Saturday 9 April 2016

Pre-Clovis Archaeological Sites of the Americas 7: Santa Elina Rock Shelter, Mato Grosso, Brazil 25,000BP


As readers of this blog must be aware, I am quite fascinated by the peopling of the Americas. I often look at websites which take an unbiased view of the possible evidence of the earlier claims of man in the Americas. Of particular interest is the Center for the Study of the First Americans (CSFA). A marvellous resource is their archive of the publications Mammoth Trumpet and Current Research in the Pleistocene. They are often a goldmine of information about less well known archaeological sites. Recently, while reading a back issue (1) I came across information on a site I have long been interested in: Santa Elina rock shelter in Brazil.

The rock shelter was first discovered due to the thousands of both geometric and human figures, such as this one from Vialou (6):
 
 
 


One of the 1000’s of human figures and geometric designs up to ca. 10,000 BP painted at Santa Elina rock shelter from Vialou (6), original caption: Rock Shelter, Santa Elina: Indian painting.

Here’s the information from the Mammoth Trumpet article:
“Another Brazilian site, the Santa Elina rockshelter, located in central Mato Grosso state, has produced early radiocarbon and thermoluminescence dates on stratigraphic levels containing remains of Glossotherium (a giant ground sloth) and associated lithic artifacts. This large limestone rockshelter is currently under excavation by Agueda and Denis Vilhena Vialou; and only preliminary reports are presently available (2).
To date, three major units have been identified in the known stratigraphic record. Unit III, a 60-cm-thick sandy deposit with rock rubble, is subdivided into four subzones. Bones of one individual Glossotherium, together with thousands of osteoderms (small spherical bones within the skin of a ground sloth), were found clustered within a limited area in subzone III-4/3, in association with 27 retouched tabular pieces and percussion flakes of limestone or flint. Notched or denticulate tools are common in the assemblage, and some pieces show use wear. There are also ca. 50 unmodified percussion flakes. Also found on this level were several small quartz crystals and a hematite fragment. Two of the sloth osteoderms feature smooth circular perforations, and the faces of one of these show abrasion.
Radiocarbon dates of 22,500 ± 500 RCYBP and 23,320 ± 1000 RCYBP have been obtained on wood recovered by flotation from stratigraphic subzone III-3/2, just above the level of the lithic artifacts and sloth remains in subzone III-4. A sample of osteoderms from subzone III-4 was dated at 27,000 ± 2000 yr B.P. by the
uranium/thorium method. Further AMS dating of charcoal and OSL dates on sandy sediments in subzone III-4 are reported to range around 25,000 years ago.
The III-4 subzone is at a depth of ca. 3 m within the rockshelter fill. One meter above, separated by virtually sterile deposits, is a younger occupation level (in Unit II-2) with Glossotherium bones and ca. 200 lithic artifacts. This level has produced a radiocarbon date of 10,010 ± 60 RCYBP on charcoal from a hearth. Research at the Santa Elina rockshelter continues, so we must await final results. As of the 2003 report, bedrock had not been reached.”

Location:

About 100km north west of Cuiabá the capital of Matto Grosso state.
 
 
Location of Santa Elina rock shelter within South America. Left hand map of the continent adapted from Cione (3) showing that surrounding region at the height of the Last Glacial Maxima (LGM at ca. 20Kya BP) was a mosaic of open forest and savanna. Right hand map adapted from Bachelet (4), showing similar current vegetation known as cerrado.
Environment
According to Cione at al. (3), the habitat in the region of the central Matto Grosso was similar to that of the present if a little cooler around the height of the LGM. Today the habitat in the area of Santa Elina rock shelter is described by Bachelet and Scheel-Ybert (5) as “This region is dominated by the Cerrado biome, comprising wooded savannas (cerrado stricto sensu, veredas), park and gramineous-woody savannas (campo sujo, campo rupestre, campo limpo), and forest formations (riparian forest, dry forests, Cerradão). The local landscape is defined by deciduous and semideciduous forests, cerrado, riparian forests, and anthropogenic areas (deforested areas, pastures) (Ceccantini, 2005). The climate is tropical hot (Aw in Köppen classification), with a dry season of 4-5 months from May to September; mean temperature is 250C, with maxima over 400C in the summer; mean precipitation is around 1700 mm.”



