Picturing prehistoric Fennoscandia -the art and science behind our ancient DNA paper
October 2018 saw the publishing of our paper on northern Fennoscandian ancient genomes, after several years of intense yet rewarding work by a small, highly devoted team consisting in its core of Thiseas C. Lamnidis and myself, patiently supported and coached by Stephan Schiffels, the PI of the Population Genetics Group at the Max Planck Insitute for the Science of Human History (https://doi.org/10.1038/s41467-018-07483-5). The publication, defining an ancient east-Eurasian proportion of ancestry in individuals both from a 3500-year old burial site Bolshoy Oleni Ostrov, and from an Iron Age Finnish lake burial of Levänluhta, got plenty of notion, especially in my small native Finland, where the first ancient DNA ever to be published was a major national event. Since then, however, I’ve gotten almost as many questions about the illustrations used for the press release, than about the content of the article itself. In occasions of such publications, the common policy is to use photographs illustrating the source of information, be it the archaeological sites or skeletal elements. Here, the photographs were either rarely available, or protected by strict user policies, and finally a thought emerged, to utilize a chance skill acquired in my previous life phases, to intersperse the scientific facts with glimpses envisioned for these past lives and deaths. For the people interested in the philosophy and inspiration behind the art and research entwined in the project, I wrote this piece to entertain more thought, and to introduce our study to a yet wider audience.
A good 200 years ago, naturalists would travel over the seas, to study the beauty and wonders of foreign continents and bring the newly assumed knowledge, stories and theories back home. Their aim was to impress wives and children, as well as kings and scholars: A large number of people, many of whom would remain illiterate all their lives. Cameras were yet to be invented, and even the most meticulous description, read thoughtfully by a fellow scientist, would have benefited from a detailed visual depiction. It is no wonder in this context, that the various audiences were best reached through paintings and drawings. Even the most professional pictures of the time possessed a touch of inspiration, and often offered a spark for the more excessive and exotic dreams of artists, poets and writers. The line drawn between art and science can be considered a novel invention; one which to my mind remains artificial at best. Today, laymen dream of the past times in the same way as the 18th century homemakers and kings did of the newly found lands: as intriguing but ever-elusive, distant worlds. With no other access to the people and places long gone, the scientists studying the physical remnants are left with the challenging yet inspiring task of translating the realities and symbols behind these lost environments.
The years spent on my genetics studies, and the experience shared by professionals around me, have taught me to avoid the temptation of storytelling within the scientific interpretation. Now, working on ancient population genetics, where our scientific take can reformat the academic and public view on prehistoric societies, I realize better than ever that a careful approach in stating the facts is especially called for. Nevertheless, to truly understand the meaning of my findings while analyzing the genetic data, I still find it tremendously helpful -not to mention fun- to imagine the narratives defining our past as vividly as possible. Instead of just assuming information, I try to resonate personally with what is known. I have to suspect I’m not alone in my wish to visualize the events that lead to the myriad of mixtures we see in the modern human variety -the mere existence of the archaeogenetics field stands to prove a huge amount of scientific imagination, creative combinations over disciplines, and thinking outside of the box. Perhaps it is not so preposterous then, to lend something from the Enlightenment period naturalists, to bring the long-ago lived lives closer to us with pictures, in attempt to channel their stories trough time.
In the Fennoscandian study, I was dealing with people from ancient northern landscapes, populations adapted to cold climates year-round and used to survive on hunting and fishing. Surrounding me then, were the smells of fire and the drying meat, the feel of tools and materials, sounds of animals carried in the air. Around me were the vast natural views; maybe a touch of excitement for a journey ahead, to where the familiar lands end and something unknown begins. Reflecting these adventurous sentiments, our genetic analyses also suggest that several waves of ancestral Siberian populations came to contact with the initial inhabitants in northern Fennoscandia in ancient times. Both the ancient people of our study, as well as the modern Uralic language speakers, such as Finns and Saami, carry the genetic traces originating from these voyagers of the frozen plains.
