The Chronology of the New World:
two faces of one reality
by N. Guidon and B. Arnaud
The paper gives a review of archaeological work in the south-eastern part of Piaui State, Brazil, with particular reference to the chronology and geological history of rockshelter sites, such as Toca do Boqueirão da Pedra Furada, and Toca do Sitio do Meio. The article analyses critiques of early dates in South America, notes a bias towards the rejection of early dates, and gives additional documentation to the early dates in Piaui State. It concludes by urging that a new consensus be developed among archaeologists studying early American sites.
The chronology of the earliest period, of occupation in the New World is a subject of intensive controvesy. In the endless debate one might reflect that everything seems to have been said already. The situation does not change each time there is a new discovery, unfailingly the dehate takes up again around the same arguments. This results in dogmatic positions and a climate of ideological fervour. Today, it seems to us that we have no hope of writing an article ahout the chronology of Pleistocene America which will not convince the convinced, and augment the suspicions of the sceptics! Yet it is time for the 'cold war' of Americanist archaeology to come to an end; the two camps - those favouring early colonization, and those setting a limit at 12,000-14,000 before present - must seek out in collaboration the evidence necessary for building up a cultural sequence which can be accepted as the only really accurate record of the peopling of the continent
In this paper, as our contribution to such an exercise, we review the work of our own expedition in Piaui (Brazil), and the arguments for and against the evidence which we have revealed.
A climate of scepticism
First we draw attention to the climate of ,cepticism attending old dates. Reviewing work mried out in the Old Crow hasin of north-west Canada, Guthrie (1984) begin" The following critique deal, only with the Pleistocene archaeological interpretatio", pertaining to the Old Crow osteological material and is not intended to reflect negatively on the excellent paleontological, taphonomic, paleoecological, paleoclimatic, geographic, stratigrapt,ic and Holocene archaeological studies which have been and are being carried out by highly qualified Old Crow Basin re"arch team'.
One may wonder how 'highly qualified' teams can carry out excellent interdisciplinary work in the Holocene levels, and then suddenly to be unable to recognize the stratigraphic details, the signs of climatic change and the palaeontological evidence, the moment they come to the Pleistocene. In another example Guthrie (1984) declares that 'Beringia is tbe only realistic route for human entry to the New World', but he gives no explanation of what exactly 'realistic' means. Why should this have been the only route of entry? Everybody is willing to give humans the abilities necessary for voyaging across to Australia about 60,000 years ago. Why then would it have been impossible for them to pass from island to island along the Aleutians, just as one example? We have no justification for converting the humans who peopled the Americas to a single state of being, where they could do nothing but follow herds by a land route. Schmitz (1987) expresses his scepticism about radiocarbon dates older than 13,000 years nefoe the present, stating that 'their reliability is uncertain', but giving no analysis and presenting no justification. Our own work has not escaped this kind of judgement - Schmitz continues (1987: 63), in relation to the old dates from Toca do Boqueirão da Pedra Furada: the two earliest stages proposed by Guidon antedate the oldest generally accepted dates for humans in South America. This situation makes it necessary to view with caution both the antiquity and the sequence. The stratigraphy, artifacts and carbon samples are all subject to misinterpretation.
Such comments reflect a widespread bias against archaeological interpretations and facts relating to the early periods; new statements are accepted without any great fuss, and often with little foundation, provided that they conform with the classic theory which fixes the limit of acceptable dates for South America at 12,000 years. For twenty-one years our expedition has worked in Brazil, in the south-eastern part of Piaui State. For the Holocene, our results have never provoked controversy, even though we have discovered new aspects of culture. The unexpected age of a certain pottery type, and the ages of rock paintings covered by archaeological layers dating to 10,500 BP have drawn no reaction - even though rock paintings and pottery have always been considered as very recent features in the prehistory of North-eastern Brazil.
