Graecopithecus

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Graecopithecus
Temporal range: Late Miocene
Holotype jaw and premolar
Holotype jaw and premolar
Scientific classification Edit this classification
Domain: Eukaryota
Kingdom: Animalia
Phylum: Chordata
Class: Mammalia
Order: Primates
Suborder: Haplorhini
Infraorder: Simiiformes
Family: Hominidae
Genus: Graecopithecus
von Koenigswald, 1972
Species:
G. freybergi
Binomial name
Graecopithecus freybergi
von Koenigswald, 1972[1]

Graecopithecus is an extinct genus of hominid that lived in southeast Europe during the late Miocene around 7.2 million years ago. Originally identified by a single lower jaw bone bearing teeth found in Pyrgos Vasilissis, Athens, Greece, in 1944,[1] other teeth were discovered from Azmaka quarry in Bulgaria in 2012.[2] With only little and badly preserved materials to reveal its nature, it is considered as "the most poorly known European Miocene hominoids."[3] The creature was popularly nicknamed 'El Graeco' (word play on the Greek-Spanish painter El Greco) by scientists.[4]

In 2017, an international team of palaeontologists led by Madelaine Böhme of the Eberhard-Karls-University Tübingen, Germany, published a detailed analysis of the teeth and age of the specimens, and came to the conclusion that it could be the oldest hominin, meaning that it could be the oldest direct ancestors of humans after splitting from that of the chimpanzees.[5] Their simultaneous study also claimed that contrary to the generally accepted evidence of the African origin of the hominin lineage, the ancestors of humans originated from the main ape ancestry in the Mediterranean region (before migrating into Africa where they evolved into the ancestors of Homo species).[6][4] They named the origin of human theory as the "North Side Story."[7]

These claims have been disputed by other scientists.[8] Rick Potts and Bernard Wood argued that the evidence is too flimsy to even say it is a hominin.[7] Tim D. White commented that the claim was only to support a biased argument that Africa is not the birthplace of humans; while Sergio Almécija stated that single characters such as teeth cannot tell the claimed evolutionary details.[8]

Discovery

The original Graecopithecus specimen was a single lower jaw bone (mandible) found from a site called Pyrgos Vassilissis, northwest of Athens,[9][10] in southern Greece in 1944, "reportedly unearthed as the occupying German forces were building a wartime bunker".[8] The jaw bone was almost complete with teeth when it was sent to Berlin for analysis, but was damaged by bombings during the final phases of World War II. Only the second molar and fourth premolar remain intact, while fragments of other teeth are still embedded.[11] The original finder, German paleontologist Bruno von Freyberg initially believed that it belonged to an extinct Old World monkey Mesopithecus, as he reported in 1951.[12][13] However, Gustav Heinrich Ralph von Koenigswald realised that it was the tooth of an ape family and erected the scientific name Graecopithecus freybergi in 1972, after the discoverer.[1][5]

Another tooth remain was discovered from Azmaka quarry in Bulgaria in 2012.[2]

Description

Graecopithecus tooth (Azmaka, Bulgaria.[2])

The mandible of Graecopithecus with a third molar that is very worn, the root of a second molar, and a fragment of a premolar, is dated from the late Miocene around 7.2 million years old.[5] Excavation of the site is not possible (as of 1986) due to the owner having built a swimming pool on the location.[10]

The thick enamel and large molars are the features that convinced von Koenigswald that the specimen belonged to a hominid species.[14] X-ray microtomography and 3-dimensional reconstruction in 2017 revealed that it belonged to an adult individual and possibly a male. The partial fusion of the fourth premolar (P4) roots is an additional evidence that it is of a hominid, and the thick enamel resembles those of the human lineage (hominins).[5]

