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Surprisingly Healthy Teeth Write a New Chapter in Ancient History

Haagen Klaus studies the ancient and mysterious remains of societies along Peru’s northern coastal areas. A recent project has seen him racing against the clock in the modern-day town of Olmos to rescue skeletons from a looming construction project and the scathing rains of El Niño. Here, he presents the findings from his most recent field...

Very healthy teeth: oral biology and pathology is a reflection of diet, and the people of Olmos demonstrated excellent oral health, likely linked to a rather healthy and diverse diet.  Photo: H. Klaus.
Very healthy teeth: oral biology and pathology is structured strongly by long-term patterns of diet. The people of Olmos demonstrated excellent oral health likely linked to a rather high-quality and diverse diet. (Photo by Hagen Klaus)

Haagen Klaus studies the ancient and mysterious remains of societies along Peru’s northern coastal areas. A recent project has seen him racing against the clock in the modern-day town of Olmos to rescue skeletons from a looming construction project and the scathing rains of El Niño. Here, he presents the findings from his most recent field season. Read the previous posts here.

The Skeletons of Olmos, Part V: Surprising New Findings on Middle Sicán Civilization

If you recall from my first post, I described Peru’s ancient Middle Sicán state (A.D. 900-1100). The Middle Sicán culture was multi-ethnic, technologically precocious, and very hierarchical. A very significant gap of social and economic power separated an ultra-powerful leadership from those they ruled. Most of the non-elites appear to have been Muchik peoples—the descendants of the earlier Moche. The Olmos skeletons had the potential of answering key, unresolved questions about identity, social structure, and human biology within this historically pivotal civilization.

Who was living in these far northern reaches of Middle Sicán territory? Were they the bridge between the Lords of Sicán and Ecuador? Could they have been a colony of the mysterious Tallán peoples, or a far-flung enclave of Sicán citizens? Were these people allies or enemies of the Middle Sicán state?

Haagen Klaus gathering genetic information from inherited tooth size. Here, he is measuring the teeth of one of the Olmos individuals using a digital caliper.
Here I am, gathering genetic information for the study of inherited tooth sizes by measuring the teeth of one of the Olmos individuals using a digital caliper. (Photo courtesy Haagen Klaus)

Patterns in the Burials

The bioarchaeology of identity is a complex area of study, linking with many kinds of archaeological, skeletal, and behavioral evidence. In this case, one of the first clues we looked at involved burial patterns.

The bodies were all laid on their backs and were accompanied by modest offerings of ceramic vessels, including domestic cooking pots. A few people had bronze items buried with them. This is exactly the common burial pattern of the Muchik ethnic group—not the lavish, gold and silver-appointed shaft tombs of Sicán lords who were often buried in a seated and flexed (almost fetal-like) position.

Also, our initial study of inherited dental traits seems to show that the Olmos individuals were indistinguishable from the local population and were part of a common gene pool—not a group of foreign peoples with a different genetic origin.

Olmos Sector 2 Burial 11: Though living in the Middle Sicán era, this person, and the others interred in Olmos, were buried in a quintessential expression of the long-lived Muchik funerary tradition.  Photo: L. Peña, ASE.
Olmos Sector 2 Burial 11: Though living in the Middle Sicán era, this woman and the others interred in Olmos were buried in a quintessential expression of the long-lived ethnic Muchik funerary tradition. (Photo by L. Peña, ASE)

Along these lines, it would seem that we had found a far-flung community of Muchik commoners living in the northern reaches of Middle Sicán territory. There were no traces of Tallán cultural traits or anything else from southern Ecuador.

But were Muchik groups native to the area? Did Sicán administrators resettle this group (just as Inka public policy would do a few hundred years later)? Were they there to occupy the area and prevent territorial encroachment from the north? Only more archaeological studies can help answer such questions on the cultural history of Olmos.

