tobias 1999 - commentary on the case for early pleistocene hominids in south-eastern spain

8/6/2019 TOBIAS 1999 - Commentary on the Case for Early Pleistocene Hominids in South-Eastern Spain

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Commentary on the case for Early PleistoceneHominids in South-Eastern Spain

Phillip V. TOBIASOMSG. FRS (Professor Emeritus)Palaeo-anthropology Research Group,Department of Anatornical Sciences,

University of the Witwatersrand,Johannesburg, South Africa

At least two sets of remains from the Orce (Granada; district of South-Eastern Spain have been claimed toindicate the presence of hominids in that area in the Earlv Pleistocene. over one millon years ago. From my ownobservations on the original specimens, from the published evidence such as the volumes edited by Josep Gibert-Clols (1989, 1992) and from the independent analvsis by Derek A. Roe of Oxford University (1995), it maybe stated that those remains from Venta Micena pose a somewhat tantalising challenge, whilst those from FuenteNueva 3a are less problematical.These comments were penned in June 1997, nearlv two vears after the Orce Conference took place inSeptember 1995. As my views were being freely cited in Spain and elsewhere, mainly from correspondence, inthe period following the Orce Conference, it \vas deemed to be useful to set down at first hand my interpretationof the evidence bearing on the early Pleistocene remains from South-Eastern Spain.

VENTA MICENA: THE SKELETAL EVIDENCE

Three specimens are available: a biparieto-occipital calvarial fragment (VM-0), and two long bones comprisinga juvenile diaphysis or shaft (VM-1960) of what has been claimed to be a juvenile humerus and a probable adultportion of the shaft of a putative humerus (VM-3691). All three specimens have been claimed to be of humancharacter (Gibert et al., 1989; Campillo 1992; Gibert et al. 1994a, 1994b; Gibert and Palmqvist, 1995). Theywere recovered from Estrato Blanco of the Venta Micena formation.My brief examination of the original humeral specimens was made at Orce in September 1995, and wassupplemented by the published morphological and quantitative data on these two specimens. Despite theirincompleteness, it seems to me that the features of the available parts of the fossil specimens are compatible withtheir being humeri. I have no difficulty in accepting that the morphology of the two fossil humeri s in keepingwith their being of hominid origin.As regards the calvarial portion, 1 was aware, at the time when I examined the original specimen, that ithad been suggested that this was derived from an equid skull and not from a hominid skull, a view which hasapparently been espoused by several colleagues. Some features of the calvarial fragment are worthy of specialmention. One is a crest which lies on the inner surface of the posterior part of the specimen, reaches 5.5 mmin its maximum elevation, lies in or very close to the median sagittal plane (the midline plane of the calvaria)and is hollowed or concave on its right face and convex on its left face. In modern human crania we find inthis position one or both lips of the superior sagittal sinus groove, which in life lodges the great venous sinusthat travels from anterior to posterior in or close to the midline of the calvaria. In a recent human anatomicalspecimen, the sinus enlarges from anterior to posterior. Hence the groove on the endocranium widens anddeepens from front to back, so that, by the time the occipital bone is reached, the lips or at least one of thetwo lips is at maximum prominente. This is precisely the position where the strong lip or crest is present in theVenta Micena calvaria.It would be unusual to find in modern human crania a crest as elevated as that ofVM-0; but the palaeopathologist,Domingo Campillo (1989, 1992), from a of study over a thousand recent human crania -both dried anatomicalspecimens and cranial radiographs of modern human subjects- has found sinus groove lips as prominent as thatof VM-0 in some modern humans. Thus, this factor on its own s insufficient to disqualify the calvaria of VentaMicena from hominid status.A second feature that was of concern to me in my examination of the original calvarial fragment, as wellas of a cast and endocranial cast which Professor Gibert generously gave to me, was the nature of the endocranial