In spite of the bias seen above, we know now that Homo sapiens sapiens has an antiquity of 100,000 to 90,000 years in the Old World, and must concede that this is sufficient to allow the possibility that humans were in America from 70,000 to 50,000 years ago.
North-eastern Brazil showing the area of São Raimundo Nonato.
The excavations at Toca do Boqueirão da Pedra Furada
The area of São Raimundo Nonato in the south-eastern part of Piaui State occupies a region of broken country between the sedimentary basins of Piaui-Maranhão and the São Francisco river. All along the cuesta front which separates the two basins, and in the valleys inside the basins, thousands of rockshelters have formed - hundreds of which have traces of prehistoric human activity (Guidon and Delibrias 1985, 1986; Delibrias et al. 1988). For over twenty years we have carried out investigations in this area. We will give a rapid review of the excavations undertaken in the great rockshelter of Toca do Boqueirão da Pedra Furada (42o 33' 30" W, 8o 50' S) between 1978 and 1988.
The rockshelter is over 70 meters long. The initial area of excavation, up against the rockwall of the site, measured 7 m by 3 m. The subsequent seasons of work raised the extent up to 700 square metres, through an average depth of 4 metres. From 1978 to 1983 we encountered problems in interpreting the stratigraphy in the western part of the site. The Holocene layers were well preserved, but in the east they had been eroded. In contrast, the Pleistocene layers had been partly destroyed in the west, whereas to the east they were perfectly preserved, since they were protected by blocks fallen from the shelter roof. The slopes ofthe layers presented a complex picture, highly variable from place to place. It was only in 1983, after discovering a mass of fallen rocks almost directly in contact with the rocky floor, that we were able to understand how the site had been formed. This basic discovery allowed us the certainty that we had primary archaeological layers which had not been disturbed by erosion.
Let us pause for a moment over this assertion: it is effectively almost impossible to interpret a stratigraphic sequence, or the association between a charcoal sample and stone tools, if one is working in a small test-pit. Unfortunately a high proportion of American excavations are carried out using the technique of test-pits, and only small areas are excavated. Our experience at Pedra Furada is much more conclusive: we would never have been able to make interpretations with assurance or work out the details of deposition without uncovering the site almost completely.
The great abri (rockshelter) of Boqueirão da Pedra Furada was thus formed in the following manner, beginning with a major rockfall about 60,000 years ago. The rockfall isolated the part of the site under the overhang from the slope down to the valley (the shelter is situated 19 metres above a plain, and so safe from all flooding). Sands composed of material derived from the sandstone shelter walls then began to be deposited over the rockfall. The first humans arrived at the site, perhaps drawn by the presence of a water source towards the west, in the depths of a vertical crevice funneling water down from the plateau above. This water course was probably responsible for the erosion which destroyed the outer part of the Pleistocene layers, but it never penetrated the area of the archaeological site.
Plan and section of Toca do Boqueirão da Pedra
It appears that the first inhabitants then cleared a level area, using fire to break up the largest boulders. These events were not forest fires: the boulders destroyed were only those by the shelter wall, under the overhang, and none of the boulders isolating the shelter from the valley were touched. The first campsite thus lay protected between the pile of boulders and the back wall of the shelter. As the ancient rocks of the plateau are composed of conglomerates, the violent torrents of water which occurred during wet periods were able to transport quartz and quartzite pebbles downwards. As we have already explained, these pebbles were unable to fall down into the shelter, except for the outer parts which were not protected by the overhang. Under the overhang the only sediments are sands derived from the sandstone of the cliffs. In their fall, the pebbles sometimes broke naturally, forming flakes which are often larger than those produced in human stoneworking. A flake formed as the result of such a fall thus remains outside the covered part of the site. There is no possibility that such a flake could cross the wall of boulders and enter the interior of the shelter without human transport.
Radiocarbon (C14) dates in years before the present and correlation between divisions and sedimentological layers for the site of Pedra Furada.
