost in September of 1941 while destined for the United States, out of occupied China. Some say they fell into the hands of Japanese soldiers. Others say they sunk to the bottom of the Pacific. Regardless, they're lost to science.
Paleontologists returned to Zhoukoudian after World War II, but extensive excavation only turned up a mandible and six teeth. Those six teeth, dated to between 680,000 and 780,000 years ago, are now the focus of a study published to Scientific Reports.
The researchers, based at the Chinese Academy of Sciences and the National Research Center on Human Evolution, are the first to provide new data on Peking Man for over eighty years. Extensively analyzing the teeth with computed tomography (CT) scanning, they identified unique features they say could be used to dentally define future Homo erectus finds in Asia. This would be a nifty advance, as Homo erectus has proven difficult to comfortably recognize based on other characteristics. We know that they were generally slender and tall, with large brow ridges, subtle cheekbones, and voluminous craniums that likely fit sizeable brains.
According to the researchers, what stands out most about the Peking Man teeth are "dendrite-like" enamel-dentine junctions. Essentially, the bottom surface of the teeth resembles a crinkled, branching network of ravines, which differs from other human ancestors. This pattern matches that of other Homo erectus teeth found in Asia. (Below: Peking Man and other Homo erectus teeth seen at the top level are compared to other human ancestors.)
Though all that remains of Peking Man are statues, casts, and teeth, we're still learning a lot from them.
Source: Song Xing, María Martinón-Torres & José María Bermúdez de Castro. "The fossil teeth of the Peking Man." Scientific Reports. volume 8, Article number: 2066 (2018) doi:10.1038/s41598-018-20432-y