A Biological Bombshell

Over the last 15 years, studies of nearly 500 skeletons a few colleagues and I conducted have shown that the systematic differences in wealth, power, and access to resources in Middle Sicán society were so significant that they structured very different lived experiences for the elites and commoners. These differences of lifestyles were in a very real sense written into their bones and teeth (read about it in an earlier post).

The skeletons of Middle Sicán elites indicate they lived very well. They ate diets of superior nutritional quality, had a lower prevalence of all skeletal pathological conditions, and physically undemanding lifestyles.

Non-elites, whom we have studied now from nearly a dozen sites, carried much greater burdens of infection, degenerative joint disease, anemia, and growth arrest in childhood. These patterns have been incredibly consistent across all groups of ancient skeletons that we have found to date—until now.

Evidence of metabolic disruption was very rare among the Olmos people. Photo: H. Klaus.  Here, an enamel hypoplasia can be seen on an unerupted adult canine.
Evidence of metabolic disruption was very rare among the Olmos people. Here, an enamel hypoplasia can be seen on an unerupted adult canine. (Photo by Haagen Klaus)

Every archaeological indication of cultural identity and social class independently show that the people buried in Olmos were commoners—beyond the shadow of scientific doubt. Yet, it was to our complete surprise that the skeletons of Olmos appear to represent the healthiest group of people ever documented in the prehistory of the coastal northwestern Lambayeque region.

In terms of bioarchaeological analysis, they are as healthy as the Lords of Sicán in some respects, and even healthier in others. There is no evidence of any infectious disease processes affecting their bones. Levels of degenerative joint disease and anemia are extremely low. Oral health data indicate these people ate a very nutritious diet that was probably not dominated by starchy carbohydrates (i.e., corn). In such a rigid society, how could this be?

Another example of a rather major, but rarely encountered, enamel defect in the Olmos sample. Photo: H. Klaus.
This close-up shows an example of a rather major, but rarely encountered, enamel defect in the Olmos sample. (Photo by Haagen Klaus)

Secrets of Olmos Success

One factor could have involved local ecology. Though a hinterland location, Olmos is characterized by a unique microenvironment that featured greater water availability and precipitation than the rest of Lambayeque.

Another set of clues comes from Spanish census records 500 years later that depict Olmos as growing slightly while much of the rest of the 16th-century north coast underwent free-fall demographic collapse. Such growth is almost unfathomable, but Olmos’s isolation from the epidemics playing out in larger colonial population centers has something to do with it. Also, Colonial Olmos was economically strong, and this probably helped their situation, too.

The new findings lead us to consider deeper relationships between geography, environment, and human biology that may have extended back into pre-Hispanic times. In other words, Olmos may have long been a unique kind of oasis.

An Independent Enclave?

Another explanation—not mutually exclusive with the others—comes back to the relative isolation of Olmos. Near the northern edges of Middle Sicán territory, people lived outside the known bounds of the Middle Sicán heartland.

The Olmos population undoubtedly had to participate in the political economy, producing food, goods, and other kinds of items for the Middle Sicán state, yet the degree to which they did is uncertain.

It is also telling that there was a general lack of Middle Sicán iconography or other goods that carried the symbols of the state in the Olmos burials. There was some embrace of the Sicán Deity and culture, but not much. This aligns with evidence from other sites where Muchik peoples also probably enjoyed relative independence.

We can hypothesize that a booming Middle Sicán economy, lack of oppressive direct rule, and a greater degree of economic and political freedom made for a less biologically and socially stressful life. The total lack of skeletal trauma associated with raiding or warfare also strongly indicates a peaceful quality to this relationship.

One of the only examples of skeletal trauma - a well-healed vertebral crush fracture, which are biomechanical in origin -  caused by a fall, not violence. Photo: H. Klaus.
One of the only examples of skeletal trauma: a well-healed vertebral crush fracture—a type of injury that is biomechanical in origin—caused by a fall, not violence. (Photo by Haagen Klaus)

Giving Voice to the Long-dead

I sometimes think of bioarchaeologists as those who can give voice to the long-dead. We translate and tell the stories of people that would otherwise be lost forever in the passage of time. The skeletal remains of the citizens of Olmos shared with us remarkable and unexpected chapter in the history of the Middle Sicán civilization.