 
Cerrado types (Portugese) from Ecel Capoeira blog (7).
Santa Elina excavation details
The main publication about the Santa Elina rock shelter is that of Vialou (8), who excavated the site between 1985 and 2005. Unfortunately he published his discoveries in a monograph, in book form, in Portuguese and thus is unavailable to me. Unlike the situation with many other American archaeological sites there are few papers by about this site available on the internet. Thus details about the excavation must therefore be gleaned from translations of French papers by Vialou and Vilhena Vialou or from secondary sources.
 
 

Excavations at Santa Elina rock shelter. The cave is ca. 60 m long and situated in the Serra das Araras at the base of a  Precambrian limestone bed of dimensions 40 to 50 km wide, up to 800 m high and 500 km long. The cave is tilted in both longitudinal and vertical axes as shown in Vialou (6), original caption: Fig 1. Rock Shelter, Santa Elina: long stratigraphic sequence, 25 000 years to 2000 years BP.

 
 
The discoveries were summarised by Bachelet and Scheel-Ybert (5) thus:
“Three main archaeological assemblages were identified in the stratigraphy: The upper archaeological layers (assemblage I), containing the more recent occupations dated between 2000 and 6000 BP, are characterized by the exceptional preservation of many plant remains. The anthropogenic sediments, fine and powdery, are formed primarily of ash. The site shows habitation structures, numerous combustion structures, rich in charcoal and sometimes containing fruits and other plant remains, food remains, lithics, and adornments. Fruits, seeds, braided fibres and ropes, artefacts such as sandals, penian sheaths, and packages, wooden stakes, wood, charcoal, and even leaves abound. Lithics and pigments are very common (Vilhena Vialou, 2005).
An intermediate archaeological layer (assemblage II) was dated between 6000 and 10,000 BP, when several human groups are thought to have succeeded each other in the shelter. In these levels, sediments are sandy and non-charred plant remains are rare. The material culture is characterized by lithic material, extinct fauna remains of Glossotherium lettsomi, several hearths, and charcoal (Vilhena Vialou, 2005). The lower archaeological levels (assemblage III), dated to the Late Pleistocene (22,500 ± 500 BP), present are many megafauna remains of G. lettsomi, frequently identified in direct association with lithic material. The sediments are sandy and stony, and plant remains are scarce. Only lithics and a few fragments of charcoal dispersed in the sediments were retrieved (Vilhena Vialou, 2003, 2005).”
A useful stratigraphic diagram is also included in their paper:
 
Stratigraphic profile of Santa Elina from Bachelet and Scheel-Ybert (5), note caption for level III4 ‘couche a megafaune’ dates to 27,000BP - at variance with the text giving a date of 22,500BP. Original caption reads: Fig. 3. Schematic stratigraphic section of the square 29-ABCD in Santa Elina rock shelter, representing the three archaeological assemblages: “assemblage I” (2000-6000 yrs BP) top gray; “assemblage II” (6000-10000 yrs BP) in white; “assemblage III” (around 25000 yrs BP) bottom gray (from Benabdelhadi, 2005).
Vilhena Vialou and Vialou on the archaeological finds made:
“For various occupation floors uncovered at the base of the upper sequence, dated by 14C between 9,400 and 10,120 years BP, is associated with a well characterized lithic industry: many breakdown products (cores, flakes, cassons), mainly of silicified limestone but also of flint and sandstone, all rocks encountered near the shelter, within a few hundred meters; some quartz fragments, material taken in small outcrops visible in the mouth of the canyon, about 2 km from the site.  The tools consist of summarily retouched pieces and notches, cruder than at higher levels, also produced little except some remarkable pieces such as large projectile points (Vilhena Vialou and Vialou 1994 Vilhena Vialou et al. 1999; Vilhena Vialou 2005; Aubry 2005).
In this large occupation floor of 30 m2 extent, lithic pieces are clearly associated with many skeletal remains of a giant sloth (Glossotherium Letsomii), a species of the South American megafauna that became extinct at the end of Pleistocene.
The lower sedimentary layer of the chrono-stratigraphic sequence was also stripped of 30m2 between 2.80 and 3.50 m depth from the current surface.  The anthropogenic remains are in a compacted sediment amongst large weathered limestone blocks.  In places, a thin slightly greyish film contains fine ash and micro-fragments of coals.
The level of human occupation floor contained about 200 lithic pieces and, in abundance, the bones of Glossotherium.
 

