37. TallBear, Native American DNA, 5.
38. For the idea that archaeogenetics undermines racism, see Reich, Who We Are, 96–97; Carl Zimmer, She Has Her Mother’s Laugh: The Powers, Perversions, and Potential of Heredity (New York: Dutton, 2018); Howard Wolinsky, “Ancient DNA and Contemporary Politics,” EMBO Reports 20, no. 12 (2019): 1–6; Jonathan Shaw, “Telling Humanity’s Story through DNA,” Harvard Magazine 124, no. 6 (2022), https://www.harvardmagazine.com/2022/07/feature-ancient-dna.
39. See Strand, “0.01%.”
1 Gained in Translation: Interdisciplinary Challenges in Ancient DNA
Charlotte Mulcare and Mélanie Pruvost
The oldest cliché in the world is about “what’s lost in translation,” but you don’t very often read much intelligent about what’s gained by translation, and the answer is everything. Our language is a compendium of translation.
—Sam Hamill, 20031
An archaeologist, a media historian, a historian of ideas, and a geneticist walk into a bar. They begin an enjoyable discussion about the challenges of interdisciplinarity and conflict in current practice in ancient DNA (aDNA) research. The warm feeling of being in total agreement, amplifying arguments and completing each other’s sentences, comes to an abrupt halt when the geneticist suddenly asks how the group’s criticisms of archaeogenetics could be addressed by changes in working culture. As punchlines go, this one is not well received. In the deafening silence that follows, the geneticist argues that criticism without any attempt at resolution or roadmap to redress shortcomings is a little nihilistic. The archaeologist is, in turn, concerned that calls to improve practice along prescriptive guidelines can be a way to control criticism and, to some extent, avoid it by formulating a set of given solutions to all problems. The historian of ideas argues that the genre of best practices serves as a way of glossing over the more profound and structural issues in aDNA research. The media historian, finally, suggests that the purpose and value of humanities scholarship should not be reduced to its practical applicability. A critical analysis of practices in aDNA research would be compromised if it encompassed an interest in the furtherance of that particular field of research.
Over the following years, the Code Narrative History research team took part in many similar discussions in a variety of settings (cafés, libraries, Zoom), ranging in tone (muddled, bracing, catastrophic) but broadly following a similar trend: an optimism regarding the potential of the discipline and a desire to resolve issues set against the need to critique and unpick them. Equivalent discussions in the Ancestra team (also interdisciplinary) revealed some deep schisms in understandings of language, methodology, and practice.
The idea that conflict in the field of human aDNA research rests along disciplinary boundaries is not particularly controversial. Recent years have seen extensive conflict within the field of archaeogenetics,2 and a common reaction in the literature posits best-practice publications and guidelines as a potential solution. These generally seek to address existing grievances and to provide a consensus for a new, more enlightened culture of effective collaboration across disciplines.3
At first glance, these are positive developments and often lauded as such. Yet our combined experiences of working in interdisciplinary environments have given us pause for thought. While admirable in intention and principle, best-practice publications do not address the deeper challenge of implementing their recommendations in a working environment where deep cultural schisms impede many of the advocated measures.4 This avenue may also risk contributing to a culture in which researchers cannot articulate problems unless they believe there is a way to solve them. Furthermore, while improved communication is often welcomed as the silver bullet for successful collaborations, critical voices—particularly those of Indigenous communities and marginalized groups—are often absent from the generation of these guidelines, guidelines that are themselves a product of the environment they seek to regulate.5
However, it is also understandable that our colleagues (and reviewers) are reluctant to engage with lengthy articles that offer relentlessly negative criticism. As an alternative to both strategies, we suggest there is a value to articulating the fault-lines inherent in archaeogenetic discourse, without seeking to impose specific direction on research teams. In our own interdisciplinary teams, which included scientists and humanities scholars, we found that conflict could be a precursor to innovation, and it is this benefit that we seek to explore here. Through unpicking dialogues that have been marred by misunderstanding, and by identifying places where the axioms of different research areas collide, we believe individual projects can benefit by increasing awareness within a team. In this way, awareness itself becomes a driver for improved practice, increased respect and sensitivity to nuance. This type of reflection need not result in a tangible end product, such as an ethical roadmap or processual toolkit. In any case, the research questions, environments, and eccentricities of any given team are often so specific as to render a universal approach of limited use. Our proposed approach would instead be to use insights derived from conflict within a group as a means to enhance a specific research project.
