Homo longi

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Homo longi
Temporal occurrence
0.309 to 0.138 million years
Locations
Systematics
Human (Hominoidea)
Apes (Hominidae)
Homininae
Hominini
homo
Homo longi
Scientific name
Homo longi
Ji , Wu , Ji , Li & Ni , 2021

Homo longi is thename proposedby Chinese paleoanthropologists in June 2021 for a fossil hominine skull that was discovered near Harbin in northeastern China , probably as early as 1933. The position of the find in the family tree of the genus Homo is controversial. While some of the Chinese researchers believe they recognize a proximity to anatomically modern humans ( Homo sapiens ), other researchers interpret the find as moreclosely relatedto the Denisova humans or cautiously name the skull asHarbin cranium ("Harbin skull").

Naming

The name of the genus Homo is derived from the Latin homo [ ˈhɔmoː ], German human. The epithet longi refers to the geographical name Long Jiang (literally: Dragon River), a regionally common name for Heilongjiang Province , in which the city of Harbin is located. Homo longi therefore means "dragon man".

discovery

The skull was allegedly discovered in 1933 by an anonymous contract worker who was working for the Japanese occupation forces at the time in the area of ​​the Japanese-established puppet state of Manchukuo on the construction of the Dongjiang Bridge over the Songhua River near Harbin. Unnoticed by the Japanese overseers - according to tradition - he discovered the skull on the riverbank one day and hid it from the Japanese, presumably because at the end of the 1920s the fossils of the Peking man had received a lot of attention from the Chinese public he was therefore convinced of the great scientific value of the find. The man hid the skull - not uncommon in China at the time - in an abandoned well. After the founding of the People's Republic of China, the man worked in agriculture and avoided everything that would have betrayed him as a former contract worker for the Japanese occupiers. Only shortly before his death did he tell his grandchildren about the skull, which was then taken from its hiding place in 2018 and made available to the Geoscientific Museum of the Hebei GEO University (河北 地质 大学 / Héběi Dìzhì Dàxué ).

Dating

The exact location of the skull is not known, which is why the geological layer from which the fossil was taken is also not directly known. There are also no animal fossils or artifacts that were recovered with the skull and that would have made it possible to date at least approximately. Even radiometric dating of the skull was made difficult by the long time lag between discovery and scientific processing. With the help of the uranium-thorium method, only a minimum age could be determined, which, according to the analyzes, is 146,000 to 150,000 years.

Alternatively, various animal fossils from the Harbin region were compared with the skull using X-ray fluorescence analysis , with the result that some of these animal fossils showed similar patterns for calcium , phosphorus , iron and manganese as the skull. From these data it could be concluded that the skull probably came from the same geological layer as these reliably documented animal fossils. Furthermore, adhesions from the nose of the skull were scanned for rare earth metals and their concentrations were also compared with the concentrations of other, reliably dated fossils. Finally, with the help of the strontium isotope analysis , a comparison of mineral buildup on the skull and the results of several drillings not far from the Dongjiang Bridge was used as a material for determining the age.

From all these indications it was reconstructed that the skull originates from the uppermost area of ​​the Upper Huangshan Formation , which with the help of optically stimulated luminescence is ascribed an age of 309,000 to 138,000 years.

Initial description

The holotype and so far the only fossil of Homo longi is a very well preserved, massive skull without a lower jaw (collection number HBSM2018-000018 [A]), the minimum age of which is 148,000 ± 2,000 years. The inner volume of the skull is around 1420 cm³, which corresponds approximately to the brain size of the anatomically modern human being as well as the brain size of the Neanderthal man . The short and flat face with small cheekbones also suggests a closeness to Homo sapiens . The elongated and flat skullcap, pronounced bulges above the eyes, the shape of the eye sockets and the only remaining tooth, a very large molar M2, are reminiscent of archaic groups of the homo genus .

Due to the nature of the bones, it was assumed that the owner of the skull was a man and was around 50 years old during his lifetime. At the same time, however, it was mentioned that the enamel of the molar was only slightly chewed, which suggests a significantly younger age. The preserved tooth sockets give reason to assume that the front teeth were also quite large.

