See discussions, stats, and author profiles for this publication at: https://www.researchgate.net/publication/262923425 The late Miocene hominoids Ouranopithecus and Graecopithecus. Implications about their relationships and taxonomy. Conference Paper · January 2004 CITATIONS READS 7 228 2 authors: George D. Koufos Louis de Bonis Aristotle University of Thessaloniki Université de Poitiers 330 PUBLICATIONS 5,093 CITATIONS 224 PUBLICATIONS 4,588 CITATIONS SEE PROFILE SEE PROFILE Some of the authors of this publication are also working on these related projects: Oligocene and Miocene carnivoes - Miocene Primates View project The Fossil Vertebrates from Greece View project All content following this page was uploaded by George D. Koufos on 18 October 2015. The user has requested enhancement of the downloaded file. 5th International Symposium on Eastern Mediterranean Geology Thessaloniki, Greece, 14-20 April 2004 The late Miocene hominoids Ouranopithecus and Graecopithecus. Implications about their relationships and taxonomy Koufos G.D.1 & Bonis L. de.2 1Laboratory of Geology and Palaeontology, Department of Geology, University of Thessaloniki, GR-54124, Thessaloniki, Greece, [email protected] 2Laboratoire de Geobiologie, Biochronologie et Paléontologie Humaine. Université de Poitiers, 40 av. du rect. Pinneau, FR-86022, Poitiers, France, [email protected] Keywords: Ouranopithecus, Graecopithecus, Hominoids, Greece, relationships, taxonomy Introduction Two Miocene hominoids are known in Greece, Ouranopithecus macedoniensis from Northern Greece and Graecopithecus freybergi from Southern Greece. Ouranopithecus was known from three localities. On 1973 it was originally found in the locality “Ravin de la Pluie” (RPl) of Axios valley , while later it was recognized in the locality “Xirochori 1” (XIR) in Axios valley too. On 1990 it was recorded to the locality “Nikiti 1” (NKT) in Chalkidiki Peninsula. All these localities are dated to late Vallesian and more precisely from 9.6-8.7 Ma (Bonis & Koufos, 1999; Sen et al., 2000). Several maxillary and mandibular remains have been unearthed from RPl, a partial skull is known from XIR, while a maxilla and a mandible of an old female indi- vidual from NKT. Graecopithecus was found in the locality “Pyrgos Vassilissis” (PYV), near Athens and it is known by a sole mandible almost toothless. The right worn m2, the base of the crown of the right m1, and the lingual surface of the right p4 are preserved. The occlusal border of the right m2 is also partially damaged. The horizontal rami of the mandible are weathered in their inferior border and the external symphysis is also absent (Martin & An- drews, 1984). Since the middle of 1980’s several discussions have been done on the synon- ymy of the two genera. Ouranopithecus macedoniensis and Graecopithecus freybergi syn- onymized and included both into Ankarapithecus metai, while the genus Ankarapithecus was considered as synonym of Sivapithecus; all the taxa being referred under the name Sivapith- ecus metai (Martin & Andrews, 1984). Later on, Ouranopithecus and Graecopithecus sepa- rated from Sivapithecus and referred as Graecopithecus freybergi (Andrews et al., 1996), while Cameron (1997) distinguishes two species: Graecopithecus freybergi and G. macedo- niensis. Few years later the name Ankarapithecus became valuable again, separated from Sivapithecus (Alpagut et al., 1996).Thus, there is a puzzle of the generic and specific names of the Miocene hominoids of Greece and Turkey. In the present article we shall try to show that Graecopithecus mandible is different from Ouranopithecus, while its bad preservation with limited morphology and dental characters cannot allow certain comparisons and results. Comparison of Ouranopithecus and Greacopithecus The size of the premolars and the roots of the canine suggest that the PYV mandible is probably female (Martin & Andrews, 1984). This assumption is not certain as the roots of the canine cannot give certain results, while the premolars are present only by their worn base. Even, a small canine cannot suggest a female individual because the male’s size is unknown. Thus, a small canine can belong to a female individual of a larger male or to a male individual of a smaller female. The synonymy of the two genera was based on the similar size, man- dibular robusticity, enamel thickness and the proportions of the molars (Martin & Andrews, 1984). The size of the PYV mandible would be similar to that of the female Ouranopithecus, Ref: T8-10 5th International Symposium on Eastern Mediterranean Geology Thessaloniki, Greece, 14-20 April 2004 but all the absolute dimensions of the PYV mandible are smaller than the female sample of Ouranopithecus. The comparison of the mandibular robusticity of the