In this chapter, we use our own experiences as geneticists to reflect on the sources and dynamics of misunderstandings that emerged during the course of our research. Despite differences in our projects’ ambitions and aspirations, we were able to identify a series of key themes, or clusters, of common problems. In this reflection, we sit with conflict in order to understand fully what is being lost—and gained—in translation. Our hope is that this exercise, though challenging, may bring unforeseen benefits to other research projects open to this kind of experiment.
A Tale of Two Projects
Code Narrative History: Making Sense of Ancient DNA in Contemporary Society (2018–2021) was an interdisciplinary research project based at Stockholm University in Sweden. The project investigated how ancient genetic sequences are used to formulate meaningful historical narratives, which often include claims of identity and pertain to cultural and sociopolitical issues in contemporary society. A key component of the project was understanding how actors from diverse fields—researchers in science and the humanities, as well as museum curators, journalists, and academic editors—understand, interpret, and explain new scientific data through existing cultural frameworks and traditional historiographies.
Members of the project recognized that a prerequisite of archaeogenetics is the generation of genetic data, which often places a strong reliance on a laboratory team formed by a community of scientists. Collaborations may, therefore, involve a predominance of scientists relative to humanities researchers and archaeological scientists, with the influence of a lab-based culture at their core. This paradigm was subverted in Code Narrative History, as the team included an archaeologist as the principal investigator, a media historian, a historian of ideas, and only one member (Charlotte Mulcare) with a background in genetic science.
The focus and composition of the Ancestra project, of which Mélanie Pruvost is principal investigator, differed significantly from Code Narrative History. Despite France’s substantial archaeological and historical wealth, few archaeogenetic data were available for France when the Ancestra project was initiated toward the end of 2015 with the support of Agence Nationale de la Recherche funding. The objective was to study the origins and dynamics of the settlement of France since the Neolithic period or, more precisely, of the territory corresponding to present-day France. The approach involved combining culture and genetics to focus on what archaeologists call “transition periods,” and, in doing so, to inform an ongoing debate: To what extent are visible changes in material culture, evidenced through archaeological remains, reflective of changes at a population level—that is, the movement of groups of people—and to what extent are they the result of acculturation? The project covered the Mesolithic to the Early Middle Ages, a broad chronology during which profound technological, cultural, and social changes occurred, including the introduction of agriculture, the emergence of people following a sedentary lifestyle, and the mastery of metallurgy.
The Ancestra project reflects many of the core features in archaeogenetics, including a focus on identity, migration, and stories of national origin. In terms of methodology, the work was mobilized by technological advances linked to high-throughput sequencing, which made the mapping of ancient genomes technically feasible and affordable. The project also benefited from the discovery of an anatomical region that acts as a veritable “vault” for ancient DNA: the dense petrous part of the temporal bone.6 Both these drivers—characteristic of archaeogenetics research after 2015—were complemented and ignited by the interest of the French archaeological community, enabling the establishment of a strong corpus for analyses and a dynamic interdisciplinary culture.
From our established standpoints as researchers with a genetic background in these two projects, we consider some of the issues that have caused friction and conflict in the field. While we are conscious that the field of archaeogenetics spans a wide remit, here we consider the five particular areas pertinent to aDNA from human remains.
Questions
The gap between the types of questions that researchers of the past may seek to answer and the types of questions that can be realistically addressed in analyses of aDNA burdens many collaborations, with a mismatch of expectations. This disconnect may undermine the first task of an interdisciplinary group—the generation of coherent, appropriate research questions.7 Notably, the desire to push the data too far and to address “the big questions” was, in our experience, not necessarily limited to the archaeologists or humanities researchers on a team, who were less familiar with the scope of genetics research. The problem appears rather to be a product of interdisciplinarity.