We are now planning our next field season and beyond. We have many more sites to study, new questions, and novel perspectives on ancient Peruvian history that we hope to develop.

Olmos was a very successful project. Jenna, Ana, Butch, and Raul made for a truly great team. However, the El Niño that we feared for 2014 finally hit in early 2015. The most recent forecasts appear to show it currently intensifying, heading towards the strength of the catastrophic 1997-98 El Niño over the coming months. Great concern is growing again.

Lessons in Health and Society From Olmos

The Olmos skeletons, in the end, provide important lessons. First, they help demonstrate the fact that science is self-correcting—always reevaluating itself in the face of new information. As the wholly surprising state of skeletal health in Olmos might seem to call into question our past interpretations about social structure and health, it instead shows that the Middle Sicán world was more diverse and complicated that we once thought. Past work wasn’t wrong. Olmos is a puzzle piece that does not fit, one might say. Such puzzle pieces are perhaps the most scientifically valuable and exciting.

Second, this work also shows us how human health is dynamic. While our health is strongly influenced by genetics or innate biology, even more powerful forces exist that shape the courses of our lives. These are the social, ecological, and economic determinants of health outcomes that have now been studied worldwide and through time by biologists, economists, and bioarchaeologists. Human biology, economy, and social inequality have become entangled with one another in varying degrees over the last several thousand years.

In general, the greater the economic prosperity or degree of social equality, the greater the well-being and the more abundant lives people can live—while the opposite also holds true across time and space. Interestingly, the people of Olmos, while commoners, seemed lucky. They were in a setting where they probably could exploit their relative isolation to its maximum benefit. They show how people can be surprisingly resilient to challenging situations. Still, this was not too common in the Middle Sicán world.

Bioarchaeology: The science of once and future people?  Photo: S. Scholes.
Bioarchaeology: The science of once and future people? (Photo by S. Scholes)

Third, this topic comes full circle. The connection between health, well-being, and social inequality represents one of several key contemporary global problems. Almost one billion people today suffer from either chronic undernutrition or malnutrition (less than 2,000 calories per day) in both developing and developed nations. Hundreds of millions of people suffer from diseases that can be prevented through a combination of education, equitable economic development, and thoughtful public health policies. To me, the 80 individuals who were found in this 1,000 year-old cemetery in Olmos, Peru, are a bridge to today.

They lead us to consider the fact that human society now contains greater degrees of inequality than ever before. This is not an outcome of some imagined natural law, but of the arbitrary social arrangements human beings have conjured up for themselves.

Bioarchaeology may help us to better understand and navigate these contemporary issues in terms of how they arise, how they affect our lives, and the powerful socioeconomic forces and factors that shape human biology and health. The voices of ancient Olmos have reached out to teach us something about our world today—and perhaps provide some guidance for the kind of future that our civilization may choose to create for itself, one way or another.

Read More by Haagen Klaus

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Meet the Author

Haagen Klaus
A native of Long Island, New York, Dr. Haagen Klaus is an assistant professor of anthropology at George Mason University in Fairfax, Virginia. He received his Ph.D. in anthropology from The Ohio State University in 2008, andMA in anthropology from Southern Illinois University in 2003, and a BA in anthropology with a double minors in archaeology and studio art from SUNY Plattsburgh in 2000. Since 2003, Klaus has directed the Lambayeque Valley Biohistory Project in northern Peru. He is an active member of the Society for American Archaeology, the American Association of Physical Anthropologists, and the Paleopathology Association. Klaus is the author of more than two dozen journal articles and book chapters on bioarchaeology and the editor of three forthcoming books.