A UAB team, in collaboration with the archaeology firm ATICS, has identified bubonic plague bacteria, Yersenia pestis, in an individual from the 14th century buried in the cemetery of the Besora Castle, in the county of Osona. The discovery confirms that the Black Death, which devastated Europe in the Middle Ages, also reached rural regions of inland Catalonia.
The genomic study was carried out by researchers from the Biological Anthropology Unit in the laboratory of ancient and modern DNA of the UAB, under the direction of Cristina Santos, researcher of the Department of Animal Biology, Plant Biology and Ecology.
The analysis was carried out on the human remains of a burial that last year attracted the attention of archaeologists and anthropologists studying the remains of the parish cemetery of the church of Santa Maria, located in the Besora Castle. The burial contained the skeletal remains of three adults who were buried simultaneously. The scene, due to its location and disposition within the grave, with no signs of violence or other observable pathology, suggested an epidemic episode. Carbon 14 dating placed the burial between 1300 and 1370, coinciding with the great Black Death pandemic of the 14th century. This prompted genomic analyses to try to validate the hypothesis that these could be deaths from that major pandemic. Despite the degradation of the samples, UAB researchers identified ancient DNA of the Black Death bacteria in the dental remains of one of the individuals.
In addition, in this year's archaeological excavation campaign, two more graves with multiple burials were located, in this case with the remains of three individuals, both adults and children, in each one. The fact that these burials are close to the one located last year and that they are at levels that would correspond chronologically to the great Black Death pandemic of 1348 leads the research team to believe that they could also be individuals who died from the infection. A first genomic analysis will be carried out in the coming months to confirm this.
"These are exceptional discoveries, which provide evidence of the high rate of mortality caused by the plague in rural areas of inland Catalonia", Cristina Santos points out.
The identification of the Black Death bacterium opens the possibility of undertaking pioneering studies related to adaptive mechanisms in the response to pathogens in human populations in Catalonia. "The fact that the cemetery of the monumental complex of the Besora Castle has remains of burials from the eleventh to the nineteenth century may allow in the future to conduct empirical testing of the genetic changes that have occurred and discover which genetic variants could have increased in frequency as a result of the pandemic," concludes Cristina Santos.
The same UAB research team already identified the Black Death bacteria last year in Vilafranca del Penedès, in the necropolis of Cal Pa i Figues. The laboratory of ancient and modern DNA of the Biological Anthropology Unit of the UAB was then the first in Catalonia to detect the bacillus. The results obtained now consolidate it as one of the most important infrastructures in the country for the analysis of ancient DNA.
Headquarters of the UAB Archaeology Campus
The excavation of the parish cemetery of the church of Santa Maria in the Besora Castle is being carried out within the framework of the four-year archaeological and palaeontological research project (2022-2025), "Els orígens del Bisaura: l'església i el seu entorn. Conjunt monumental del castell de Besora (Santa Maria de Besora)", promoted by the Fundació Privada Conjunt Monumental del Castell de Besora and approved by the General Direction of Cultural Heritage of the Government of Catalonia.
The research work is directed by UAB elcturers Xavier Jordana and Nuria Armentano, from the Biological Anthropology Unit of the Department of Animal Biology, Plant Biology and Ecology; and Cesc Busquets, from the Archaeology Area of the Department of antiquity and Middle Age Studies, together with Marta Fàbregas from the company ATICS S.L.
The monumental complex of the Besora Castle is one of the sites of the UAB Archaeology Campus which every year hosts students of the master's degree in Biological Anthropology (UAB/UB) and the bachelor's degree of Archaeology of the UAB, who for two weeks are fully immersed in the fields of archaeology and anthropology.
The research is supported by a four-year project grant from the Department of Culture of the Government of Catalonia and the support of the company ATICS S.L., as well as the Association of Friends of the Bisaura and the Santa Maria de Besora Town Council.
