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Linxia Cheetah - Acinonyx kurteni - Printable Version

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Linxia Cheetah - Acinonyx kurteni - Acinonyx sp. - 01-02-2022

This thread is about a possible extinct acinonyx species which is the linxia cheetah.


RE: Linxia Cheetah - Acinonyx kurteni - Acinonyx sp. - 01-02-2022

A primitive Late Pliocene cheetah, and evolution of the cheetah lineage

Abstract
The cheetah lineage is a group of large, slender, and long-limbed cats with a distinctive skull and dental morphology, of which only the extant cheetah (Acinonyx jubatus) is present today. The lineage is characterized by having abbreviated, tall, and domed crania, and a trenchant dentition with a much reduced, posteriorly placed protocone on the upper carnassial. In this article, we report on a new discovery of a Late Pliocene specimen from China with an estimated age of ≈2.2–2.5 million years, making it one of the oldest specimens known to date. A cladistic analysis confirmed that it is the most primitive cheetah known, and it shares a number of unambiguous derived cranial traits with the Acinonyx lineage, but has more primitive dentition than previously known cheetahs, demonstrating that the many unusual skull and dental characters hitherto considered characteristic of cheetahs evolved in a gradual fashion. Isolated teeth of primitive cheetahs may not be recognizable as such, but can be confused with, for instance, those of leopards or other similar-sized pantherine cats or pumas. The age and morphology of the new specimen supports an Old World origin of the cheetah lineage, not a New World one, as has been suggested. We name the new species Acinonyx kurteni in honor of the late Björn Kurtén.

The cheetah lineage (Acinonyx sp.) is a group of large, long-limbed felids with small, domed skulls, which lived in open habitats across much of Eurasia in the Late Pliocene-Pleistocene, of which only the species Acinonyx jubatus is present today (13). Acinonyx jubatus is an unusual type of felid with a distinct craniodental and skeletal morphology, and, uniquely among felids, it is anatomically adapted for high-speed pursuit in open landscapes (37). Cheetahs are now found almost exclusively on the African grasslands and semideserts (378), but they used to be present in open-forest type habitats in Asia before being exterminated by humans (369). Cheetahs are usually rare in fossil assemblages and are most often found as isolated fragmentary specimens (21012). In the Plio-Pleistocene of North America, another lineage of cheetah-like cats (Miracinonyx sp.) was present, which also had long limbs and small, tall and abbreviated skull shapes (213).

Remains of cheetahs and cheetah-like cats are known from the Late Pliocene (early Villafranchian) to the Late Pleistocene of Africa and Eurasia (Acinonyx sp.), and North America (Miracinonyx sp.), but complete skulls are very rare and are only known for derived species such as the Late Pleistocene Miracinonyx trumani (13), and the giant Eurasian cheetah Acinonyx pardinensis from the middle-late Villafranchian (114). Although larger, the latter is morphologically very similar to the extant cheetah, and both species are derived members of the cheetah lineage, whereas more primitive members of this lineage are very poorly known, making hypotheses on the evolution of the many unusual characters in the skull, mandible and dentition tentative. In this article, we present a new discovery from the Late Pliocene of China of a new species of primitive cheetah, whose skull shows a unique combination of primitive and derived characters, and demonstrates gradual evolution of the many derived craniodental traits considered characteristic of cheetah lineage, thus shedding new light on the early evolution of the cheetah lineage. The dentition is far more primitive than in all other cheetah-like cats, raising doubts on the identification of isolated dental finds of large cats from the Pliocene-Pleistocene of Eurasia and Africa, which are often attributed to leopards.




Results

The new specimen of a primitive cheetah consists of an almost complete skull (Fig. 1) from the Late Pliocene, fossiliferous-rich “Hezheng” locality, Linxia basin, South-eastern part of Gansu Province, China (15), with an estimated age of 2.55–2.16 MYA, as indicated by paleomagnetic analysis (16). Thus, it is among the oldest known cheetahs, rivalling other finds, such as European Acinonyx pardinensis from the Late Pliocene (middle-late Villafranchian), with an estimated age of ≈2.2 MYA (11214), and North African A. aicha, with an estimated age of ≈2.5 MYA (17); furthermore, it is from China, not Europe or Africa, as are other very early finds (121018). The skull is almost complete except for the occipital condyles, basioccipital region and upper canines. It has undergone very little postmortem distortion, other than the middle and anterior parts of the nasals having been crushed slightly into the nasal cavity, and the dorsal part of the skull having been distorted very slightly to the right hand side. Unlike A. pardinensis, the new specimen is no larger than crania of extant cheetahs (Table 1).