 
Lithics from the lowest human occupation levels at Santa Elina rock shelter. Image source Vialou (8).
Osteoderms (dermal bones of 1 to 4 cm in length), revealed the number of 5000, were repeatedly grouped into small piles by prehistoric man.  Some are broken and two were redesigned conclusively by abrasion of their natural surfaces; these may be ornamental elements.  About 200 bones mostly, split are anatomically identified: ribs, vertebrae, maxilla and mandible.  They show that only the front part of a single animal was introduced into the occupation.  The animal died naturally or was killed by hunters, or was carrion was brought into the shelter (Vilhena Vialou et al 1995. Vilhena Vialou 1997-1998 Vilhena Vialou 2003 and 2005; Cartelle 2005).
 
Glossotherium osteoderm [Glossotherium chapadmalense] from López-Mendoza (9). Original caption: Figure 7a. : An undamaged dermal bone from Baño Nuevo-1;
 
The three dating methods have used at the site: Uranium-Thorium on osteoderms of Glossotherium, optical stimulated luminescence (OSL) on the quartz grains of sediment coating the archaeological and faunal material (with dosimeters placed in the layer section), accelerator mass spectrometry (AMS) from micro-charcoal collected in the layer.  These three methods have provided dating around 25,000 years BP.  A Uranium-Thorium dating attempted on osteoderms collected in the upper  archaeological hearths of the upper layers has provided a date of around 13,000 years, corresponding to 10,000 years BP obtained by 14C dating.  Similarly, OSL dating on Glossotherium remains of the sandy levels inserted between the two occupations gave interim dates.  The intercalibration of the three methods (both being the lower limit of their validity) gives a result that further strengthens the remarkable dating of anthropogenic deep level, the oldest now obtained in archaeological contexts is stratigraphically well established ( Falguères 2005 Feathers 2005 Fontugne, Hatté and Noury ​​2005 Valladas 2005).”
 
Some authors such as Bueno, et al. (10), comment on the lithic assemblage from Santa Elina:
“During the 10th 14C millennium BP, the Itaparica Tradition reaches its greatest spatial extent in the cerrado and caatinga biomes of the Central Plateau and Northeast. On the Central Brazilian Plateau there are at least 23 known occupation events, fairly evenly distributed across that time range. With three exceptions e Santa Elina, Morro Furado and Boqueirão do Soberbo - all the occupied sites can be associated with the Itaparica Tradition.
..There is one site in this period in Central Brazil that we cannot assign to the Itaparica Tradition: Santa Elina, MT. The site is a limestone rockshelter, located at Serra das Araras, 100km northeast from Cuiabá, MT. Based on a series of different samples that have been dated by different analytical methods, the researchers responsible for work at this site have defined four main periods of occupation, extending from 25,000 14C BP until the colonial period (Vialou, 2005). During their second period, between 10,000 and 7000 14C BP, one of the most important aspects of the lithic assemblages is the virtual absence of formal artefacts. In all levels related to this period a lithic assemblage predominates with simple and cortical flakes made of limestone, chert and quartz. These raw materials are all found in the vicinity of the rockshelter and the flaked limestone is the same as the rock of the rockshelter. Most of the flakes were used without retouch; when it is present, it is frequently marginal, producing small and abrupt edges. Beside the absence of retouching and the short extension of the edge, most of the flakes are large and wide, offering very robust cutting edges (Vialou, 2005).”
 
