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Post by Admin on Jun 25, 2021 20:06:15 GMT
The Harbin cranium was discovered in mysterious circumstances in Harbin City in the Heilongjiang province of China in the 1930s. The man who unearthed it reportedly hid it in a well, only revealing its location on his deathbed. It was recovered in 2018 and has now been analysed for the first time. “It’s a really amazing discovery. It is one of the most complete crania I have ever seen,” says Xijun Ni at the Chinese Academy of Sciences, who was part of the team that studied the fossil. It is also the largest known Homo skull ever found. “This is biggest human skull I’ve seen – and I’ve seen a few,” says Chris Stringer at the Natural History Museum, London, who was also a member of the team. The researchers estimate that the skull belonged to a man who was about 50 years old when he died, between 146,000 and 296,000 years ago. Its features are a mix of those seen in archaic and modern humans. It has thick brow ridges, for example, yet “the face looks so much like a bigger version of a modern human face”, says Stringer. Its brain size was similar to ours too. “It’s got such an interesting combination of features,” says Stringer. “The morphology shows that this is definitely a distinct lineage in eastern Asia. It’s not Neanderthal and it’s not Homo sapiens, it’s something quite distinctive,” says Stringer. One possibility is that the Harbin fossil is a Denisovan. This mysterious group of extinct humans was first identified a decade ago from DNA in a finger bone found in the Denisova cave in Siberia, Russia. The Denisovans were closely related to the Neanderthals, and lived in Asia for hundreds of thousands of years. They also interbred with H. sapiens. A few additional Denisovan fossils been identified in recent years, including a jawbone at least 160,000 years old from Tibet, known as the Xiahe mandible. But Denisovan skulls have proved more difficult to track down: the Harbin cranium may be one of the strongest candidates yet found, bringing us closer to our first definitive glimpse of a Denisovan face. When a team lead by Ni constructed a family tree to establish the ancestral lineage of the Harbin fossil, based on physical characteristics of the fossils, they found that it was most closely related to the Xiahe mandible. Interestingly, both of these fossils have massive teeth. John Hawks at the University of Wisconsin-Madison agrees. “My opinion is that… this is more than likely Denisovan.” The clincher would be if DNA could be extracted from the Harbin cranium, something that may be done in future. “I think it’s possible that Harbin will turn out to be a Denisovan skull, the most complete one,” says Stringer. “That’s something we’ll have to test with DNA, but that’s probably a long shot because it’s at least 146,000 years old.” Although there is excitement at the possibility that the Harbin skull might be Denisovan, there is less enthusiasm about the decision to officially name it as a new species. Five members of the research team, including Ni – but not Stringer – co-authored an accompanying paper in which they established it as H. longi. Many researchers prefer not to name new human species for several reasons, including the fact that DNA evidence shows that “species”, including Neanderthals and Homo sapiens, interbred. Most academics prefer to refer to the Denisovans as a “group” or “lineage” rather than a distinct species. “You can be a separate lineage and not have achieved species status,” says Bailey. “I do think that the one type of analysis they use isn’t conclusive enough to say that there’s a new species,” says Sheela Athreya at Texas A&M University. Journal references: The Innovation, DOI: 10.1016/j.xinn.2021.100130 and DOI: 10.1016/j.xinn.2021.100132
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Post by Admin on Jun 26, 2021 3:37:28 GMT
Late Middle Pleistocene Harbin cranium represents a new Homo species Qiang Ji Wensheng Wu Yannan Ji Qiang Li Xijun Ni Published:June 25, 2021 DOI:https://doi.org/10.1016/j.xinn.2021.100132 In eastern Asia, several Middle-Late Pleistocene human fossils, such as the Dali, Jinniushan, Hualongdong, and Harbin crania, evidently resemble each other and are phylogenetically closer to H. sapiens than to H. neanderthalensis or other archaic humans.1 The Harbin cranium is the best preserved of this group. It shows a mosaic combination of plesiomorphic and apomorphic features. Here, we suggest that the Harbin skull should be recognized as a new species of Homo. Systematic biology Order Primates Linnaeus, 1758 Suborder Anthropoidea Mivart, 1864 Superfamily Hominoidea Gray, 1825 Family Hominidae Gray, 1825 Tribe Hominini Gray, 1825 Genus Homo Linnaeus, 1758 Homo longi sp. nov. Ji & Ni Figure 1 The Harbin cranium (HBSM2018-000018(A)) Etymology The species name is derived from the geographic name Long Jiang, which is a common usage for the Heilongjiang Province and literally means “dragon river.” Holotype An undistorted and almost complete cranium (HBSM2018-000018(A)). The specimen was