Significantly, an unusual combination of characters, hitherto unknown in cheetah-like cats, indicates a basal position for this specimen within the Eurasian-African cheetah lineage. Numerous unambiguous synapomorphies identify this skull as a cheetah-like cat (Fig. 2), and at least three unambiguous synapomorphies identify the current specimen as belonging to the lineage of the true cheetahs (Acinonyx sp.): a very wide braincase relative to skull length; enlarged frontal sinuses; and a large P3 parastyle. It also has a well developed P4 ectoparastyle, as in other Acinonyx sp., in particular A. jubatus, but this is a slightly more variable character. As in other Acinonyx sp., the enlarged P4 is situated such that its aboral edge is markedly anterior to the aboral rim of the orbital aperture, which may or may not have evolved convergently in M. trumani, because of its absence in M. inexpectatus. Although the canines are not preserved, the alveoli and root size indicates a small upper canine, similar to those of other Acinonyx sp. and M. trumani. The postcanine dentition is surprisingly primitive for a cheetah.
Upper premolar teeth of cheetahs are instantly recognizable from those of all other Eurasian-African felines from the Pliocene-Pleistocene, owing to several unique apomorphies (Figs. 2 and 3). A highly diagnostic feature of all cheetah-like cats is the reduction of the P4 protocone and frequent absence of a protocone cusp, culminating in the extant cheetah, where it is often little more than a lingual bulge. Protocone position distinguishes Miracinonyx sp. from most Acinonyx sp., because in Miracinonyx sp. it is situated at the normal position for felids, medial to the parastyle or parastyle/paracone junction, whereas in Acinonyx sp. it is situated posteriorly to the parastyle/paracone junction (Fig. 3 D and E). Upper premolars in cheetahs are also more slender and blade-like than in other large felids. This unique and easily identifiable P4 character combination is ubiquitously used to identify isolated carnassials as belonging to Acinonyx sp. in the Eurasian and African Pliocene-Pleistocene. The new Chinese cheetah demonstrates that the unusual cheetah-like skull morphology precedes the development of the highly sectorial P4, because it has a prominent, aborally situated and cusped P4 protocone (Fig. 3F), like other felines (Fig. 3 A–C), and the shape of P4 is also typical of that of other felines in being heavy relative to length, rather than slender, as is typical of Acinonyx sp. The Late Pliocene Acinonyx aicha also has a more primitive, aborally situated P4 protocone (17), although it is distinctly more reduced than in the Chinese cheetah, indicating that reduction of protocone size and its posterior shift were two separate events in cheetah evolution.