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impressions in the region of the superior parietal lobule of the cerebrum (Tobias, 1997). When I "read" theseimpressions with eye and fingertip, it seemed to me that the endocranial marking of the superior parietal lobulevas divided rather sharply into two moieties, an anterior and a posterior, by a transverse crest which would havecorresponded with a sulcus crossing the lobule transversely. This transverse crest did not appear to represent thelissura parieto-occipitalis. However, it is entierely possible that this transverse crest represented the pars marginalissulci cinguli, in a case in which this marginal part was better developed than is usual in most modern human brainsthat I have examined. Hence, this endocranial pattern 00 its own does not disqualify the specimen from hominididentity.There were thus two anatomical features of the calvaria VM-0 which appeared to be unusual, if thisfragment had belonged to a human-like cranium. Neither of these two features is sufficent to disqualify thespecimen from having belonged to a hominid: I stated this at Orce, at the time when I examined the originalspecimen in September, 1995. However, in respect of both of these features, it must be admitted that we havevery little available information on the variability of these two anatomical traits in the hominids that were livingin the early Pleistocene. If we take into account the known range of variability of these two traits in modernhuman crania, both features could be accommodated within the range of modern humans. I have net studiedthe range of variation of these two features in modern equid crania of young or adult equid specimens.Another morphological variable about which there has been controversy, is the pattern of the sagittal sutureof the calvaria VM-0. The original fractal analysis of the suture by J. Gibert and P. Palmqvist (1995) pointedstrongly to its hominid affinities. However, doubts have subsequently been expressed on the basis of a differenttracing of the sanee sagittal suture (Palmqvist 1997). It is possible that one of the two tracings has been madeon the endocranial surface, in contrast with the other tracing which might have been made on the ectocranialsurface of VM-0. The structure of the sagittal suture may vary appreciably betwen the two surfaces in modernand ancient hominid crania. Moreover, changes in the patterns of the sagittal suture occur with age - and ina different way and at different times on the inner and the outer surfaces of the cranial bone. Obviously, differentconclusions would be expected if one studied the patterns of the sagittal suture internally, from what would belearned if one studied the pattern externally. However, even if both tracings ofVM-0 are ectocranial, as Palmqvist(1997) avers, it remains true that the sutural pattern is highly variable from cranium to cranium on both theendocranial and the ectocranial surfaces of the calvaria. We know a good deal about the variability of this suturein some (but not all) populations of modern humans. I doubt whether we have such detailed information onthe ontogenetic and inter-individual variability of the sagittal suture in modern and ancient menibers of thehorse family. Moreover, we have little information on the variations of the sagittal suture in earlier taxa ofhominids, such as Horno erectus, Neandertal populations, or even the so-called archaic Horno sapiens. For thesereasons, the study of this suture, even by the modern, refined technique of fractal analysis, is not very likely tothrow definitive light on the systematic (taxonornic) affinities of the individual represented by VM-0. On the basisof presently available knowledge, even if were possible to control for the age of an individual, and for the surfacetraced and studied, it seems most doubtful and problematical whether it would be valid or accurate for thepattern of the sagittal suture to be used for the identification of the species represented by VM-0.I conclude that the pattern of the sagittal suture does not disprove, nor support, the claim that the craniumwas of a hominid.At Orce, I stated that the morphology of the calvaria VM-0 seemed to be compatible with hominid status,but that without further remains, une could note be 100 % certain. Futher, I stated without qualification thatthe morphology of the two humeri was fully compatible with hominid status. In the two years that have elapsedlince then, I have seen no new evidence that would lead me to change this view. If one considera the threespecimens as an ensemble, their morphology is compatible with hominid structure, and provides evidencepointing to, but not absolutely establishing, the presence of hominids in Venta Micena at the time when theEstrato Blanco of the deposit was formed. This statement is based solely on the anatomical features of the t h reespecimens. I shall now look at the biomolecular and archaeological evidence.