Classification

G. freybergi is considered to be possibly the same taxon as Ouranopithecus macedoniensis,[15][16] another extinct hominid described in 1977 from northern Greece.[17] Due to paucity of specimens and poor quality of the fossils, it remains the least well known extinct hominid found within Europe.[3] In 1984, British palaeontologists Peter Andrews and Lawrence B. Martin classified Graecopithecus and Ouranopithecus as synonyms (same taxon) and treated them as members of the genus Sivapithecus.[14] This classification persisted for several years until additional Ouranopithecus fossils were discovered[18] including part of the skull in the 1990s[19] that indicated better distinction as different hominids. Based on new evidences, in 1997, Australian palaeontologist David W. Cameron proposed renaming and inclusion of Ouranopithecus into Graecopithecus based on taxonomic priority with Graecopithecus macedoniensis as a new name for O. macedoniensis.[20][21] However, better O. macedoniensis specimens were found[22] including a new species Ouranopithecus turkae from Turkey[23] that supported separation of the genus. This change was generally adopted.[5][24][25][26]

Re-examination and reinterpretation

In 2017, an international team of palaeontologists led by Madelaine Böhme (Eberhard-Karls-University Tübingen, Germany) published detailed reanalysis and new interpretation in the journal PLOS One. One paper deals with an examination of the detailed morphology of molar teeth of G. freybergi from Greece and Bulgaria, and compared it with that of Ouranopithecus.[5] The study concluded that Graecopithecus was a hominin, sharing ancestry with Homo but not with the chimpanzees (Pan), and distinct from Ouranopithecus, which has more ape-like traits.[8][27] If this classification is correct, Graecopithecus would be the oldest known representative of the human lineage after the human-chimpanzee split, in 19th-century terminology, the "missing link" between human and non-human primates. The species was found to be some two hundred thousand years older than the oldest known hominid found in Africa (not necessarily ancestral to the human lineage), Sahelanthropus tchadensis.[8] The study concludes:

[The] dental root attributes of Graecopithecus suggest hominin affinities, such that its hominin status cannot be excluded. If this status is confirmed by additional fossil evidence, Graecopithecus would be the oldest known hominin and the oldest known crown hominine, as the evidence for the gorillin status of Chororapithecus is much weaker than the hominin status of Graecopithecus. More fossils are needed but at this point it seems likely that the Eastern Mediterranean needs to be considered as just as likely a place of hominine diversification and hominin origins as tropical Africa.[5]

An accompanying paper presents the study of the geological environments of the areas where the fossils were discovered. Until then, the precise date of Graecopithecus has not been resolved and usually inferred from geological data of materials related the fossils and surrounding areas that add to uncertainty in its evolutionary importance and relationship with other hominids.[10][15] It is often broadly described as 6.6 to 8 million years old.[3] The PLOS One paper resolved that the hominid lived 7.37 to 7.11 million years ago, with the specime from Greece dated to 7.18 Ma and that from Bulgaria to 7.24 Ma. It also indicates that as the species lived in Europe, it suggest "that major splits in the hominid family occurred outside Africa."[6]

It has also been proposed the Graecopithecus may not be a direct ancestor of the human lineage, but instead may have evolved its hominin-like traits independently.[28] The emergence of Homo itself is dated to close to 4 million years later than Graecopithecus, so that the appearance of Graecopithecus in Europe does not preclude the development of Homo proper in East Africa (as suggested by Homo habilis being found in Tanzania); however, the popular press reporting on the 2017 study did cast its result in terms of determining the "birthplace of mankind".[4] Graecopithecus lived in southeast Europe 7.2 million years ago, and if the premise of the study is correct, Graecopithecus, after evolving in Europe, would have migrated to Africa about 7 million years ago where its descendants would eventually evolve into the genus Homo.[28]

Criticism

The 2017 PLOS One papers made two critical conclusions: that Graecopithecus is a hominin suggesting it as the oldest ancestor of humans after splitting from chimpazees, and that as Graecopithecus is a human ancestor, Europe is the birthplace of hominins.[29] This directly challenges the prevailing knowledge that humans originated in East Africa.[4]