Bivariate and multivariate analyses on 33 linear metric variables corroborate the unusual combination of craniodental traits in the new Chinese cheetah, which shows a clear tendency in cranial morphology to modern African cheetahs (A. jubatus), although there are also distinct differences between the two species; the morphology of the P3 and P4 in the Chinese cheetah, however, are far more characteristic of pumas or leopards (see SI Appendix). The unique combination of primitive and derived traits collectively identify the new Pliocene Chinese find as the most primitive cheetah known to date, and demonstrates gradual evolution of the many derived traits characteristic of later species. We name it Acinonyx kurteni in honor of the world renowned Finnish paleontologist Björn Olof Lennartson Kurtén (1924–1988), in commemoration of his great contribution to carnivore paleontology. Evidently, in the Late Pliocene, several morphological grades of cheetah evolution were present in Eurasia and Africa, because most hitherto-known African and European finds, for instance of A. pardinensis and finds attributed to the extant cheetah, appear virtually modern in craniodental morphology, whereas A. aicha and in particular A. kurteni represent more primitive forms.
A. kurteni may be identified by the following unique combination of characters: Late Pliocene cheetah with a cranium of comparable size to the extant cheetah (Acinonyx jubatus); skull shape very tall and abbreviated with domed and lateromedially very wide braincase; frontal sinuses distinctly enlarged and nasal aperture large; occipital crest strongly developed and occipital area distinctly more posteriorly inclined than in other Acinonyx sp.; frontal and jugal postorbital processes moderately developed; posterior edge of maxilla broadly rounded; frontals gently concave around middle; posterior temporal bar to occipital crest very short; snout rectangular, not tapering in dorsal or ventral view; zygomatic arch dorsoventrally taller than in A. jubatus; moderately developed postglenoid process and weakly developed preglenoid process; nasals posteriorly wide; single infraorbital foramen; incisors small and based on alveolar dimensions, C1 appears to have been of moderate size with an oval cross-section; entire P3 anterior to infraorbital foramen; P3 sectorial with large parastyle; large, wide and nonsectorial P4 with large, cusped and anteriorly placed protocone; anterior edge of P4 anterior to infraorbital aperture and far anterior to orbital aperture; P4 ectoparastyle well developed.
Upper premolar morphology in A. kurteni deviates significantly from those of extant cheetahs and bears a much closer resemblance to those of other large cats (Pantherinae and the puma; see SI Appendix). Had such carnassials been found isolated, as is the case for most fossil finds, it is doubtful that they would have been recognized as belonging to a cheetah; more likely, they would have been attributed to leopards or other similar-sized pantherine cats. This indicates that at least some of the many fragmentary finds from the Eurasian-African Pliocene-Pleistocene identified as medium-sized pantherine cats, for instance leopards, could belong to primitive cheetahs instead (see also ref. 18 for discussion of possible chimera specimens of cheetahs and leopards), and that primitive cheetahs may not be as rare in faunal assemblages as traditionally believed, although this remains to be verified. It also raises concerns on biogeographical, ecological, and faunistic hypotheses based on fragmentary material, because of the potential for misidentification of early members of phyletic lineages, which have yet to evolve the derived dental characters characteristic of later members of such lineages. Owing to the cheetah lineage being highly adapted for high-speed pursuit in open territory, the presence of cheetahs in Pliocene-Pleistocene deposits has often been used to infer an open-type habitat with shrub and grassland, whereas the presence of leopards is indicative of more wooded habitats (1361923). In accordance with the above, it has recently been suggested that some purported discoveries of leopards may instead be of primitive pumas (24), which casts doubts on evolutionary and biogeographical hypotheses of pantherine and puma lineage distribution.
Owing to its unusual morphology, inferences of relationships of the extant cheetah have been murky, and traditionally, it has been assigned to its own subfamily, the Acinonychinae (25). Modern analyses have all favored a close relationship with the puma within a larger group of small felid species (2628). The relationship of the Eurasian-African Acinonyx lineage and the American Miracinonyx lineage has been a subject of debate, with morphological data favoring a relationship of the two, albeit not necessarily a close one, with the early puma, Puma pardoides (also known as Panthera schaubi) (2429) as a possible common ancestor; and molecular data favoring two separate lineages (27), implying great convergence of many craniodental and postcranial traits. The results of the current study indicate a close relationship of the two lineages and that P. pardoides may be a possible ancestor of both but also demonstrate that the late Rancholabrean (Wisconsian) M. trumani was much more craniodentally derived and cheetah-like and shares a large number of craniodental synapomorphies with Acinonyx sp., which are not present in M. inexpectatus. The fossil record of the extant puma (Puma concolor) in the USA is only ≈400 KYA (213031), and thus, the inference that Miracinonyx sp. and the puma shared a last common ancestor in the Americas in the mid-late Pliocene (2728) is not supported by paleontological evidence. The presence of primitive pumas, such as P. pardoides, in the Eurasian Late Pliocene favors a Eurasian-African origin of the Puma–Miracinony–Acinonyx group (24), with separate dispersals of the former two into the Americas, perhaps twice in Miracinonyx, as discussed by ref. 31. The above is supported by the unusual combination of primitive and derived characters in A. kurteni, and, accordingly, a New World origin of cheetahs (as suggested in refs. 28 and 32) appears unlikely. Although our analysis of craniodental characters favors one evolutionary lineage of cheetah-like cats, and indicates a close relationship of Miracinonyx, at least M. trumani, to AcinonyxA. kurteni has a number of primitive traits, notably more primitive dentition, that could indicate two separate lineages, each culminating in craniodentally highly derived predators, and thus, we would not at this time entirely rule out that the highly cheetah-like morphology of M. trumani evolved convergently in the Americas, as suggested by ref. 27.