MOLECULAR EVIDENCE FOR EARLY PLEISTOCENE HOMINIDS IN SOUTH-EASTERN SPAIN

At Orce in September 1995, I was more impressed by the evidence of the fossil proteins of the VM bonespecimens, as were determined by the studies of two different groups, using two different technical approaches.One group was that of Jerold Lowenstein, who was a pioneer in the radio-immuno-assay (RIA) of fossils andis recognised as one of the world.'s leading authorities in such studies: his laboratory is in the University of40


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COMMENTARY ON THE CASE FOR EARLY PLEISTOCENE HOMINIDS IN SOUTH-EASTERN SPAIN

California at San Francisco, U.S.A. The other group was that of Concepcion Borja and Enrique Garcia Olivares(1995) of the University of Granada in Spain. Both groups detected human albumin in VM-0 and VM-1960,Lowenstein (1995) detected human collagen and transferrin in V-0, \ vhil e Borja's team detected humanimmunoglobulin in VM-1960 and VM-3691. The convergente of the t \vo laboratories, working independentlyof one another, by two different methods, provides very stron g, evidence in support of the conclusion that thebones from Venta Micena are of hominid origin (Borja et al. 1997). For dais reason. I stated at Orce that theevidence of the fossil proteins was more convincing than of the skeletal morphology, in the establishment of theirhominid origin.When the molecular and the skeletal data are considered together. the picture afforded by the bio-anthropologicalevidence is that the three bones are of human origin. Thus, on their oyen, thev provide evidence that hominidswere present in the Orce region well down in the Early Pleistocene. The case is strengthened when one takesinto account the archaeological evidence, especially that from Fuente Nueva (vide infra).

CULTURAL EVIDENCE FOR EARLY PLEIS'FOCENE HOMINIDS IN SOUTH-EASTERN SPAIN Two kinds of cultural evidence have been adduced by Josep Gibert and his team in support of the presenceof signs of hominid handiwork in the Venta Micena deposit: one relates to the modification of bones by breakage

and cutmarks (Gibert and Jimenez, 1991, Jimenez and Gibert, 1993). From scanning electron microscopic studiesof those bones which were found in situ at Venta Micena and which show apparent cutmarks, and a comparisonof these apparent cutmarks with those previously identified on bones from Olduvai in Tanzania and Lake Turkanain Kenya, they have concluded that the Venta Micena marks are similarly to be regarded as signs of hominidactivities. No other adequate explanation of the marks on the Venta Micena hones has been proffered (Roe,1995), The bones affected were obtained from the Estrato Blanco from which the hominid bones emanated.The second line of cultural evidence relates to stones which have been recovered from Estrato Blanco at VentaMicena and also from the earlier Estrato Negro at several other sites in the vicinity (such as Barranco del Paso-Cortijo Alfonso, Barranco Len and Cortijo de Doa Milagros) (Gibert et al., 1992; Roe, 1995). I haveexamined but not studied these claimed artefacts and manuports, but I am impressed by the critical study byD. A. Roe of the stones which J.Gibert placed at the disposal of himself and his team at the Donald Baden-Powell Quaternary Research Centre, Oxford University. Fractured stones and stone transported to the site arecertainly present and Roe acknowledges that some `struck . surfaces are detectable, as also some struck flakes,although he does not exclude the possibility that they could have been produced by natural mechanical forces.On the other hand, when one considers the sources of various rocks represented in the collection of stone foundamong the Early Pleistocene animal bones, they have all been transported from at least a few kilometres away.Of them, Roe (1995) states, "Apart from human portage, there seems to be no obvious natural explanation (suchas the presence of stream channels) that could account for their presence where they were found. They cannotproperly be rejected as manuports (which Roe defines as "...pieces of stone which were not worked, but whosepresence where discovered is specifically attributable to transport by humans (op. cit., p. 6)) until a goodalternative explanation for their presence has been provided". (Roe, 1995: page 7).Thus, there is suggestive evidence for the presence of the marks of hominid cultural activities at VentaMicena, although on the oasis of the stockpile of material which was available at the time when Derek Roemade his initial independent study, the case had not yet been irrefutably proven. More material needed to berecovered from Venta Micena and to be subjected to the most critical study, such as that to which Jimenez andGibert (1991, 1992) had subjected the cutmarks on the Venta Micena bones.A further study by Tixier, Roe, Turq and others ( 1995) has led the authors "d'affirmer la presence d'outilslithiques taills dans le Plistocne inferieur du sud de la Pninsule Ibrique" ("to assert the presence of lithicartefacts during the Lower Pleistocene in the South of the Iberian Peninsula") (Tixicr et al., pago 71).To summarise on the contribution which Venta Micena has made to our thinking on early hominids inEurope, from that site specifically, the identification -by anatomical and molecular means- of hominid bonesprovides very persuasive evidence that hominids were present at Venta Micena in the Early Pleistocene. Culturalevidence of the hominid presence is provided by the quarzite and silex pieces which were found in stu withthe animal bones, boda the stones which appear to have been modified, and those which were probablymanuports, and by the claimed cutmarks on contemporaneous hones.

