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The peoples of Lagoa Santa

Human burial sites in Minas Gerais reveal a succession of customs from 10,000 to 8,000 years ago

Lapa do Santo, a rockshelter in the midst of the Cerrado savannah, appears to have been an important center for rituals associated with death

Mauricio de Paiva Lapa do Santo, a rockshelter in the midst of the Cerrado savannah, appears to have been an important center for rituals associated with deathMauricio de Paiva

An opening in the face of a steep cliff in the midst of the Cerrado savannah in the Lagoa Santa region of the Brazilian state of Minas Gerais has presented archeologists, biologists and anthropologists with a surprising revelation. The cave, a rockshelter known as Lapa do Santo, was once an important center for funerary rituals, as revealed by excavations described in an article currently in production for the journal Antiquity, one of the most prominent publications in that field. Complex burial patterns that feature dismembered corpses and arrangement according to precise rules reveal a succession of very distinct cultures during a period that had been regarded as homogeneous, around 10,000 years ago. “The greatest benefit was in discovering these cultural changes over time, which for some reason no one had noted before,” says Brazilian archeologist André Strauss, a visiting professor at the University of Tübingen in Germany, doctoral candidate at that country’s Max Planck Institute, and principal author of the article. The study moves beyond death and presents a look at who these people were and how they lived.

Strauss felt that there was something special in that place during his first year in the geology program at the University of São Paulo (USP), when he went on his first field expedition in 2005 as an intern for bioanthropologist Walter Neves of USP Biosciences Institute (IB-USP). “I was at the bottom of a two-meter-deep trench, digging and sifting through what I found.” It was from that spot that Strauss became fascinated with what there was yet to discover there and wanted to do something other than focus on skull measurements and the search for signs of coexistence with large animals known as megafauna. That was the focus of the research conducted back in the 19th century, when Danish naturalist Peter Lund discovered human bones associated with large animals in a cave in Lagoa Santa, launching a tradition of excavation that made it one of the oldest archeological regions in Brazil. Five years later, during his master’s studies under Neves, Strauss saw some order in the apparent confusion at the site: what appeared to be a jumble of bones with no significance did, in fact, follow a pattern. “It’s difficult to perceive the subtleties. The graves are very complex.”

Arqueologia_Mapa_247“This was possible because Walter reversed the usual order of the field procedures,” Strauss notes. Brazilian archeology, he says, generally focuses on artifacts, and only calls in specialists in human fossils when bones are found. “Many skeletons are damaged in the process.” Neves has been analyzing human evolution in the Americas since 1988, conducting a case study in this region. In his projects, bioanthropologists coordinate the excavation and document everything they find, and rely on specialists to analyze the artifacts—in the case of Lapa do Santo, stone fragments and tools made of bone, such as spatulas, chisels and, on rare occasions, fishhooks.

In the cave, whose walls are decorated with relief drawings indicative of fertility rituals (phallic images), the findings were striking. Strauss, Neves and their colleagues identified three distinct periods of human occupation, the oldest from 12,700 to 11,700 years ago. Between 2001 and 2009, they exhumed and analyzed 26 human graves dating back to approximately 10,500 and 8,000 years ago, which revealed a variety of funerary practices never before discovered in the lowlands of South America. These practices were described in the article in Antiquity and another article of which André Strauss was the sole author, published in the January-April 2016 issue of Boletim do Museu Paraense Emílio Goeldi.

“There were highly sophisticated funerary practices in the Andes,” says Neves, “but the Chilean mummies previously studied are more recent than the material from Lapa do Santo”. Another distinction is that the cave in Minas Gerais contains no funerary offerings, while the customary practice of hunter-gatherers was to bury the dead along with at least their belongings. “The complexity of the practices discovered at Lapa do Santo resides not in the objects, but in a high degree of manipulation of the body and skeleton, in a very sophisticated manner,” says the USP professor.

Arqueologia_247

Funerary rituals
The oldest burial pattern, dating back to between 10,600 and 9,700 years ago, was described on the basis of a man and a child approximately five years old, both buried intact. The child was placed in a seated position, with the legs folded and the knees close to the head. The separated jaw, looking as if the mouth were open, indicates that the pit was not completely filled in.