Archaeologists in the Ancestra project were often interested in how the genetic identity of different cultural groups related to their respective origins. This line of inquiry rests, in turn, on whether or not the differences observed in the funerary treatment of certain individuals correspond with observable genetic differences. At the genetic level, variation between individual humans and human populations is relatively low: we need a certain amount of genetic data to see a meaningful resolution. In an ideal world, to make the kinds of inferences commonly discussed in archaeogenetics, we would need a good knowledge of the genetic diversity of ancient human populations. Unfortunately, this knowledge is lacking, due to scarcity of samples and the degradation of genetic material over time. This brings substantial uncertainty into the work. In the Ancestra project, there was a sense from the archaeologists that genetic data could be used to address a broader scope of questions, and with more confidence than was actually the case. In the Code Narrative History team, an interview-based research exercise found this same trend but among the scientists, suggesting that underinterrogation of material is not confined to either archaeologists or geneticists but is a phenomenon within the discipline.8
Inflating research questions beyond the scope of genetic data seems to be a particular (and oft-cited) concern in the world of archaeogenetics. Here, perhaps more so than in other branches of genetics, scientific and academic caution coexist with the drive to feed a diverse audience hungry for the fusion of romanticized ideas from the distant past with the clarifying authority of genetics. This may in part be driven by a certain fascination with key themes such as gender roles and origin stories9 but may also be a product of interdisciplinarity itself, which amplifies the impact of its constituent knowledge components.10
The literature appears to be rich with titles seeking to answer the “big” questions that translate well to a broader public interest. A quick scan of recent literature supports this perception: out of sixty-four Medline indexed archaeogenetics papers scanned for relevance, focusing on humans and published over the last year, forty-one were data-driven publications in that they applied aDNA material to archaeological research (as opposed to guidelines, reflections, or methodology papers).11 A scan of titles and abstracts found that, of these, ten sought to answer historical questions pertinent to entire continents, nine covered time frames of over 10,000 years, and seven claimed to solve the question of origins for various ethnic groups.
This scan—albeit fairly rudimentary—indicates an ambitious scale of intention. It is not our intention to critique the science or rationale for these research questions, and it is important to note that it is the minority of research groups that run the gamut of solving such epic riddles. Instead, we want to draw attention to the trend for “soundbite titles” that suggests that archaeogenetics has assumed a center-stage position in an increasingly mediatized landscape. This is a truism that the Code Narrative History team witnessed during discussions with journalists and media specialists, who noted that the more bounded aspects of scientific inquiry were often pared back in favor of “big stories.” In this respect, groundbreaking conclusions and enticing prospects satisfy the requirements of popular science consumption and provide headline-generating research results.12 The idea that mediatized research may be stimulating a cultural shift in the structure and formulation of research questions is far from new, and may reflect a more general trend in academia. An emerging body of literature has postulated that academic outputs now seek to keep pace with a fast-moving attention economy which, increasingly, is linked to academic funding and tenure.13
As a relatively new discipline, archaeogenetics enters an arena already rich with context, content, and questions grounded in two very different research traditions. Research questions in the archaeogenetic field frequently reflect the broad historic lines of inquiry embedded within some strands of popular-scientific history or archaeology, but with genetic analyses they become distanced from the methodological frameworks that first conceived them. In the archaeological sciences and the humanities, multiple factors of inquiry intersect and this level of interaction remains in play throughout a research project. Genetic studies, in contrast, seek to identify controlled and distinct variables that can be used to address a focused avenue of interest. Critical inquiry in the humanities often seeks to “problematize”—that is, to increase complexity, search for discrepancy, elucidate and unpack meaningful messages that may cause conflict and confusion if they remain hidden. This is not to say that geneticists involved in collaborative projects with historians or archaeologists are unaware of the broader complexity. It is rather that they tend to avoid the open-ended analyses that are more commonplace in archaeological research. Instead, genetic research is orientated toward answering questions, even where the findings are speculative, negative, or puzzling. As a fusion of starkly different yet equally valid traditions, archaeogenetic research questions thus oscillate between these two ideals, and the attempt to develop a working hybrid can cause researchers to feel there have been “conceptual disagreements” that have yet to be resolved.14
Words
At the heart of many of the misunderstandings we witnessed in archaeogenetics was a disconnect in the way that our teams used language. This disconnect is perhaps an inevitable consequence of our natural assumption that a familiar, frequently used word has a shared meaning. If we take it for granted that the way individuals within interdisciplinary (and often multilingual) teams use language will vary, exploring a shared vocabulary might be a valuable first priority. This search for a common language has been explored in other areas of interdisciplinary studies, such as environmental science, engineering, economics, and ecology.15
Several words saw our own teams at cross purposes. As geneticists, we used the terms “population,” “significance,” and “hypothesis” with very precise statistical definitions, yet as these words are also used in common parlance, our colleagues from the humanities interpreted them differently. The understanding that conclusions reached through mathematical processes do not constitute “proof” in the literal sense is an accepted, yet not always articulated, part of scientific parlance. As the results of archaeogenetic research venture beyond a scientific readership, the risk that a statistical conclusion is given a heavier weighting than merited appears to be a hazard of archaeogenetics. This is a risk that can be negated or exacerbated, depending on the language used by researchers at write-up and in subsequent communication with popular media. Conversely, we also recognize that we as geneticists were sometimes wrong-footed by terms such as “gender,” “kinship,” and “ethnicity,” which our humanities and archaeologist colleagues viewed as socially constructed, situated, and intersectional.