Materials and Methods

Characters of the skull and mandible were scored in two species of extant felids [puma (n = 23) and cheetah (n = 12)] and 4 species of extinct cheetahs and cheetah-like felids, using the extant ocelot (n = 11) as outgroup. All morphometric characters were found by statistical (MANOVA, post hoc Tukey HSD) tests on angular transformed morphometric ratios, to restore normality to the variables (33), and character states were accepted as dissimilar only at P < 0.001 and with either no overlap (discrete) or overlap only on extreme outlier specimens (<5% of sampled population). Phylogenetic analysis (heuristic search) and bootstrap analysis (1,000 replications) were performed in Phylip ver. 3.6 (3435). We also conducted a variety of bivariate and multivariate statistical analysis, comparing the proportions of A. kurteni to the extant cheetah, puma, and pantherine felids (clouded leopard, jaguar, lion, leopard, tiger, snow leopard) (see SI Appendix). Institutional abbreviations used in Fig. 3 are as follows: BM, Natural History Museum, London; CN, Zoological Museum, Copenhagen; NRM, Naturhistoriska riksmuseet, Stockholm; MNHN, Museum National d'Histoire Naturelle, Paris; SHNM, Shanghai Science and Technology Museum.


Skull of the specimen

*This image is copyright of its original author


*This image is copyright of its original author





RE: Linxia Cheetah - Acinonyx kurteni - Acinonyx sp. - 01-02-2022

Retraction for Christiansen and Mazák, A primitive Late Pliocene cheetah, and evolution of the cheetah lineage

EVOLUTION Retraction for “A primitive Late Pliocene cheetah, and evolution of the cheetah lineage,” by Per Christiansen and Ji H. Mazák, which appeared in issue 2, January 13, 2009, of Proc Natl Acad Sci USA (106:512–515; first published December 29, 2008; 10.1073/pnas.0810435106).

The undersigned author wishes to note the following: “After further examination, it was determined that the fossil used in the study was a composite specimen from the late Miocene laterite and not from the early Pleistocene loess. The article is hereby retracted.”
Ji H. Mazák


