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Patrick Geary

Collegno, tomb 143. Iron 'multiple' belt elements with silver and brass inlay. Photo by Caterina Giostra

Stony Brook Ecology & Evolution professor and an international team complete DNA analysis that provides insight to how communities formed after the collapse of the Roman Empire

A new study of ancient DNA by a team of international researchers and co-led by Krishna R. Veeramah, PhD, of Stony Brook University, provides insight into the development and social structures of European rural communities following the fall of the Roman Empire. The findings, published in a paper in the Proceedings of the National Academy of Sciences (PNAS), suggest that early medieval elites, or those of higher social status, were initially made up of multiple families with distinct genetic ancestries. However, over time these families intermarried and also the local communities integrated genetically diverse newcomers from a variety of different social and cultural backgrounds.

Collegno, tomb no. 150. End element of belt for weapon suspension in iron with silver and brass inlay. Photo by Caterina Giostra

The research team combined paleogenomic, archaeological, and isotopic data to shed light on the community that used a cemetery in Collegno, Italy, as a burial site during the 6th to 8th centuries CE. Researchers sequenced and analyzed the genomes of 28 individuals from the cemetery and incorporated data from 24 previously published genomes. They also studied individuals’ patterns of social mobility, burial patterns, and diet.

“When the Roman Empire collapsed, we did not really know much about how new communities formed, yet many of these communities would go on to be the basis for modern European countries,” explains Veeramah, an Associate Professor in the Department of Ecology & Evolution in the College of Arts and Sciences, and Director of The Veeramah Lab, which is dedicated the study of evolutionary genomics. “Our study reveals that these elites were genetically surprisingly diverse, and in the process of creating new European communities in the medieval era, families with diverse genetic ancestry would come together to form ruling groups.”

“In 2018, our team published a paper that demonstrated genomic and cultural similarities between Collegno and Szólád, a village in modern Hungary that showed a significant correspondence between individuals with a northern European ancestry in both,” adds Patrick Geary, PhD, of the Institute for Advanced Study.  “Our new study follows the transformation of this Italian community over a century, and shows how new groups moved into and merged with the existing inhabitants.”

The researchers discovered that the Collegno community was initially established by and organized around a network of closely related individuals, likely from several elite families. But over time, they evolved into a single extended lineage spanning at least five generations.

Veeramah and colleagues believe individuals from this lineage had a higher ranking in society based on their richer diets and heavily detailed, and likely more expensively made items they were buried with, such as weapons and elaborate belts [see attached photos].

The findings also show that while the Collegno community was initially established by these elite families, a majority that came from northern Europe, the community later incorporated individuals from other origins and genetic backgrounds into it, including surrounding locals.

Krishna Veeramah. Photo by Dean Bobo

By Daniel Dunaief

People have left all kinds of signs about their lives from hundreds and even thousands of years ago. In addition to artifacts that provide raw material for archeologists, anthropologists and historians, they also left something modern science can explore: their genes.

Genetic information locked inside their bones can add to the dialogue by providing details about what regions people might have come from and when they arrived. A group that includes Krishna Veeramah, an assistant professor of primate genomics at Stony Brook University, is using genetic information, combined with archeological evidence, to gain a better understanding of the events in Europe immediately after the fall of the Roman Empire, between the fifth and sixth centuries.

“We want to test questions that integrate historical and biological information,” said Veeramah, who is working with a multinational team of scientists. “We want to integrate archeological information.”

This is a time period in which there is some disagreement among historians about what happened after the fall of the Roman Empire. Patrick Geary, the principal investigator on a project that traces early medieval population movements through genomic research, said that this period fundamentally changed not only the demographic makeup of the populations but also the social and political constellation of Europe. These scientists are hoping to contribute their analysis of the genetic material of 1,200 people from several cemeteries to a discussion of the history of the continent.

So, how does this work? Paleogenomic data offers information from hundreds of thousands to millions of positions along the genome, which are called markers or single-nucleotide polymorphisms. Looking at the markers in total, researchers can identify small but systematic genetic differences between groups. They hope to determine where an individual’s ancestors are from based on the bones they are studying. They can only come to these conclusions, Veeramah explained, once they have sampled large numbers of people from different geographic areas during that time period. The genetic differences he is seeing are extremely small. He uses enormous pools of data that can allow him to explore subtle patterns, which emerge at the group level.

While the notion of using the genetic code to contribute information to discussions about the movement of groups of people has its proponents and practitioners, Geary and Veeramah recognize the skepticism, alarm and misdirection that comes from exploring subtle genetic differences among various groups of people. “The application of genetics to the human past is dark,” Geary said, pointing to eugenics discussions. “That’s understandable. We are emphatically opposed to such previous misuses of genetic research.” Some scientists, Geary said, are also suggesting that genetic studies will replace manuscripts or other clues. “We need all types of information,” Geary said.

Indeed, in a cemetery in Hungary that contained about 45 graves, Veeramah is studying genetic differences between two graves that are oriented in another direction from the other adult-sized graves. These two graves don’t contain any grave goods and appear to have different construction. The initial genomic analysis of a subset of individuals suggest they have a genetic profile that is different from other members of the cemetery and may show more of a connection to modern people from southern Europe rather than northern and central Europe, like the rest of the samples. The way these two graves were arranged offers intriguing possibilities, Veeramah said. This may suggest that these individuals had a distinct biological identity, which could impact some aspects of their social identity. To reach any conclusions, he hopes to collect more data from more individuals.

Geary suggested the kind of work he and Veeramah are doing, along with partners in other countries, will offer insight into the different paths of men and women. When paleogenomics first arrived as a discipline, historians were slow to embrace it. At the 2008 American Historical Association’s annual meeting, Geary gave a talk at which about 10 people attended. In January, at the 2017 American Historical Association meeting in Denver, Veeramah will discuss how a study of the Lombards offers a framework for integrating history, archeology and genomics. The president of the American Historical Association invited Veeramah and has publicized the talk as a presidential panel.

“I do believe that paleogenomics has become an important aspect of archeological work, and that the newly developed procedures for sequencing and analyzing genetic material adds a whole new dimension to work on archeological sites,” Patrick Manning, the president of the AHA and a professor of world history at the University of Pittsburgh, wrote in an email. Veeramah’s “work on the Lombards addresses an important issue in the Germanic migrations throughout Europe, long debated and now with important new information.”

Veeramah arrived at Stony Brook University in 2014 and lives in Sound Beach. He grew up outside London in Dartford and attended the same secondary school as Mick Jagger. While he likes some of the Rolling Stones songs, he’s more of a Dizzee Rascal fan. Veeramah plans to have a lab installed by next summer, when he hopes to analyze bones from archeological sites shipped from Europe.

In the meantime, he will continue to analyze genetic information coming from partners in Europe. While Veeramah and others in the field have published papers in prestigious journals like the Proceedings of the National Academy of Sciences and Science, they have struggled to receive funding from American funding agencies at the same level as their European counterparts.

“It is somewhat surprising how far behind the U.S. has gotten in this area,” Veeramah said. European grants can be more adaptable and can put more value on multidisciplinary work. “This is a systematic issue for U.S. funding. I hope it will be addressed soon.”