The Mystery of the 48 Children: What a Mass Grave from the Copper Age Reveals About a 5,000-Year-Old Health Crisis

The Buried Mystery of Camino del Molino

Nearly 5,000 years ago, during the third millennium BCE, a vast circular burial cave carved into the rock served as a resting place for the deceased of a community in Spain. Known as Camino del Molino (CMOL), this site is the largest mass grave from the Copper Age in Europe. More than 1,300 individuals have been discovered there. The site was used repeatedly for over 700 years. Over time, a veritable tangle of human bones belonging to men, women, and children formed there.

Prehistoric communal graves rarely preserve intact skeletons. The remains of non-adult individuals are even more exceptional to find in this condition, as the bones are often rearranged over the centuries, poorly preserved by the elements, or simply missing from the archaeological record. However, at the CMOL site, the research team succeeded in recovering 48 intact skeletons of children and adolescents.

A new study published in the International Journal of Paleopathology examined this archaeological treasure trove following years of meticulous excavations and analyses. This work offers a rare opportunity to examine skeletal changes associated with respiratory diseases. Scientists can thus accurately assess the impact of these conditions—which may include tuberculosis—on the health and survival of children during that distant period.

A Silent Pandemic Etched in Bone

The exceptional preservation of such a large number of complete children’s skeletons allowed the research team to identify patterns across entire bodies, rather than being limited to fragments or isolated bones. The results of this analysis are staggering. Of the 48 individuals examined by the team, 92% exhibited at least one bone abnormality directly associated with a disease.

Among this heavily affected group, approximately 67% showed both signs of porous bone—primarily localized in the skull and leg bones—and changes linked to infections associated with respiratory diseases. Dr. Sonia Díaz-Navarro, the lead author affiliated with the University of Burgos, elaborates on the nature of these observations. “The pattern we observe likely reflects a broader burden of recurrent or prolonged respiratory disease rather than a single pathogen,” she explains.

A common medical hypothesis suggested that similar bone lesions could occur naturally during growth spurts in early childhood. However, the researchers reject this single explanation for the CMOL site. These lesions appear far too frequently and are consistently accompanied by other signs of respiratory infection across all age groups examined, including adolescents. Processes related purely to physiological growth are therefore insufficient to account for the extent of the markings observed on the remains.

The Ages of Vulnerability and the Environmental Trap

A more detailed examination of the bones revealed very distinct periods of vulnerability within the group. The youngest children, aged 1 to 4, as well as young adolescents aged 10 to 14, had the highest rates of bone changes. Researchers identified serpentine grooves and pitting on the insides of skulls and vertebrae, as well as on the hip and pelvic bones.

Previous scientific studies have linked these specific marks to an early stage of tuberculosis, a period during which the bacteria are still actively circulating in the bloodstream. The study highlights that these peaks in infection correspond precisely to the age ranges when children and adolescents are most vulnerable to lung infections in general. Notably, the majority of the children exhibited similar bone changes, suggesting that shared living conditions may have contributed to the disease, ruling out gender-specific activities as a factor in exposure.

The daily environment of this prehistoric community played a central role in the spread of respiratory illnesses. Dr. Díaz-Navarro details these harsh living conditions. “Children living in the settlement would also have been exposed to many of these same environmental factors: indoor smoke, dust, organic particles from crafts and food processing, close contact with animals, and potentially zoonotic pathogens,” the researcher states.

Absolute Equality in the Face of Death

In the face of illness and death, the community of Camino del Molino appears to have adopted an approach marked by profound equality. According to Dr. Díaz-Navarro’s observations, individuals showing obvious signs of severe illness were not buried any differently from their peers. Funeral rites did not vary at all based on the deceased’s state of health at the time of death or the suffering they endured.

“The available evidence suggests that individuals received the same general mortuary treatment regardless of their pathological condition,” states Dr. Díaz-Navarro. The inclusion of all community members, with no apparent exceptions, in this vast circular communal grave highlights a social structure that was uniquely inclusive toward disability or extreme physical pain.

This uniformity in funeral treatment becomes particularly meaningful when one observes the anomalies present in the skeletons. “This is especially significant because Camino del Molino includes individuals with highly visible or significant conditions,” the researcher explains. Among the remains exhumed from the burial cave were individuals who had undergone a complex surgical procedure on the skull, known as trepanation. Archaeologists even identified the remains of a person with dwarfism, buried alongside the other members of the group without any spatial or ritual distinction.

Next Steps in Understanding Our Ancestors

Research at the Spanish Copper Age site is far from over, paving the way for new discoveries. Future studies based on ancient DNA sequencing could indisputably confirm the presence of tuberculosis bacteria or other diseases specific to CMOL. At the same time, analyses combining ancient DNA and isotopic studies are already planned to better understand the habits, diet, and kinship ties among these individuals.

These upcoming investigations will not only provide a more precise list of diseases in circulation but also shed light on how age, gender, social roles, and diet may have directly influenced living conditions. The extent of this health crisis among the youngest members of the population raises questions about the rest of the population. “We still need to understand whether similar patterns existed among adults, and whether certain groups were more exposed or more vulnerable,” says Dr. Díaz-Navarro, setting the course for future excavations.

The current study paints a grim picture of childhood illness and mortality on the Iberian Peninsula during the Copper Age. Despite this finding of great vulnerability, Dr. Díaz-Navarro concludes by highlighting a deeply human social dimension of these ancient peoples. “Illness, disability, or unusual physical conditions did not necessarily lead to exclusion or distinct burial practices,” she says. Readers wishing to explore this monumental work in depth can consult the article titled “Porous skeletal lesions and respiratory infection-related changes in Chalcolithic non-adults: A biocultural approach from Camino del Molino (southeastern Iberia),” co-authored by Sonia Díaz-Navarro and her team. It was published in the journal International Journal of Paleopathology (2026), with further details available via the DOI: 10.1016/j.ijpp.2026.04.001.

According to the source: phys.org

The Mystery of the 48 Children: What a Mass Grave from the Copper Age Reveals About a 5,000-Year-Old Health Crisis