December 1, 2023

Scientists announced Friday that a massive fossilized skull that is at least 140,000 years old is a new species of ancient man, a finding that could potentially change prevailing views about how – and even where – our species, Homo sapiens , has evolved.

The skull belonged to a grown man with a huge brain, massive brow ridges, deep-set eyes, and a bulbous nose. It had been hidden in an abandoned well for 85 years after a worker came across it on a construction site in China.

The researchers named the new species Homo longi and nicknamed it “Dragon Man” for the region of the Dragon River in northeast China where the skull was discovered.

The team said that Homo longi, not Neanderthals, is the extinct human species that is largely closely related to ours. If confirmed, it would change the way scientists think about the origin of Homo sapiens, which was built up over the years from fossil finds and analysis of ancient DNA.

However, a number of experts denied this conclusion, which was published in three articles that provided a first detailed look at the fossil. Even so, many still thought the find could help scientists reconstruct the human family tree and the origins of modern humans.

All of the experts who checked the data in the studies said it was a great fossil.

“It’s a beautiful thing,” said John Hawks, a paleoanthropologist at the University of Wisconsin-Madison. “It is very rare to find a fossil like this with a face in good condition. You dream of finding this stuff. “

In 1933, a worker discovered the peculiar skull on a bridge construction site in Harbin City. It is likely that the man – whose name was withheld from his family – realized that he had found a scientifically important specimen. Only four years earlier, researchers had found another human-like skull, nicknamed the Peking Man, near Beijing. It seemed to connect the people of Asia with their evolutionary predecessors.

Instead of handing the new skull over to the Japanese authorities, then occupying northeast China, the worker decided to hide it. He didn’t mention the skull to anyone for decades. In a report on the discovery of the fossil, the authors of the new papers speculated that he was ashamed to have worked for the Japanese.

Shortly before his death in 2018, the worker told his family about the fossil. They went to the well and found it. The family donated it to the Geosciences Museum at Hebei GEO University, where scientists could immediately see that it was in excellent condition.

In the papers published Friday, the researchers argued that Homo longi appears to have been a tall adult. His cheeks were flat and his mouth wide. The lower jaw is missing, but researchers conclude from the Dragon Man’s upper jaw and other fossil human skulls that it was likely missing a chin. They say his brain was about 7 percent larger than the average brain of a living person.

The researchers argue that the combination of anatomical features of Dragon Man is not found in any previously named hominin species, the lineage of the two-legged monkey, which is different from other African Monkeys. They later evolved into larger-brained species that paved the way for Homo sapiens to spread around the world.

“It’s distinctive enough to be a different species,” said Christopher Stringer, a paleoanthropologist at the Natural History Museum in London and co-author of two of the three Dragon Man articles.

The scientists analyzed the chemical composition of the fossil and found that it was at least 146,000 years old but not older than 309,000 years.

Today the planet is home to only one species of hominin – Homo sapiens. But Dragon Man existed at a time when a number of drastically different types of hominins co-existed, including Homo erectus – a tall person with a brain two-thirds the size of our own – as well as tiny hominins like Homo naledi in South Africa, Homo floresiensis in Indonesia and Homo luzonensis in the Philippines.

The oldest fossils of Homo sapiens also date from this period. Neanderthals – who shared our large brains and sophisticated toolmaking – ranged from Europe to Central Asia during the time when the dragon man may have lived.

In recent years, research on fossil DNA has also revealed another human-like lineage at this time, the Denisovans. Most of the DNA came from isolated teeth, broken bones, and even dirt. These remains are insufficient to show us what Denisovans looked like.

The most promising fossil found so far, which could be evidence of Denisovans, came from a cave in Tibet: a massive jaw with two powerful molars that is at least 160,000 years old. In 2019, scientists isolated proteins from the jaw, and their molecular makeup suggests they belonged to a Denisovan rather than a modern human or Neanderthal.

This molecular evidence – combined with fossil evidence – suggests that the common ancestors of Homo sapiens, Neanderthals, and Denisovans lived 600,000 years ago.

Our lineage split off on its own, and then 400,000 years ago Neanderthals and Denisovans split up. In other words, Neanderthals and Denisovans were our closest extinct relatives. They even crossed with the ancestors of modern humans, and we now carry bits of their DNA.

But many puzzles still remain from this phase of human history – especially in East Asia. Over the past few decades, paleoanthropologists have found a number of fossils, many of which are incomplete or damaged, and which have some features that make them look like our own species and other features that suggest they are somewhere else in the hominin Family tree.

Katerina Harvati, a paleoanthropologist at the University of Tübingen in Germany who was not involved in the new study, said the dragon man’s skull “could clear some of the confusion”.

To find out how Homo longi fits into the human family tree, the scientists compared its anatomy to 54 hominin fossils. The researchers found that it belongs to a lineage that includes the jaw in Tibet identified as Denisovan.

The skull looked even more like part of a skull discovered in 1978 in Dali County, China, which is 200,000 years old. Some researchers thought the Dali fossil belonged to our own species, while others thought it belonged to an older lineage. Others even named the fossil a new species, Homo daaliensis.

The authors of the new studies argue that the Dragon Man, Tibetan jaw, and Dali skull all belong to a single lineage – one closest to our own species. Homo longi, while having distinctive features, also shared features with us, such as a flat face that was pulled under the forehead instead of protruding like the Neanderthals.

“It is widely believed that the Neanderthals belonged to an extinct lineage that is the closest relative of our own species. However, our discovery suggests that the new lineage we have identified belongs to the Homo longi, the actual sister group of H. sapiens, ”said Xijun Ni, co-author of the studies and paleoanthropologist at the Chinese Academy of Sciences and Hebei GEO University in a press release.

These conclusions fuel debate among paleoanthropologists – including the authors of the new publications.

Part of the debate concerns the name Dragon Man. Scientists follow strict rules when naming new species. To do this, Dragon Man would have to share a name with the Dali skull, if they are as similar as the authors claim.

“From my point of view, it is a distinct species that I would rather call Homo daaliensis,” said Dr. Stringer.

Other experts thought that the resemblance between the Tibetan jaw with the Denisova-like proteins and Harbin’s skull hinted at the true identity of Dragon Man.

“When I first saw the picture of the fossil, I thought, now we finally know what Denisova people looked like,” says Philipp Gunz, paleoanthropologist at the Max Planck Institute for Evolutionary Anthropology in Leipzig.

Karen Baab, a paleoanthropologist at Midwestern University in Arizona, agreed, “Harbin is better understood as a Denisovan.”

A number of references point in this direction. The tooth on the upper jaw of Dragon Man has the same massive shape as that of the Denisova jaw, which was found in Tibet, for example. Both are missing a third molar. Dragon Man was also living in Asia at the same time that Denisova DNA tells us they were in the same place.

Even if Dragon Man is a Denisovan, there would be more puzzles to solve. The DNA of the Denisova people clearly shows that their closest relatives were Neanderthals. The new study, which is instead based on fossil anatomy, instead shows that Homo longi and Homo sapiens are more closely related than they are to Neanderthals.

“I think the genetic data is more reliable than the morphological in this case,” said Bence Viola, a paleoanthropologist at the University of Toronto who was not involved in the new study.

“Obviously something is wrong,” confirmed Dr. Stringer. “The most important thing is the recognition of a third human lineage in East Asia with its own distinctive combination of characteristics.”

One way to solve the mystery of Dragon Man is to extract DNA from his remarkable skull. Dr. Stringer said he was ready for more surprises.

“It’s going to be a more complicated storyline.”