In the area of human habitation, the flakes and other stone pieces are concentrated primarily around the edges of structures which contain charcoal. These structures were situated close to the shelter wall, and were made up of fragments of rock derived from it, and large cobbles (these could not have fallen in from outside the shelter, for the reasons already given). Large excavations made outside the overhang have not revealed any similar structures. Outside the shelter, in the talus, charcoal was rare and sparse. The features are therefore interpreted as hearths, and we regard any hypothesis invoking forest fires as quite impossible, since, whatever else, these would have had to move from the outside to the inside.
Over thousands of years the sediments accumulated gently, covering the boulders of the rockfall. Then around 22,000 to 18,000 years ago there was a further rockfall on the eastern side, creating a new entry for water to plunge down from the plateau. This ran along the edge of the shelter area, then changed its course at the middle of the shelter, finally taking the direction of the talus, down to the plain. It did not encroach upon the inhabited areas cose to the shelter wall. Another watercourse existed on the easlern side, around 12,000 to 11,000 years ago. Because of the topography of the site, the water in this new channel only ran in the eastern area.
Radiocarbon (c14) dates from Pedra Furada seen in relation to stratigraphy and granulometry (courtesy Fabio Parenti, 1991)
In summary. there were times, at different stratigraphic levels, when lorrents of rainwater ran across the east and west margins of the sheltered area, and also on its southern edge, in the direction of the talus - but the areas under the shelter itself have not been subjected to water action, either in the Pleistocene and the Holocene, owing to the palaeotopography of the site, and thanks to the protection offered by the pile of fallen rocks. A summary of the various occupations and dates is given in Table 1. We have given this account of the areas outside the abri. including the walercourses, so as to make comparisons with the area within the overhang. All this work. adding even more data to the mass obtained from a large excavation, allows us to interpret the totality of the depositional processes: and so we are happy to invite specialists in micro-stratigraphy to come and discuss issues on site. At Pedra Furada a favourable conjunction of natural factors allowed major complexes of prehistoric campsites of different ages to succeed one another on the site, and to be preserved intact. These factors include the rockfalls, the shape of the shelter, and the position of the crevasses carrying water. Their relative importance has only been discovered because we have excavated over 70 per cent of the total site area. In an excavation of large extent, it is possible to expose the areas surrounding any structures, and so easier to establish the relationships between them, the charcoal which they contain, and the lithic pieces deposited around them. The geological history of Pedra Furada has been reconstructed by geomorphologists, with whom we have worked for many years studying the stratigraphy and the sequence of formational episodes on the site in great detail. Fabio Parenti is writing a doctoral thesis on the Pedra Furada excavations under the direction of one of us (NG). This will provide much more detail of problems concerning formation of the site over a long period.
Other rock shelters have been investigated in the same area, including the rockshelter of Toca do Sitio do Meio (42o 33' W, 80 49' S), which is less than 2 km from Pedra Furada. The oldest date obtained for the site is 14,300 ± 400 years before the present (GIF-5399). The Holocene levels have been disturbed by modern use of the site, but the Pleistocene levels are sealed, like those at Pedra Furada, by a great rockfall, later than 15,000 before the present , and which we place provisionally at about 12,000 years. The site will be excavated again in 1991, which should allow us to ascertain the extent of the zone of human occupation sealed under the rockfall. Toca do Cima dos Pilao, 2 km from Pedra Furada, is a limestone site. The fossil fauna recovered from such limestone sites shows us that not long ago the area had a quite different climate. Prairies with scattered clumps of trees stretched across the plain, while the rims of the basin, including Pedra Furada, were covered with humid tropical forest. The excavations in the limestone caves have yielded long stratigraphic sequences. In these sediments deposited during drier periods succeed those of wetter periods. The former have not yet been dated, but excavations in Baixao do Perna I, a site on the massif of sediments, may provide answers, as this rockshelter contains almost exclusively Holocene layers. In the final Pleistocene the inhabited part of the site was only 4 m above the valley bottom. There was a rocky surface protected by a shelter wall covered with paintings. This floor was strewn with a cover of cobbles, indicating a former stream of great force. In the rainy seasons the water used to rise and flood the site completely, carrying everything away. Hence, the first hearths which survive probably indicate the end of a very wet period. A date of 10,500 ± 110 before the present (BETA 32971) has already been obtained for one of these hearths, situated 40 cm above the base of the site. This evidence tends to confirm - and it is a working hypothesis - that there was a very wet period about 12,000 years ago. Thus excavations carried out on sites protected from water action (Pedra Furada, Sitio do Meio, Caldeirao dos Rodrigues I) provide dates substantially earlier than 12,000 years, while sites in valley bottoms exposed to erosion preserve only material aged less than 12,000 years. This emphasizes that it is only through the total study of a region, including the systematic excavation of the various kinds of sites, from present-day levels through to their base, that we shall be able to explain in scientific terms the history of human arrival and human evolution in the Americas.