David R. Begun of the University of Toronto, Canada, one of the co-authors, was quoted as saying that "[t]his dating allows us to move the human-chimpanzee split into the Mediterranean area." This was set against a quote by an uninvolved anthropologist saying that "[i]t is possible that the human lineage originated in Europe, but very substantial fossil evidence places the origin in Africa [...] I would be hesitant about using a single character from an isolated fossil to set against the evidence from Africa."[4] Since 1994, Begun had adhered to a hypothesis that African hominids (including living apes) descended from Eurasian apes since the older ape fossils are found in Europa and Asia.[30][31] This is a feasible explanation as it is possible that the African ape ancestors could move to Africa around 9 million years ago from Europe.[32]

However, claiming that Graecopithecus is an evidence of human origin in Europe is illogical since all human ancestral species known so far are strictly found in Africa; as Rick Potts, head of the Smithsonian’s Human Origins Program, remarked: "I think the principal claim of the main paper goes well beyond the evidence in hand... A hominin or even a hominine (modern African ape) ancestor located in a fairly isolated place in southern Europe doesn’t make much sense geographically as the ancestor of modern African apes, or particular the oldest ancestor of African hominins."[7] David Alba at the Catalan Institute of Palaeontology in Barcelona was the first to point out that "It is not surprising at all that Begun is now arguing that hominins as well originated in Europe."[8] Julien Benoit of the University of the Witwatersrand, Johannesburg, South Africa, also commented: "Any study that counters this consensus (Out of Africa theory) would have to provide very strong evidence and perfect methodology to support its claim. In my opinion, this article doesn't meet those criteria."[33]

Other scientists have also expressed skepticism of Begun's classification. Bernard Wood at George Washington University described the hypothesis as "relatively weak" and Sergio Almécija, also at George Washington University, says it is important to bear in mind that primates seem particularly prone to evolving similar features independently. "Single characters are not reliable to make big evolutionary [claims]." Tim White at the University of California, Berkeley, asserted that the study was merely an attempt "to resurrect Begun’s tired argument with a long-known crappy fossil, newly scanned."[8]

Reassessment

In late 2017, Julien Benoit and Francis J. Thackeray re-analysed the claims of the PLOS One papers and found key issues in the major conclusions:[34]

  1. The partial fusion of the fourth premolar (P4) roots does not define Graecopithecus as a hominin since the feature is common in hominids,[35][36] even in the chimpanzees.[37][38]
  2. Thick enamel and relatively large molar teeth are not exclusive to hominins as they are also present in other Miocene apes and gorillas.[39][40]
  3. The claim that Graecopithecus is the ancestral ape of human lineage and that humans originate in Europe is not justified. Even if Graecopithecus is the basal (root ancestor) ape, all other human ancestral species starting from Sahelanthropus were in Africa, thus, still making Africa as the birthplace of humans.[34]

The study concludes:

[We] recognise a small signal for placing Graecopithecus at the root of the Hominini clade. This means that the phylogenetic relationship between Graecopithecus and Hominini is as yet not confirmed. Our analysis supports the view that Graecopithecus is potentially an important taxon for the origin of Hominini, but this is not certain and deserves further investigation and more material.[34]

Response

In 2018, Fuss, Spassov, Böhme, and Begun published a response to Benoit and Thackeray,[41] claiming that their original publication had been misrepresented and misconstrued. They explained that the conclusion of the 2017 paper had not been that Graecopithecus was certainly a hominin, but that its status as a hominin could not be ruled out, and that more research and evidence would be needed to make a conclusion[5]—a conclusion that Benoit and Thackeray make in their own paper.[34] They argueds againts Benoit and Thackeray write that they did not judge canine root derivation of Graecopithecus and Salehanthropus against each other, stating that the differences between them were within the range of sexual variation. Additionally, when Benoit and Thackeray claim that the characteristics mentioned in the 2017 paper are not unique to Hominini, they do not mention that the 2017 paper discusses canine root size and premolar root complexity reduction, which could be indications of Hominini.[41]