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TOI3IAS, Phillip

FUENTE NUEVA

Stronger cultural evidence for the presence of hominids at the sanee early period has been forthcoming fromFuente Nueva 3 in the Orce Basin. Indisputable stone artefacts have been recovered from the sane horizon ashas yielded Early Pleistocene fauna (as has been revealed by the excavation of A. Turq, which is quoted by Roe,1995). Broken stones as well as probable manuports have been found also in the older Estrato Negro at some ofthe other Orce Basin sites, such as Barranco Lon.

COMMENTS

Further investigations of Estrato Blanco and Estrato Negro, at those sites in the Orce Basin where these twostrata are preserved and available for excavation, should be an important objetive for the immediate future.Among the purposes will clearly be the need to recover more hominid skeletal remains, and indisputable stoneartefacts found in association with the Early Pleistocene animal bones, and the confirmation, over a wider area,of the dating that has been claimed for the Orce hominid remains. Josep Gibert and his associates have claimeda dating, based largely on paleomagnetic results, of 1.6-1.8 million years before the present (Gibert et al, 1992).That would be close to the oldest part of the Early Pleistocene as defined at present. The Pliocene-Pleistoceneboundary is placed at 1.8 million years ago, although an INQUA Committee under the chairmanship of T.C.Partridge of Johannesburg, is at present investigating the perceived need for that boundary to be shifted backin time to a little older than 2.0 million years. This claim by Gibert and his associates was discussed at the OrceMeeting in 1995. Some investigators held that the paleomagnetic results were compatible with less ancient datingthan 1.6 million years, but none of the discussants held that it could be less than about 1.2 million years. Evenon this less archaic dating, these are the oldest dates for the hitherto established presence of hominids in Europe.They exceed even the dating of 0.8 million years for the hominid remains from Gran Dolina, Atapuerca (Burgos),in northern Spain, and the possible dating proponed for the cranium of Ceprano, Italy.Already there is evidence from elsewere-Ubeidiya in Israel, Dmanisi in Georgia, Java in Indonesia and,probably also China, for the presence of hominids out of Africa before 1.0 million years ago. Aside from theDmanisi remains (1.4Myr), the Orce Basin has furnished evidence for the presence of the oldest hominids inthe European continent.

SUMMARY

Several sites in the Orce Basin have revealed evidence indicative of the presence of hominids in the EarlyPleistocene. These remains are dated to over 1.0 million years, while they may be as old 1.6 million years.The putative hominid skeletal remains from Venta Micena in the Orce Basin show a molecular "fossilprotein" pattern which aligns them with hominids, but not with equids. This is supported by the anatomicalevidence of the two presumptive humeral shafts from the Estrato Blanco in the Venta Micena deposits. Thebioparieto-occipital partial calvaria shows some unusual anatomical features ifVM-0 is a hominid specimen. Thepresence of a prominent sagittally orientated crest on the interna' surface of the occipital fragment adjacent tothe point lambda is unusual for a modern human calvaria. Moreover, the itnpressiones digitatae, in the regionwhere the superior parietal lobule of the cerebral hemisphere abutted against the calvaria, point to a bipartitesuperior parietal lobule with anterior and posterior moities. On the endocast ofVM-0, these arcas are separatedby a depression that would have rnatched a transverse sulcus on the original brain. These morphological traitsare rather puzzling if VM-0 is a hominid, and at first they led me to hesitate over the systematic identificationof VM-0. However, the studies of Campillo (1989) and of Campillo and Barcel (1989) show that the featuresof the fragment VM-0 are compatible with those of a hominid. Because I believe that we do not possesS sufficientinformation on the variability of the endocranial and ectocranial manifestations of the sagittal suture and of itsvariance with the age of the individual, among different individuals and in different hominid species, nor on thevariability in different equid species, I do not consider that the pattern of the sagittal suture may validly beadduced as evidence in support or rebuttal of the hominid status of VM-0.The biochemical studies of VM-0 by Borja et al. (1992, 1995, 1997) and by Lowenstein (1995, 1997) leavelittle room for doubt that the affinities of the proteins of VM-0 lie with the hominids, not with equids, to thecrania of which VM-0 has been likened by some colleagues. These studies also support the assignment of thehumeral specimens to the hominids.

