Fingerprint study suggests women, children helped build Terracotta Warriors

A recent study of fingerprints is challenging the long-held assumption that the Terracotta Warriors were exclusively constructed using male labor.

An analysis of 79 well-preserved fingerprints on the clay figurines suggests quite the opposite. Scientists measured the mean ridge breadth of the fingerprints using a Bayesian model. Unlike many prior studies, this study integrates both mean ridge breadth and ridge density (how many ridges fit in a given space) instead of treating them as independent predictors. The result showed that only 45 percent of the fingerprints were from adult male workers. Nearly 33 percent were from adult females, with roughly 22 percent coming from juveniles who were younger than 15 years old.

These findings provide the first quantitative biological evidence for a diverse workforce that included women and children. They may have even taken part in the production, transportation, and assembly of the Terracotta figures.

The result was published in the Journal of Cultural Heritage, as co-authored by the Emperor Qinshihuang's Mausoleum Site Museum in Xi'an, Shaanxi province, and the School of Archaeology of Shandong University in Jinan, Shandong province.

Of the 79 fingerprints recovered, 73 are surface fingerprints — left by craftspeople pressing directly into the wet clay during modeling and trimming. The remaining six came from the makers gripping small, pre-shaped clay pieces — like armor studs and belts — as they attached them.

The fingerprints were mostly found on separate components that had been made in advance, including heads, arms, and armor. The distribution corroborates a production method that is well documented: the parts were shaped in molds and by hand, then assembled one piece at a time.

The presence of fingerprints belonging to youths is consistent with historical records of young people assisting master crafters under the Qin apprenticeship system.

More proof comes from sporadic textual evidence from Qin legal documents and excavated artifacts. Inscriptions on Qin lacquerware include titles such as da nyuzi, meaning adult woman, xiao nyuzi, meaning young girl, and xiao nanzi, or young boy, indicating that women and children participated in lacquer production under state supervision.

"Whether this pattern extended to the massive Terracotta Army production project remains a critical unanswered question, with significant implications for our understanding of Qin labor systems and social organization," said Li Xiaoxi, an archaeologist from the museum who led the research.

The Qin household registration system set the age of eligibility for labor and military service at 15. The rules also counted female convicts as labor for earthworks. On top of that, state-run workshops ran apprenticeships where master artisans gave proper training. Together, these rules and practices formed the institutional backdrop enabling women and minors to take part in large construction projects, according to the paper.

Proof of women joining large construction in ancient times also appeared in other relics. Bricks on the ancient city wall in Nanjing, built from late Yuan Dynasty (1271-1368) to early Ming Dynasty (1368-1644), were engraved with names commonly associated with females. Leaving one's name was a way to record credit for work. Female bones were also unearthed from a pottery-making workshop in Shaanxi. They are believed to belong to female crafters from the Western Zhou Dynasty (c.11th century-771 BC).

"The construction of the Nanjing City Wall and the Ming imperial capital was a state-sponsored undertaking that conscripted millions of laborers from across the country. The population had declined sharply after the wars at the end of the Yuan Dynasty, which made it inevitable that women would supplement the workforce," said Zhao Mengwei, director of the academic study department of the Nanjing City Wall research center.

"Scattered clues give us grounds to infer that a considerable number of women took part. They either worked as kiln artisans, taking charge of firing the city bricks, or as labor workers, performing tasks such as clay preparation and earth carrying for brick production. The brick-firing skills could be passed down within families among artisan households, or learned temporarily amid the heavy workload," she said.

It is reasonable to surmise that behind the grueling brick-firing and construction work, many more women performed logistical tasks, such as preparing meals for crafters and conscripted laborers. "Though unrecorded in historical texts, their contributions were vital. This shows that cultural heritage is the legacy created by the broad masses of the people," she added.