RE: Linxia Cheetah - Acinonyx kurteni - Acinonyx sp. - 01-02-2022

Chinese Paleontologists Raise Doubts About a Cheetah Fossil in Science

In a 24 December 2010 News Focus story in Science, Dr. DENG Tao,  Institute of Vertebrate Paleontology and Paleoanthropology, Chinese Academy of Sciences (IVPP), presented a query for a 2009 PNAS paper by Per Christiansen of the Zoological Museum in Copenhagen and Ji H. Mazák of the Shanghai Science and Technology Museum. Christiansen and Mazák reported a new species of the cheetah (Acinonyx kurteni) from the Late Pliocene loess deposits of the Linxia Basin in Gansu Province, China. As a vertebrate paleontologist who specialized on the Late Cenozoic mammals of the Linxia Basin for many years, DENG naturally had particular interests in reading this paper. Having carefully checked the described skull in this paper’s figures, unfortunately, he found that Christiansen and Mazák studied a fossil forgery, the sole foundation of the paper. In a March 4, 2011 letter in Science, Mazák and Christiansen note “the occipital area and zygomatic arches have been heavily restored in plaster, probably to make it appear more complete, thus enhancing its commercial value, a common malpractice among Chinese fossil dealers.” DENG and his colleague responded, also in Science, that they are pleased to see this note, but stand by their view that the skull is a composite with fabricated features.
In the beginning of 2009 in National Geographic News, DENG pointed out the problems in this PNAS paper. DENG was “astonished” to read the new study. The newly identified skull is not from a new species, he said. DENG explained his team had already described this species as Sivapanthera linxiaensis. DENG said Sivapanthera is the fossil genus of the ancient cheetah. Today’s cheetahs belong to the Acinonyx genus. As Christiansen and Mazák admitted, teeth are highly diagnostic for identification of the cheetah in general, and for the establishment of their new species in particular. A straightforward comparison shows that the morphology and measurements of the cheek teeth of the new skull fall within the variation ranges of S. linxiaensis. Revealingly, Christiansen and Mazák cited the monograph of QIU and his colleagues as the basis of their geologic age determination, but did not mention anywhere in their paper about the previously established species, not to mention any direct comparison of the two forms. DENG also said that the skull in the new study was not an intact original, but rather a compilation from bones of various individuals and possibly even various species. The difference between an intact skull and a compilation is apparent from comparisons of the photos of the skull in the current study and the skulls his team studied, DENG said. In order to confirm these observations, DENG requested an examination to the skull in person, but Mazák declined to grant him access to the specimen.
Despite being unable to examine the new specimen, DENG said, the forged parts of this skull are easily recognized from the figures of their paper. In lateral view of the skull, it clearly shows that the zygomatic arch is not only unnaturally high and robust, without postorbital process, which is usually prominent and pointed in the cheetah, but also has clear boundaries where the “zygomatic” was artificially pieced together with the skull. Furthermore, the zygomatic arch does not belong to the skull, and it may not be a zygomatic arch of a carnivore at all. The occipital part is obviously not original, and it is undoubtedly artificial for several reasons. The direction of the occipital surface is so abnormal that it becomes almost horizontally oriented and its lowest point connects directly with the posterior end of the zygomatic arch. In so doing, there is no space left at all for the tympanic bullae, the mastoid and paroccipital processes, and the occipital condyles. In dorsal view of the skull, the parietal area was glued together with some bone pieces to imitate the skull of a modern cheetah, but the forger did not make the parietal crests, and in doing so giving away the nature of the forgery. The braincase, with a sagittal crest, was made of plaster and painted also to imitate the skull of the modern cheetah. Some large rounded plaster spots and unpainted areas on the parietal and occipital parts are very marked, which indicate that the braincase is a plaster cast. Many traces of daubing plaster can be easily observed in the posterior part of the skull. In ventral view of the skull, the whole basioccipital area is filled and daubed with plaster; because this area is so complicated that the forger could not replicate the morphology seen in the modern cheetah. As a result, no anatomical structures can be found in this area.
Frequent contacts with the local “dragon-bone” dealers during DENG’s work in the Linxia area gave him knowledge that it is quite common to come across such forgery, especially in recent years. Personally, DENG has seen hundreds of seemingly “complete” skulls of various kinds, and he knows well that unqualified collectors are often cheated by being sold forgeries. Unfortunately, Mazák was one of them.
Christiansen and Mazák alleged that the skull specimen was from the ‘‘Hezheng’’ locality, with an estimated age of ~2.2-2.5 million years. In fact, Hezheng is not a locality, but a county of Linxia Prefecture, where no fossil mammals have ever been found from loess deposits so far as DENG knows. A “fossiliferous-rich locality” does exist, but it is Longdan in Dongxiang County of Linxia Prefecture. A monograph on the Longdan fauna was already published by QIU and his colleagues in 2004, wherein the new cheetah species, Sivapanthera linxiaensis, was described, based on two skulls with their articulated lower jaws and other isolated skull or lower jaw specimens. Without further details to be gleamed from personal examination of the specimen in question, DENG can only conclude that, at a minimum, Christiansen and Mazák completely failed to do due diligence to establish a new species at multiple levels: failing to recognize a fake specimen; failing to work on an actual specimen, because the senior author, Christiansen, relied on photos to describe a new species, as Mazák said; failing to explore and verify a fossil locality; failing to inspect primary literature; and failing to acknowledge an existing taxon.

To sum up, the conclusion of Christiansen and Mazák is based on a fossil forgery, so it is extremely unfounded and groundless. DENG wrote to PNAS on 16 January 2009 and strongly urged the authors or the journal to retract this paper. In a 4 February 2009 letter to DENG, PNAS stated that his observations do not suggest “he examined the skull in person”. DENG said he has not pursued the matter further because Mazák has declined to give him access to the skull.
Now Mazák and Christiansen argue that DENG’s inquiries “were presented without tangible evidence” and “they were based not on personal study of the specimen but on a few images in our study”. But as mentioned above, DENG had asked for an opportunity to examine the skull in person, only to have Mazák decline his request. Adding to this irony, according to Mazák, Christiansen, the senior author, had composed the paper without having seen the original specimen, and only based his descriptions on photos of the specimen. Unfortunately, Mazák and Christiansen insist that this altered skull does not impinge on Acinonyx kurteni’s status as a primitive cheetah. DENG indicates that the occipital area and zygomatic arches have not only been described in their original paper, but also in their phylogenetic and principal components analyses. DENG also emphasizes that the authors committed grave errors, which did serious harm to the field of vertebrate paleontology and damaged the credibility of PNAS.


