Archaeologists are trying to solve the mystery of a girl who was buried with the head of at least one finch in her mouth hundreds of years ago.
Although the skeleton was discovered by archaeologist Waldemar Chmielewski in southern Poland in Tunel Wielki Cave during excavations in 1967 and 1968, the burial had not been analyzed in detail until now. New radiocarbon dating indicates that the girl died around 300 years ago.
People in Europe stopped burying their dead in caves during the Middle Ages, making the burial of this girl highly unusual.
"Cave burials are generally absent from historical periods in Europe," a team of researchers wrote in a paper published online May 29 in the German journal Praehistorische Zeitschrift (Prehistoric Journal). "Consequently, the discovery of a post-medieval inhumation of a child buried with at least one bird head placed in the mouth in Tunel Wielki Cave is an exceptional find."
The fact that she has at least one bird head stuffed in her mouth is also unusual, and no other examples are known from this time in Europe, the researchers wrote in the journal article.
After analyzing the skeleton, the researchers, from the University of Warsaw and other institutions in Poland, found the girl had died between 10 and 12 years of age. Her bones also showed signs of arrested growth in later years, possibly the result of a metabolic disease. They didn't find any evidence of trauma, nor any clues about how the girl died. No grave goods, aside from the bird head placed in her mouth, were found.
Who was she?
To try to solve the mystery of who the girl was and why she was buried in this way, the team conducted a series of scientific tests and examined historical records. DNA tests indicated that the girl was likely from an area north of Poland, possibly around modern-day Finland or Karelia.
Historical records show that from 1655 to 1657, the area was occupied by an army led by King Charles X Gustav of Sweden. His army included many soldiers from Finland and Karelia, the records show, and those soldiers often traveled with their families. "The soldiers, for the most part of low rank, were commonly accompanied by wives, mistresses and sometimes maidservants," the researchers wrote.
Records from the 19th century also show that people in Karelia, a region that stretches over modern-day Russia and Finland, believed that someone who died in a forest had to be buried in a forest rather than in a cemetery. "Historically, this custom appears rooted in cosmological conceptions of a forest as being like a cemetery," the researchers wrote.
These finds led the researchers to suggest that this girl may have come to the area during the 1655-1657 war and that she may have died in the forest where the cave is located. The researchers noted that Ojców Castle, which housed many soldiers and their families, is located near the cave. The war pitted Sweden and its allies against a coalition of countries that included Poland, Russia and Denmark.
Related: 10 epic battles that changed history
Why she was buried with at least one finch head in her mouth remains unknown.
"Among many cultures, the souls of children have also been conceived in the form of small birds," the researchers wrote. "Nevertheless, in the period in question, birds were never deposited into graves, let alone being placed in the mouth of the deceased. The riddle of the unique child burial from Tunel Wielki Cave cannot be fully explained."
Originally published on Live Science.
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Owen Jarus is a regular contributor to Live Science who writes about archaeology and humans' past. He has also written for The Independent (UK), The Canadian Press (CP) and The Associated Press (AP), among others. Owen has a bachelor of arts degree from the University of Toronto and a journalism degree from Ryerson University.