Analysis of hair in a 2,800-year-old tomb in Siberia has yielded the earliest direct evidence of psychoactive cannabis use. The findings shed light on the plant's role in ancient societies. Cannabis – one of the most widely used psychoactive plants in the world – has been consumed for medicinal, recreational, and ritual purposes for thousands of years. However, the origins of the plant's use, particularly for its mind-altering properties, remain poorly understood; archaeological evidence of ancient consumption is limited by the poor preservation of plant remains. Although cannabis was cultivated in East Asia at least 6,000 years ago, likely initially for its oil-rich seeds, indirect evidence of its use for mind-altering effects dates back at least 2,500 years, including discoveries suggesting its role in funerary and ritual practices across Central Asia.
Here, Gino Caspari and colleagues present new archaeological evidence of cannabis use from the Tunnug 1 site – one of the earliest and most important monumental burial mounds in the Uyuk Valley of southern Siberia. At this site, Caspari et al. recovered more than 1,400 cannabis seeds associated with the burials, with their small size and physical characteristics suggesting they came from wild or wild-like plants. Radiocarbon dating indicated that the seeds were deposited around the beginning of the 8th century BCE (~2,800 years ago), coinciding with the construction of the burial site. What's more, human hair was also recovered from the burials. Importantly, chemical analysis of the hair detected cannabinol, a compound produced when THC (the psychoactive compound found in cannabis) oxidizes, alongside weaker chemical signatures consistent with THC itself. According to Caspari et al., the findings provide the earliest securely dated direct evidence supporting the idea that ancient people used cannabis for its mind-altering effects in cultural and ceremonial practices. "These data add to the growing global repertoire of archaeological evidence for ancient people using plants as mind-altering or mood-altering drugs," write the authors. "Early cannabis use thus emerges not simply as a pharmacological curiosity but as an indication of how ancient societies experimented with and ritualized the psychoactive qualities of the botanical world."