See also

References

  1. ^ a b c von Koenigswald, G.H.R (1972). "Ein Unterkiefer eines fossilen Hominoiden aus dem Unterpliozän Griechenlands". Proceedings of the Koninklijke Nederlandse Akademie van Wetenschappen Series B. 75 (5): 385–394.
  2. ^ a b c Spassov, N.; Geraads, D.; Hristova, L.; Markov, G. N.; Merceron, G.; Tzankov, T.; Stoyanov, K.; Böhme, M.; Dimitrova, A. (2012). "A hominid tooth from Bulgaria: the last pre-human hominid of continental Europe". Journal of Human Evolution. 62 (1): 138–145. doi:10.1016/j.jhevol.2011.10.008. PMID 22153571.
  3. ^ a b c Begun, David R. (2002). "European Hominoids". In Hartwig, Walter Carl (ed.). The Primate Fossil Record. Cambridge: Cambridge University Press. pp. 339–368. Bibcode:2002prfr.book.....H. ISBN 0-521-66315-6. OCLC 47254191.
  4. ^ a b c d e Knapton, Sarah (22 May 2017). "Europe was the birthplace of mankind, not Africa, scientists find". The Telegraph. Retrieved 20 February 2019 – via www.telegraph.co.uk.
  5. ^ a b c d e f g h Fuss, Jochen; Spassov, Nikolai; Begun, David R.; Böhme, Madelaine (2017). "Potential hominin affinities of Graecopithecus from the Late Miocene of Europe". PLOS ONE. 12 (5): e0177127. Bibcode:2017PLoSO..1277127F. doi:10.1371/journal.pone.0177127. PMC 5439669. PMID 28531170.
  6. ^ a b Böhme, Madelaine; Spassov, Nikolai; Ebner, Martin; Geraads, Denis; Hristova, Latinka; Kirscher, Uwe; Kötter, Sabine; Linnemann, Ulf; Prieto, Jérôme; Roussiakis, Socrates; Theodorou, George (2017). "Messinian age and savannah environment of the possible hominin Graecopithecus from Europe". PLOS ONE. 12 (5): e0177347. Bibcode:2017PLoSO..1277347B. doi:10.1371/journal.pone.0177347. PMC 5439672. PMID 28531204.
  7. ^ a b c Daley, Jason (2017-05-23). "Controversial Study Claims Apes and Human Ancestors Split in Southern Europe". Smithsonian Magazine. Retrieved 2021-11-15.
  8. ^ a b c d e f g Barras, Colin (2017-05-22). "Our common ancestor with chimps may be from Europe, not Africa". New Scientist. Retrieved 2017-05-24.
  9. ^ Casanovas-Vilar, Isaac; Alba, David M.; Garcés, Miguel; Robles, Josep M.; Moyà-Solà, Salvador (2011). "Updated chronology for the Miocene hominoid radiation in Western Eurasia". Proceedings of the National Academy of Sciences of the United States of America. 108 (14): 5554–5559. Bibcode:2011PNAS..108.5554C. doi:10.1073/pnas.1018562108. PMC 3078397. PMID 21436034.
  10. ^ a b c de Bonis, L.; Bouvrain, G.; Koufos, G.; Melentis, J. (1986). "Succession and dating of the late Miocene primates of Macedonia". In Lee, P.C.; Else, J.G. (eds.). Primate Evolution. Proceedings of the Tenth Congress of the International Primatological Society: Held in Nairobi, Kenya, in July 1984, International Primatological Society. Congress. 1. CUP Archive. pp. 67–114. ISBN 978-0-521-32450-2.
  11. ^ Simons, E. L. (1981). "Man's Immediate Forerunners". Philosophical Transactions of the Royal Society of London. Series B, Biological Sciences. 292 (1057): 21–41. ISSN 0080-4622.
  12. ^ von Freyberg, B. (1951). "Die Pikermi-fauna von tour la Reine (Attica)". Annales géologiques des Pays Helléniques. 1 (3): 7–10.
  13. ^ Cameron, David W. (1997). "The taxonomic status of Graecopithecus". Primates. 38 (3): 293–302. doi:10.1007/BF02381616. S2CID 28982498.