two genera (Fig. 1) indi- cates that the PYV mandible is remarkably more gracile than the female and also more grac- ile than the male one of Ouranopithecus. Moreover, it is more gracile than the other Miocene hominoids (Proconsul, Dryopithecus, Ankarapithecus) as well as than A. afarensis. The PYV mandible has similar enamel thickness to Ouranopithecus but also to Ankarapithecus and probably to any other late Miocene hominoid of Eastern Mediterranean. During late Miocene the palaeoenvironment in Eastern Mediterranean was relatively open (Bonis et al., 1992) and all the hominoids would have thick enamel as an adaptation to hard food. The proportions of Graecopithecus molars (broad m2 and enlarged m3) are not certain character as their calcu- lation is based to estimated or to the alveole’s dimensions. The calculation of the index Widthx100/ Length for m2 and m3 indicates that Graecopithecus is closer to the mean values of Ouranopithecus and smaller than the female’s values. Although this similarity, the PYV in- dices are into the ranges of variation and close to the mean values of Ankarapithecus and Sivapithecus, as well as near the minimum values of male Gorilla. Moreover, the PYV mandi- ble has completely different morphology of the internal symphysis from that of Ouranopith- ecus. In the former taxon the internal symphysis is vertical and straight with slight superior torus. On the contrary in Ouranopithecus there is well developed and flat planum alveolare roughly inclined backwards, strong superior torus and well developed fossa genioglossa. In occlusal view the shape of the PYV mandible is different than Ouranopithecus being nar- rower. The width of the mandible in the labial alveole of the various teeth is compared with other hominoids. It is clear that Graecopithecus is narrower than both male and female man- dibles of Ouranopithecus, as well as than Dryopithecus, while it is closer to Proconsul and Ankarapithecus (Fig. 2). MANDIBULAR ROBUSTICITY (MR) 105 95 85 75 X INDE 65 55 45 35 MR at p4 MR at m1 MR at m2 MR at m3 Figure 1. Mandibular Robusticity (MR) of various Miocene hominoids and Australopith- ecus afarensis. ▲=Ouranopithecus, male; ∆=Ouranopithecus, female; - - - =Ouranopithecus, males and females; ◊=Graecopithecus (Martin & Andrews, 1984); ♦=Proconsul (Andrews, 1978); ●=Dryopithecus (from cast of D. fontani); □=Ankarapithecus (Alpagut et al., 1996); *= Australopithecus afarensis (White & Johan- son, 1984). Discussion The above comparison of Graecopithecus with Ouranopithecus suggested that the main ar- guments referred by Martin & Andrews (1984) about the synonymy of the two genera are doubtful or unclear. On the contrary, there are some clear morphological characters (internal Ref: T8-10 5th International Symposium on Eastern Mediterranean Geology Thessaloniki, Greece, 14-20 April 2004 OCCLUSAL SHAPE OF THE MANDIBLE 60 ) m m 55 ( S LE O 50 E V AL 45 AL RN E 40 INT E TH 35 N E E W T 30 H BE 25 DT I AR W 20 UL IB D 15 MAN 10 Bc Bp3 Bp4 Bm1 Bm2 Bm3 lingual Bm3 distal Figure 2. Mandibular width between the internal alveoles of the various teeth. ▲=Ouranopithecus, male; ∆=Ouranopithecus, female; ◊=Graecopithecus (from a cast); ♦=Proconsul (Andrews, 1978); ●=Dryopithecus (from cast of D. fontani); □=Ankarapithecus (from the illustration of Alpagut et al., 1996). symphysis, mandibular robusticity, occlusal shape of the mandible), which can separate the two taxa. Some authors do not accept that the PYV mandible is so incomplete (Andrews et al., 1996; Cameron, 1997). But, the same authors, in their original description of the mandible, refer several damages, weathering of the teeth and bone, absence of several mandibular morphologies (Martin & Andrews, 1984). Cameron (1997) refers that “without additional mate- rial of Graecopithecus freybergi …..there is no evidence to support the recognition of two large bodied hominid genera within the Miocene of southern and northern Greece”. It means that the PYV mandible is so incomplete being not enough to identify a valuable taxon. It is true, but then he puts Ouranopithecus in synonymy with Graecopithecus. Our opinion is that such an incomplete specimen cannot be used for certain comparative determinations and must remain separate. The same authors refer that “Other apparent differences (between the two taxa) may be the result of deformation of the Pyrgos jaw” (Andrews et al., 1996). But, why the deformation affects only the differences and not the similarities between the two taxa? Cameron (1997) refers: "in accepting Ouranopithecus and simply ignoring Graecopithecus, we are indirectly accepting two genera of large-bodied hominids in Greece (i.e. Ouranopith- ecus from Macedonia and Graecopithecus from southern Greeece) when there may be no strong reason