The trace of suffering, in the bones
STRI/DICYT A short distance from what is now known as the Villa de los Santos, on the Azuero peninsula, there were many cases of an infectious disease caused by bacteria of the genus Treponema, possibly syphilis or yaws. Transmitted from person to person through contact, its consequences were recorded in the bones of those who were sick.
Two millennia later, this would be detected by Nicole Smith-Guzmán, bioarchaeologist and paleopathologist at the Smithsonian Tropical Research Institute (STRI). Thanks to her training, she knows even the smallest detail of all the bones in the human body. And if she notices anything out of the ordinary, she starts researching why.
Her discovery of the Treponema among the bones in indigenous cemeteries of the Cerro Juan Díaz archaeological site in Azuero, is just one of several pathologies that she has found among those who preceded us. And although we are used to hearing that the Spanish plagued indigenous groups with diseases once they arrived in the isthmus, what did these ancient settlers suffer from before the arrival of the Europeans, and what does this tell us about their lifestyles?
In the remains found at the site in Azuero, other curious signs emerged. The bones of the inner ear of various male skulls had unusual bone growth. Smith-Guzmán found that this occurs frequently among surfers and that it is associated with marine activities when there are cold wind currents. Aware that these human groups highly valued two species of Spondylus shells for making jewelry, they inferred that the men with the bony growth used to dive in search of this mollusk in the Pacific, where there are very cold currents in the summer.
It is not the first time that we learn more about the ancient human groups of Panama through their bones. However, it was not until the 1990s that this became of interest. Before that, the field of archeology focused mainly on material culture. In some cases, encountering skeletons in an excavation was even considered inconvenient. Bioarchaeology and paleopathology were not recognized fields.
“The archaeologists themselves did not understand the great importance of this discipline. When I was a student, human remains were considered a major nuisance. They were in the way of the cultural stratigraphy, which was considered the most important thing,” admits Smithsonian archaeologist Richard Cooke, Nicole's adviser.
Before Nicole, Colombian student Claudia Díaz had made an effort to study the remains of Cerro Juan Díaz with a bioarchaeological focus for her bachelor thesis. It was 1999 and the techniques were not as advanced as now, but somehow Claudia prepared the ground. In her thesis she had already made inferences about the diets of these ancient populations, something with which Nicole continued when she arrived at STRI a few years ago.
From the teeth, for example, she was able to draw some conclusions: that the diet was rich in foods with high sugar content, mainly corn, but also cassava, sweet potatoes and fruits. In addition, she was able to deduce that they consumed a soft food diet after finding jaws that had not fully developed. Misaligned teeth, in other words. Today this can be fixed with orthodontics, but in those days there was nothing that could be done.
Certain community residents also experienced rare diseases, such as brittle bone disease, which could be due to low genetic diversity. According to chronicles from the time of the Spanish contact, each community that the Spanish encountered on the plains west of Chame spoke a different language - "language of Chirú", "language of Natá" and so on.
“This could indicate that the same indigenous family lived for a very long time in the same territory, no matter how small it was. Neighboring relatives became their enemies even though they always traded with each other in times of peace,” explains Cooke.
These rare pathologies still occur in modern society. As well as cancer and venereal diseases, which our ancestors did not get rid of either. The signs of Treponema that Smith-Guzmán found in Azuero's bones seem to be more linked to syphilis than to yaws. This was deduced after finding a specific syphilis malformation on a tooth. And among the remains of another site in Bocas del Toro, she found bone cancer, the first report of one among pre-Hispanic sites in Central America.
It was a teenager from the fourteenth century. And her burial was atypical: she was in Cerro Brujo, a settlement already abandoned before her death. That she had been buried there points to her ancestral ties to the site.
After all, what is the use of understanding ancient diseases? For starters, it allows us to better understand them in their current context. In the case of common conditions such as cancer, the assumption is that they did not impact humans in the past.
"By pointing to examples in populations from several centuries ago, we can verify these notions and help the medical field to reduce possible risk factors that lead to the spread of the disease," explains Smith-Guzmán.
It also provides an opportunity to learn more about the effect of diseases on bones. Many afflictions can have a silent effect on them. Malaria seems to be one. In this case, paleopathologists such as Nicole set out to search for typical malaria bone lesions in ancient human remains, while clinicians did similar work in infected mice.
"In this way, paleopathology and clinical medicine can build on each other's findings to advance understanding of the pathophysiology of disease," adds the STRI scientist.
For her, a last aspect that is rarely taken into consideration is how paleopathology contributes to understanding the role of diseases in human history.
Diseases have often influenced historical events, but they are neglected in the documentation of these events.
"Paleopathologists can find evidence of this disease in human remains to better understand that event," says Smith-Guzmán. "In addition, we are increasingly interested in learning about how members of a community cared for their patients."
In some ways, highlighting the empathy that there was in the past towards the sick can give us hope during difficult times such as the pandemic that we are experiencing today.