When we embarked on the journey with the Fennoscandian study, my experiences with human population genetics were rather limited. The historical human bones from Finland acquired for my project, were selected with paleopathological research in mind. They were young in comparison to most materials studied in the paleogenetics group at the University of Tübingen, and assumed to have little relevance from the population genetics perspective. It was, however, the practice to test the samples for mitochondrial human DNA (mtDNA), as it helped monitoring the possible contamination, and provided material for simple population analyses based on the maternal component. The oldest of the Finnish sites, an enigmatic Iron Age water burial site called Levänluhta, immediately stroke out as something different. The signals found in the mtDNA were pointing to the modern Saami population, in contrast to the majority of the general gene pool of the Finns. Such an intriguing finding naturally demanded more investigation. The projects concerning in-depth human population genetics lead by professor Johannes Krause, were now exceedingly done in the newly established Max Planck Institute for the Science of Human History, in Jena. This is also where the data processing of the highest quality Finnish samples was transferred to. Another doctoral student, an aspiring bioinformatician Thiseas Lamnidis, was set to try his wings on the emerging data, under the supervision of Stephan Schiffels. I remembered Stephan from his earlier visit to Tübingen, especially from a cascade of questions he had about the background of the Saami and the Finns -a characteristic curiosity I would later come to know as his trademark.
Further the analyses went, the clearer the Saami-connection became. It seemed we had tapped right into the essentials of early Finland, so far genetically unknown, if not entirely unexpected. The linguists had for a time claimed that Finnic-speaking people had replaced the earlier foraging and hunting populations in a long process, spanning from around 1000 CE, when the Saami languages were prevalent throughout the land, all the way to the 16th century. Saami, like many indigenous peoples across the world, have experienced persecution and mistreatment from the modern majority population, and thus the signals of continuity between them and the earliest genetically studied historical group were more than welcome. That said, our studies on ancient populations were not planned specifically with these questions in mind, nor were they at any point meant for looking to categorize people living today. It is clear that genes do not define the identity or cultural relations of people, and the complicated mixing of the past societies is a better show of that, than any. This holds true for Levänluhta as well: the grave goods reveal no specific affinity to any one neighboring culture, but rather suggest connections with several surrounding regions, with a variety of styles and crafts. The lake burial practice in itself is enigmatic enough. It’s impossible to say, whether the Levänluhta people were part of a wider cultural scene, obscured by settlement sites modified into farming land over the centuries, or whether their customs were unique and limited to their community. Whatever the case, the lake burial did ensure an exceptional level of preservation: instead of depositing the bodies into Finland’s acidic soils, the sunken remains laid covered in oxygen-free lake-bottom clay, safe from chemical destruction, while the small lake site slowly turned into a swamp. In time, the iron-rich water turned the bones into a deep rusty red -an expression that would shock the locals and spark imaginative theories of spooks and sacrifices, when the bones occasionally elevated and appeared from the bogholes. When we chose to illustrate the site for our press release, I imagined a sole moment in the long journey of these individuals, from evident oblivion, to the attention of the world through ancient DNA. My colleagues agreed the feeling in the image reflects tranquility and loneliness, something of the long wait before these forgotten people would be accredited with their own special place in history.
