The enigmatic species of ancient humans known simply as Denisovans now appear to have a face, due to a study that has linked our long-lost cousin species to fragments of genetic material found in a fossilized skull that had been hidden by its discoverer—fearful of the political consequences that might result from how he discovered it—for over eighty years.

Although it wasn’t studied until being delivered to China’s Hebei GEO University in 2018, the skull of the individual belonging to the species called Homo longi is a strange one: the fossil was reportedly found in 1933 by a laborer working on the Manchukuo National Railway in the State of Manchuria, a region that is now part of northeastern China.

Having initially hid the skull in an abandoned well from the Manchukuo authorities, following World War II the worker was still unable to report the find, first to the invading Soviets and later the Chinese Communist authorities since he was afraid to reveal his work on the railway: as a project sponsored by Imperial Japan, his involvement could have lead to persecution by either of the incoming regimes. In 2018 the worker’s grandson learned of the skull’s existence, and was persuaded to donate the fossil to Hebei GEO University.

The 85 years between its reported discovery by the Songhua River and 2018 revelation made dating the fossil difficult, but it was determined that the skull was between 296,000 to 62,000 thousand years old, with a minimum age of 146,000 years, placing it well within the same era as the Denisovans. Further analysis determined that the skull did appear to have originated in the region reported by the worker, now part of China’s province of Heilongjiang (“Black Dragon River” in Mandarin), of which the species is named after, and leading to the skull’s nickname of ‘Dragon Man’.

That brings us to the Denisovans: until now, what little we know of this enigmatic species has largely been derived from genetic material extracted from fragments of their remains scattered across Asia, with the first being a single fingerbone excavated in 2008 from Denisova Cave in the Siberian Altai Mountains—indeed, a formal species name has not been applied to these people, due to the lack of even a partial fossil collection.

Denisovans appear to have lived between 285,000 to 25,000 years ago across the Asian continent, with partial remains found in locations as diverse as the aforementioned Denisova Cave, Baishiya Karst Cave on the edge of the Tibetan Plateau, and as far south as the Tam Ngu Hao 2 Cave in northern Laos. Their genetic material, some of which survives as part of the DNA of modern humans, indicates that they had dark eyes, hair and skin, and had bodies with a broad-shouldered Neanderthal-like build.

Although an analysis conducted at the Chinese Academy of Sciences of H. longi’s skull yielded no surviving DNA, the fragments of 95 different proteins were extracted from leftover amino acid samples found within the fossil, four of which were distinct to those held by Denisovans—enough of a link for the Dragon Man and the Denisovans to be considered the same species.

Additionally, “the extraction of ancient proteins and ancient DNA from the Harbin skull further confirms that Denisovans were widely distributed in Asia during the Middle Pleistocene” between 789,000 and 130,000 years ago, remarked Xiujie Wu, a paleoanthropologist with the Institute of Vertebrate Paleontology and Paleoanthropology who was not directly involved in the study.