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The enigmatic skull, which recovered from the bottom of a well in northeastern China in 2018, sparked a conspiracy when it was not consistent with previously known prehistoric humans. Now, the scientists say they have found evidence of where the fossil fits, which could be an important part of another mysterious evolutionary puzzle.
After some unsuccessful attempts, researchers extracted genetic material from the fossilized skull and linked it to an enigmatic group of early humans known as Dragon Man and known as Denisovan. Fossilized bone fragments of Denisoba have been previously discovered and identified using ancient DNA. However, the small size of the specimen made little thought about what the shadowy population of this ancient hominin would look like, and the group has never been assigned an official scientific name.
Scientists usually consider skulls with ridges and ridges of the skull. The best kind of fossil remains to understand the shape and appearance of extinct hominin species. New findings can effectively make a face to Denisovan’s name if confirmed.
“I really feel like I’ve cleared up some of the mysteries surrounding this population,” said Qiaomei Fu, a professor at the Institute of Paleontology and Paleontology, part of Beijing’s Chinese Academy of Sciences and the lead author of the new study. “Fifteen years later, we know the first Denisovan skull.”
Denisovan was first discovered in 2010 from ancient DNA found in the pinky fossils in the Denisova Caves in the Altai Mountains of Russia by a team including FU, a young researcher at the Max Planck Institute in Leipzig, Germany. More excavated in the caves, from which groups acquire their names and continue to be added to the still incomplete paintings elsewhere in Asia.
The new study, described in two scientific papers published Wednesday, is “undoubtedly, if not the biggest paleontological paper of the year,” and encourages discussion in the field “for quite some time.”
The findings helped bridge the gap between the days when humans weren’t just roaming the planet, and taught scientists more about modern humans. Our species once coexisted for tens of thousands of years, and bred with both Denisovan and Neanderthals before the two were extinct. Most humans today have the genetic heritage of those ancient encounters. Although the fossils of Neanderthal have been the subject of research for over a century, slight details are known about our mystical Denisovan cousin, and skull fossils can be very clear.
Workers in Harbin, northeastern China, discovered the skull of a dragon man in 1933. The man who was building a bridge over the Songhua River when this part was under Japanese occupation took the specimen home and kept it at the bottom of the well for storage.
The man never recovered his treasure, and the skull still had one tooth on his upper jaw, but it was unknown to science for decades until his relatives learned it before his death. His family donated the fossils to Hebei Geo University, and researchers first described it in a series of studies published in 2021, finding that the skull was at least 146,000 years ago.
Researchers argued that the fossils deserved the name of a new species given the unique nature of the skull, and named Homo Longi. This comes from the Black Dragon River, the province where the head jang, or calaum, was discovered. While some experts at the time assumed that the skull could be denigerum, others grouped the skulls in a cache of difficult-to-classify fossils found in China, resulting in intense debate and molecular data from the fossils being particularly valuable.
Given the age and backstory of the skull, Fu said he knew it would be difficult to extract ancient DNA from fossils. “In the world that has ancient DNA, there are only bones from over 100,000 (years) of sites,” she said in an email.
Fu and her colleagues attempted to retrieve ancient DNA from six samples taken from the Dragon Man’s surviving teeth and skull belly bones.
The team also attempted to retrieve genetic material from the dental calculus of the skull. In other words, the teeth were left with a hard layer formed and the gank that could hold DNA from the mouth. From this process, researchers were able to retrieve mitochondrial DNA. This is less detailed than nuclear DNA, but one new paper published in the journal Cell revealed a link between the sample and the known denisova genome.
“Mitochondrial DNA is just a small part of the total genome, but it can convey much to us. There is a limit to its relatively small size compared to nuclear DNA, and it is inherited only from the matrixiniel side, not from the biological parent,” Mcrae said.
“So, without nuclear DNA, this individual could create a case of being a hybrid with Denisovan’s mother, but I think the scenario is much lower than this fossil belonging to the complete Denisovan,” he added.
The team suggested that another paper published Wednesday in the journal Science suggested that the analysis suggests that the Dragon Man skull belongs to the Denisoba population.
Together, “These papers enhance the impact of establishing Harbin’s skull as denigzag,” Hu said.
The molecular data provided by the two papers is potentially very important, according to anthropologist Chris Stringer, a research leader on human origin at the Museum of Natural History in London.
“I have been working with Chinese scientists on new morphological analysis of human fossils, including Harbin,” he said. “Coupled with our research, this work raises the possibility that Harbin is the most complete fossil of Denisovan ever discovered.”
However, Xijun Ni, a professor at Beijing’s Institute of Vertebrate Paleontology and Paleontology, was working with Stringer on the first Dragon Man study, but said he was cautious about the results of the two papers, as it was not the latest research and some of the DNA extraction methods used were “experiments.” NI also said that although DNA was obtained from the calculus of the surface teeth, it felt strange that it was not the inside of the teeth or the inside of the abdominal bone, given that the calculus appears to be exposed to potential contamination.
Nevertheless, he added that he believes that the skulls and other fossils identified as Denisovan are likely from the same race.
The goal in using the new extraction approach was to restore as much genetic material as possible, Fu explained, adding that the dense crystal structure of dental calculations may help prevent host DNA from being lost.
Friedwellker, an associate professor of biomolecular paleoanthropology at the Globe Institute, University of Copenhagen, Denmark, showed that the protein signature FU and her team have recovered. Welker recovered Denisovan proteins from other candidate fossils, but was not involved in this study.
“The Harbin skull, currently linked to Denisovan based on molecular evidence, can certainly compare the majority of human fossil records with known Denisovan specimens based on morphology,” he said.
Denisovan’s name and face
The Dragon Man skull is linked to Denisovan based on molecular evidence, making it easier for paleontologists to classify other potential Denisovan relics from China and elsewhere. McRae, Ni and Stringer said they believe Homo Longi is likely to become the official species name for Denisovans, despite other names being proposed.
“Renaming the entire suite of Denisovan’s evidence as Homo Longi is a bit of a step, but it’s been in good condition since the Scientific name Homo Longi technically first existed,” Mcrae said. However, he added that he doubts Denisovan’s unofficial name will always go anywhere and anywhere, suggesting that it could be a species profile as Neanderthals are in Homo Neanderthals.
The findings also allow us to say a little more about what Denisovan looked like, assuming that the Dragon Man skull belongs to a typical individual. According to McRae, ancient humans would have had very strong brow ridges. Overall, Denisovan would have had a robust blocky appearance.
“Like the famous image of Neanderthals dressed in modern clothing, they could still be recognized as ‘humans,” McRae said.
“They are still our more mysterious cousins, slightly less than before,” he added. “There’s still a lot to do to get a sense of who Denisovan is and how they relate to us and other humanity.”