donated to Hebei GEO University (HGU) in 2018. The repository is the Geoscience Museum of HGU, Shijiazhuang, China. The holotype of Homo longi sp. nov. has been deposited in the ZooBank database (http://zoobank.org/) with Life Science Identifier urn:lsid:zoobank.org:act:B2179E99-5CDF-44DA-A1F1-A2BBAFB47185. Locality and age Middle Pleistocene, upper part of the Upper Huangshan Formation (∼138–309 ka), near the Dongjiang Bridge in Harbin City, Heilongjiang Province, China. A reliable minimum U-series age is 148±2 ka.2 Diagnosis Differing from all the other named Homo species by presenting a combination of the following features: an extinct hominin massive in size with a very large maximum cranial length, nasio-occipital length and supraorbital torus breadth; cranial vault long and low, with receding frontal, evenly curved parietal contour, and rounded occipital contour; no sagittal keeling; upper face extremely wide, with large and almost square orbits; facial height low relative to the upper facial breadth; supraorbital torus wide, massively developed, and gently curved. Interorbital area wide, with a flat and recessed nasal saddle; cheekbone flat and low, with a shallow canine fossa; no maxillary inflation; nasal aperture wide inferiorly and almost triangular; cranial lateral walls nearly parallel, without lateral expansion at the parietal prominence; occipital torus weak, without suprainiac fossa; palate in U-shape, with shallow and thick alveolar bone; incisor sockets angled, suggesting the presence of alveolar prognathism; mastoid process large, inclining forward and inward; tympanic plate anteroinferior surface flat and moderately thick; styloid process fused to the tympanic.
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Post by Admin on Jun 26, 2021 6:49:14 GMT
Comparative morphology The Harbin cranium is massive in size, larger than all other known-archaic humans.1 The endocranial capacity is estimated as ∼1,420 ml, falling in the range of H. sapiens and Neanderthals, and larger than other Homo species such as H. erectus, H. naledi, H. floresiensis, and even some H. heidelbergensis/H. rhodesiensis.
The Harbin cranium is relatively long and low and lacks the globularity of the modern human braincase. The frontal is receding, and the parietal is evenly curved. The supraorbital torus is massive and continuous, and the postorbital constriction is much deeper than in H. sapiens. The large endocranial volume of Harbin cranium is reflected in more parallel side walls of the temporals and parietals, but the cranium lacks the H. sapiens-like parietal bosses. The thickness of the supraorbital torus is proportionally much greater than that of later H. sapiens. The Harbin cranium does also share some similarities with H. sapiens.
Its facial height is very low, the zygomaxillary region is flat with a shallow canine fossa, and the overall prognathism is reduced, showing a similar condition to recent humans. The basion angle-nasion angle plot indicates that the Harbin cranium is much closer to H. sapiens than to H. erectus and H. heidelbergensis/H. rhodesiensis, and the face is hafted onto the braincase with reduced prognathism. In its combination of traits Harbin is more like fossils attributed to early H. sapiens, such as Jebel Irhoud 1 and Eliye Springs, than to later members of our lineage.
There are very small angular tori inferiorly on the parietals, proportionally much smaller than those in H. erectus. The occipital has a relatively rounded lateral profile, presenting a less flexed form than that typical of H. erectus. The occipital torus is almost absent, much weaker than in H. erectus. The face is relatively low, and lacks the anterior projection typical of H. erectus. Postorbital constriction is also proportionally shallower than in most members of H. erectus. The tympanic bone of the Harbin cranium is flat and thin, and lacks the robusticity typical of H. erectus.
The Harbin cranial vault lacks the parasagittal flattening and keeling found in some H. heidelbergensis/H.rhodesiensis. The occipital bone lacks the angulation and strong transverse torus. The face is relatively low, and lacks the anterior projection as in the Broken Hill, Petralona, Bodo, and Arago fossils. Postorbital constriction is also proportionally shallower than in most members of H. heidelbergensis/H. rhodesiensis. The cheekbones do not show the Neanderthal-like inflation found in large specimens of H. heidelbergensis/H. rhodesiensis.
Compared with Neanderthals, the Harbin cranium also has a massive and curved supraorbital torus, with strong lateral thickness. Postorbital constriction of the Harbin cranium is proportionally deeper than those of Neanderthals. The occipital surface lacks both a “chignon” and a centrally developed suprainiac fossa typical of Neanderthals. The zygomaxillary angle is somewhat larger than in Neanderthals and approaches that of H. sapiens, indicating a less medial projection of the midface. The zygomaxillary area is flattened and without maxillary inflation. The single molar tooth is huge by Neanderthal standards.