Critiques of the early Brazilian sites: a reply
We start by noting that even the period after 12,000 before the present is viewed in different ways by different authors. The bias against early dates on South American sites is sometimes linked with a tendency to oversimplify evidence. For example, Schmitz (1987) declares that 'the Itaparica tradition, emphasizing well-formed unifacial artifacts, had dispersed over the eastern tropical parklands. An enormous amount and variety of rock paintings and/or engravings are associated with the latter.' In fact, the industries of this 'Itaparica tradition' have never been studied in detail, nor the tradition defined. The present state of research makes plain that this tradition comprises various archaeological complexes and it is impossible to bring together under one label material that is so far separated in time and space. The association between 'rock paintings and/or engravings' has proven only for the art sites in Piaui State, where the name Itaparica is not in use. To the best of our knowledge, the engravings have never been dated. In the same article, in respect of chronological evidence Schmitz says (1987: 64): 'Between about 11,000 and 8,500 before the present, unifacial blade industries, in which endscrapers predominated, constituted a widespread tradition or horizon...'. We, however, have no industries on blades: those we have encountered in the period 11,000 to 8,500 were a small minority, and only rarely retouched. Moreover, endscrapers were not dominant. For the whole of Brazil we know of no technical complex which would merit the designation 'unifacial blade industries'. This is one more case of the tendency to define a complex by its most striking elements, the fine pieces. These simplistic labels hide the reality of great cultural complexity (cf. Hallam 1977). Then again, the reconstruction of the palaeoclimate presented by Schmitz (1987: 55,60, 71) is not substantiated. No pollen analyses are cited, nor any studies of palaeofauna as indicators of vegetation, and consequently of climate. The author continues (p. 59) 'The absence of gregarious animals (bison, horse, guanaco, etc.), which could support a specialized hunting economy, led to the development of a generalized hunting and gathering subsistence on the planalto dominated by parkland.' This statement is incorrect since numerous sites in the north-east of Brazil have yielded abundant remains of megafauna, including mastodon, llama and horse (Guerin 1991). Although no dates have been obtained as yet, the associated lithic material indicates that this fauna disappeared relatively late. The concepts of 'specialized hunting economy' and 'generalized hunting and gathering subsistence' are in our view artificial partitions created in the industrial age.