  14. ^ a b Martin, L.B.; Andrews, P. (1984). "The phyletic position of Graecopithecus freybergi Koenigswald". Courier Forschungsinstitut Senckenberg. 69: 25–40.
  15. ^ a b Koufos, George D.; de Bonis, Louis (2005). "The Late Miocene hominoids Ouranopithecus and Graecopithecus. Implications about their relationships and taxonomy". Annales de Paléontologie. 91 (3): 227–240. Bibcode:2005AnPal..91..227K. doi:10.1016/j.annpal.2005.05.001.
  16. ^ Smith, Tanya M.; Martin, Lawrence B.; Reid, Donald J.; de Bonis, Louis; Koufos, George D. (2004). "An examination of dental development in Graecopithecus freybergi (=Ouranopithecus macedoniensis)". Journal of Human Evolution. 46 (5): 551–577. CiteSeerX 10.1.1.693.116. doi:10.1016/j.jhevol.2004.01.006. PMID 15120265.
  17. ^ de Bonis, Louis; Melentis, Jean (1977). "Les primates hominoides du Vallésien de Macédoine (Grèce). Étude de la machoire inférieure". Geobios. 10 (6): 849–885. Bibcode:1977Geobi..10..849D. doi:10.1016/S0016-6995(77)80081-8.
  18. ^ Koufos, G. D. (1993). "Mandible of Ouranopithecus macedoniensis (Hominidae, Primates) from a new late miocene locality of Macedonia (Greece)". American Journal of Physical Anthropology. 91 (2): 225–234. doi:10.1002/ajpa.1330910208. PMID 8317563.
  19. ^ de Bonis, L.; Bouvrain, G.; Geraads, D.; Koufos, G. (1990). "New hominid skull material from the late Miocene of Macedonia in northern Greece". Nature. 345 (6277): 712–714. Bibcode:1990Natur.345..712D. doi:10.1038/345712a0. PMID 2193230. S2CID 4259387.
  20. ^ Cameron, David W. (1997). "The taxonomic status of Graecopithecus". Primates. 38 (3): 293–302. doi:10.1007/BF02381616. S2CID 28982498.
  21. ^ Cameron, D. W. (1997). "A revised systematic scheme for the Eurasian Miocene fossil Hominidae". Journal of Human Evolution. 33 (4): 449–477. doi:10.1006/jhev.1997.0145. PMID 9361253.
  22. ^ Ioannidou, Melania; Koufos, George D.; de Bonis, Louis; Harvati, Katerina (2019). "A new three-dimensional geometric morphometrics analysis of the Ouranopithecus macedoniensis cranium (Late Miocene, Central Macedonia, Greece)". American Journal of Physical Anthropology. 170 (2): 295–307. doi:10.1002/ajpa.23900. PMID 31339568. S2CID 198194561.
  23. ^ Güleç, Erksin Savas; Sevim, Ayla; Pehlevan, Cesur; Kaya, Ferhat (2007). "A new great ape from the late Miocene of Turkey". Anthropological Science. 115 (2): 153–158. doi:10.1537/ase.070501. ISSN 0918-7960.
  24. ^ Andrews, Peter (2020). "Last Common Ancestor of Apes and Humans: Morphology and Environment". Folia Primatologica. 91 (2): 122–148. doi:10.1159/000501557. PMID 31533109. S2CID 202687516.
  25. ^ Gilbert, Christopher C.; Pugh, Kelsey D.; Fleagle, John G. (2020), Prasad, Guntupalli V.R.; Patnaik, Rajeev (eds.), "Dispersal of Miocene Hominoids (And Pliopithecoids) from Africa to Eurasia in Light of Changing Tectonics and Climate", Biological Consequences of Plate Tectonics: New Perspectives on Post-Gondwana Break-up–A Tribute to Ashok Sahni, Vertebrate Paleobiology and Paleoanthropology, Cham: Springer International Publishing, pp. 393–412, doi:10.1007/978-3-030-49753-8_17, ISBN 978-3-030-49753-8, S2CID 229622942, retrieved 2021-11-16
  26. ^ Almécija, Sergio; Hammond, Ashley S.; Thompson, Nathan E.; Pugh, Kelsey D.; Moyà-Solà, Salvador; Alba, David M. (2021). "Fossil apes and human evolution". Science. 372 (6542): eabb4363. doi:10.1126/science.abb4363. PMID 33958446. S2CID 233872889.