The removal of body parts after death characterizes the following period, between 9,600 and 9,400 years ago. This assemblage is represented in seven burial sites, plus a few disarticulated bones, and is described as the second pattern. Some of the skeletons were articulated, but with parts missing. One striking case was that of a man whose head appeared to have been removed hours after death and buried with his two hands (also severed, as indicated by cut marks on the wrist bones) covering his face—one pointing upward and the other downward, as Strauss and colleagues described in 2015 in the journal PLOS ONE (see news item at bit.ly/DecapMG).

Other skeletons were completely dismembered and arranged in bundles, indicating that the bones were stored together, perhaps wrapped up, and buried only after flesh removal and drying. Many of the isolated bones had also undergone changes such as burning, cutting, application of red pigment and removal of teeth. In some cases, the bones of one or two children were combined with the skull of an adult, or vice-versa, in a manner suggesting very precise rules for how the burial should be carried out. Removed teeth were also buried with the mortal remains of another person.

Skull with teeth removed

Mauricio de Paiva Skull with teeth removedMauricio de Paiva

The third burial pattern, dating to 8,600 to 8,200 years ago, involves nine heaps of bones arranged completely disarticulated in circular pits 30 to 40 centimeters in diameter and only 20 centimeters deep. Each completely filled-in pit contained a single individual. In the case of adults, the long bones were generally broken after death, and were only then able to fit into the small tombs.

Even with so many cases of dismemberment, there are no signs that violence in life was a common practice. “We read the bones; everything is recorded in them,” Strauss says. And they show very low levels of healed fractures that would indicate they had occurred while the person was alive. Generally speaking, Strauss believes that the findings represent a paradigm shift in how we view human habitation in the area during that period—the early Holocene. “For a long time, the big question was whether Luzia was the oldest skull in the Americas and whether it resembled Africans,” he says, referring to the 11,000-year-old skull described by Neves, which redefined the way human occupation in the region should be viewed. “We now know that there was not just one Luzia people in Lagoa Santa; it was a succession of peoples who inhabited the region with very clear-cut cultural changes.” In fact, it was a period of about 5,000 years—enough time for very diverse populations, even if they were to some extent descended from one another.

DNA studies are soon expected to start yielding results and providing some answers about how these groups succeeded one another and what the relationship was between them. “Cranial morphology shows that they had the same “general architecture,” Walter Neves notes. There is continual variation in this large group, which he defines as Paleoamerican. According to his theory, which posits that two distinct migrations gave rise to the inhabitants of America, the first people with Asiatic features likely arrived there about 7,000 years ago—though there are no human remains in Lagoa Santa that date back to between 7,000 and 2,000 years.  Nonetheless, the existing clues from there and other sites are gradually refining the hypothesis. “I thought the second migratory group had replaced the Luzia people,” he admits. “But today we have very strong evidence that this morphology survived intact until the 19th century.” Such is the case, for example, for the Botocudo Indians, who were decimated during the colonial period, according to skulls stored at the National Museum of Brazil, as maintained by Strauss, Neves and colleagues in a paper published in 2015 in the American Journal of Physical Anthropology.

Fishhooks made of bone

Mauricio de Paiva Fishhooks made of boneMauricio de Paiva

Life practices
Since he began his PhD studies in 2011, Strauss has coordinated the work at Lapa do Santo, with German funding. The archeological riches there sustain the two countries’ interest in collaborative efforts, which include partnerships for genetic studies. The Brazilian counterpart on the project is Walter Neves, whose Laboratory for Human Evolutionary and Ecological Studies (LEEEH) receives all materials collected on the expeditions. No remnants of ceramics have been found in recent years—a strong indication that these were hunter-gatherers who lived there part-time, rather than farmers, thus corroborating established thought. They hunted for fish, lizards, rodents, armadillos, wild pigs and small deer, all of which they carried back to the cave intact. There was no evidence of larger animals such as tapirs or the enormous mammals of the megafauna group, which was believed to have been associated with the humans of Lagoa Santa ever since Peter Lund found an association in another cave in the region, between 1835 and 1844. Not always the case, it would seem.