*This image is copyright of its original author

Fig.1: Fabricated features in Holotype of A. kurteni, n.sp. SHNM8.1.07 (Shanghai Science and Technology Museum; People's Republic of China) in lateral (A); dorsal (B);and ventral © views.(Marked by DENG Tao from PNAS)


*This image is copyright of its original author

Fig.2: Skull and lower jaw of the cheetah Sivapanthera linxiaensis (Scale bars = 5 cm) (Image by DENG Tao)


*This image is copyright of its original author

Fig.3: Two cheetahs of Sivapanthera linxiaensis are hunting a bovid of Leptobos brevicornis (Illustrated by Li Rongshan)


RE: Linxia Cheetah - Acinonyx kurteni - Acinonyx sp. - 01-02-2022

Reconstruction of Acinonyx kurteni (species does not exist but was thought to exist)


*This image is copyright of its original author



RE: Linxia Cheetah - Acinonyx kurteni - Acinonyx sp. - 01-02-2022

5 Greatest Palaeontology Fakes Of All Time #5: The Linxia Cheetah

In a piece by Richard Stone in this week’s Science, it was pointed out that in Chinese Museums, it is likely that up to 80% of the marine reptiles on display have been altered or artificially combined to some degree. This seems like a shocking figure, but it is more understandable when it is considered that few of these museums have palaeontologists as staff, and that many of these fossils are unearthed by Chinese farmers that dress their finds up so that a museum is more likely to buy them. Of late there has been a boom, both in the numbers of museums, but also in the acquisition funds set aside for accessioning fossils; this, coupled with prizes for the best specimens, means that finding (or fabricating) a complete fossil can prove to be quite lucrative. This forgery can range from the odd added-in bone here and there, to the whole scale chimeric sticking together of many specimens.


In many cases, these fakes are blatantly obvious. The centerpiece of the Geological Museum of China’s Prehistoric Life exhibit (seen below) is of a striking Triassic ichthyosaur. But when you take a closer look, something is amiss. In the upper part of the specimen, the shoulder girdle and lower jaw can clearly be seen, representing the ventral (belly) side of an organism, whereas lower down, the dorsal (back) surface of the vertebrae are seen; clearly this is several specimens botched together. Chinese museums are riddled with examples such as these, which is a real pain for any researcher in that they have to spend many days separating the real fossil "wheat" from the faked "chaff" -- not to mention the untold damage that has been done to the now palaeontologically defunct specimens.

The commercial fossil market is awash with fakes; in fact it can be rather difficult to buy real fossils. Forgers in China have faked pretty much any fossil you like; examples include birds, fish, mammals, dinosaurs, dinosaur eggs, icthyosaurs, and other reptiles - they have a particular penchant for mimicking the sauropterygian Keichosaurus. Although the bulk of faked fossils come from China, this problem is not limited to China. Many of those famous Morrocan trilobites are faked, as are Pleistocene mammal skulls from around the world. Indeed, for anybody that thinks they have ever bought any fossilized amber: unless it came from the Dominican republic it is almost certainly fake. (PaleoDirect have a great emporium of faked fossils at their website.)


Most of these fossils are prepared well enough to fool your average fossil dealer or even museum worker, but can easily be earmarked by a trained palaeontologist. However, occasionally – just occasionally – a hoax fossil slips through the net, and ends up in the scientific literature. These fossils tend to whip up a maelstrom of debate and can incite fierce opinion on both sides, ending up with red faces for many of those involved when they are later revealed to be hoaxes. Thankfully it doesn’t happen very often, but over the next few weeks I'm going to pick up on some of the greats.