Verdict:
1. This site is little known outside Brazil and France due to the dearth of published material in English. The main source of detail is Vialou 2005, a monograph in book form published in Portuguese. Some review article has been published in French. Consequently it is a little hard to assess the the quality of the evidence to support the dating of the site to 25,000BP.
2. Secondary sources largely lend support to the site as being occupied by humans who utilised Giant Ground Sloth for food at 25,000BP.
3. The three independent lines of dating strongly support each other lending weight to point 2 above.
4. The lithic assemblage is unusual. It seems more primitive than the well-known and recorded Itaparica tradition. This fits well with the early dates obtained by the investigators of the site: If the site is early it should have primitive lithics.
5. The lithic style of tool production changed little over a long period of time. A similar phenomena has been noted at similarly controversially early dated site such as Pedra Furada.
6. If the site really IS as old as 25,000BP who were the people that occupied it and why did their lithic toolkit change so little over thousands of years? Perhaps they represent an earlier wave of migration into the Americas by archaic Homo sapiens?
 
See Here for a post on human migration rate and the possible early entry date into the Americas.
 
 
 

 

References
1.  Gruhn, R. 2007. The Earliest Reported Archaeological Sites in South America.
The Mammoth Trumpetv 22/1, Center for the Study of the First Americans Department of Anthropology, Texas A&M University.
 
2. Where the South Winds Blow, the 2003 CSFA publication edited by Laura Miotti, Mónica Salemme, and Nora Flegenheimer).
 
3. Chione, A.L. et al. 2010. Did Humans Cause the Late Pleistocene-Early Holocene Mammalian Extinctions in South America in a Context of Shrinking Open Areas? In American Megafaunal Extinctions at the End of the Pleistocene, G. Haynes (ed). Springer Netherlands, 2010
 
4. Bachelet, C. 2014. Pré-História no Cerrado: Análises antracologicas dos abrigos de Santa Elina e da Cidade de Pedra (Mato Grosso) [Prehistory in the Cerrado: Anthracological analysis of Santa Elina and Cidade de Pedra rocks shelters (Mato Grosso)] FRONTEIRAS: Journal of Social, Technological and Environmental Science v.3, n.2, jul.-dez. 2014, p.96-110.
 
5. Bachelet, C and R Scheel-Ybert Landscape and firewood selection in the Santa Elina rock shelter (Mato Grosso, Brazil) during the Holocene. Quaternary International xxx (2015) 1-9 · JANUARY 2015. DOI: 10.1016/j.quaint.2015.12.019
 
6. Àgueda Vilhena Vialou et Denis Vialou, « Peuplements préhistoriques au Brésil », Les nouvelles de l'archéologie [En ligne], 111/112 | 2008, mis en ligne le 15 juin 2011, consulté le 05 avril 2016. URL : http://nda.revues.org/214  ; DOI : 10.4000/nda.214
 
 
8. Vilhena Vialou, A., 2005. Habitat e cronoestratigrafia. In: Vilhena-Vialou, A. (Ed.),
Pre-historia do Mato Grosso, vol. 1. Santa Elina. Edusp, S~ao Paulo, pp. 87e102.
 
9. López-Mendoza, Patricio and  Mena-Larraín, Francisco. 2011.
Extinct ground sloth dermal bones and their role in the taphonomic research of caves: the case of Baño Nuevo-1 (Andean Central Patagonia, Chile)
Revista Mexicana de Ciencias Geológicas, vol. 28, núm. 3, pp. 519-532 Universidad Nacional Autónoma de México Querétaro, México
 
10. Bueno, L., et al., The Late Pleistocene/Early Holocene archaeological record in Brazil: A geo-referenced database, Quaternary International (2013), http://dx.doi.org/10.1016/j.quaint.2013.03.042
 

 

2 comments:

  1. Dear Vonda, glad you enjoyed it. There are a lot of other very old sites, particularly in South America, that I have yet to write posts about. I hope to do so in the future. NeilB

    ReplyDelete