“They even ate rock cavy,” Neves exclaims, referring to rodents slightly larger than a guinea pig. In his opinion, there is no diet more precarious than these animals, which indicates that the population groups in Lagoa Santa had no better sources of protein available to them, and existed at a borderline subsistence level. While this is only a theory, the scarcity of belongings at the burial sites may be an indication that there was no room for waste, and tools—such as fishhooks, of which only seven were found at Lapa do Santo—were a necessity of life. “Their time was devoted to facilitating the existence of the group,” Neves speculates. And by his estimates, they were large groups.

020_Arqueologia_03_247_altaAndré Strauss / University of TübingenTheir way of life may now be more well-delineated, but that conclusion also presents an enigma. Chemical analyses that reveal diet by quantifying carbon and nitrogen isotopes, carried out by Brazilian biologist Tiago Hermenegildo as a PhD student at the University of Cambridge, England, have shown that the inhabitants of the region ate many vegetables and supplemented their diet by hunting. Such high consumption of vegetables is unexpected for hunter-gatherers, especially with a diet rich in carbohydrates, as indicated by the large numbers of cavities in teeth found in the area.

Rodrigo Elias de Oliveira, a dentist and researcher in Neves’ group, has coauthored a paper with lead author Pedro Tótora da Glória, also of LEEEH, on dental health at Lapa do Santo. Their study is to be published in the journal Annals of the Brazilian Academy of Sciences. Elias, who has partnered with Strauss since 2006 in the excavations at Lapa do Santo, explains the discrepancies between the incidence of cavities they have observed and what has been documented for other hunter-gatherer populations, since Lagoa Santa is a tropical climate region with Cerrado savannah vegetation. “The other examples we have are from temperate climates,” he says. “Here the naturally available food—many types of fruit and tubers—can cause more cavities.” He is focusing on the fruit of the Brazilian pequi and cherry trees, still widely used today in the region, as a source of food at that time. These fruits are rich in carbohydrates, and carbonized fragments have been found at the Lagoa Santa sites.

Elias, who did his PhD research under Walter Neves and is now a postdoctoral researcher in periodontics at the USP School of Dentistry, brings to the project a detailed knowledge of teeth—which are abundant at archeological sites because their material is stronger than bone. “A tooth is like a capsule, and it turns out to be our time capsule, packed with information,” he says. He explains that bones renew themselves continuously, so one could say that a person replaces his skeleton every 10 years. The teeth of an adult, however, are evidence of the time in one’s life when the permanent teeth form. Elias hopes that isotopic studies currently underway in collaboration with Hermenegildo will help them to delve deeper into even such detailed dietary aspects as the types of plants the people ate, lifetime migratory movements, and how long children were breastfed. The dentist adds that the presence of strontium isotopes, as well as the shape of the femur, which responds to muscle activation, indicate that the people found at Lapa do Santo were natives of Lagoa Santa. “They had mobility, but they were not nomadic.”

021_Arqueologia_02_247_altaMauricio de Paiva Floor of ashes
The inference of intense human occupation arises from confirmation that there were many bonfires at Lapa do Santo. “They used fire all the time; they knew what they were doing,” says archeologist Ximena Villagran of USP’s Museum of Archeology and Ethnology (MAE). Her microscopic analyses of sediment from the cave revealed a large quantity of ashes up to a depth of one meter, as discussed in a paper published in the Journal of Archaeological Science in July 2016. The inhabitants of the region not only controlled fire, they apparently planned its use and stored decomposing wood. This level of detail is possible as a result of organic petrology analysis, a technique that recently came into use in archeology, and to which Villagran had access through her partnership with French geologist Bertrand Ligouis during a postdoctoral fellowship at the University of Tübingen, where he heads the Laboratory for Applied Organic Petrology.

Another cutting-edge technique used by Villagran was Fourier transform infrared spectroscopy (FTIR), normally used to analyze loose sediment. Villagran placed her samples on glass slides, which enabled her to investigate exactly why the sediment is composed of aggregates of several shades of yellow, orange and red. As she characterized the sediment inside and around the cave, it became clear that the ashes had been produced inside the rockshelter. She also identified termite mound fragments, indicating that the material was brought inside the cave for some reason. “Perhaps they used the fragments as hot stones for cooking or as an oven, like the ones the Xavante Indian groups used to make their maize cake,” she speculates. After this microscopic-scale revelation, it became apparent that the grasslands of Lagoa Santa were abundantly populated with termite mounds.