It eventually became obvious that to get more resolution, we should expand the study from our curious Iron Age people of Levänluhta, and reach further within the spatio-temporal dimensions. If the cultural connections were hard to assume, then where should we turn to look for the closest genetic relatives? Wolfgang Haak, a group leader of our Max Planck Institute in Jena working on the Bronze Age steppe and foraging cultures, had conducted studies on a site called Bolshoy Oleni Ostrov, ‘the Great Reindeer Island’ at the Kola Peninsula. Remains of both adults and children from an Early Metal Period population had been buried in the fine quartz and shell-rich sands of the island’s coastline some 3500 years back. The deceased had been endowed with elaborate lithic, bone and antler artifacts and buried inside wooden structures, resembling boats or perhaps Saami-type sledges. Some of the grave goods pointed out intriguing contacts with contemporary cultural horizons; the waffle-pattern decorated ceramics, for example, to the northern Finland or Norway, and part of the weaponry to connections with southern and western Scandinavia. Studies on the skull morphology, in turn, connected the group with modern Ugric-speaking Siberian groups and Neolithic Altaians. Mitochondrial DNA analyses were published in 2012 in the doctoral thesis of Clio der Sarkissian, and nuclear DNA studies on the individuals were only a natural continuation. On the Great Reindeer Island, in such a distant past, I imagined lives and worldviews would probably have been even more foreign, than the ones of the mysterious inhabitants of Levänluhta. On the other hand, these arctic landscapes still exist, and the modern native groups inhabiting the hostile climatic extremes are met with largely comparable challenges and experiences than the hunter-gatherers of the Early Metal Period might have had.
Browsing through images from today’s Kola Peninsula and its islands, I was immersed in the colors and atmospheres of their cold, eerily beautiful beaches. I soon felt obliged to make the ancient inhabitants of those magnificent landscapes apparent in a more potent way, than parading out pictures of their remains, and found myself sketching some likely situations through their eyes. In my mind, I followed the islanders to their fishing routes, to watch and hunt the seals, in wonder and awe of their grace in water, but also knowing how important their skins, meat and fat would be for their own survival over the freezing winter. Perhaps they sometimes stopped to admire the whales, and listened to their hauntingly beautiful songs mixing in the air with the cries of birds. And certainly some of them already followed the annual migration cycles of the animals lending their name to the Great Reindeer island. There is ample proof of early people navigating over large distances of the Siberian tundra, crossing the snowy plains and (rather conveniently) frozen swamps, using skis and sleighs. From Finland and Russia, there are many findings of sleigh runners, with dating spanning all the way back to the Mesolithic period.
Some of the Bolshoy Oleni Ostrov people would in fact have been likely to spend much of their lives trading, and looking for new contacts to share materials and skills with. As it often happens when traveling, forming relationships with foreign groups of people became inevitable. Ultimately, new families would form and the genes, perhaps along with parts of culture and language, translated to the new generations. In our analyses, these past admixtures appear as a spatio-temporal gradient: the most substantial amount of Siberian ancestry is represented by ancient people of Bolshoy Oleni Ostrov, with roughly a half of their genomic make-up assigning to it. Strong signals of the same ancestral genetic component are found later in time, in Levänluhta and modern Saami, resembling each other in this regard. Finally, diminished yet visible proportions remain in the Finno-Ugric populations today. We dated the mixing of this so called Siberian genetic component into the originally solely hunter-gatherer-like genetic makeup to around 4000 years ago, but whether this arrival actually happened in the ascetic coastal landscapes of Bolshoy Oleni Ostrov, or somewhere along the endless plains of Siberia, remains a mystery.
I feel privileged having been able to apply a novel view to these few lost moments, perhaps aiding a wider audience to appreciate these individuals who lived and died unaware of their future fame. My hope is, that understanding how much we are alike, independent of the age we live in, may also aid extent some compassion to our contemporaries. The age of mixing and migrations is far from over, and the reasons for human beings to cross great distances remain mainly unchanged: some must escape the pressures of famine, wars, or altering environments; others seek to improve their networks to gain wealth and influence. A scientific mind may reach over virtual boundaries out of shear curiosity, sometimes by climbing mountains, sometimes with a leap of combining disciplines. And sometimes, a distance between art and science is momentarily sewn together by an admirer of the early naturalists, in attempt to paint alive the scientific discoveries for those of their fellows more tethered to the ground by the gravity of time.
Originally published at https://medium.com on May 30, 2019.