Speaking at cross-purposes can potentially derail a project: for example, the term “ancestry” in genetics assumes a basis of biological inheritance, yet as Stewart B. Koyiyumptewa and Chip Colwell show in their chapter in this volume, a community cocreating an archaeogenetics research project used a definition of ancestry based on much broader, and extragenetical, social kinship dynamics. In such a situation, a reductive insistence on a biological definition would have caused significant problems and led to incorrect conclusions.
For the Ancestra team, an initial challenge concerned the use of the word “France,” as the work was country-specific. When referring to genetic populations or human remains, archaeogeneticists often attribute a country or location and time frame (such as the Neolithic or Mesolithic) as a convenient shorthand, yet clearly these descriptors would have been meaningless to the individuals to whose remains the terms are ascribed. We locate ancient people in the area that they were buried in (not necessarily the area of their birth, life, or personal identification) and anchor them using the language of our own time as the nomenclature of their own is unknown. For the archaeologists in a team, ascribing the terms of nation-state or time period to genetic data risks introducing notions of the cultural achievements associated with that nation or time into the analysis. And as geneticists, we may bring unconscious bias into our interpretation of genetic relatedness. Researchers can and do, to some extent, anonymize samples—this process can successfully divorce cultural associations and labels from samples, rendering aDNA into a more neutral framework. Yet, however we approach the naming of our genetic data sets, their reintegration into the full gamut of evidence from historical, archaeological, and even contemporary sources is an exercise that may require significant caution.16
For the nongeneticist researchers in the Code Narrative History team, the term “whole genome analysis” was initially thought to refer to the complete extraction and sequencing of the totality of an ancient genome. While it may be (more or less) possible to sequence the majority of a modern genome, ancient genomes are usually decayed or fragmented. In reality, while geneticists may seek to sequence an entire ancient genome, only a proportion—sometimes a very small proportion—of genetic material will be recovered. This misperception, common to most lay readers (and many journalists), tends to elevate expectations of the data. This misunderstanding can be exploited when research findings enter the public domain: here, media representations give a strong impression that when teams “sequence a whole genome,” every letter of the genetic code from a historical individual has been captured with perfect confidence. It is not difficult to see how this happens: intuitively, the language is suggestive, and the hype surrounding findings lends itself to this interpretation. While we may consider the sequencing of any ancient genetic fragment to be an achievement worthy of excitement, it is not always evident in the outputs quite how small a proportion of this “whole” genome has, in reality, been decoded. Researchers bear some responsibility here for ensuring that communications signpost—for a lay audience—the coverage of ancient genomes and the relative proportion of material retrieved.
The divergence in the language used to describe ancient human remains is an area where the differences between archaeological and genetic sciences come starkly to the fore. For archaeologists, often with direct experience of excavation and presence at a burial site, the individual human to whom the DNA belongs is a tangible and real presence throughout the research. In work with the Code Narrative History team, Mulcare’s colleagues talked about “human remains” and “individuals,” and—when referring to a group of burials—the emphasis was on the “people” who were buried there. Conversely, she came to the project handling data labeled as from a “sample” rather than a person and thought of groups in terms of defined “populations.” These discrepancies in the use of language are replicated across publications and informal dialogue. Ensuring the continuity between a person and their genetic code has broader repercussion in terms of ethics, respect, and provenance. It is, perhaps, a useful challenge for teams to strive for a balance between acknowledging the humanity inherent in a person’s remains, while understanding that the universal language of genetics places the individual into a broader human story.
