In a new study, we sequenced DNA from a Christian community in medieval Spain, who lived in artificial caves carved into a rock formation.
This is one of many medieval cave communities known to have existed in the Iberian Peninsula, which includes both Portugal and Spain. Why these groups preferred caves to more conventional village dwellings is a subject of long-standing debate among archaeologists. While it may be tempting to speculate about hermits or religious groups, there is little evidence to support such theories.
Our study, published in Science Advances, explores the possibilities, adding genetic analysis to what we know about the physical remains of people from the site’s cemetery. DNA could shed light on the origins of this community, their relationships with each other, and the diseases that plagued them.
The combined information reveals a story of inbreeding, occasional bouts of violence and disease during a fascinating period in history. One possibility is that some of the early settlers were people with military experience, although it is unclear whether they were professional soldiers or not.
The settlement existed from the mid-sixth century to the eleventh century AD. The Early Middle Ages were a dynamic and tumultuous period in many parts of Europe, including the Iberian Peninsula. After the fall of the western Roman Empire in 476 AD, Iberia came under the rule of the Visigoths, who came from northern Europe.
The Visigothic kingdom collapsed after a conquest by Muslim armies crossing from North Africa in 711 AD. This event established a territory known as Al-Andalus, which at its greatest extent covered much of Iberia. However, Christian kingdoms continued to exist in the north of the peninsula and gradually reconquered territory.
What we know of the period in this part of the world is dominated by events in the great cities of Iberia at the time, such as Toledo, Granada and Cordoba. These were hubs of trade, diplomacy and power.
The rural setting of Las Gobas offers a glimpse into life outside the urban centres, in one of the characteristic cave dwelling communities of the time.
Las Gobas is located in the province of Burgos, in the north of Spain, near the village of Laño. It has a cemetery that was in continuous use from the seventh to the eleventh century. It was initially connected to a church, which was also built in the cave complex. By the tenth century, the inhabitants had moved to a more typical rural village, although the cave church and cemetery continued to be used until the eleventh century.
Archaeological excavations at the cemetery have revealed the remains of 41 people. We subjected 39 of them to genetic analysis and 33 yielded enough DNA for gender identification (22 males and 11 females). About 28 remains yielded enough DNA for further investigation with various genetic techniques.
