Cosmic Science

‘Dragon Man’ sparks debate over ancient human species

It’s time to add a new name to the list of ancient human species discovered in the fossil record — or is it?

The latest contender is a species dubbed Homo longi, created on the basis of a skull that was discovered in northern China in the 1930s, hidden for decades, and finally analyzed for a trio of research papers in The Innovation, an open-access journal published by Cell Press.

The almost perfectly preserved fossil is the largest skull ever found representing the genus that includes modern humans (Homo sapiens). Based on the skull’s morphology and geochemical dating techniques, researchers say it’s most likely to have come from a male who was about 50 years old when he died 146,000 years ago.

Researchers at Hebei GEO University have nicknamed the ancient individual “Dragon Man” in recognition of its Chinese origins. The species’ scientific name plays off the Chinese word for dragon (“long”) and the region around Harbin City where the fossil was found — Heilongjiang (“Black Dragon River”) province.

The skull could hold a brain comparable in size to ours, but had larger, almost square eye sockets, thick brow ridges, a wide mouth and oversized teeth. “While it shows typical archaic human features, the Harbin cranium presents a mosaic combination of primitive and derived characters setting itself apart from all the other previously named Homo species,” study author Qiang Ji, a paleontologist at Hebei GEO University, said in a news release.

Ji and his colleagues say the skull’s peculiarities justify its status as a species that’s distinct from Neanderthals and Denisovans and other extinct human ancestors. They even claim that Homo longi is more similar to humans of the Pleistocene era than those others.

“It is widely believed that the Neanderthal belongs to an extinct lineage that is the closest relative of our own species,” said study author Xijun Ni, a professor of primatology and paleoanthropology at the Chinese Academy of Sciences and Hebei GEO University. “However, our discovery suggests that the new lineage we identified that includes Homo longi is the actual sister group of H. sapiens.”

There’s some question about Dragon Man’s status, however.

Several researchers suggest that the specimen is a better fit for the Denisovans, a similarly mysterious, now-extinct human species whose fossils have been found in Asia.

“I think it’s the best skull of a Denisovan that we’ll ever have,” paleontologist Jean-Jacques Hublin of the Max Planck Institute for Evolutionary Anthropology told Science magazine.

Others say Dragon Man should be paired with Dali Man — also known as Homo daliensis or Homo sapiens daliensis. That’s a species whose fossils were found 1,300 miles south of Harbin in China’s Dali County in 1978.

John Hawks, a paleoanthropologist at the University of Wisconsin at Madison, sides with the Dali description.

“Homo longi. It’s such a good name. Dragon people. And an amazing skull discovery. Adds to our knowledge of the Middle Pleistocene in China. But it’s sad that the name is not going to stay,” Hawks tweeted.

Study co-author Chris Stringer, an anthropologist at London’s Natural History Museum, actually sides with Hawks and the other dissenters over his Chinese co-authors.

“While I agree that the Harbin group warrants a distinct species name, I would prefer to place the Harbin and Dali fossils together as H. daliensis,” Stringer tweeted. “I also consider Harbin as a possible Denisovan, although much more work is needed there.”

Human lineages
Researchers try to fit the Harbin skull into the wider spectrum of human fossils. Click on the image for a larger version. (Ni et al. / The Innovation)

Dragon Man’s skull hasn’t undergone DNA sampling, and Stringer said genetic analysis could bring the picture into sharper focus. But Hawks took the debate to a higher level.

“The real question is whether the Chinese later Middle Pleistocene record represents a lineage, and whether we should consider such lineages, like Neandertals, as species. Are Homo daliensis and Homo neanderthalensis the right way to talk?” he wrote. “This is a deep problem upon which scientists have diverse opinions. I think that this new research on the Harbin fossil offers a window to a clearer future.”

Comparisons of genetic and morphological data suggest that the more we know about our extinct ancestors, the fuzzier the picture becomes. “All known archaic groups with ancient DNA evidence interbred. Repeatedly. Seemingly every time they came into contact,” Hawks said.

So it sounds as if the saga of Dragon Man could well become one more tangled tale about the ancient origins of our species. And it turns out that the skull has a back story that’s just as tangled.

The cranium was reportedly found in 1933 during construction work on a bridge in Harbin City, by a Chinese man who worked for Japanese occupation forces as a labor contractor.

“The man was shrewd and realized the potential value of the discovery, probably because the discovery of the first Peking Man cranium in 1929 had attracted huge interest in China,” the researchers wrote in a supplement to one of their research papers. “Instead of passing the cranium to his Japanese boss, he buried it in an abandoned well, a traditional Chinese method of concealing treasures.”

The man never got a chance to recover his find. But before his death, he told his grandchildren about the skull — and they dug it up in 2018. Qiang Ji, one of the lead researchers, found out about the fossil and persuaded the family to donate it to Hebei GEO University’s Geoscience Museum for analysis.

Thus, a piece of Dragon Man survived not only thousands of years of nature’s assaults, but also the hardships of Japanese occupation and World War II, the Chinese Communist Revolution, the Cultural Revolution and the rise of illicit fossil trade in China. And although Dragon Man’s status as a separate species may be the subject of continuing debate, his scientific significance seems sure to endure.

By Alan Boyle

Mastermind of Cosmic Log, contributor to GeekWire and Universe Today, author of "The Case for Pluto: How a Little Planet Made a Big Difference," past president of the Council for the Advancement of Science Writing.

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