Copper Age children in Spain suffered widespread respiratory disease, skeletal study suggests

Children living in southeastern Iberia nearly 5,000 years ago faced frequent respiratory illnesses, according to a new study of skeletal remains from Camino del Molino, one of Europe’s largest Copper Age burial sites.

The site, located in present-day Spain, dates to the 3rd millennium BCE and contains the remains of more than 1,300 people. Communities used the burial cave for over 700 years, creating a large collection of human remains from different generations. Among them, archaeologists recovered 48 intact skeletons belonging to children and adolescents. Such finds are rare because bones in communal graves often become mixed or damaged over time.

Researchers examined the young individuals for signs of disease preserved in their bones. Their findings, published in the International Journal of Paleopathology, suggest respiratory infections affected a large part of the population and played a major role in childhood illness and death.

The numbers paint a striking picture. Forty-four of the 48 individuals, or 91.7 percent, showed at least one skeletal alteration linked to poor health. Porous skeletal lesions appeared in 43 individuals, representing 89.6 percent of the sample. Signs associated with respiratory infections appeared in 33 individuals, or 68.8 percent.

Many children carried evidence of both conditions. Researchers identified the co-occurrence of porous lesions and infection-related bone changes in 32 individuals, equal to two-thirds of the sample. Statistical analysis showed children with porous skeletal lesions were more than 11 times more likely to display signs linked to respiratory disease.

The team recorded several types of bone changes. Some appeared as porous areas in the skull and thigh bones. Others included small grooves and pitting on the inner surface of the skull, along with abnormal bone growth in the spine, pelvis, sacrum, and hip region. Previous studies have linked some of these lesions to infections spreading through the bloodstream, including the early stages of tuberculosis.

Lead author Sonia Díaz-Navarro and her colleagues argue that the pattern points toward repeated or long-lasting respiratory illness rather than a single disease episode. The lesions appeared too frequently and across too many age groups to be explained only by normal childhood growth.

Age played an important role. The highest rates of skeletal changes appeared among children between one and four years old and among adolescents aged ten to fourteen. Researchers identified these same age groups as periods when young people faced greater vulnerability to respiratory infections.

The study found no meaningful differences between males and females. Among the individuals whose biological sex could be estimated, both groups showed similar rates of disease-related changes. Such a pattern suggests shared environmental conditions affected children throughout the community.

Daily life likely contributed to the spread of illness. Children would have spent time in homes filled with smoke from indoor fires. They also lived around dust, food-processing activities, animal waste, and livestock. Constant exposure to these conditions could have increased the risk of respiratory disease and contact with infectious organisms.

The burial evidence reveals another aspect of life at Camino del Molino. Researchers found no indication that children suffering from illness received different funerary treatment. Individuals with visible health conditions were buried alongside others in the same communal setting. Previous work at the site identified people with healed skull surgeries and other physical differences, yet burial practices remained consistent across the population.

The authors describe Camino del Molino as a rare opportunity to study childhood health on a population scale rather than through isolated cases. The unusually large number of preserved non-adult skeletons allows researchers to examine broader patterns of disease, survival, and mortality within a prehistoric community.

Future studies will focus on ancient DNA and other biomolecular evidence. Researchers hope such analyses will identify tuberculosis bacteria or other respiratory pathogens within the remains. Additional work examining diet and family relationships could help explain why some individuals faced greater health risks than others.

The evidence from Camino del Molino suggests respiratory infections were a common part of life for many children during the Copper Age. Those illnesses left traces in their bones, preserving a record of childhood health that survived for nearly five millennia.