Ajeje Brazorf
07-24-2024, 01:44 PM
Multi-proxy bioarchaeological analysis of skeletal remains shows genetic discontinuity in a Medieval Sicilian community
https://royalsocietypublishing.org/doi/suppl/10.1098/rsos.240436
The medieval period in Sicily was turbulent, involving successive regime changes, from Byzantine (Greek Christian), Aghlabid (Sunni Muslim), Fatimid (Shı̄ʿa Muslim), to Normans and Swabians (Latin Christian).
To shed new light on the local implications of regime changes, we conducted a multidisciplinary analysis of 27 individuals buried in adjacent Muslim and Christian cemeteries at the site of Segesta, western Sicily. By combining radiocarbon dating, genome-wide sequencing, stable and radiogenic isotopic data, and archaeological records, we uncover genetic differences between the two communities but find evidence of continuity in other aspects of life.
Historical and archaeological evidence shows a Muslim community was present by the 12th century during Norman governance, with the Christian settlement appearing in the 13th century under Swabian governance. A Bayesian analysis of radiocarbon dates from the burials finds the abandonment of the Muslim cemetery likely occurred after the establishment of the Christian cemetery, indicating that individuals of both faiths were present in the area in the first half of the 13th century.
The biomolecular results suggest the Christians remained genetically distinct from the Muslim community at Segesta while following a substantially similar diet. This study demonstrates that medieval regime changes had major impacts beyond the political core, leading to demographic changes while economic systems persisted and new social relationships emerged.
Most individuals carried mitochondrial DNA haplotypes which are widely distributed across Eurasia; however, SGBN2, a male buried in the Muslim cemetery carried mitochondrial DNA haplotype L3e5 which is primarily found in sub-Saharan Africa. The Y-chromosome haplotypes were suggestive of differences between the cemeteries: individuals from the Muslim cemetery carried haplotypes associated with North Africa (E1b-M81 and E1b-M310.1) and the Eastern Mediterranean (J2b-M241), while four of the nine individuals buried in the Christian cemetery belonged to haplogroup R1b-M269, a haplogroup which is primarily found today in Western Europe.
Against a worldwide panel of 141 modern populations, we observed that all Segesta individuals fell within the PCA-space represented by Europe and North Africa, except for SGBN2, who fell within the diversity of sub-Saharan African populations.
Constricting the analysis to modern Eurasian and North African populations, we observed individuals from the Muslim cemetery showed affinity to one another, plotting between modern populations from Southern Europe, Southeastern Europe, North Africa and the Near East, the latter set including Jewish populations from the Near East and North Africa. One individual, SGBN7, plots between Near Eastern populations and modern North African populations. The individuals buried in the Christian cemetery plot separately in PCA-space, generally situated near modern populations from Eastern, Southern, Southeastern and Western Europe.
Those results indicate a genetic distinction between the groups, with no examples of individuals in one cemetery having a stronger genetic affinity to those from the other cemetery. While the available assemblage was biased toward males, the number of children from the Christian cemetery provided an opportunity to identify offspring of interfaith unions: none were detected.
Continuing at the scale of Eurasia and North Africa, we also evaluated these groups’ affinity to Iron Age Sicani individuals from Sicily, finding the Christian individuals overlapped the PCA-space occupied by the ancient Sicilian Iron Age individuals. When SGBN2 is examined in the context of African populations, we observe the individual plots with groups from West and East Africa.
https://i.ibb.co/0t17gXv/01.png
https://i.ibb.co/4V5tz5y/02.png
https://i.ibb.co/1n5K0WD/03.png
https://i.ibb.co/TrdBzFk/04.png
https://royalsocietypublishing.org/doi/suppl/10.1098/rsos.240436
The medieval period in Sicily was turbulent, involving successive regime changes, from Byzantine (Greek Christian), Aghlabid (Sunni Muslim), Fatimid (Shı̄ʿa Muslim), to Normans and Swabians (Latin Christian).
To shed new light on the local implications of regime changes, we conducted a multidisciplinary analysis of 27 individuals buried in adjacent Muslim and Christian cemeteries at the site of Segesta, western Sicily. By combining radiocarbon dating, genome-wide sequencing, stable and radiogenic isotopic data, and archaeological records, we uncover genetic differences between the two communities but find evidence of continuity in other aspects of life.
Historical and archaeological evidence shows a Muslim community was present by the 12th century during Norman governance, with the Christian settlement appearing in the 13th century under Swabian governance. A Bayesian analysis of radiocarbon dates from the burials finds the abandonment of the Muslim cemetery likely occurred after the establishment of the Christian cemetery, indicating that individuals of both faiths were present in the area in the first half of the 13th century.
The biomolecular results suggest the Christians remained genetically distinct from the Muslim community at Segesta while following a substantially similar diet. This study demonstrates that medieval regime changes had major impacts beyond the political core, leading to demographic changes while economic systems persisted and new social relationships emerged.
Most individuals carried mitochondrial DNA haplotypes which are widely distributed across Eurasia; however, SGBN2, a male buried in the Muslim cemetery carried mitochondrial DNA haplotype L3e5 which is primarily found in sub-Saharan Africa. The Y-chromosome haplotypes were suggestive of differences between the cemeteries: individuals from the Muslim cemetery carried haplotypes associated with North Africa (E1b-M81 and E1b-M310.1) and the Eastern Mediterranean (J2b-M241), while four of the nine individuals buried in the Christian cemetery belonged to haplogroup R1b-M269, a haplogroup which is primarily found today in Western Europe.
Against a worldwide panel of 141 modern populations, we observed that all Segesta individuals fell within the PCA-space represented by Europe and North Africa, except for SGBN2, who fell within the diversity of sub-Saharan African populations.
Constricting the analysis to modern Eurasian and North African populations, we observed individuals from the Muslim cemetery showed affinity to one another, plotting between modern populations from Southern Europe, Southeastern Europe, North Africa and the Near East, the latter set including Jewish populations from the Near East and North Africa. One individual, SGBN7, plots between Near Eastern populations and modern North African populations. The individuals buried in the Christian cemetery plot separately in PCA-space, generally situated near modern populations from Eastern, Southern, Southeastern and Western Europe.
Those results indicate a genetic distinction between the groups, with no examples of individuals in one cemetery having a stronger genetic affinity to those from the other cemetery. While the available assemblage was biased toward males, the number of children from the Christian cemetery provided an opportunity to identify offspring of interfaith unions: none were detected.
Continuing at the scale of Eurasia and North Africa, we also evaluated these groups’ affinity to Iron Age Sicani individuals from Sicily, finding the Christian individuals overlapped the PCA-space occupied by the ancient Sicilian Iron Age individuals. When SGBN2 is examined in the context of African populations, we observe the individual plots with groups from West and East Africa.
https://i.ibb.co/0t17gXv/01.png
https://i.ibb.co/4V5tz5y/02.png
https://i.ibb.co/1n5K0WD/03.png
https://i.ibb.co/TrdBzFk/04.png