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The signs of cutmarks on some of the contemporaneous Venta Micena bones, and the evidence of stone-collecting and modifying at Venta Micena Estrato Blanco, as well as at Fuente Nueva-3, add a convincing culturaldimension to the testimony that a tool-using and tool-making hominid was present in the Orce Basin duringthe early Pleistocene, between 1.6 and 1.0 million vears ago.The totality of the evidence, b ological and cultural. from the Orce basin po nts strongly to this conclusion:Orce has provided the first evidence that ancient humans ere present in (Western) Europe

over a million years ago.

A CKNOWLED GEMENT S

I am grateful to the Mayor of Orce (Granada), Mr Leandro Torres Alchapar, whose letter of enquiry to me,dated 26th March 1997, as to my viewpoint on the remains attributed to "Orce Man", stimulated me to writethis Commentary.Dr Josep Gibert i Clols kindly allowed me access to the sites and to the original material from Venta Micenaand from other sites in the Orce Basin. My understanding of the problem of the Orce and Murcia remains hasbeen greatly helped by discussions and exchanges of correspondence with Professor Josep Gibert i Clols, DrDomingo Campillo, Professor Michael Walker, Dr Paul Palmqvist and Dr Bienvenido Martinez Navarro, to allof whom I am most grateful.Mr S'fiso Mthembu kindly typed the manuscript.