H. antecessor is much smaller than the Harbin cranium, with weaker supraorbital development, much smaller endocranial volume, narrower upper face width, and much smaller M.2
Differing from the Dali cranium, Harbin lacks sagittal keeling and presents proportionally larger and almost square orbits, overall thinner and smoother supraorbital tori with a weaker superciliary arch, and weaker lateral thinning. The Jinniushan cranium has a similar cranial capacity (∼1,390 ml) to the Harbin, but is more gracile. Harbin has a proportionally broader anterior maxillary region, larger and squarer orbits, thicker supraorbital tori, and a larger molar than the Jinniushan. The recently described Hualongdong skull belonged to an adolescent individual. It resembles the Dali cranium and differs from the Harbin in presenting strong frontal sagittal keeling and thick supraorbital tori with a strong superciliary arch. Compared with the Harbin and Dali, the Hualongdong skull has a proportionally narrower and longer face, narrower nasal aperture, and shallower canine fossae. Some of these differences may be due to the younger age of the Hualongdong individual. The Xuchang cranium has a much larger cranial capacity, but a wider, lower braincase with reduced bone thickness. Its supraorbital tori are much thinner, and its mastoid processes are much smaller. The supraorbital torus of the Maba partial cranium is thinner and more curved, the nasal bone more projecting, and the frontal and parietal are thinner than in the Harbin cranium. The orbital shape and projecting upper nasal region of the Maba cranium look particularly similar to those of Neanderthals.
Remarks
Overall, the Harbin cranium shows a distinctive combination of apomorphic and plesiomorphic features. These features present a clear diagnosis, supporting the Harbin cranium as a new species of Homo, which is distinctive from other designated Middle-Late Pleistocene human taxa, such as H. sapiens, H. erectus, H. neanderthalensis, and H. heidelbergensis/rhodesiensis.
The Dali cranium was initially proposed as a subspecies of H. sapiens (H. s. daliensis) by Xinzhi Wu, but Wu abandoned the subspecies name and called the cranium “archaic H. sapiens” in his later publications.3 It was also suggested to be a subspecies of H. heidelbergensis (H. h. daliensis),4 or should be raised to the species level (H. daliensis).5 The Hualongdong cranium shows a lot of interesting similarities with the Dali cranium. Based on our morphological comparisons and the phylogenetic analyses,1 we suggest that both the Dali and Hualongdong crania should be referred to H. daliensis. The Harbin cranium, on the other hand, shows clear diagnostic features differing from the Dali and Hualongdong crania. Here, we raise a new species name for the Harbin cranium to reflect these significant differences. Given the sister-group relationship between the Harbin cranium and the Xiahe mandible,1 it is possible that both specimens belong to H. longi sp. nov. Further human fossils from the Middle Pleistocene of China and neighboring areas will test this idea.
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Post by Admin on Jun 26, 2021 20:34:24 GMT
The history of Dragon man's skull is worthy of an Indiana Jones movie. A Chinese man reportedly discovered it in 1933 in Harbin City, in Heilongjiang, China's northernmost province. However, the man (kept anonymous by his family) worked as a labor contractor for the Japanese invaders, and chose not to turn over the skull to his Japanese boss. Instead, "he buried it in an abandoned well, a traditional Chinese method of concealing treasures," the researchers wrote in the study. The skull remained there for 85 years, surviving the Japanese invasion, the civil war, the communist movement and the Cultural Revolution, the researchers said. Before the man died, he told his family, who recovered the fossil in 2018 and later donated it to the Geoscience Museum of Hebei GEO University. The research team had never seen a skull like this before. "His head was huge — containing a large brain — with a long, low shape and massive brow ridge over the eyes," Stringer said. "His face, nose and jaws were very broad, and he had big eyes. But his face was low in height, with delicate cheekbones, and it was tucked back under the braincase, as in a modern human." The scientists found slight depressions on the top of Dragon man's head that might be healed wounds, "but we have no evidence of the cause of death," Stringer said. Further analysis determined that the skull likely belonged to a male individual who died at about age 50. "Dragon man" had a huge head and a massive brow. Unique skull An analysis of the skull revealed "typical archaic human features," but also found "a mosaic combination of primitive and derived characters setting itself apart from all the other previously-named Homo species," study co-researcher Qiang Ji, a professor of paleontology of Hebei GEO University, said in a statement. When studying the skull, the researchers looked at its shape in detail, analyzing more than 600 traits, Stringer said. Then, the team "used a very powerful computer to build trees of relatedness to other [early human] fossils. After many millions of tree-building processes, we arrived at the most parsimonious trees." The results suggest that the cranium and a few other fossils from China form a third lineage of humans that lived alongside the Neanderthals and H. sapiens, Stringer said. The family tree indicated that the newly described H. longi is more closely related