We now turn to some points made by Lynch (1990: 20-1). The author voices concern that the site lies 'at the level of the modern flood plain'. Since the rockshelter still exists, it can be verified that Pedra Furada is situated more than 19 metres above the immense plain surrounding the São Francisco river. This is an important point, since this is not a narrow valley subject to flooding. The sites are set into the cuesta front of the sedimentary basin which encompasses the plain, and on the east this is open to the Atlantic, some 1,200 km away. One can thus be quite sure that the waterlevel has never reached the height of the rockshelter. The watercourses which transported cobbles down from the plateau are found at the two ends of the great shelter, which is more than 70 metres long. We have considered in our analyses only the material coming from the protected area. Lynch is concerned that we have taken charcoal samples in disturbed areas, 'including parts ... in the stream channel itself, labelled "actual torrent's passage"'. Our plan, however, refers to a present-day watercourse which involves only one part of the site. It traverses only the upper layers in the eastern part. The plan shows the surface contours of the site before excavation began, and one should stress that the Pleistocene layers were four metres down, sealed in by a rockfall. The charcoal collected from the layer underlying this stream evidence was sampled in order to date the event responsible for creating the flow. It is extremely important, of course, to verify the entire complex of events, whether they are of natural or human origin, and one would not be able to reconstruct the geomorphological history of the site, if one were restricted to taking radiocarbon samples linked with human activity. Lynch also refers to photographs of Pedra Furada showing layers of stream-deposited sediments. We published these in a spirit of precision, so as to illustrate clearly the differences between them and the layers under the overhang of the rockshelter. Here - and this can be verified on site - the deposits consist only of sand and fine gravel, derived from the moderately coarse sandstone which is the country rock forming the rockshelter.
Nature of the lithic industry
A further question on early sites has been the status of the artefacts. Lynch doubts whether the lithic pieces associated with the early dates are of human origin (p. 21):
"these (are) crude artifacts. . . and numerous archaeologists and flintknappers, some of them with considerable Old World experience, including Bryan Fagan and myself, found it unconvincing." One wonders why early inhabitants would make use of these difficult raw materials if cryptocrystalline silica rocks were so easily available to later Archaic peoples.
In Lynch's view, the humans of the Pleistocene would have been very unlikely to have used quartz and quartzite, if they had access to flint, which was used from about 12,000 years ago. At Pedra Furada, however, as well as at other sites in the region of São Raimundo Nonato, the Holocene levels have yielded quartz and quarzite tools of the kind regarded by Lynch as 'crude artifacts'. But as these have been found in association with flint artifacts, nobody has called their anthropogenic nature into doubt.
Equally difficult to explain would be pottery using peoples, who are predominant in the region from about 3,000 years before the present, and who used exclusively quartz and quartzite for making tools, although they used jade for exquisite ornaments. As a further example, the inhabitants of some shell middens on the Brazilian coast were working in quartz at 5,000 years before the present.
As for the flint knappers, we would like the opportunity to show them certain specimens which have been made in these 'difficult raw materials'. Experiment enables us to understand certain parts of the 'operational chain' , but we will never have the same facility as an individual who has been knapping from childhood, and who does not have other techniques at his disposal. Technical competence is not acquired as easily as one might think, and the stone age knapper will use his hands and arms quite differently from a professor of archaeology.
In the case of Pedra Furada the work being carried out by Fabio Parenti at present will provide more precise answers, but we can state definitely now that there are retouched pieces. We agree with Butzer (1988) who suggests that, even if the pieces were naturally formed, the stone material has been carried by humans, since we have found cobbles, fragments flakes and retouched pieces in parts of the abri where they could not possibly have arrived by natural means.
Another alleged problem (p. 21) is that we have found no wooden or bone tools. This observation could be seen to increase doubts about the human manufacture of the stone industry, since in the classical scheme for this period, one ought always to find a stone industry associated with bone or wood tools. At Piaui we have never found any of these, even in the Holocene levels. On this point, Guidon recalls the advice of a great master of archaeology, Andre Leroi-Gourhan:
'Carry on excavating: sooner or later excavation resolves problems'.
Hearths and bushfires
Many hearths have been recorded and dated at Pedra Furada (cf. Guidon and Delibrias 1986), but these have also raised doubts. Lynch (1990: 21) writes 'it seems quite possible that these resulted from natural brush fires in the surrounding semi desert caatinga'. We do not accept this, since in that case:
- we should find charcoal scattered in layers, and not concentrated in the centre of the hearth arrangements;
- the quantity of charcoal should have been greater on the talus side than under the less-vegetated abri;
- patches of charcoal should have been found in the stratigraphy of the plain, since it would have been impossible for wind and water to have collected charcoal and placed it systematically and exclusively in small heaps inside the structures.
