An ancient piece of “chewing gum” has revealed a Danish woman born 5,700 years ago probably had dark skin, blue eyes and ate a diet including hazelnuts and duck.
Scientists examined the ancient piece of birch pitch which provided insights into the oral microbiome and the individual’s potential food sources.
Researchers from the University of Copenhagen said the discovery marks the first time an entire ancient human genome has been obtained from anything other than bones.
Based on the human genome, the researchers could tell the birch pitch was chewed by a female.She was genetically more closely related to hunter-gatherers from mainland Europe than to those who lived in central Scandinavia at the time.
Researchers also believe the woman had dark skin, dark hair and blue eyes, according to the study published in Nature Communications.
Traces of hazelnut and duck DNA was also found in the sample, indicating they may have made up part of her diet.
Associate Professor Hannes Schroeder from the Globe Institute, University of Copenhagen, who led the research, said: “It is amazing to have gotten a complete ancient human genome from anything other than bone.
“What is more, we also retrieved DNA from oral microbes and several important human pathogens, which makes this a very valuable source of ancient DNA, especially for time periods where we have no human remains.”
Birch pitch, which is created by heating birch bark, has been used as a glue since the Middle Pleistocene era – approximately 760,000 to 126,000 years ago.
Small lumps of the material have been found at archaeological sites and have often included tooth imprints, suggesting it was chewed.
In this study, the chewed birch pitch was found during archaeological excavations at Syltholm, east of Rodbyhavn in southern Denmark.
Additionally, the researchers extracted DNA from several oral microbiota from the pitch and found DNA that could be assigned to the Epstein-Barr Virus – known to cause infectious mononucleosis or glandular fever.
Prof Schroeder said such ancient chewing gums can aid in researching the composition of our ancestral microbiome and the evolution of human pathogens.
He said: “It can help us understand how pathogens have evolved and spread over time, and what makes them particularly virulent in a given environment.
“At the same time, it may help predict how a pathogen will behave in the future, and how it might be contained or eradicated.”