While these differences in terminology may be easy to clarify through discussion, the assumptions underpinning them frame our understanding of research in ways that are harder to navigate.17 These profound differences are often downplayed in calls for best-practice consensus.18 Such definitional impasses in the field—along with some of the difficulties they create in theoretical analyses—can be overcome by recognizing the fluidity of language and allowing different terminologies to coexist with equal weighting. For example, a “population” can simultaneously mean a statistically defined group or a culturally defined one, as long as differences are understood by all parties involved and made clear in popular outreach. This ambiguity can be respected for the lifespan of a research project. The risk of ignoring a discrepancy goes beyond mere confusion and/or unease. In an increasingly stark political world, the complexity behind words can even be dangerous, as Magnus Fiskesjö shows in his chapter in this volume. We could take the road less traveled: rather than a consensus approach that seeks to limit language to an agreed definition, we could sit with a plurality of meanings, no matter how uncomfortable that may be at times.
Numbers
If we consider the end of the Paleolithic in Europe, a period that covers 30,000 to 10,000 BCE, genetic data are available for only about twenty people. As numbers go, twenty is not much if we wish to understand the genetic makeup of ancient populations living across a 20,000-year time frame and distributed over an entire continent. The problem of numbers intensifies when we consider the amount of genetic material we are able to retrieve from these individuals: given degradation, our coverage of ancient genomes—that is, the amount of sequence we can retrieve and the confidence we have in this sequence—is inevitably far lower than it would be for their modern equivalents. Pragmatically, researchers must work with what they have, be it published aDNA libraries or incomplete sequences painstakingly obtained from a limited number of excavated remains. Controversy over numbers arises as genetic findings (taken from a few individuals) are used to hypothesize about the dynamics of multiple ancient populations (comprising many individuals). To put it crudely, what number of human burials and what number of genetic markers do we need before we can make meaningful inferences about the past?
An example from the Ancestra project illustrates that there is no easy answer to this question. To represent the genetic diversity of the Middle Neolithic in the northern half of France, archaeological and genetic data were obtained from multiple sites. The Pont-sur-Seine “Ferme de l’Île” site is located in the Aube in the Seine valley dating from 4,000-3,500 BCE and consists of a ditched enclosure, ditches, post structures, pits, and about fifty Neolithic burials. In terms of human remains, adults of both chromosomal sexes were represented along with twenty children. The Bergheim “Saulager” site located in Alsace, Haut-Rhin, revealed the existence of several protohistoric occupations, with sixty silos attributed to the Middle Neolithic. Of these, fourteen yielded human remains corresponding to complete individuals dated to 4,800–3,800 BCE. As a final example, we have the site of Escalles “Mont d’Hubert” in the Pas-de-Calais, a causewayed enclosure dating to around 4,000 BCE. Altogether, the human bones found here correspond to nine adults and eight children of various ages.
Intuitively, one might think that the first site, Ferme de l’Île, would show the most genetic diversity, given the comparatively large number of human burials found there. However, the genetic samples showed that all individuals found in this cemetery shared the same haplotype for mitochondrial DNA.19 As the name suggests, mitochondrial DNA is found in the mitochondria, structures inside a human cell that generate the chemical energy needed to drive the biochemical reactions of that cell. Notably, mitochondrial DNA is inherited intact from mother to child, allowing the team to identify maternally inherited relatedness between individuals. In contrast, the findings from the two other Neolithic sites showed a much broader mitochondrial diversity, similar to that associated with other Neolithic sites across Europe. For understanding kinship in terms of matrilineal relatedness within each site, the genetic data were informative. Yet if only one of these sites had been chosen to represent populations for the Neolithic in Northern France, a very limited and misleading picture would have emerged.
In the example described above, the team explored one defining genetic marker transmitted intact from only one parent—the mother. What happens if we increase the number of markers we look at, and if we look at not one parent but both?
The Ancestra project initially planned to study the complete mitochondrial genome, the Y-chromosome (inherited from father to son) and a selection of a hundred or so nuclear markers in each ancient genome. The idea was to enrich the data set by capturing information about the same genetic markers across all the samples. This enrichment technique would retrieve genetic information for direct comparison of samples, even in cases where very little DNA was available, due to degradation. For all our individuals (over 200 in total), mitochondrial analysis was complemented with data from the Y-chromosome and a panel of 120 genetic markers inherited from both parents. Whole genome sequencing was achieved for fifty-eight individuals, albeit with a low coverage, allowing the team to consider specificity (informative markers from all individuals) with quantity (as much material as could be retrieved from a few well-preserved individuals). When the team increased the number of markers and maximized the genetic information retrieved through whole genome sequencing, a much greater amount of information was available for analysis.