In relation to the critique which has been made of the hearth arrangements (foyers) at Pedra Furada we emphasize that they were made from blocks and cobbles, and that these cobbles could not have fallen naturally where they were found. The charcoal exposed existed only inside the structures.
Lynch attempts to link the dated charcoal with caatinga fires. In the present-day the site area of Pedra Furada is covered with forest vegetation. The caatinga covers the plain and the lower part of the talus. Contrary to what one might imagine, the trees and shrubs of the primary caatinga consist of very hard wood which burns only with difficulty. Some of these cannot even be used for firewood, and one has to select particular kinds for making a fire. When agriculturalists practise fire-clearing, the fire only takes in cut and dried trees, and does not survive more than 3 metres around. It takes hold only in secondary caatinga, resulting in bush-clearing in areas where shrubs and low growth are dominant. A further reason for rejecting the link between the charcoal and caatinga fires is the quite different nature of the Pleistocene vegetation cover, as noted above. Lynch is also concerned by the possibility of bioturbation by animals in the archaeological layers. This factor cannot be applied to the Pleistocene levels on this site, since they were protected from animal activities by a screen of boulders from the rockfalls.
Only the Holocene levels have suffered some disturbance, which can be attributed to an armadillo (thet tatouay). At Toca do Sitio do Meio, Lynch mentions 'badly disturbed contexts' and a date of over 40,000 before the present. In fact, the oldest date obtained for the site is 14,300 ± 400 before the present (GIF-5399). Although the Holocene levels have been disturbed by modern activity on the site, the Pleistocene levels are sealed, like those at Pedra Furada, by a great rockfall (see above). In relation to a third site, Toca do Caldeirao dos Rodrigues, Lynch considers that the charcoal is the result of natural fires, because we stated that the date of 18,000 before the present obtained for the site was not associated with a lithic industry, but we have indicated the presence of hearths (Guidon and Delibrias 1985). Carbon contamination has also been invoked to explain the old dates. The three rockshelters which have yielded dates older than 12,000 before the present are, however, sited in the sandstone cuesta, where it is impossible for the charcoal to have been contaminated by ancient carbon, for the simple reason that there is no carbon in the geological formations of the region. The only possibility of contamination, if there were any, would be from the humic acids of groundwater, or from roots, factors which could only tend to make the dates younger (Delibrias, pers. comm.).
A way forward
We have attempted to provide answers to certain doubts expressed about the interpretations in our work carried out in south-east Piaui. It is fair to stress that current theory about the peopling of the Americas is only a working hypothesis, based on conjectures rather than on facts. Reworking of the hypothesis is therefore necessary whenever new evidence indicates that it does not correspond with present realities. This procedure is the controlling rule of all scientific research. Often, one can sense the wish to reproduce in America a model derived from the Old World, where prehistoric people must be moulded to the needs of archaeological theories. We think, on the contrary, that archaeologists should build their models on the basis of the facts available to them. Many archaeologists could benefit from the article of Hallam (1977) concerning Australia. For an archaeology of the peopling of the Americas to progress, it must similarly free itself from Old World models. When one classifies a tool, for example a sidescraper (racloir), the critical judgement is based on the edge angle, and not on the fact that the piece in question can be identified as one of the types on Bordes' list, or some other Old World typology. These names are not satisfactory, and are used by default because there is a need for some common language, but the typology of the New World ought to free itself completely from this influence, and be reviewed in its entirety. It would be helpful if we could rise above the present state of controversy about New World chronologies, so as to establish an entente between the different currents of thought. It is unfortunate, for example, that authors, who doubt the discoveries made at Piaui have not visited the sites. Working parties, meetings of specialists on site, and formal debates, should take place regularly if we are to establish an agreed basis for evaluating evidence. It would be constructive for American prehistory if we could seek out a consensus upon the value of the factual material which accumulates year by. Then, on the basis of the evidence which we now possess, new theoretical propositions could be set forward.
