The DNA of a 6000 year old chewing gum allows the portrait of a prehistoric girl

She lived at the present site of Syltholm, on the Island of Lolland, in Denmark, 5,700 years before our era. Nicknamed “Lola” echoing her place of life, she had black hair, blue eyes and dark skin. She loved duck and hazelnut. Finally, if her age is still unknown, she probably had mononucleosis. All its information comes from a simple prehistoric chewing gum of just a few centimeters perfectly preserved. Archaeologists from the University of Copenhagen have extracted the complete genome of Lola from DNA left by her saliva almost 6000 years ago – a first! At that time, during the Neolithic, Homo sapienswas still just a nomadic hunter-gatherer. To build certain tools, these hunters used birch tar, obtained after baking pieces of birch bark. Once moistened or chewed, this sticky plasticine became as malleable as Patafix. Scientists suspected that prehistoric men could also use it as chewing gum, it is now confirmed.

This primitive chewing gum would probably help them clean their teeth, reduce hunger or even satisfy a simple taste pleasure. On the piece of fossilized chewing gum, the researchers also identified several bacteria and viruses. If the majority of these microbes were harmless (we speak then of commensal bacteria, those composing our microbiota), some could have been the cause of diseases in Lola: Porphyromonas gingivalis , a bacterium causing periodontitis, bacteria linked to pneumonia as well as the Epstein-Barr virus, responsible for mononucleosis.

The writing was born well at that time but in the Middle East, therefore in a very different part of the world. Thus, in the absence of written records relating the life of these prehistoric populations, this incongruous discovery is invaluable for archaeologists trying to better understand their living conditions and their behavior. Furthermore, the presence of these microbes provides more information on the relationship between humans and their pathogens . “Our ancestors lived in a very different environment and had a very different lifestyle and diet than ours. Knowing the composition of their microbiota is very interesting in relation to current research concerning it , said in a press release Hannes Schrober, one of the authors of the study published inNature Communications . This discovery will help us better understand how pathogens have evolved and spread over time, how they are more virulent in such an environment and how they might behave in the future. “