  27. ^ "Scientists find 7.2-million-year-old pre-human remains in the Balkans". Phys.org. 22 May 2017. Retrieved 23 May 2017.
  28. ^ a b Dickinson, Kevin (20 April 2019). "New fossils suggest human ancestors evolved in Europe, not Africa: Experts argue the jaws of an ancient European ape reveal a key human ancestor". NPR. Retrieved 20 April 2019.
  29. ^ Barras, Colin (2017). "Did we split from chimps in Europe?". New Scientist. 234 (3127): 6. Bibcode:2017NewSc.234....6B. doi:10.1016/S0262-4079(17)31000-X.
  30. ^ Begun, David R. (1994). "Relations among the great apes and humans: New interpretations based on the fossil great ape Dryopithecus". American Journal of Physical Anthropology. 37 (S19): 11–63. doi:10.1002/ajpa.1330370604.
  31. ^ Begun, David R. (2010). "Miocene Hominids and the Origins of the African Apes and Humans". Annual Review of Anthropology. 39 (1): 67–84. doi:10.1146/annurev.anthro.012809.105047. ISSN 0084-6570.
  32. ^ Cameron, David W.; Groves, Colin P. (2004-07-08). Bones, Stones and Molecules: "Out of Africa" and Human Origins. Elsevier. pp. 52, 54. ISBN 978-0-08-048841-7.
  33. ^ Benoit, Julien (2017-05-25). "There's not enough evidence to back the claim that humans originated in Europe". The Conversation. Retrieved 2021-11-18.
  34. ^ a b c d Benoit, Julien; Thackeray, Francis J. (2017). "A cladistic analysis of Graecopithecus". South African Journal of Science. 113 (11/12): 2. doi:10.17159/sajs.2017/a0238. ISSN 1996-7489.
  35. ^ Haile-Selassie, Yohannes; Melillo, Stephanie M. (2015). "Middle Pliocene hominin mandibular fourth premolars from Woranso-Mille (Central Afar, Ethiopia)". Journal of Human Evolution. 78: 44–59. doi:10.1016/j.jhevol.2014.08.005. PMID 25200889.
  36. ^ Bermúdez de Castro, J. M.; Nicolás, M. E. (1996). "Changes in the lower premolar-size sequence during hominid evolution. Physlogenetic implications". Human Evolution. 11 (3): 205–215. doi:10.1007/BF02436624. S2CID 85305420.
  37. ^ Brimacombe, Conrad S.; Kuykendall, Kevin L.; Nystrom, Pia (2015). "Epiphyseal fusion in Pan troglodytes relative to dental age". American Journal of Physical Anthropology. 157 (1): 19–29. doi:10.1002/ajpa.22684. PMID 25532866.
  38. ^ Bromage, Timothy G. (1987). "The biological and chronological maturation of early hominids". Journal of Human Evolution. 16 (3): 257–272. doi:10.1016/0047-2484(87)90002-9.
  39. ^ Moyà-Solà, Salvador; Köhler, Meike; Alba, David M.; Casanovas-Vilar, Isaac; Galindo, Jordi (2004). "Pierolapithecus catalaunicus, a New Middle Miocene Great Ape from Spain". Science. 306 (5700): 1339–1344. Bibcode:2004Sci...306.1339M. doi:10.1126/science.1103094. PMID 15550663. S2CID 129576842.
  40. ^ Finarelli, John A.; Clyde, William C. (2004). "Reassessing hominoid phylogeny: evaluating congruence in the morphological and temporal data". Paleobiology. 30 (4): 614–651. doi:10.1666/0094-8373(2004)030<0614:RHPECI>2.0.CO;2. S2CID 86034107.
  41. ^ a b Fuss, Jochen; Spassov, Nikolai; Böhme, Madelaine; Begun, David (2018-05-30). "Response to Benoit and Thackeray (2017): 'A cladistic analysis of Graecopithecus'". South African Journal of Science. 114 (5/6). doi:10.17159/sajs.2018/a0267. ISSN 1996-7489. S2CID 90898690.