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What is the earliest evidence of cannabis use?

The question asks about the earliest evidence of cannabis use. To answer this, we need to consider archaeological findings, historical texts, and scientific analyses.

The earliest evidence of cannabis use comes from archaeological findings in Central Asia and China.

• Archaeological Evidence:
  • 2,500-year-old braziers: Chemical analysis of incense burners from the Jirzankal Cemetery in the Pamir Mountains of western China revealed the presence of psychoactive cannabinoids, indicating cannabis was burned as part of mortuary rituals. This is some of the earliest clear evidence of cannabis being used for its psychoactive properties.[1]
  • 8,000-year-old site in Japan: Fossilized fruits from an 8000-year-old site in Japan are some of the oldest known evidence of cannabis.[3]
  • Haimenkou, Yunnan, Southwest China (1600-400 bc): Over 800 cannabis seeds were recovered, suggesting the crop was beginning to undergo evolution from its early domesticated form towards a diversified crop specialized for alternative uses, including larger oilseed/ fibre adapted varieties.[4]
  • Yanghai Tombs, Xinxiang, China (ca. 500 BCE): Cannabis sativa leaves, fruits, and shoots were recovered from a gravesite, suggesting ritualistic use.[5]
  • Okinoshima, Japan (ca. 8000 bc): Cannabis seeds were found, and they lack the caruncle of var. asperrima/kafiristanica, suggesting these are likely already a domesticated form of ssp. indica.[6]
  • Zhuzhai (ca. 5900−5800 bc): Cannabis grains were found, and their size is greater than known wild seeds, suggesting possible cultivation.[7]

• Historical Texts:
  • Atharva Veda (2000–1400 BCE): Mentions cannabis as one of the "five sacred plants" and refers to it as a "source of happiness," "joy-giver," and "liberator." [8]
  • Shennong Ben Cao Jing (ca. 100 CE): Describes the use of "cannabis fruit/seeds" and notes some psychodynamic effects.[9]

Considering the evidence, the earliest evidence of cannabis use includes:

• Linguistic Evidence:
  • The word "ma" (麻) in Chinese, meaning cannabis/hemp, has connotations of "numbed; tingling; senseless," which "apparently derived from the properties of the fruits and leaves, which were used as infusions for medicinal purposes."[10]

• The earliest clear evidence of cannabis being used for its psychoactive properties comes from the 2,500-year-old funerary incense burners from the Jirzankal Cemetery in the eastern Pamirs.[1]
• Fossilized fruits from an 8000-year-old site in Japan are some of the oldest known evidence of cannabis.[3]