An enigma presented itself when Villagran confirmed that the dark red color she had observed in certain parts of the sediment would have required high temperatures, above 600 degrees Celsius (°C). In experiments in which she lit fires and inserted a long-stem thermometer into the flames, Villagran verified that the soil beneath the fire was not subjected to high temperatures. The explanation literally fell onto her head the second time she visited the archeological site. “I realized that sediment rains down from the rock wall above the entrance to the cave,” she says. If it were to fall directly onto a fire, these particles would encounter temperatures of 800°C to 1000°C.

020_Arqueologia_02_247_altaAdriano Gambarini As she analyzed the microstructure of the sediment around the burial sites, Villagran noted a continuity that had been disturbed at certain points, as if someone had dug to make a pit. She intends to continue conducting analyses so as to give a detailed description of how the burials were done. Strauss also wants to know whether the sophisticated funerary practices existed only in Lapa do Santo. He supports the idea that it was a more disseminated culture. “I went to look at the past publications, and the signs are there; they just needed that type of analysis,” says the archeologist, who wants to expand the studies to other regions of Brazil.

One limitation is that what has already been excavated cannot be recovered, unless the documentation was extremely meticulous. And until recently the records were insufficient, possibly due to lack of resources. “Doing an excavation is like reading a book and burning the pages,” says Strauss, who specialized in archeological documentation. He says that removing a grave takes 20 to 25 days, as the sediment is removed gradually while a three-dimensional model of the finds is created and everything is recorded using photography and video. Archeologists’ field notebooks, he says, should convey the information and observations in detail and should be public, not written like a personal diary. “That realization is still growing in Brazilian archeology.”

Between 2011 and the present, another 11 burial sites were exhumed, corroborating the patterns described earlier, and they are now being studied. The excavations continue at Lapa do Santo and promise to reveal even more layers of time and customs. According to American archeologist Kurt Rademaker, a professor at Northern Illinois University and an expert on hunter-gatherers, the work at Lagoa Santa, added to the work being done in the Andes region, is revealing a great cultural diversity. “Strauss and his interdisciplinary team are doing cutting-edge archeological science and enriching our knowledge about the physical appearance, ancestry and ways of life of ancient South Americans, particularly their highly interesting ritual practices,” he says. It is impossible to know what was going on in the heads of these ancient inhabitants of what is now Minas Gerais, but the team involved in the research is committed to putting together an approximate picture.

Project
Origins and microevolution of man in the Americas: a paleoanthropological approach (III) (nº 2004/01321-6); Grant Mechanism Research Grant – Thematic Project; Principal Investigator Walter Alves Neves (IB-USP); Investment R$2,032,930.19.

Scientific articles
STRAUSS, A. et al. Early Holocene funerary complexity in South America: The archaeological record of Lapa do Santo (east-central Brazil). Antiquity. In production.
DA-GLORIA, P. J. T. et al. Dental caries at Lapa do Santo, central-eastern Brazil: An Early Holocene archaeological site. Annals of the Brazilian Academy of Sciences. In production.
STRAUSS, A. et al. Os padrões de sepultamento do sítio arqueológico Lapa do Santo (Holoceno Inicial, Brasil). Boletim do Museu Paraense Emílio Goeldi. Ciências Humanas. V. 11, No. 1, p. 243-76. January-April 2016.
STRAUSS, A. et al. The oldest case of decapitation in the New World (Lapa do Santo, east-central Brazil). PLOS One. Sept. 2015.
STRAUSS, A. et al. The cranial morphology of the Botocudo Indians, Brazil. American Journal of Physical Anthropology. V. 157, No. 2, p. 202-16. June 2015.
VILLAGRAN, X. S. et al. Buried in ashes: Site formation processes at Lapa do Santo rockshelter, east-central Brazil. Journal of Archaelogical Science. Online. July 26, 2016.

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