Study: Paleo-proteomic analysis of Iron Age dental calculus provides direct evidence
of Scythian reliance on ruminant dairy (DOI: 10.1371/journal.pone.0339464)
A team of scientists has discovered that the diets of Scythian populations living in Iron Age Ukraine relied on milk from herd animals such as cows, sheep and goats-and in one instance, horses.
By analyzing 2,500-year-old dental plaque, the research team, which includes U-M anthropologist Alicia Ventresca-Miller, provided the first direct evidence that the diet of the Scythians included milk from various ruminants and horses. The study, conducted by an international team led by the University of Basel and the University of Zurich, was published in the journal PLOS One.
"It is interesting to note that not only were Scythians riding horses, potentially over long distances, but they were also milking horses and drinking horse milk," said Ventresca-Miller, associate curator of archaeological sciences and associate professor of anthropology.
For centuries, the Scythians have been regarded as highly mobile warriors who roamed the vast steppes of Eurasia during the Iron Age, an image that remains powerful to this day. In recent years, however, scientific research, much of which was done by Ventresca-Miller and the research team, has challenged this simple narrative. The so-called Scythians were not a unified group, but consisted of a diverse, multiethnic population with distinct cultural differences. Their lifestyles were equally diverse, with groups engaging in breeding of livestock and farming, while living in cities.
The study helps give a more accurate picture of how these ancient people lived, revealing that milk has been an integral part of their diets for thousands of years. The techniques used in the study-analyzing proteins from ancient dental plaque-can also help us understand more about the historical role of milk in the past.
Dental calculus as a biological archive
The research team examined dental calculus-mineralized dental plaque-from 28 individuals found at the Bilsk and Mamai-Gora sites in what is now Ukraine. Dental calculus acts as a biological archive of an individual's diet, as it traps tiny traces of the food consumed.
Using paleoproteomic analysis-a method that identifies preserved proteins-the researchers were able to determine for the first time which animal milk products Scythian communities actually consumed and from which species they derived.
They found proteins in six individuals that indicate the consumption of milk and processed milk products from ruminants such as cattle, sheep and goats. In one case, they also succeeded in detecting horse milk. The consumption of mare's milk from Scythians had previously been suspected mainly from historical texts but had not been directly proven.
"The detection of horse milk proteins in ancient dental plaque from people living during the Scythian period is an important finding," said study lead author Jaruschka Pecnik, a researcher at the University of Zurich and doctoral student at the University of Basel. "It shows that horses were not only used for transportation, warfare or symbolic purposes, but were also, at least occasionally, part of the food system."
However, the fact that horse milk proteins were only detected in the remains of one person raises new questions. For example, it is unclear whether the lack of certain milk proteins is because the proteins did not persist over time, or if it tells us about people's cultural practices. Some Scythians may have had special access to certain foods, or some livestock may have deliberately not been used for milk.
Reservoir of personal history
The study also opens up new perspectives in terms of methodology.
"Dental calculus is a remarkable reservoir of personal history," said study leader Shevan Wilkin, a biomolecular archaeologist at the University of Basel. "Since dental plaque is gradually formed and mineralized throughout a person's life, it allows us a very direct look at the foods actually consumed-beyond general assumptions about lifestyles or economic systems."
At the same time, the researchers emphasize that these findings are only a first step. Although the study provides clear evidence of the consumption of various dairy products, it does not yet paint a complete picture of the diet of Scythian communities.
Further research is needed to better understand regional differences, social factors and changes over time. Future studies will need to analyze the dental calculus of a significantly larger number of individuals from different regions of the Eurasian steppe in order to further explore the complex and dynamic dietary systems of the Iron Age steppe peoples.
