Dr. Luiz Pezo-Lanfranco, an anthropologist renowned for his contributions to bioarchaeology, and his team of researchers have unveiled a significant study on child mortality at the Quebrada Chupacigarro Cemetery (QCC), situated in the Central Andes. This study, published in the International Journal of Osteoarchaeology, presents new insights into the harsh realities of childhood during the pre-Columbian era, specifically focusing on the Middle to Late Formative Period (500–400 BC). The findings are a pivotal addition to the field of osteoarchaeology, shedding light on the bioarchaeological conditions and living conditions of children during this ancient period.
Discovery and Context: The Quebrada Chupacigarro Cemetery
The Quebrada Chupacigarro Cemetery (QCC), perched on the slopes of Cerro Mulato near the Supe River in modern-day Peru, was first uncovered in 2011. The cemetery serves as a vital archaeological site, providing a rare glimpse into life during a period of significant cultural and political transition. The late Middle Formative to Early Late Formative period saw substantial social upheavals in the Andean region, with populations shifting from centralized, theocratic city-states to smaller, decentralized communities. The QCC site is unique in that it contains 67 well-preserved human burials, 47 of which represent children under the age of eight, offering a precious opportunity to study childhood health and mortality during this transformative era.
The study was designed to explore the bioarchaeology of children during this period, a relatively underexplored aspect of pre-Columbian Andean life. Dr. Pezo-Lanfranco highlighted that the research on child remains from this specific era is scarce, primarily due to the fragility of juvenile skeletons and historical biases in archaeological research, which have often marginalized the study of children’s remains. The QCC site, therefore, offers invaluable information about the lived experiences of children in the ancient Andes, particularly those who perished during the early stages of life.
Anemia and Poor Health in Pre-Columbian Peru
One of the study’s most compelling findings relates to the widespread prevalence of anemia among the children interred at QCC. Through an analysis of the skeletal remains, the researchers identified multiple skeletal markers associated with nutritional deficiencies and disease, such as cribra orbitalia (CO) and porotic hyperostosis (PH). These conditions, which manifest as lesions in the eye sockets and porosity in the skull bones, are commonly linked to anemia, particularly chronic iron deficiency. In prehistoric populations, anemia was a major health concern, exacerbated by poor nutrition, high infant mortality rates, and the stresses of living in densely populated, resource-deprived environments.
Dr. Pezo-Lanfranco and his colleagues observed that the children’s remains exhibited other signs of poor health, such as periosteal reactions (PR), which occur when new bone forms due to infection or inflammation, and linear enamel hypoplasia (LEH), which indicates arrested tooth growth caused by periods of intense physiological stress, including malnutrition and illness. These markers suggest that the children at QCC suffered from a high incidence of infectious diseases, malnutrition, and chronic health stressors. This study revealed that the high mortality rate in the children buried at QCC was not solely due to infectious diseases but was also heavily influenced by dietary deficiencies and the poor sanitation conditions of the time.
Population Density and Its Role in Child Mortality
A critical aspect of the study is its exploration of how environmental and social factors influenced child health during this period. Dr. Pezo-Lanfranco points to the likely connection between high population density, poor sanitation, and widespread malnutrition in these ancient communities. The study suggests that the rise in population density during the Middle to Late Formative transition, along with the decline of centralized, theocratic governments, created stressful living conditions, particularly for children. As populations clustered together in hilltop settlements and fortresses for defensive purposes, limited access to sanitation and clean water created fertile ground for the spread of infectious diseases.
Moreover, malnutrition, particularly among mothers, had a profound impact on infant and child health. Malnourished mothers were less able to provide adequate nutrition to their children, leading to increased susceptibility to infections and diseases. Dr. Pezo-Lanfranco theorizes that the poor health conditions of these children were compounded by a lack of proper sanitation. This theory is supported by previous studies in the region, which have found that ancient Andean communities were plagued by water contamination from upstream settlements, where agricultural practices often used untreated water.
The Supe River, which flows near the QCC, has an irregular flow, likely contributing to seasonal water shortages and floods that would disrupt the regular supply of clean drinking water. The children of QCC may have been particularly vulnerable to the adverse effects of water contamination, which could have contributed to high rates of gastrointestinal infections, including fatal diarrhea.
El Niño and Environmental Stressors
In addition to the social and environmental factors, the study also considers the potential role of climate-related events, specifically El Niño (ENSO) events, in exacerbating health crises. ENSO events, which lead to irregular climatic conditions such as floods and droughts, could have caused significant disruptions to food and water supplies, further exacerbating the already difficult living conditions faced by the residents of QCC. The harsh environmental conditions likely compounded the stressors already faced by children, increasing their vulnerability to diseases and malnutrition.
Pezo-Lanfranco further speculates that these environmental stressors, including periodic water shortages, floods, and changes in the river’s course, may have forced people to concentrate in specific areas, such as the hilltop fortresses of QCC, where resources were more readily available. This clustering would have increased the risk of disease transmission, further intensifying the health challenges faced by the community.
High Infant Mortality and Chronic Stress
Dr. Pezo-Lanfranco and his team discovered that approximately 85% of the bones from individuals below the age of eight showed signs of periosteal reactions, indicating that these children experienced chronic infections or inflammation during their lifetimes. Additionally, nearly half of the individuals who survived into childhood (around the age of 25) exhibited linear enamel hypoplasia, suggesting that these children experienced prolonged periods of nutritional stress or illness.
The researchers’ findings emphasize the extent of early life adversity faced by children in pre-Columbian Andean societies. The high prevalence of anemia, infections, and growth disruptions among these children highlights the brutal realities of childhood during this period. Furthermore, the study indicates that those who survived these early health challenges—often after overcoming severe anemia and infections by the age of three—tended to reach adulthood, suggesting a form of survival resilience amidst a backdrop of systemic stressors.
Future Research Directions and Broader Implications
While the study has provided significant insights into the health and mortality of children during the pre-Columbian Andes, many questions remain unanswered. One of the central questions that Dr. Pezo-Lanfranco and his colleagues are eager to explore is whether the patterns of high mortality and poor health observed at QCC were specific to this region and period or whether they represented a broader trend across the Andes during the Formative Period. Future research may reveal whether similar health outcomes were experienced in other regions, such as in the urban centers of the Caral Civilization (3000–1800 BCE), or among elite populations.
The researchers are also interested in examining whether this pattern of high child mortality and poor health was a characteristic feature of rural and marginalized populations, or whether it was also present among the elites in larger, more centralized Andean societies. This line of inquiry could help determine whether the challenges faced by children in QCC were unique to this isolated community or indicative of a larger societal issue affecting different social strata.
In conclusion, the study of child mortality at the Quebrada Chupacigarro Cemetery offers an invaluable window into the lives of pre-Columbian children in the Andes, revealing the harsh realities of early life during a time of political and environmental upheaval. Through the detailed analysis of skeletal remains, Dr. Pezo-Lanfranco and his team have illuminated the complex interplay between social, environmental, and health factors that contributed to the high mortality rates of children in this ancient society. As research into the pre-Columbian Andes continues, it is hoped that further studies will provide more clarity on the lives of these children and the broader societal conditions that shaped their experiences.
Reference: Luis Pezo‐Lanfranco et al, Preadult Living Conditions During Sociopolitical Transition in Quebrada Chupacigarro Cemetery (500–400 bc), Supe Valley, Peru: Childhood Morbidity and Sociopolitical Change in Prehistoric Central Andes, International Journal of Osteoarchaeology (2025). DOI: 10.1002/oa.3386