5. Acinonyx kurteni - the Linxia Cheetah
Acinonyx kurteni was named for a skull found in Late Pliocene deposits and, at 2.5-2 Ma, this makes it one of the oldest cheetahs ever found. First described by

Per Christiansen and Ji H. Mazák early in 2009 in the prestigious journal PNAS, it was excitedly described as the most primitive cheetah ever found, having a unique combination of both primitive and derived traits. The authors went as far to state that this specimen disproves that cheetahs originated in the New World, favouring an Old World origin based on the interpretation of this fossil.

Alas, it was too good to be true. As soon as 
Deng Tao, a paleontologist at the Institute of Vertebrate Paleontology and Paleoanthropology in China saw the paper, he knew it was fake. Just from from the published pictures, he said that he could see that parts of the skull have been concocted from plaster, (I can't see this myself, but I'll take his word for it). But for Deng, what really gave the game away was a subtle aspect of the morphology; as he explains, “The parietal area is glued by some bone pieces to imitate the skull of a modern cheetah, but the forger did not make the parietal crests".

As yet, PNAS have refused to retract the paper and the authors still stand by their interpretation. They have refused requests to view the skull and have not answered as to where the fossil was sourced from. This is downright dodgy to me, and so I'm inclined to agree with Deng, who has collected from Linxia for over a decade and knows the suspicious characters that prowl the area, and whose opinion is corroborated by 
Qiu Zhanxiang, a world expert on mammalian skulls.

This fossil makes my list because when it was published it made quite a storm, being published as it was in PNAS, and very quickly was covered in many newspapers. In these modern times, an idea can be cemented in the public consciousness very quickly, regardless of whether it is subsequently retracted or not. Even if this paper had been retracted a month or so later I doubt that it would have been noticed; we can compare this with some of the examples later on in this series. Deng has now decided not to pursue the matter in any case, as he has not been allowed to see the skull itself that lead to the ruckus.

In a way, though, retraction is not tackling the root cause of what lead to this paper being published. There needs to be an extensive training program for fossil preparators, and extensive guidance for those going into the field to collect. Only by nipping this problem in the bud can we prevent a legion of duplicitous dealers ruining China's 
globally important paleontological legacy, and allow us to treat fossils sourced from China with the confidence and awe that they deserve.

Next week: 
The 5 Greatest Palaeontology Fakes of All Time #4: Irritator

------
Citations and links




    Stone, R. “Altering the Past: China's Faked Fossils Problem.” Science 330, no. 6012 (2010): 1740.

    Christiansen, P., and J. H Mazák. “A primitive Late Pliocene cheetah, and evolution of the cheetah lineage.” Proceedings of the National Academy of Sciences 106, no. 2 (2009): 512.

The Cheetah story was also picked up by many news outlets,
    The Guardian http://www.guardian.co.uk/science/2008/dec/29/fossil-cheetah-skull-evolution
    National Geographic http://news.nationalgeographic.com/news/2008/12/081229-cheetah-skull.html
    Live Science http://www.livescience.com/animals/081230-cheetah-skull.html

Also, see PaleoDirect's fake fossil page at http://www.paleodirect.com/fakefossils1.htm for an incredible collection of fakes and how to tell the difference.




RE: Linxia Cheetah - Acinonyx kurteni - Acinonyx sp. - 01-02-2022

The conclusion of the validity of kurteni:

In Chinese museums fossils are and in China in general fossils are faked. All kinds of fossils have been faked including fossils of mammals, birds, marine reptiles, terrestrial reptiles etc. The fossil of the linxia cheetah could also be fake according to Chinese paleontologist Deng Tao. He suggests that the fossil is fake because the skull looks concocted by plaster. When this was reported to PNAS (a place for publishing papers), the staff of PNAS did not bother to look at and examine the skull; this is remarked to be dodgy. Dr.Qiu Zhan Jiang (an expert at mammal skulls) agrees with Deng Tao. Deng also argues that this specimen is not a new species but it is Sivapanthera linxiaensis (which was later found to be Acinonyx pardinensis linxiaensis but this is debatble). Mazak and Christiansen, the authors of said study insist that the plasters don’t take away the status of kurteni as a primitive cheetah but Christiansen has not even seen the skull in person. Only Mazak has seen the skull in-person and he also refuses to let Deng see it in-person.  Finally, Dr.Mazak withdrew the paper, admitting that the linxia cheetah was fake.