REFERENCE S

BORJA C. and GARCIA-OLIVARES E. (1995). Detection and characterisation of proteins in fossils from VentaMicena and Cueva Victoria by immunological methods. International Conference of Human Palaeontology(Orce, Granada), 26.BORJA C., GARCIA-PACHECO J.M., RAMIREZ-LOPEZ J.P. and GARCA-OLIVARES E. (1992).Cuantificacin y caracterizacin de la albumina fsil del crneo de Orce. In: J. Gibert, D. Campillo, E.Garca-Olivares, A. Malgosa, E Martinez and B. Martinez (eds). Proyecto Orce-Cueva Victria (1988-1992).Presencia humana en el Pleistoceno inferior de Granada y Murcia, pp.415-423. Orce (Granada): Museo dePrehistria y Paleontologa "J. Gibert".BORJA C., GARCA-PACHECO J.M., GARCA-OLIVARES E., SCHEUENSTUHL G. and LOWENSTEINJ.M. (1997). Immunospecificity of albumin detected in 1.6 million-years-old fossils from Venta Micena inOrce, Granada, Spain. American Journal of Physical Anthropology. 103: 433-441.CAMPILLO D. (1989). Estudio del Hombre de Orce. In: J. Gibert, D. Campillo and E. Garca Olivares (eds.)Los restos humanos de Orce y Cueva Victria, pp. 187-220. Sabadell: Institut de Paleontologia Dr. M.Crusafont.CAMPILLO D. (1992). Estudio del Hombre de Orce. In: J. Gibert (ed.) Presencia humana en el Pleistoceno inferiorde Granada y Murcia, pp. 341-370. Orce (Granada): Museo de Prehistoria y Paleontologa "J. Gibert".CAMPILLO D. and BARCEL J.A. (1989). Morphometric study of the internal surface of the squama occipitalis.In: J. Gibert, D. Campillo and E. Garca Olivares (eds.) Los restos humanos de Orce y Cueva Victoria, pp .109-186. Sabadell: Institut de Paleontologa M. Crusafont.GIBERT, J. (ed.) (1992). Proyecto Orce-Cueva Victoria (1988-1992): Presencia humana en el Pleistoceno inferior deGranada y Murcia. Orce (Granada): Museo de Prehistria y Paleontologa "J. Gibert".GIBERT J., ARRIBAS A., MARTINEZ B., ALBADALEJO S., GAETE R.,GIBERT L., PEASAS C., andTORRICO R. (1992): Sintesis cronoestratigrfica del Pleistoceno inferior de la regin de Orce. In: J.Gibert (ed.) Proyecto Orce-Cueva Victoria (1988-1992): Presencia humana en el Pleistoceno inferior de Granaday Murcia. pp. 107-112. Orce (Granada): Museo de Prehistria y Paleontologa "J. Gibert".GIBERT J., ARRIBAS A., MARTINEZ B., ALBADALEJO S., GAETE R., GIBERT L., OMS O., PEASAS C.,and TORRICO R., (1994 a). Biostratigraphie et magntoestratigraphie des gisements presence humaineet action anthropique du Plistocene infrieur de la rgion d'Orce (Granada, espagne). C.R. Acad. Sci.Paris III 318: 1277-1282.GIBERT J., CAMPILLO D. and GARCA OLIVARES E. (eds.) (1989). Los restos humanos de Orce y CuevaVictria. Sabadell: Institut de Paleontologa M. Crusafont.

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GIBERT J. and JIMENEZ C. (1991). Investigations into cut-niarks on fossil bones of Lower Pleistocene agefrom Venta Micena (Orce, Granada, Spain). Human Evolution, 6: 117-128.GIBERT J. and PALMQVIST P. (1995). Fractal analysis of the Orce skull sutures. J.Hum. Evol., 28: 561-575.GIBERT J., SNCHEZ E, MALGOSA A., and MARTNEZ B. (1994 b). Dcouverte des restes humaines dansle gisement d'Orce (Granada, Espagne). C.R. Acad. Sci. Paris, III 319: 963-968.JIMENEZ C., and GIBERT J. (1993). Estudio comparado de los "cut-marks" de Venta Micena. In Gibert J.(ed.). Proyecto Orce-Cueva Victdria (1988-1992): Presencia humana en el Pleistoceno inferior de Granada y Murcia,pp. 307-339. Orce,Granada: Museo de Prehistoria y Paleontologa "J. Gibert".LOWENSTEIN J. (1995). Immunological reactions in fossil bones from Orce. Congreso Internacional de PaleontologaHumana. Orce, Granada, Spain, September 1995.PALMQVIST P. (1997).A critical re-evaluation of the evidence for the presence of hominids in Lower Pleistocenetimes at Venta Micena, Southern Spain. J. 1114111. Evol., 33: 83-89.ROE D.A. (1995). The Orce Basin ( Andaluca, Spain) and the initial palaeolithic of Europe. Oxford J. Archaeology,14 (1): 1-12.TIXIER J., ROE D ., TURQ A., GIBERT J., MARTINEZ B., ARRIBAS A., GIBERT L., GAETE, R.,MAILLO, A., and IGLESIAS, A. (1995). Presence D'industries lithiques dans le Plistocene infrieur dela rgion d'Orce (Grenade, Espagne): quel est l'tat de la question? C. R. Acad. Sci. Paris, II: 71-78.TOBIAS P.V. (1998).Were the lower and middle Pleistocene Europeans capable of spoken language? In: Homnidsand their Environment in the European Lower and Middle Pleistocene (ed. J. Gibert). Proceedings of InternationalCongress of Human Palaeontology, Orce, Spain, September 1995.

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tobias 1999 - commentary on the case for early pleistocene hominids in south-eastern spain

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