In the first description of Homo longi , the Harbin skull is compared with other, presumably similarly ancient skull finds from China, in particular with the fossils referred to by Chinese researchers as Dali man , Jinniushan man , Xuchang man and Maba man , which differ from each other the Harbin skull, however, can be clearly distinguished. These differences are emphasized by assigning the skull to a species of its own. In a final section of the first description, headed “Notes”, it says, but without further specification of characteristics, provided the Harbin skull and the Xiahe lower jaw belong to “sister groups”, then it is possible that both fossils are of the same species ( Homo longi ) belong; the Xiahe lower jaw was identified as the remnant of a Denisova human based on DNA analysis . In a morphological analysis of the Harbin skull published parallel to the first description, however, it was identified as a sister group of Homo sapiens . In addition, the skull was consistently referred to as the Harbin skull, the species name Homo longi was not mentioned. A third report concerning the age determination of the skull did not mention the species name either.

criticism

The contradicting statements about the alleged sister groups and the speculation about a possible affiliation of Xiahe lower jaw and Harbin skull (of which there is no lower jaw, so that a comparison of the two finds is impossible) of the same type immediately met with criticism from experts. If the skull actually belongs to the Denisova man, then it could not be a sister group of Homo sapiens , the closest relative would then be the Neanderthals. However, this can only be clarified by a DNA analysis, which has not yet been carried out on the Harbin skull. The naming of a hominine species based on a single fossil is also controversial among experts today. In fact, only five of the more than a dozen scientists involved in the study of the skull, who were the authors of the first description, decided to name a new species.

The studies on the Harbin skull were originally supposed to appear in one of the renowned journals - Nature or Science . According to co-author Chris Stringer , such extensive changes to the initially presented text were requested in the peer review process that this project was abandoned. As an alternative, the studies appeared in “The Innovation”, an online journal that has only appeared since May 2020 and is published in cooperation with the Chinese Academy of Sciences . Stringer also sees such a similarity between the Harbin skull and the skull of the Dali man , which has been known since 1978 , that he would call both together - with priority for the earlier find - as Homo daliensis . Jean-Jacques Hublin, on the other hand, had already placed the Harbin skull near the Denisova people in April 2020.

See also

Web links

supporting documents

  1. ↑ a b Qiang Ji et al .: Late Middle Pleistocene Harbin cranium represents a new Homo species. In. The innovation. Online publication from June 25, 2021, doi: 10.1016 / j.xinn.2021.100132 .
  2. ↑ a b Stunning 'Dragon Man' skull may be an elusive Denisovan - or a new species of human. On: sciencemag.org from June 25, 2021.
  3. ↑ a b c Xijun Ni et al .: Massive cranium from Harbin in northeastern China establishes a new Middle Pleistocene human lineage. In: The Innovation. Online publication from June 25, 2021, doi: 10.1016 / j.xinn.2021.100130 .
  4. ↑ Supplemental Information - Massive cranium from Harbin in northeastern China establishes a new Middle Pleistocene human lineage. P. 7.
  5. ↑ a b c Qingfeng Shao et al .: Geochemical provenancing and direct dating of the Harbin archaic human cranium. In: The Innovation. Online publication from June 25, 2021, doi: 10.1016 / j.xinn.2021.100131 .
  6. ↑ Mysterious skull fossils expand human family tree - but questions remain. On: nature.com from June 25, 2021.
  7. ↑ 'Dragon man' claimed as new species of ancient human but doubts remain. On: newscientist.com from June 25, 2021.
  8. ↑ Everything new in the human family tree? On: science.orf.at from June 27, 2021.
  9. ↑ Massive human head in Chinese well forces scientists to rethink evolution. On: theguardian.com from June 25, 2021.
  10. ↑ Jean-Jacques Hublin: Denisovaner - It all started with a knuckle. On: Spektrum.de from April 15, 2020.