Ecole des Hautes Etudes en Sciences Sociales
Butzer, K. W. 1988. "A marginality' model to explain major spatial and temporal gaps in the Old and New World Pleistocene settlement records." Geoarchaeology, 3: 193-203.
Delibrias, G., Guidon, N. and Parenti, F. 1988. "The Toca do Boqueirão do Sitio da Pedro Furada: stratigraphy and chronology." In Early Man in the Southern Hemisphere, supplement to Archaeometry: Australasian Studies 1988.
Guerin, C. 1991. "La faune de vertebres du Pleistocene superieur de l'aire archeologique de São Raimundo Nonato (Piaui, Brésil)." Comptes rendus de l'Academie des Sciences (Paris), 312, Series II: 567-72.
Guidon, N. and Delibrias, G. 1985. "Inventaire des sites sud-Americaines anterieurs a 12,000 ans." L'Anthropoloqie, 89: 385-407.
Guidon, N. and Delibrias, G. 1986. "Carbon-14 dates point to man in the Americas 32,000 years ago." Nature, 321: 769-71.
Guthrie, R. D. 1984. "The evidence for Middle-Wisconsin peopling of Beringia: an evaluation." Quaternary Research, 22: 231-41.
Hallam, S. J. 1977. "The relevance of Old World archaeology to the first entry of man into the New World: colonization seen from the Antipodes." Quaternary Research, 8: 128-48.
Lynch, T. F. 1990. "Glacial-age man in South America? A critical review." American Antiquity, 55 (1): 12-36.
Parenti, F. 1991. "Deep in the South American past - Pedra Furada and Brazilian prehistory." In: Ice Age Peoples of Central and South America (eds R. Bonnichsen and T. Dillehay). Austin: Texas University Press.
Schmitz, P. I. 1987. "Prehistoric hunters and gatherers of Brazil." Journal of World Prehistory, 1: 53-126.
Addendum 2003 The article reproduced above was published in 1991 - but
it is not outdated! Niède Guidon and Elliany S. La Salvia (
Fundação Museu do Homem Americano, Piaui), have published "Some Evidence of a Date of the First
Humans to Arrive in Brazil" This highly technical article on dating with
thermoluminescence comes to the following conclusion: From the present work we can conclude that the calcite
was formed on the rockwall paintings at least about
36,000 years ago. See also in this context - the Pedra
Furada archaeological site in northeastern Brazil - the Monte
Verde archaeological site in Chile
Shiegueo Watanabe, Walter Elias Feria Ayta, and Henrique Hamaguchi (Instituto de Fisica, São Paulo),
Silvia Maranca (Museo de Arqueologia e Ethnologia, Universidade de São Paulo), and
Oswaldo Baffa Filho (Dep. Fisica e Matemática, Universidade de São Paulo)
in the Journal of Archaeoleogical Science, 2003, vol. 30:351-354
Hence, human beings that painted them did it before 36,000 years ago. This value reinforces results obtained by archaeologists
at Serra da Capivara (e.g. Pedra Furada, ed.) using C14 method.
The article reproduced above was published in 1991 - but it is not outdated!
Niède Guidon and Elliany S. La Salvia (
Fundação Museu do Homem Americano, Piaui),
have published "Some Evidence of a Date of the First
Humans to Arrive in Brazil"
This highly technical article on dating with thermoluminescence comes to the following conclusion:
From the present work we can conclude that the calcite
was formed on the rockwall paintings at least about
36,000 years ago.
See also in this context
- the Pedra Furada archaeological site in northeastern Brazil
- the Monte Verde archaeological site in Chile
Last changed 30 October 2007