to H. sapiens than Neanderthals are, he added. In other words, H. longi "shared a more recent common ancestor with us than the Neanderthals did," he said. This would make Dragon man a sister species to H. sapiens, he explained. The family tree analysis revealed another bombshell: The common ancestor humans share with Neanderthals likely lived more than 1 million years ago, which is about 400,000 years earlier than scientists previously thought, the researchers said. Time and place The man who discovered the skull reportedly found it while working on Dongjiang Bridge in Harbin. To verify that claim, the researchers ran a series of geochemical analyses — they looked at X-ray fluorescence (XRF), rare Earth elements (REE), and strontium isotopes (a variation of strontium) — to investigate the skull's unique chemical makeup. The results supported the claim; Dragon man skull's chemical composition was similar with that of fossils from humans and other mammals found in the Harbin area that date from the middle Pleistocene epoch (2.5 million to 11,700 years ago) to the Holocene epoch (11,700 years ago to present). Dirt struck to the skull's nasal cavity even had matching strontium isotope compositions with a sediment core drilled near Dongjiang Bridge, the researchers found. The team also dated the skull by looking at the regional stratigraphy (rock layers), and determining the cranium likely came from the Upper Huangshan Formation, which dates to between 309,000 and 138,000 years ago. The researchers were able to narrow that time window by taking tiny samples from the skull to examine the decay rate of the radioactive element uranium, a method that revealed that the cranium is at least 146,000 years old, dating to the middle Pleistocene epoch. Given this time frame, it's possible that other human species, including H. sapiens, interacted with H. longi, the researchers said. In the middle Pleistocene, Harbin was a forested floodplain. "Like Homo sapiens, they hunted mammals and birds, and gathered fruits and vegetables, and perhaps even caught fish," study lead researcher Xijun Ni, a professor of primatology and paleoanthropology at the Chinese Academy of Sciences and Hebei GEO University, said in the statement. Based on Dragon man's large size, as well as his location in northeast China, the researchers suggested that H. longi could survive in harsh and cold environments, which helped them migrate through Asia.
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Post by Admin on Jun 26, 2021 21:18:39 GMT
Is Dragon man really a Denisovan? The study's anatomical analyses are "well done" and "impressive," but the conclusions are "too adventurous," three scientists specializing in human evolution, who were not involved with the study told Live Science. It's possible that the cranium is a Denisovan fossil, all three said. Many think the Denisovans "evolved from an ancestral form called Homo heidelbergensis/ rhodesiensis that dispersed from Africa about 600,000 years ago into Eurasia. In Europe, Homo Heidelbergensis evolved into Neanderthals and in Asia into Denisovans," Silvana Condemi, a paleoanthropologist at Aix-Marseille University in Marseille, France, told Live Science in an email. Coupled with the fact that the Denisovans are also known from Asia and that the time period that Denisovans and the Harbin skull existed overlap, it's quite possible that Dragon man is a Denisovan, she said. "I have carefully read the anatomical and phylogenetic study," Condemi said. "The published data leads me to consider this fossil as a particular fossil that could be a Denisovan." Antonio Rosas, a paleobiologist at the National Museum of Natural Sciences in Spain, agreed that the skull likely belongs to a Denisovan. He added that the authors may have given too much weight to certain evolved facial features on the skull. "These morphological features of the face may be, in fact, primitive characteristics inherited from a common ancestor," Rosas said. "As a result ... the Harbin skull could be associated either with the modern human clade or with the Neanderthal clade." (A clade includes species that share a common ancestor.) An additional 3D test, known as a geometric morphometric analysis, might shed light on the skull's identity, said Fernando Ramirez Rozzi, director of research specializing in human evolution at France's National Center for Scientific Research in Paris. This analysis lets scientists compare hundreds of traits at once and determines which traits are most important for distinguishing a new group. While there are precious few Denisovan remains known to scientists, it would be possible to compare the tooth from the Harbin skull with those attributed to Denisovans, Ramirez Rozzi added. However, the study's researchers said they did consider that the skull was a Denisovan. "I think that Harbin could certainly be a Denisovan, suggested by the very large molar with splayed roots, and the close phylogenetic relationship with the Xiahe jawbone [in northern Tibet], which could be Denisovan," Stringer said. "But until we have a complete Denisovan genome with a complete cranium (or better still, a complete skeleton!), we cannot resolve this question properly, only talk about probabilities." The three studies were published on Friday (June 25) in the journal The Innovation. www.cell.com/the-innovation/fulltext/S2666-6758(21)00056-4www.cell.com/the-innovation/fulltext/S2666-6758(21)00057-6www.cell.com/the-innovation/fulltext/S2666-6758(21)00055-2
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